Pollution: Choking Wild Animals

31 May, 2023

An ecosystem is the natural balance between organisms, plants, and animals in a particular place. Certain species of wildlife depend on particular species of plants, insects and organisms for survival. Even a small patch of forest can have a complete ecosystem of its own. So can a rivulet, a pond, a lake and sea. In any given landscape, there can be numerous ecosystems. This is what is called biodiversity.

Never before has biodiversity faced such destructive forces as it has in recent times from human activities. Almost half of what took millions of years to take shape and evolve has been destroyed by man in a very short time.

Man-made pollution is one of the main threats to wildlife habitat. Humans have regarded the air, water, and soil as waste receptacles, giving little consideration to the ecological consequences of pollution. Wildlife populations are constantly confronted with a massive array of pollutants released into the environment.

In the last 80 years, the world chemical output has grown 500-fold, contaminating entire landscapes, accumulating in bodies of animals and plants, and altering and disrupting the DNA of wildlife in those places. Out in the seas and oceans, destruction caused to marine life cannot be fathomed. Trash washed down rivers and city streets, mountains of plastic, garbage and debris, are finding their way into the oceans by the ton on a daily basis – causing massive disruption in coastal ecosystems. Pollution from industrial emissions, traffic and other commercial activities have eaten into the ozone layer and altered complete climatic patterns. Ecosystems that have survived and evolved through the ages, dependent on climate and seasonal cycles, have been totally derailed.

These destructive human activities are causing massive extinctions. Up to 30% of mammal, bird and amphibian species are already threatened with extinction, including: 1 out of 4 mammals, 1 out of 8 birds, 1 out of 3 amphibians, and 6 out of 7 marine turtles. A third of reef-building corals are threatened with extinction. If global temperatures rise by more than 3.5°C, up to 70% of the world’s known species risk extinction. Extinction risks are outpacing conservation successes.

Pollution Disrupting Ecosystems

Thousands of synthetic chemicals are being released into the environment at alarming rates, altering the distribution of naturally occurring substances. Wild animals are facing conditions they have never experienced before. These alien conditions disrupt the delicate biological balance that has evolved over thousands of years.

Toxic metals from human activities accumulate to create a bewildering number of hazards to wildlife. Animal agriculture, fossil fuels, mining, metal refining, and waste-water discharge create toxic levels of pollutants beyond what naturally cycles through soil, air and water.

Pollution is have detrimental effects on the health of wildlife. Synthetic chemicals, acid rain and oil are all toxic. Additional types of pollution harm wildlife in indirect ways, changing or destroying their habitats. Carbon dioxide is accumulating in the atmosphere, resulting in changes in climate and the distribution of habitats. The ozone layer is being damaged by chlorofluorocarbons, causing destruction from the effects of excessive ultraviolet radiation on wild animals and their food sources. Grasslands, marshes and canyons are being destroyed by solid waste landfills.

Air Pollution Harming Wildlife

Gases, solid particles and aerosols are polluting the air. Air pollution negatively affects wildlife by changing plant communities. Stunted plant growth from atmospheric ozone affects the quality of habitat and food sources.

Birds are threatened directly by coal power production exhaust, which damages their respiratory systems. Air pollution also indirectly threatens birds. pH level increases result in fish kills, causing a decline in food sources. Mercury accumulates in the food chain, wreaking havoc on predatory bird populations.

Acidic rivers and streams, resulting from acid rain, causes respiratory distress in fish. Clearer water from higher acid levels also results in temperature and light increases in the water, causing native fish to relocate to cooler and darker habitats. Amphibians have changed both physiologically and behaviorally due to air pollution. Ozone damages their immune systems.

Insects are especially susceptible to the dangers of air pollution. Air quality fluctuations can cause insects to relocate, affecting the plants and animals connected to them. Insects more resilient to air pollution digest organic waste less effectively, resulting in a buildup of organic waste when air pollution increases.

Metal smelters release toxic metals through tall smokestacks that have negative effects on wild animals. Pollutants cause environmental contamination both close to the source, and downwind of smelters.

Air pollution is damaging lung tissues of animals. Chlorofluorocarbons (CFCs) have damaged the ozone layer that protects the Earth from ultraviolet radiation. Ozone molecules near the ground damage wildlife lung tissues and reduces plant respiration by blocking openings in leaves. A plant not able to photosynthesize at a high rate due to inadequate respiration cannot grow. Holes in the ozone layer also cause skin cancer in wildlife.

Greenhouse gases from air pollution are warming the planet. Through photosynthesis, plants convert carbon dioxide into oxygen and use the carbon to grow. But the amount of carbon dioxide being released by human activities is much greater than plants can convert. Ice and frozen ground are melting near the Poles. As a result, habitats and resources are changing for plants and animals. Ocean warming and rising sea levels are affecting shallow marine environments, including coral reefs. Less rainfall, caused by global warming, is limiting water resources for plants and animals.

Air pollution is particularly hazardous to animals when in the form of acid rain. Acid rains kills fish by increasing water acidity. Rising pH (a measure of acidity) levels are destroying plants and trees.

Acid Rain Killing Wild Animals

Acid rain, primarily caused by sulfur and nitrogen released into the atmosphere from automobiles and the combustion of oil and coal, discharges toxic aluminum into water systems. Acid rain has numerous disastrous effects on ecosystems, especially aquatic ecosystems. pH levels are changed, killing many wild animals outright and throwing ecosystems completely out of balance.

Gravity draws acid rain towards water bodies in low areas. When the acidity in these water bodies increases, fish and other organisms lose their ability to survive and reproduce. Acid rain has already killed off fish populations in hundreds of lakes.

Water Pollution Detrimental To Wildlife

Water pollution is detrimental to wildlife. Frogs species are in decline. Water bodies polluted with nutrients are causing massive growths of toxic algae that are eaten by animals, resulting in diseases and deaths.

Mining operations result in weathering waste rock and ore deposits, creating "acid mine drainage." Acid mine drainage creates toxic water pollution.

Monumental amounts of toxic metals are released into the air by industries and automobiles. These toxins settle to the ground and are then transported by fallen rain, along with pesticides. "Storm water runoff" is carried to local sewer systems, streams, rivers, lakes and oceans. It is one of the largest sources of toxic water pollution.

Oil spills result in the deaths of countless wild animals. Oil coats animal fur and feathers reducing their insulating properties, and exposes animals to deadly toxins. The long-term effects of oil spills are more subtle, but just as detrimental. Toxic chemicals on beaches, in the water, and in the food web results in anemia, decreased disease resistance, impaired reproduction, cancers, birth defects and neurological damage.

In coastal belts where human habitation concentration has grown the most in the past few decades, wanton garbage disposal, especially of plastic, has almost completely wiped out marine ecosystems within miles of the shores. Spectacular creatures such as whales and dolphins, that were once a common sight for beach goers, have been driven from their natural habitat into deep seas – having lost their centuries-old feeding grounds to pollutants.

In closeted water bodies like lakes, pollutants like oil, detergents, nitrogen and phosphate can create havoc in its ecosystems by stimulating growth of unwanted plants and choking the water of oxygen so essential to the survival of fish.

Wild Animals Affected By Noise Pollution

Pollution is not always physical. Sound waves from oil rigs, ships and sonar travel for miles disrupting communication, hunting, migration, and reproduction of aquatic animals. Noise pollution from gas and oil explorations are causing mass strandings and chronic stress.

Animal Agriculture A Major Threat To Wildlife

Pollution from animal agricultural is one of the biggest threats to wildlife. Pesticide usage in agriculture has jumped 26-fold in the last 50 years causing serious consequences for the environment. Lakes, streams, drains and groundwater have been contaminated to an extent that not only are they not fit for use, entire ecosystems around them have perished. Chemical runoff leaches into streams, waterways and groundwater. Fertilizers alter nutrient systems in waterways, creating explosive growths of algae that deplete oxygen in the water. Around 400 dead zones have already been created as a result.

Animal agriculture produces significantly more greenhouse gases than all of the traffic in the world combined. Spouting out huge percentages of carbon dioxide and nitrous oxide, the industry is leaving behind pollutants known to remain in the atmosphere for more than 100 years. Animal waste also produces toxic levels of methane and ammonia, which leads to climate change as well as acid rain. Cows alone produce approximately 120lbs of manure per day, resulting in about 150 billion gallons of methane each day. Unmanageable amounts of animal waste is collected in cesspools and is either sprayed on fields or left to sit. The toxic fumes from the pools are emitted into the air and harm the environment.

Pesticides not only harm wild animals through long-term exposure via the food web; direct exposure also kills wild animals. Pesticides drift, decimating mammal, bird and fish populations.

Littering Killing Wildlife

Littering causes the deaths of many wild animals. Toxic trash can be fatal. Entanglement in litter is a common threat. Tons of plastic litter finds its way into the oceans, washed off streets and blown from landfills. Animals often mistake litter for food and attempt to eat the litter, resulting in fatalities. Litter accumulates in giant patches. Some is transported by currents and washed onto shore. Trillions of other pieces of decomposing plastic create gigantic swirling garbage patches in the ocean.

Effects of Household Pollutants On Wild Animals

Many households products contain toxic metals. Household waste-water often transports toxic metals into aquatic environments. Toxic chemicals used in households are washed down drains and flushed down toilets. Even more massive amounts of solvents, cleansers, and other chemicals are used in industrial activities, adding toxic pollutants to industrial waste-waters.

We Must Act Now

Pollution, along with habitat loss and degradation, over-exploitation, unsustainable practices, and invasive alien species, are affecting biodiversity around the globe. The result is the massive destruction of ecosystems and a frightening reduction in biodiversity.

Earth's ecological system has been in balance for millions of years, but is now threatened by human activities. Current extinction rates are likely to result in collapses of ecosystems on a global scale.

Pollution has had devastating impacts on wildlife. Most types of pollution are not necessary, and others can be drastically reduced. Technology is available that can significantly reduce pollution. Reduced consumption of fossil fuels would also bring down emissions of toxic metals and acid rain. Shifting to plant-based, organic farming would eliminate the massive amounts of pollutants produced by the animal agriculture industry.

Awareness, creativity, and a willingness to modify our lifestyles will curtail threats that pollution causes to both wildlife and humans. You can help wildlife and ecosystems by supporting environmental groups that are fighting polluting practices, as well as by making your own conscious decisions regarding eating choices, waste management, harmful chemicals and irresponsible household products.

Grasslands

31 May, 2023

Grasslands habitats are dominated by grasses with few large shrubs or trees. The three main types of grasslands include temperate grasslands, tropical grasslands or savannas and steppe grasslands. Grasslands have dry seasons and rainy seasons. They are susceptible to fires during dry seasons.

● Temperate grasslands have a lack trees and large shrubs and are dominated by grass. The soil has an upper layer that is nutrient-rich. Seasonal droughts result in fires that keep trees and shrubs from taking over the area.

● Tropical grasslands are located near the equator with warmer, wetter climates than temperate grasslands and more pronounced seasonal droughts. They are dominated by grasses, but also have scattered trees. The soil of tropical grasslands are porous and drain quickly. Tropical grasslands can be found in South America, Australia, Africa, India and Nepal.

● Steppe grasslands are dry grasslands that border on semi-arid deserts. Their grasses are much shorter than temperate and tropical grasslands and they lack trees except along rivers and streams.

Animals that inhabit grasslands include American bison, African elephants, lions and spotted hyenas.

Grasslands are areas where the vegetation is dominated by grasses and other herbaceous (non-woody) plants. They are also known as prairies and savannas. Grasslands occur naturally on all continents except Antarctica.

Grassland habitats are located in most climates, with the grasses varying in height from very short to very tall. Woody plants, shrubs or trees are found in some grasslands – forming scrubby grassland, semi-wooded grassland or savanna such as the African savanna plains. Some grasslands are called wood-pasture or woodland.

Grasslands may occur naturally or as the result of human activity. Grassland vegetation remains dominant in a particular area usually due to grazing, cutting or natural or manmade fires, all discouraging trees and shrubs from growing. Some of the world's largest expanses of grassland, located in Africa, are maintained mostly by wild herbivores.

Grasslands are often dependent on their region and differ around the world. In temperate areas, such as north-west Europe, they are dominated by perennial (year-round) grasses. In warmer climates, annual grasses make up most of the plant life.

Grassland habitats support a wealth of wildlife including mammals, birds, reptiles, amphibians and insects. Smaller animals are common as the open and uncovered areas make predators easier to see. Some large herbivorous mammals do also inhabit grasslands.

Grasslands once covered two thirds of the planet. As a result of human agriculture, only small pockets of original grassland ecosystems remain. Half of Africa remains grasslands.

Leopards Have Lost 75% Of Their Range

30 May, 2023

The leopard (Panthera pardus), one of the world’s most iconic big cats, has lost as much as 75 percent of its historic range. Animal agriculture, as well as illegal trade in leopard skins and parts and legal trophy hunting, are having a devastating effect on leopards.

Recent research challenges the conventional assumption in many areas that leopards remain relatively abundant and not seriously threatened. The leopard is a famously elusive animal, which is likely why it has taken so long to recognize its global decline.

Leopards historically occupied a vast range of approximately 35 million square kilometers (13.5 million square miles) throughout Africa, the Middle East and Asia. Today, however, they are restricted to approximately 8.5 million square kilometers (3.3 million square miles).

Scientists from the National Geographic Society’s Big Cats Initiative, the Zoological Society of London, Panthera and the International Union for Conservation of Nature spent three years reviewing more than 1,300 sources on the leopard’s historic and current range. The results confirmed conservationists’ suspicions that, while the entire species is not yet as threatened as some other big cats, leopards are facing a multitude of growing threats in the wild, and three subspecies have already been almost completely eradicated.

In addition, while African leopards face considerable threats, particularly in North and West Africa, leopards have also almost completely disappeared from several regions across Asia, including much of the Arabian Peninsula and vast areas of former range in China and Southeast Asia. The amount of habitat in each of these regions is plummeting, having declined by nearly 98 percent.

Leopards’ secretive nature, coupled with the occasional, brazen appearance of individual animals within mega-cities like Mumbai and Johannesburg, perpetuates the misconception that these big cats continue to thrive in the wild — when actually they are increasingly threatened. A severe blind spot has existed in the conservation of the leopard.

The status of the leopard in Southeast Asia is as perilous as the highly endangered tiger. The international conservation community must double down in support of initiatives ––protecting the species. Our next steps in this very moment will determine the leopard’s fate.

Leopards are capable of surviving in human-dominated landscapes provided they have sufficient cover, access to wild prey and tolerance from local people. In many areas, however, habitat is converted to farmland and native herbivores are replaced with livestock for growing human populations. This habitat loss, prey decline, conflict with livestock owners, illegal trade in leopard skins and parts and legal trophy hunting are all factors contributing to leopard decline.

More research is needed on the less studied subspecies. Of these subspecies, one — the Javan leopard (P. p. melas) — is currently classified as critically endangered by the IUCN, while another — the Sri Lankan leopard (P. p. kotiya) — is classified as endangered, highlighting the urgent need to understand what can be done to arrest these worrying declines.

Despite this troubling picture, some areas of the world inspire hope. Even with historic declines in the Caucasus Mountains and the Russian Far East/Northeast China, leopard populations in these areas appear to have stabilized and may even be rebounding with significant conservation investment through the establishment of protected areas and increased anti-poaching measures.

Leopards have a broad diet and are remarkably adaptable. Sometimes the elimination of active persecution by government or local communities is enough to jumpstart leopard recovery. However, with many populations ranging across international boundaries, political cooperation is critical.

Public Lands Being Hijacked

29 May, 2023

For over one hundred years, gas and oil production on public lands has caused harm to species and ecosystems and contaminated air, soil, and water. The manufacturing and drilling of oil results in public lands becoming fragmented, driving wildlife away and harming habitats. At the same time, fires, oil disasters and other pollutants result in the contamination of water reserves, both on the surface and underground. By building roads to connect to drilling sites, human activity in previously unharmed areas skyrockets, leading to littering, increased poaching, roadkill, and fires. What’s more, it becomes easier for foreign species to take over and overwhelm the native fauna and flora. Perhaps most importantly, by allowing the gas and oil industry to develop further our reliance on fossil fuels is strengthened, producing greenhouse gasses and facilitating global warming.

Massive environmental value is hidden in our oceans and public lands, ranging from clean water to clean air, and natural ecosystems providing essential habitat for some of our most endangered species. But fossil fuel is valuable monetarily, which is why the government is selling public lands to anyone willing to pay the highest bid. Corruption and greed plagues the decision making process of how to best manage our public lands and waters.

Our climate is at a crucial point. Unless we overcome our dependence on fossil fuels by 2050, we will be facing extreme phenomena such as flooded coasts, human health disasters and massive extinctions of wild species. Climate change is happening now, not tomorrow. With global warming set to boost the rate at which wildlife is pushed to extinction, there is no better use for our oceans and public lands than providing safe haven to species and protection of their ecosystems.

Despite the alarming messages, the government keeps sacrificing these habitats to the oil and gas industry, to which they have leased over 67 million acres – 55 times more land than the Grand Canyon National Park. More than 25 percent of all greenhouse emissions in the country comes from these leases, while some of our most valued lands are being destroyed.

Both our national and natural heritage pay a high toll. The nation’s public lands are industrialized, coastlines and pristine rivers are contaminated, underprivileged communities are undermined, and wildlife is pushed closer towards extinction. For every new fossil fuel lease, the world is burdened with additional climate disruption.

There is nothing rational in a policy that allows for the destruction of natural heritage so that more climate pollution can be produced. The federal fossil fuel leases in our oceans and on our public lands are unacceptable and need to stop. If we did this, we would spare the atmosphere of 450 billion tons of pollution. Vast areas of public lands, wildlife habitat and oceans would be saved in the process.

The Potential Greenhouse Gas Emissions of U.S. Federal Fossil Fuels report showed that by putting an end to the federal fossil fuel leases, we would prevent 450 billion tons of carbon pollutants from becoming potential greenhouse emissions. This comprises over 25 percent of the total emissions that are permitted, should the world adopt a target to prevent global warming from surpassing 2 degrees Celsius which would cause catastrophic consequences to humans and natural ecosystems worldwide.

It is impossible to stop climate change with the regulation of tailpipes and smokestacks alone; extracted fossil fuels are intended to be burned, so any policy aspiring to counter climate change should limit the fossil fuel supply. There is no better place to start this process than our oceans and public lands, which harbor significant biological and ecological value.

Why Save Endangered Species?

28 May, 2023

Since life began on Earth, countless creatures have come and gone, rendered extinct by naturally changing physical and biological conditions. Since extinction is part of the natural order, and if many other species remain, some people ask: “Why save endangered species? Why should we spend money and effort to conserve them? How do we benefit?”

Congress answered these questions in the preamble to the Endangered Species Act of 1973, recognizing that endangered and threatened species of wildlife and plants “are of esthetic, ecological, educational, historical, recreational, and scientific value to the Nation and its people.” In this statement, Congress summarized convincing arguments made by scientists, conservationists, and others who are concerned by the disappearance of unique creatures. Congress further stated its intent that the Act should conserve the ecosystems upon which endangered and threatened species depend.

Although extinctions occur naturally, scientific evidence strongly indicates that the current rate of extinction is much higher than the natural or background rate of the past. The main force driving this higher rate of loss is habitat loss. Over-exploitation of wildlife for commercial purposes, the introduction of harmful exotic (nonnative) organisms, environmental pollution, and the spread of diseases also pose serious threats to our world’s biological heritage.

Conservation actions carried out in the United States under the Endangered Species Act have been successful in preventing extinction for 99 percent of the species that are listed as endangered or threatened. However, species loss on a global scale continues to increase due to the environmental effects of human activities.

Biologists estimate that since the Pilgrims landed at Plymouth Rock in 1620, more than 500 species, subspecies, and varieties of our nation’s plants and animals have become extinct. The situation in earth’s most biologically rich ecosystems is even worse. Tropical rainforests around the world, which may contain up to one half of all living species, are losing millions of acres every year. Uncounted species are lost as these habitats are destroyed. In short, there is nothing natural about today’s rate of extinction.

BENEFITS OF DIVERSITY

How many species of plants and animals are there? Although scientists have classified approximately 1.7 million organisms, they recognize that the overwhelming majority have not yet been cataloged. Between 10 and 50 million species may inhabit our planet. None of these creatures exists in a vacuum. All living things are part of a complex, often delicately balanced network called the biosphere. The earth’s biosphere, in turn, is composed of countless ecosystems, which include plants and animals and their physical environments. No one knows how the extinction of organisms will affect the other members of its ecosystem, but the removal of a single species can set off a chain reaction affecting many others. This is especially true for “keystone” species, whose loss can transform or undermine the ecological processes or fundamentally change the species composition of the wildlife community.

CONTRIBUTIONS TO MEDICINE

One of the many tangible benefits of biological diversity has been its contributions to the field of medicine. Each living thing contains a unique reservoir of genetic material that has evolved over eons. This material cannot be retrieved or duplicated if lost. So far, scientists have investigated only a small fraction of the world’s species and have just begun to unravel their chemical secrets to find possible human health benefits to mankind.

No matter how small or obscure a species, it could one day be of direct importance to us all. It was “only” a fungus that gave us penicillin, and certain plants have yielded substances used in drugs to treat heart disease, cancer and a variety of other illnesses. More than a quarter of all prescriptions written annually in the United States contain chemicals discovered in plants. If these organisms had been destroyed before their unique chemistries were known, their secrets would have died with them.

A few hundred wild species have stocked our pharmacies with antibiotics, anti-cancer agents, pain killers and blood thinners. The biochemistry of unexamined species is an unfathomed reservoir of new and potentially more effective substances. The reason is found in the principles of evolutionary biology. Caught in an endless “arms race” with other forms of life, these species have devised myriad ways to combat microbes and cancer-causing runaway cells. Plants can make strange molecules that may never occur to a chemist. For example, the anti-cancer compound taxol, originally extracted from the bark of the Pacific yew tree, is “too fiendishly complex” a chemical structure for researchers to have invented on their own, said a scientist with the U.S. National Cancer Institute. Taxol has become the standard treatment for advanced cases of ovarian cancer, which strikes thousands of women every year. But until the discovery of taxol’s effectiveness, the Pacific yew was considered a weed tree of no value and was routinely destroyed during logging operations.

BIODIVERSITY & AGRICULTURE

Thomas Jefferson once wrote that “the greatest service which can be rendered any country is to add a useful plant to its culture, especially a breadgrain.” It has been estimated that there are almost 80,000 species of edible plants, of which fewer than 20 produce 90 percent of the world’s food. If underutilized species are conserved, they could help to feed growing populations. One grain native to the Great Lakes States, Indian wild rice, is superior in protein to most domesticated rice, and its increasing commercial production earns millions of dollars annually.

ENVIRONMENTAL MONITORS

Many individual species are uniquely important as indicators of environmental quality. The rapid decline in bald eagles and peregrine falcons in the mid-20th century was a dramatic warning of the dangers of DDT—a strong, once widely used pesticide that accumulates in body tissues. (It hampered fertility and egghatching success in these species.) In another example, lichens and certain plants like the eastern white pine are good indicators of excess ozone, sulfur dioxide, and other air pollutants. Species like these can alert us to the effects of some contaminants before more damage is done.

Freshwater mussels are also very effective environmental indicators. The eastern United States boasts the richest diversity of freshwater mussels in the world. These animals are filter feeders, drawing in water and straining out food particles. Their method of feeding helps to keep our waters clean. But because mussels filter material from the water, they are often the first animals to be affected by water pollution. They tend to accumulate whatever toxins, such as chemicals in agricultural and industrial runoff, are present in their habitat. Too much pollution can eliminate the mussels. Other threats to mussel populations include siltation, the introduction of competing nonnative mussels, stream channelization and dredging, and the impoundment of free-flowing streams and rivers. Today, most native freshwater mussel species are considered to be endangered, threatened or of special concern.

ECOSYSTEM SERVICES

As the pioneering naturalist Aldo Leopold once stated, “To keep every cog and wheel is the first precaution of intelligent tinkering.” As we tinker with ecosystems through our effects on the environment, what unexpected changes could occur? One subject of increasing concern is the impacts these effects can have on “ecosystem services,” which is a term for the fundamental life-support services provided by our environment.

Ecosystem services include air and water purification, detoxification and decomposition of wastes, climate regulation, regeneration of soil fertility, and the production and maintenance of biological diversity. These are the key ingredients of our agricultural, pharmaceutical, and industrial enterprises. Such services are estimated to be worth trillions of dollars annually. Yet because most of these services are not traded in economic markets, they carry no price tags that could alert society to changes in their supply or declines in their functioning. We tend to pay attention only when they decline or fail.

An emerging field called phytoremediation is an example of the ecosystem services provided by plants. Phytoremediation is a process that uses plants to remove, transfer, stabilize and destroy contaminants in soil and sediment. Certain plant species known as metal hyperaccumulators have the ability to extract elements from the soil and concentrate them in the easily harvested plant stems, shoots, and leaves. The alpine pennycress, for example, doesn’t just thrive on soils contaminated with zinc and cadmium; it cleans them up by removing the excess metals. In the home, houseplants under some conditions can effectively remove benzene, formaldehyde and certain other pollutants from the air.

OTHER ECONOMIC VALUES

Some benefits of animals and plants can be quantified. For example, the Texas Parks and Wildlife Department calls birding “the nation’s fastest growing outdoor recreation.” It estimates that birders pump an estimated $400 million each year into the state’s economy. A host of small rural towns host festivals to vie for the attention of these birders. Nationwide, the benefits are even more amazing. Wildlife watching—not just bird watching—generates billions of dollars in economic benefits to nations each year.

INTANGIBLE VALUES

If imperiled plants and animals lack a known benefit to mankind, should we care if they disappear? If a species evolves over millennia or is created by divine intent, do we have a right to cause its extinction? Would our descendants forgive us for exterminating a unique form of life? Such questions are not exclusive to scientists or philosophers. Many people believe that every creature has an intrinsic value. The loss of plant and animal species, they say, is not only shortsighted but wrong, especially since an extinct species can never be replaced. Eliminating entire species has been compared to ripping pages out of books that have not yet been read. We are accustomed to a rich diversity in nature. This diversity has provided inspiration for countless writers and artists, and all others who treasure variety in the natural world.

Sea Turtles Face Plastic Deluge Danger

27 May, 2023

More than half the world’s sea turtles have ingested plastic or other human rubbish. Recent research indicates that approximately 52 percent of turtles world-wide have eaten debris.

Threats to marine turtle species come from an estimated four million to 12 million tons of plastic which enter the oceans annually. Plastic ingestion can kill turtles by blocking the gut or piercing the gut wall, and can cause other problems through the release of toxic chemicals into the animals’ tissues.

Plastics and other litter that enter marine environments are mistaken for food or eaten accidentally by turtles and other wildlife. Olive ridley turtles (Lepidochelys olivacea) are at the highest risk, due to their feeding behavior and distribution. Olive ridley turtles commonly eat jellyfish and other floating animals, and often feed in the open ocean, where debris accumulates.

The east coasts of Australia and North America, Southeast Asia, southern Africa, and Hawaii are particularly dangerous for turtles due to a combination of debris loads and high species diversity.

Other reptiles, aquatic mammals and fish are common victims of ocean litter. Seabirds are especially high risk for for marine debris. A study discovered that more than 60 percent of seabird species had ingested debris, and that number is expected to reach 99 percent by 2050.

Desert Features

26 May, 2023

Sand covers only about 20 percent of the Earth's deserts. Most of the sand is in sand sheets and sand seas vast regions of undulating dunes resembling ocean waves "frozen" in an instant of time. Nearly 50 percent of desert surfaces are plains where eolian deflation removal of fine-grained material by the wind has exposed loose gravels consisting predominantly of pebbles but with occasional cobbles. The remaining surfaces of arid lands are composed of exposed bedrock outcrops, desert soils, and fluvial deposits including alluvial fans, playas, desert lakes, and oases. Bedrock outcrops commonly occur as small mountains surrounded by extensive erosional plains.

Oases are vegetated areas moistened by springs, wells, or by irrigation. Many are artificial. Oases are often the only places in deserts that support crops and permanent habitation.

Soils

Soils that form in arid climates are predominantly mineral soils with low organic content. The repeated accumulation of water in some soils causes distinct salt layers to form. Calcium carbonate precipitated from solution may cement sand and gravel into hard layers called "calcrete" that form layers up to 50 meters thick.

Caliche is a reddish-brown to white layer found in many desert soils. Caliche commonly occurs as nodules or as coatings on mineral grains formed by the complicated interaction between water and carbon dioxide released by plant roots or by decaying organic material.

Plants

Most desert plants are drought-or salt-tolerant. Some store water in their leaves, roots, and stems. Other desert plants have long tap roots that penetrate the water table, anchor the soil, and control erosion. The stems and leaves of some plants lower the surface velocity of sand carrying winds and protect the ground from erosion.

Deserts typically have a plant cover that is sparse but enormously diverse. The Sonoran Desert of the American Southwest has the most complex desert vegetation on Earth. The giant saguaro cacti provide nests for desert birds and serve as "trees" of the desert. Saguaro grow slowly but may live 200 years. When 9 years old, they are about 15 centimeters high. After about 75 years, the cacti are tall and develop their first branches. When fully grown, saguaro are 15 meters tall and weigh as much as 10 tons. They dot the Sonoran and reinforce the general impression of deserts as cacti-rich land.

Although cacti are often thought of as characteristic desert plants, other types of plants have adapted well to the arid environment. They include the pea family and sunflower family. Cold deserts have grasses and shrubs as dominant vegetation.

Water

Rain does fall occasionally in deserts, and desert storms are often violent. A record 44 millimeters of rain once fell within 3 hours in the Sahara. Large Saharan storms may deliver up to 1 millimeter per minute. Normally dry stream channels, called arroyos or wadis, can quickly fill after heavy rains, and flash floods make these channels dangerous. More people drown in deserts than die of thirst.

Though little rain falls in deserts, deserts receive runoff from ephemeral, or short-lived, streams fed by rain and snow from adjacent highlands. These streams fill the channel with a slurry of mud and commonly transport considerable quantities of sediment for a day or two.

Although most deserts are in basins with closed, or interior drainage, a few deserts are crossed by 'exotic' rivers that derive their water from outside the desert. Such rivers infiltrate soils and evaporate large amounts of water on their journeys through the deserts, but their volumes are such that they maintain their continuity. The Nile, the Colorado, and the Yellow are exotic rivers that flow through deserts to deliver their sediments to the sea.

Lakes form where rainfall or meltwater in interior drainage basins is sufficient. Desert lakes are generally shallow, temporary, and salty. Because these lakes are shallow and have a low bottom gradient, wind stress may cause the lake waters to move over many square kilometers. When small lakes dry up, they leave a salt crust or hardpan. The flat area of clay, silt, or sand encrusted with salt that forms is known as a playa. There are more than a hundred playas in North American deserts. Most are relics of large lakes that existed during the last Ice Age about 12,000 years ago. Lake Bonneville was a 52,000-square-kilometer lake almost 300 meters deep in Utah, Nevada, and Idaho during the Ice Age. Today the remnants of Lake Bonneville include Utah's Great Salt Lake, Utah Lake, and Sevier Lake. Because playas are arid land forms from a wetter past, they contain useful clues to climatic change.

Eolian Processes

Eolian processes pertain to the activity of the winds. Winds may erode, transport, and deposit materials, and are effective agents in regions with sparse vegetation and a large supply of unconsolidated sediments. Although water is much more powerful than wind, eolian processes are important in arid environments.

Wind erodes the Earth's surface by deflation, the removal of loose, fine-grained particles by the turbulent eddy action of the wind, and by abrasion, the wearing down of surfaces by the grinding action and sand blasting of windborne particles.

Most eolian deflation zones are composed of desert pavement, a sheetlike surface of rock fragments that remains after wind and water have removed the fine particles. Almost half of the Earth's desert surfaces are stony deflation zones. The rock mantle in desert pavements protects the underlying material from deflation.

Particles are transported by winds through suspension, saltation, and creep. Small particles may be held in the atmosphere in suspension. Upward currents of air support the weight of suspended particles and hold them indefinitely in the surrounding air. Typical winds near the Earth's surface suspend particles less than 0.2 millimeters in diameter and scatter them aloft as dust or haze.

Saltation is downwind movement of particles in a series of jumps or skips. Saltation normally lifts sand-size particles no more than one centimeter above the ground, and proceeds at one-half to one-third the speed of the wind. A saltating grain may hit other grains that jump up to continue the saltation. It may also hit larger grains that are too heavy to hop, but that slowly creep forward as they are pushed by saltating grains. Surface creep accounts for as much as 25 percent of grain movement in a desert.

Eolian turbidity currents are better known as dust storms. Air over deserts is cooled significantly when rain passes through it. This cooler and denser air sinks toward the desert surface. When it reaches the ground, the air is deflected forward and sweeps up surface debris in its turbulence as a dust storm. Crops, people, villages, and possibly even climates are affected by dust storms.

Most of the dust carried by dust storms is in the form of silt-size particles. Deposits of this windblown silt are known as loess. The thickest known deposit of loess, 335 meters, is on the Loess Plateau in China. In Europe and in the Americas, accumulations of loess are generally from 20 to 30 meters thick.

Small whirlwinds, called dust devils, are common in arid lands and are thought to be related to very intense local heating of the air that results in instabilities of the air mass. Dust devils may be as much as one kilometer high.

Eolian Deposition

Wind-deposited materials hold clues to past as well as to present wind directions and intensities. These features help us understand the present climate and the forces that molded it. Wind deposited sand bodies occur as sand sheets, ripples, and dunes.

Sand sheets are flat, gently undulating sandy plots of sand surfaced by grains that may be too large for saltation. They form approximately 40 percent of eolian depositional surfaces. The Selima Sand Sheet, which occupies 60,000 square kilometers in southern Egypt and northern Sudan, is one of the Earth's largest sand sheets.

The Selima is absolutely flat in some places; in others, active dunes move over its surface. Wind blowing on a sand surface ripples the surface into crests and troughs whose long axes are perpendicular to the wind direction. The average length of jumps during saltation corresponds to the wavelength, or distance between adjacent crests, of the ripples. In ripples, the coarsest materials collect at the crests. This distinguishes small ripples from dunes, where the coarsest materials are generally in the troughs.

Accumulations of sediment blown by the wind into a mound or ridge, dunes have gentle upwind slopes on the wind-facing side. The downwind portion of the dune, the lee slope, is commonly a steep avalanche slope referred to as a slipface. Dunes may have more than one slipface. The minimum height of a slipface is about 30 centimeters.

Sand grains move up the dune's gentle upwind slope by saltation and creep. When particles at the brink of the dune exceed the angle of repose, they spill over in a tiny landslide or avalanche that reforms the slipface. As the avalanching continues, the dune moves in the direction of the wind.

A worldwide inventory of deserts has been developed using images from satellites and from space and aerial photography. It defines five basic types of dunes: crescentic, linear, star, dome, and parabolic.

The most common dune form on Earth and on Mars is the crescentic. Crescent-shaped mounds generally are wider than long. The slipface is on the dune's concave side. These dunes form under winds that blow from one direction, and they also are known as barchans, or transverse dunes.

Some types of crescentic dunes move faster over desert surfaces than any other type of dune. A group of dunes moved more than 100 meters per year between 1954 and 1959 in China's Ningxia Province; similar rates have been recorded in the Western Desert of Egypt. The largest crescentic dunes on Earth, with mean crest-to-crest widths of more than 3 kilometers, are in China's Taklimakan Desert.

Straight or slightly sinuous sand ridges typically much longer than they are wide are known as linear dunes. They may be more than 160 kilometers long. Linear dunes may occur as isolated ridges, but they generally form sets of parallel ridges separated by miles of sand, gravel, or rocky interdune corridors. Some linear dunes merge to form Y-shaped compound dunes. Many form in bidirectional wind regimes. The long axes of these dunes extend in the resultant direction of sand movement.

Radially symmetrical, star dunes are pyramidal sand mounds with slipfaces on three or more arms that radiate from the high center of the mound. They tend to accumulate in areas with multi-directional wind regimes. Star dunes grow upward rather than laterally. They dominate the Grand Erg Oriental of the Sahara. In other deserts, they occur around the margins of the sand seas, particularly near topographic barriers. In the southeast Badain Jaran Desert of China, the star dunes are up to 500 meters tall and may be the tallest dunes on Earth.

Oval or circular mounds that generally lack a slipface, dome dunes are rare and occur at the far upwind margins of sand seas. U-shaped mounds of sand with convex noses trailed by elongated arms are parabolic dunes. Sometimes these dunes are called U-shaped, blowout, or hairpin dunes, and they are well known in coastal deserts. Unlike crescentic dunes, their crests point upwind.

The elongated arms of parabolic dunes follow rather than lead because they have been fixed by vegetation, while the bulk of the sand in the dune migrates forward. The longest known parabolic dune has a trailing arm 12 kilometers long.

Occurring wherever winds periodically reverse direction, reversing dunes are varieties of any of the above types. These dunes typically have major and minor slipfaces oriented in opposite directions.

All these dune types may occur in three forms: simple, compound, and complex. Simple dunes are basic forms with a minimum number of slipfaces that define the geometric type. Compound dunes are large dunes on which smaller dunes of similar type and slipface orientation are superimposed, and complex dunes are combinations of two or more dune types. A crescentic dune with a star dune superimposed on its crest is the most common complex dune.

Simple dunes represent a wind regime that has not changed in intensity or direction since the formation of the dune, while compound and complex dunes suggest that the intensity and direction of the wind has changed.

Exploring Ways To Coexist With Wildlife

25 May, 2023

Although protected areas such as national parks can play a crucial role in conserving wildlife, most species of large carnivores and large herbivores also depend on being able to occupy human-dominated landscapes. This sharing of space is often associated with conflicts between humans and wildlife, and between different groups of humans with divergent interests. In order to achieve a situation that can be described as "coexistence", there is a need to develop a more nuanced and realistic understanding of what this state looks like.

Recent research looks at ways to improve the ability of humans and carnivores to co-exist, which is crucial to carnivore conservation efforts around the world. Based on studies in areas as diverse as North America, Europe and Asia on species such as wolves, tigers, leopards, lynx and bears, researchers note that large carnivores need larger ranges than many protected areas afford. This means that carnivores often come in contact with human populations that are sometimes less than welcoming.

What actions could help mitigate the negative impacts of these contacts, allowing both humans and carnivores to more peacefully coexist in shared landscapes? Scientists suggest that mutual adaptations are key to success. Not only do wild animals have to behaviorally adapt to the presence of humans, but humans also have to adapt their behavior to the presence of wild animals.

Studies have shown that many species of large carnivores show an incredible ability to occupy heavily modified human-dominated landscapes. Many human societies also show a wide range of adaptations to the proximity of large carnivores. This includes changes to the way they farm and the adoption of cultural or religious practices to "negotiate" their relationship with their wild neighbors.

However, in many areas these adaptations have been lost, either due to a temporary absence of large carnivores or in the face of changing social-economic situations. The result is often severe conflicts of both an economic and social nature. Realizing the necessity of adaptation by both humans and the carnivores is a key first step towards transforming conflict to coexistence. Conservation efforts that fail to focus on both halves of the equation are doomed to fail.

A factor for success has to do with recognizing that a state of coexistence does not involve an idealized absence of conflict. Rather than trying to eliminate all risk, which can mean eliminating a species, we must explore ways to keep risks below tolerable levels. That involves understanding what factors influence tolerance.

While some communities may not tolerate any risks from carnivores, others may tolerate high risks because they attribute carnivores with ecological and cultural benefits that exceed those risks. In many communities, the priorities of various stakeholder groups are still sometimes at odds, and there is a reduced trust in authorities. Interventions such as new policies must take into account local concerns such as the adoption of novel decision-making strategies that give voice to varying viewpoints.

The challenges are surmountable through the help of community leaders, conservation organizations, and state or federal agencies. Insights from studies on coexistence can help reconcile debates about carnivore conservation in shared landscapes and advance broader discourses in conservation such as those related to rewilding, novel ecosystems, and land-sharing vs. land-sparing.

In many ways, large carnivores represent the ultimate test for human willingness to make space for wildlife on a shared planet. If it is possible to find ways to coexist with these species, it should be possible to coexist with any species.

Forests

22 May, 2023

Forest biomes are dominated by trees and extend over one-third of the earth's land surface. There are three main types of forests—temperate, tropical and boreal. Each type has a different assortment of animals, climate characteristics and species compositions.

● Temperate forests are in temperate regions of the earth including North America, Europe and Asia. They have four well-defined seasons and a growing season between 140 and 200 days. Rainfall takes place throughout the year and soils are nutrient-rich.

● Tropical forests are located in equatorial regions between 23.5°N and 23.5°S latitude. They experience two seasons, a dry season and a rainy season. The length of each day varies little throughout the year. Soils in tropical forests are nutrient-poor and acidic.

● Boreal forests make up the largest terrestrial habitat. They are a band of coniferous forests located in the high northern latitudes between about 50°N and 70°N. Boreal forests create a circumpolar band of habitat from Canada, to northern Europe, to eastern Russia. They are bordered by tundra habitat to the north and temperate forest habitat to the south.

Some of the wildlife that inhabit the forest biome include deer, bears, wolves, moose, caribou, gorillas, squirrels, chipmunks, birds, reptiles and insects.

TEMPERATE FORESTS

Temperate forests are found in a wide range of climates and are some of the richest habitats earth. Temperate forests are home to a variety of plants and animals. Some live within them year-round, while migratory animals visit them seasonally.

The two main types of temperate forests are deciduous forests and evergreen forests.

Deciduous forests contain trees that loose their leaves in the fall. They are usually located in the Northern Hemisphere in parts of North America, Europe and Japan.

Evergreen forests are made up of trees that don't lose their leaves in the fall. They usually are found in warmer climates in South America, southern Europe, South Africa and parts of southern Australia. A more varied range of wildlife is often found in evergreen forests than deciduous forests.

A wide variety of animals call temperate forests home. Mammals, reptiles, amphibians, birds and insects live in temperate forests. The most common mammals are deer, squirrels, birds and wild boars.

Since food is plentiful in evergreen forests year round, even more varieties of wildlife inhabit them. Reptiles, amphibians, birds, mammals and insects are plentiful in evergreen forests.

Temperate forests once covered huge areas of the Northern Hemisphere. As a result of logging and deforestation for agriculture, most forests are already gone.

CONIFEROUS FORESTS

Coniferous forests are located in the far north, many within the Arctic Circle. They are predominantly home to conifers, the toughest and longest living trees. Conifers grow close together resulting in dense forests that are sheltered.

Coniferous forests include boreal forests and temperate forests.

Boreal forests stretch across the far north. Temperate coniferous forests are located in western North America, New Zealand and Chile. Some trees in the temperate coniferous forests in North America are over 500 years old.

Boreal coniferous forests stretch across the far north from Siberia, through Northern Europe, to Alaska, covering a distance of 6 million square miles. They are 1,000 miles wide in places. A large proportion of boreal coniferous forest is in the Arctic Circle, where plants and animals are well adapted to cold temperatures.

While fewer plant and animal species are found in coniferous forests compared to temperate forests and rainforests, many plants and animals still live within them. Conifer trees withstand the cold. Their pine needles are acidic, which passes into the soil when needles drop, allowing only acid loving plants to survive in coniferous forests. Only herbivores that survive on acidic plants can inhabit coniferous forests.

Insects make up the majority of animals found in coniferous forests. The dense trees provide ideal habitat for them to build their nests. Deer, elk, wolves and bears are also common in coniferous forests.

Coniferous forests are the least affected forests by humans. The trees are softwood and usually only used for making paper. Larger areas of coniferous forests are being logged however, as paper demand increases.

RAINFORESTS

Rainforests are home to more than 50% of all living species on the planet. They receive an abundance of rain and contain extremely diverse wildlife. The two main types of rainforest are tropical rainforests and seasonal rainforests.

Tropical rainforests are close to the Equator where the climate is warm, providing ideal conditions for plants. 170,000 of the world’s 250,000 known plant species are found in tropical rainforests. They have various layers of canopy providing a wide variety of habitats for animals. A large collection of tall tree species is made possible by a constant water flow. Tropical forests are home to smaller primates and bird species than seasonal rainforests.

Seasonal rainforests are usually further away from the Equator. Their climate is less stable then tropical rainforests. Rather than rain being dispersed evenly throughout the year, it comes all at once in what is called the monsoon. Trees in seasonal rainforests are generally much smaller than those in tropical rainforests. Larger animals inhabit the changing seasonal rainforests, such as tigers, primates and large snakes.

The broad array of animals found in rainforests include mammals, reptiles, birds and invertebrates. Mammals include primates, wildcats and tapirs. Reptiles include a variety of snakes, turtles and lizards. Numerous species of birds and insects live in rainforests. Fungi is common, which feed on the decomposing remains of plants and animals. Many animal species have adopted a tree-dwelling (arboreal) lifestyle in the rainforest. Food is abundant in the forests due to the amount of water and plant life.

Numerous plant and animal species are rapidly disappearing from rainforests due to deforestation, habitat loss and other human activities. Around 50 million people live in rainforests. Their habitat and culture is also threatened as an alarming amount of rainforest land disappears each year.

10 Interesting Facts About Energy

22 May, 2023

Always turn off lights when you leave the room, unless... You should always turn off the light when you leave a room. This can save a lot of energy. But if you have special light bulbs called CFLs, you don't always have to turn them off. Turning them on and off too many times shortens their lifespans. You should turn them off if you'll be gone for 15 minutes of more. If you'll be right back, you can leave them on.

Coal is king, but not everywhere. In the United States, coal makes 39% of our electricity. It's burned in a power plant, and the heat is used to boil water. The steam moves a turbine and generates electricity. In West Virginia, over 90% of the electricity is generated from coal. But in California, only 1% of electricity is generated from this fossil fuel.

Daylight saving time is good for the planet. When we turn our clocks forward each spring, we move an hour of daylight toward the end of the day. In 2008, we had four extra weeks of Daylight Saving Time. Scientists studied how much energy we saved. Turns out, we saved 0.5% of electricity. Even though that sounds small, it's actually 1.3 billion kilowatt-hours. That's how much electricity 100,000 houses use in a whole year.

Every state uses hydropower for electricity. A flowing river is powerful. We can use the flow to make electricity. Ancient Greeks built water wheels to grind grain thousands of years ago. Today, every state uses hydropower, which is electricity from the flow water. In Washington State, 70% of the electricity comes from hydropower. Hydropower plants are inside dams, like the Hoover dam. Some places don't build dams. They use just part of a river to make electricity.

The United States is a world leader in wind. Wind has been a source of renewable energy since the invention of the windmill thousands of years ago. Today's wind power is made from big wind turbines. They're over 300 feet tall. Some have 8,000 parts. Along with China, Germany, Spain, and others, the United States is using wind to make lots of electricity.

The first solar powered satellite is still in orbit. The sun gives us lots of energy everyday. It hits us with 10,000 times the world's total energy use. The space industry has used solar power since the 1960s. It's great for spacecraft. Vanguard 1 was the first spacecraft to use solar cells. It's the oldest artificial satellite still in orbit around Earth.

We can get energy from trash. All that waste we flush down the toilet and put in our trashcans doesn't have to go to, well, waste! When waste breaks down, it can release methane, a natural gas. We can trap that gas and use it to make electricity. This is also helpful because methane is a greenhouse gas. If we use it, we keep it out of the atmosphere. This is great for the environment.

Electric vehicles are great, but not everywhere. Cars that run on electricity instead of gas don't release pollution. But when you charge the car at home, where does that electricity come from? If the electricity comes from renewable sources, electric cars are great for the environment. But if you charge a car with electricity made from coal, it's not as good. The car doesn't pollute, but the power plant that charges that car does.

We need better batteries. You might be surprised, but batteries need a lot of work. They don't store enough energy. For us to use solar power and wind power, we need to be able to store a lot of energy. That way, we can still have electricity on cloudy days with no wind. Lots of researchers are working to make better batteries that last longer and hold more energy.

We measure energy in BTUs. When we talk about energy, we all need to use the same unit to compare numbers. Just like we might use feet or meters to talk about length, we need a unit for energy. The standard unit of energy is called the BTU. That stands for British Thermal Unit. It's the amount of energy needed to raise the temperature of a pound of water by one degree Fahrenheit. When you burn a four-inch kitchen match, it releases about 1 BTU of energy.

What Is A Desert?

21 May, 2023

Approximately one-third of the Earth's land surface is desert, arid land with meager rainfall that supports only sparse vegetation and a limited population of people and animals. Deserts stark, sometimes mysterious worlds have been portrayed as fascinating environments of adventure and exploration from narratives such as that of Lawrence of Arabia to movies such as "Dune." These arid regions are called deserts because they are dry. They may be hot, they may be cold. They may be regions of sand or vast areas of rocks and gravel peppered with occasional plants. But deserts are always dry.

Deserts are natural laboratories in which to study the interactions of wind and sometimes water on the arid surfaces of planets. They contain valuable mineral deposits that were formed in the arid environment or that were exposed by erosion. Because deserts are dry, they are ideal places for human artifacts and fossils to be preserved.

Deserts are also fragile environments. The misuse of these lands is a serious and growing problem in parts of our world.

There are almost as many definitions of deserts and classification systems as there are deserts in the world. Most classifications rely on some combination of the number of days of rainfall, the total amount of annual rainfall, temperature, humidity, or other factors. In 1953, Peveril Meigs divided desert regions on Earth into three categories according to the amount of precipitation they received. In this now widely accepted system, extremely arid lands have at least 12 consecutive months without rainfall, arid lands have less than 250 millimeters of annual rainfall, and semiarid lands have a mean annual precipitation of between 250 and 500 millimeters. Arid and extremely arid land are deserts, and semiarid grasslands generally are referred to as steppes.

How The Atmosphere Influences Aridity

We live at the bottom of a gaseous envelope since the atmosphere is bound gravitationally to the planet. The circulation of our atmosphere is a complex process because of the Earth's rotation and the tilt of its axis. The Earth's axis is inclined 231/2° from the ecliptic, the plane of the Earth's orbit around the Sun. Due to this inclination, vertical rays of the sun strike 231/2° N. latitude, the Tropic of Cancer, at summer solstice in late June. At winter solstice, the vertical rays strike 23 1/2° S. latitude, the Tropic of Capricorn.

In the Northern Hemisphere, the summer solstice day has the most daylight hours, and the winter solstice has the fewest daylight hours each year. The tilt of the axis allows differential heating of the Earth's surface, which causes seasonal changes in the global circulation. On a planetary scale, the circulation of air between the hot Equator and the cold North and South Poles creates pressure belts that influence the weather. Most of the nonpolar deserts lie within the two trade winds belts. Air warmed by the sun rises at the Equator, cools as it moves toward the poles, descends as cold air over the poles, and warms again as it moves over the surface of the Earth toward the Equator.

This simple pattern of atmospheric convection, however, is complicated by the rotation of the Earth, which introduces the Coriolis Effect. To appreciate the origin of this effect, consider the following. A stick placed vertically in the ground at the North Pole would simply turn around as the Earth rotates. A stick at the Equator would move in a large circle of almost 40,000 kilometers with the Earth as it rotates.

The Coriolis Effect illustrates Newton's first law of motion: a body in motion will maintain its speed and direction of motion unless acted on by some outside force. Thus, a wind traveling north from the equator will maintain the velocity acquired at the equator while the Earth under it is moving slower. This effect accounts for the generally east-west direction of winds, or streams of air, on the Earth's surface. Winds blow between areas of different atmospheric pressures. The Coriolis Effect influences the circulation pattern of the Earth's atmosphere. In the zone between about 30° N. and 30° S., the surface air flows toward the Equator and the flow aloft is poleward. A low-pressure area of calm, light variable winds near the equator is known to mariners as the doldrums.

Around 30° N. and S., the poleward flowing air begins to descend toward the surface in subtropical high-pressure belts. The sinking air is relatively dry because its moisture has already been released near the Equator above the tropical rain forests. Near the center of this high-pressure zone of descending air, called the "Horse Latitudes," the winds at the surface are weak and variable. The name for this area is believed to have been given by colonial, sailors, who, becalmed sometimes at these latitudes while crossing the oceans with horses as cargo, were forced to throw a few horses overboard to conserve water.

The surface air that flows from these subtropical high-pressure belts toward the Equator is deflected toward the west in both hemispheres by the Coriolis Effect. Because winds are named for the direction from which the wind is blowing, these winds are called the northeast trade winds in the Northern Hemisphere and the southeast trade winds in the Southern Hemisphere. The trade winds meet at the doldrums. Surface winds known as "westerlies" flow from the Horse Latitudes toward the poles. The "westerlies" meet "easterlies" from the polar highs at about 50-60° N. and S. Near the ground, wind direction is affected by friction and by changes in topography. Winds may be seasonal, sporadic, or daily. They range from gentle breezes to violent gusts at speeds greater than 300 kilometers/hour.

Where Deserts Form

Dry areas created by global circulation patterns contain most of the deserts on the Earth. The deserts of our world are not restricted by latitude, longitude, or elevation. They occur from areas close to the poles down to areas near the Equator. The People's Republic of China has both the highest desert, the Qaidam Depression that is 2,600 meters above sea level, and one of the lowest deserts, the Turpan Depression that is 150 meters below sea level.

Deserts are not confined to Earth. The atmospheric circulation patterns of other terrestrial planets with gaseous envelopes also depend on the rotation of those planets, the tilts of their axes, their distances from the sun, and the composition and density of their atmospheres. Except for the poles, the entire surface of Mars is a desert. Venus also may support deserts.

Impacts Of Coal Mining

20 May, 2023

Coal is our most abundant “fossil fuel”. China is now the chief coal producer, followed by the United States. Other major coal producers are Australia and India. Five countries – China, the United States, India, Japan and Russia – account for more than 75% of worldwide coal consumption.

The US has more coal than the rest of the world has oil. There is still enough coal underground in the United States alone to provide energy for the next 200 to 300 years. But coal is far from a perfect fuel. Trapped inside coal are traces of impurities like sulfur and nitrogen. When coal burns, these impurities are released into the air.

While floating in the air, these substances can combine with water vapor (for example, in clouds) and form droplets that fall to earth as weak forms of sulfuric and nitric acid – scientists call it “acid rain.” There are also tiny specks of minerals, including common dirt, mixed in coal. These tiny particles don't burn and make up the ash left behind in a coal combustor. Some of the tiny particles also get caught up in the swirling combustion gases and, along with water vapor, form the smoke that comes out of a coal plant's smokestack.

Also, coal, like all fossil fuels, is formed out of carbon. All living things, even people, are made up of carbon. But when coal burns, its carbon combines with oxygen in the air and forms carbon dioxide. Carbon dioxide is a colorless, odorless gas, but in the atmosphere, it is one of several gases that can trap the Earth's heat. Many scientists believe this is causing the Earth's temperature to rise, and this warming could be altering the Earth's climate.

Threats To Wildlife From Coal Mining

Surface mining of coal is the method resorted to by the industry when coal deposits are found just below the Earth's surface. This happens to be the most used mining methodology of coal world over and has a direct and negative effect on ecosystems, environment and wildlife of places where such activity is carried out.

Excavation of the soil and heaping of spoils damages the Earth's surface beyond repair and causes decimation and displacement of wildlife species. It's worse for sedentary species like reptiles, small mammals, beavers and burrowing rodents, all of whose primary habitat is the Earth's surface.

Pollution of aquatic habitats is another outcome of surface mining for coal. Wastes and chemicals from it trickle and seep into streams, rivers and underground water-bodies. As a result, effects are manifested in places that are far away from mining sites. Most damaging are the kinds of chemicals pumped into the ground through pipes – mercury, methyl-mercury, cyanide and arsenic.

Mercury contamination is one of the most detrimental outcomes of coal mining. In the North-east mountain ranges of the US, it's been known to contaminate fresh-water lakes and in turn affect fish and fish-eating birds while damaging their neurological and reproductive systems. Studies show that 92 species from 11 North-Eastern states from Maine to Virginia are vulnerable to mercury contamination.

The wetlands that support a vast array of bird-life are especially open to one of the worst forms of pollution – methyl-mercury poisoning. Air pollution arising out of coal mining can quickly acidify water bodies. It hastens the process by which bacteria convert inorganic mercury from coal into organic methyl-mercury. Bogs, coastal marshes, beaver ponds, foggy mountaintops and forest floors are all absorbers of methyl-mercury. From such wetlands, it permeates into terrestrial grounds and this can corrupt an entire food web. Biomagnification takes over, and with each step of the food chain concentrations of mercury rise. This happens when creatures in these wet habitats feed on plant debris containing mercury, allowing it to enter terrestrial food sources. Rusty blackbirds and Saltmarsh sparrows have shown the highest levels of mercury contamination. Mercury poisoning of Virginia water-bodies threaten to hamper the Saltmarsh sparrow's ability to choose safe nesting sites.

Small traces of methyl-mercury, that were previously ignored as being harmful, have now revealed the adverse effects it can have on reproduction of species. Just a minuscule amount of 1.2 parts per million of methyl-mercury found in the blood of the Carolina wren have accounted for a 20 percent drop in their reproductive capacities. The wrens are scavengers and glean the forest floors for spiders, which too are contaminated.

Most surprising is the case of the tiny Dome Island in the middle of the pristine Lake George in the uplands of New York State. This untouched 16-acre island in the Adirondack region is considered to be a conservation gem and is home to species of songbirds like the red-eyed vireos, black-capped chickadees and song sparrows that flutter among ancient cedars, beech, hickory and oak. Shockingly, these birds have revealed the highest concentrations of mercury in the North-east region. They are victims of airborne mercury pollution. Almost 50 tons of neurotoxins are belched into the atmosphere annually by coal-based power plants in the US. This “atmospheric deposition” of mercury is a global hazard, but is more pronounced in the bio-diversity rich hotspots that lie downwind to coal-burning epicenters of Ohio, Illinois, Pennsylvania and Indiana.

Wanton mining practices elsewhere in the world have results in coal fires that can burn for decades, as in the case of numerous mines in Eastern India. It releases fly ash into the atmosphere, along with smoke full of toxic chemicals and greenhouse gasses. Coal mine methane, a greenhouse gas emitted by mining of the mineral, is 20 times more toxic than carbon dioxide.

In China, even though 95 percent of the mines are underground, the threat of a methane outburst always looms.

Other problems that have environmental consequences are coal storage piles or waste piles. These afflict countries like China, Russia, the US, Indonesia, Australia and South Africa in a considerable way.

The biggest threat to the environment comes from countries with huge reserves of coal. A fear for these countries is there could be alternative sources of energy in the future that could replace a fossil-fuel like coal. So the idea of mining and finishing whatever stocks of coal remain before such a replacement happens weighs heavily on the minds of policy makers. Hence the near-frenetic activity in coal mining in places like India and China. Also, both depend heavily on this mineral to make-up for the huge shortfall in oil to meet their ever-growing energy needs.

Coal Impact On Climate

Coal is an abundant fuel source that is relatively inexpensive to produce and convert to useful energy. However, producing and using coal impacts the environment.

Climate change is one of the greatest environmental challenges we face. Climate impacts affect the entire planet. Unchecked carbon pollution leads to long-lasting changes in our climate, such as rising global temperatures; rising sea level; changes in weather and precipitation patterns; and changes in ecosystems, habitats and species diversity. These changes threaten human and wildlife health and welfare.

Environmental risks include more heat waves and drought; worsening smog (also called ground-level ozone pollution); increasing the intensity of extreme events, like hurricanes, extreme precipitation and flooding; and increasing the range of ticks and mosquitoes, which can spread disease such as Lyme disease and West Nile virus.

Overwhelmingly, the best scientists in the world are telling us that our activities are causing climate change – based on troves of data and millions of measurements collected over the course of decades on land, in air and water, at sea and from space.

Emissions From Burning Coal

Most of the coal consumed is used as a fuel to generate electricity. Burning coal produces emissions that adversely affect the environment and human health.

There are several principal emissions resulting from coal combustion:

Sulfur dioxide (SO2), which contributes to acid rain and respiratory illnesses
Nitrogen oxides (NOx), which contribute to smog and respiratory illnesses
Particulates, which contribute to smog, haze, and respiratory illnesses and lung disease
Carbon dioxide (CO2), which is the primary greenhouse gas emission produced from the burning of fossil fuels (coal, oil, and natural gas)
Mercury and other heavy metals, which have been linked to both neurological and developmental damage in humans and other animals
Fly ash and bottom ash, which are residues created when coal is burned at power plants. Fly ash is generally stored near power plants or placed in landfills. Pollution leaching from ash storage and landfills into groundwater and the rupture of several large impoundments of ash are environmental concerns.

Coal And Water

Coal not only pollutes our skies and fuels climate change, it also deprives us of our most precious resources: water. The world’s rapidly dwindling freshwater resources could be further depleted if plans for hundreds of new coal power plants worldwide go ahead, threatening severe drought and competition.

If all the current proposed coal plants are allowed to be built, the water consumed by coal power plants around the world would almost double. Globally, coal power plant units already consume enough water to meet the basic water needs of 1 billion people. A quarter of the proposed new coal plants are planned in regions already running a freshwater deficit, where water is used faster than it is naturally replenishing.

Coal is one of the most water-intensive methods of generating electricity. According to the International Energy Agency, coal will account for 50% of the growth in global water consumption for power generation over the next 20 years. Research shows that if the proposed coal plants come online, their consumption of water will increase by 90%.

Public Lands Mismanaged

America has more coal than any other fossil fuel resource. The United States also has more coal reserves than any other single country in the world. In fact, just over 1/4 of all the known coal in the world is in the US. The United States has more coal that can be mined than the rest of the world has oil that can be pumped from the ground. Currently, coal is mined in 26 of the 50 states.

The Bureau Of Land Management (BLM) has responsibility for coal leasing on approximately 570 million acres where the coal mineral estate is owned by the Federal Government. The surface estate of these lands could be controlled by BLM, the United States Forest Service, private land owners, state land owners, or other Federal agencies. BLM receives revenues on coal leasing at three points: a bonus paid at the time BLM issues the lease; an annual rental payment of $3.00 per acre or fraction thereof; and royalties paid on the value of the coal after it has been mined. The Department of the Interior and the state where the coal was mined share the revenues.

Surface mines (sometimes called strip mines) are the source of about 65% of the coal that is mined in the US. These mining operations remove the soil and rock above coal deposits, or seams. Mountaintop removal and valley fill mining has affected large areas of the Appalachian Mountains in West Virginia and Kentucky. In this form of coal extraction, the tops of mountains are removed using explosives. As a result of this technique, the landscape is changed, and streams may be covered with rock and dirt. The water draining from these filled valleys may contain pollutants that can harm aquatic wildlife downstream. Although mountaintop mining has existed since the 1970s, its use became more widespread and controversial beginning in the 1990s.

Underground mines have less of an impact on the environment compared to surface mines. The largest impact of underground mining may be the methane gas that must be vented out of mines to make the mines a safe place to work. Methane is a strong greenhouse gas, meaning that on an equal-weight basis its global warming potential is much higher than other greenhouse gases. Surface mines contributed about 2% of total US methane emissions. The ground above mine tunnels can also collapse, and acidic water can drain from abandoned underground mines.

Using public lands for coal mining poses a significant threat to natural heritage. Coal mining dramatically alters the landscape, destroys wildlife habitat, causes erosion, and leads to the deterioration of drinking water.

Time For Changes

The ecological devastation from coal activities is disturbing. Action needs to be taken. Innovative technologies for improved mining and processing must be a priority to respond better to global environmental challenges, while governments and private sectors need to shift to alternative energy sources.

What Is Ocean Acidification?

19 May, 2023

Ocean acidification refers to a reduction in the pH of the ocean over an extended period time, caused primarily by uptake of carbon dioxide (CO2) from the atmosphere.

For more than 200 years, or since the industrial revolution, the concentration of carbon dioxide (CO2) in the atmosphere has increased due to the burning of fossil fuels and land use change. The ocean absorbs about 30 percent of the CO2 that is released in the atmosphere, and as levels of atmospheric CO2 increase, so do the levels in the ocean.

When CO2 is absorbed by seawater, a series of chemical reactions occur resulting in the increased concentration of hydrogen ions. This increase causes the seawater to become more acidic and causes carbonate ions to be relatively less abundant.

Carbonate ions are an important building block of structures such as sea shells and coral skeletons. Decreases in carbonate ions can make building and maintaining shells and other calcium carbonate structures difficult for calcifying organisms such as oysters, clams, sea urchins, shallow water corals, deep sea corals, and calcareous plankton.

Pteropods are small calcifying (or shelled) organisms that live as zooplankton in the water column and are an important prey species for many fish. Changes in ocean chemistry can break down their calcium carbonate shell, ultimately leaving the marine food web at risk.

These changes in ocean chemistry can affect the behavior of non-calcifying organisms as well. Certain fish's ability to detect predators is decreased in more acidic waters. When these organisms are at risk, the entire food web may also be at risk.

Ocean acidification is affecting the entire world’s oceans, including coastal estuaries and waterways.

What Are Wildlands?

18 May, 2023

Wilderness or wildlands are natural places on our planet that have not been significantly modified by humans. These last, truly wild places that have not been developed with industry, roads, buildings and houses are critical for the survival of many plant and animal species. They also provide humans with educational and recreational opportunities, and are deeply valued for aesthetic, cultural, moral and spiritual reasons.

Some wildlands are protected, preserving natural areas for humans, animals, flora and fauna. Others are dissapearing at alarming rates, and simply drawing lines around specific areas is not enough. All of our planet is intricately connected. What happens outside a specific wilderness area affects what happens inside it.

Many wildlife habitats have become fragmented due to human development. Without the protection of vast expanses of wildlands to meet the minimum requirements of the largest, most widely roaming members of the ecosystem, they may dwindle or vanish forever. The loss of any species effects the entire ecosystem.

Biomes, or ecosystems, are large regions of the planet with shared characteristics such as climate, soils, plants and animals. Climate is an important factor that shapes the nature of an ecosystem, as well as precipitation, humidity, elevation, topography and latitude.

The five major biomes include aquatic, desert, forest, grassland and tundra biomes. Each biome also includes numerous types of sub-habitats.

By protecting and preserving ecosystems, we protect and preserve plant and animal species...including our own species.

Urban Ecosystems

17 May, 2023

Around half of the planet's population now lives in a city. The move towards urban living has increased city sizes tremendously with an enormous impact on ecosystems. Once wild landscapes have been transformed into urban centers, changing animal habitats both inside and outside the areas.

Animals in these areas have had to adapt. They have learned to create new homes within their artificial environments. They have also discovered new food sources, including waste created by humans. Food chains of numerous species have been altered.

Urban areas range from fully urban with little green space and mostly covered by paving or buildings, to suburban areas with gardens and parks. Different types of urban areas support different kinds of wildlife. Some animals find shelter in city parks, trees and water sources. Some live inside the city; others just outside the urban habitat.

Insects, reptiles and rodents make nests inside buildings in small gaps and crevices to find shelter from the elements and protection from predators. Birds nest on buildings. Some animals live under homes and buildings. Some make homes in city sewer systems.

Animals have cleverly adapted to their changing world. Some city animals have become nocturnal, using city lights to aid in finding prey. Feral dogs have learned to use subway systems. Urban monkeys and penguins raid human homes to take food. Some steal fruit from vendors. Older deer learn to look both ways before crossing streets. Birds flock to city centers to snack on the food dropped in the streets.

Numerous threats for urban animals include traffic, litter, pollution, noise pollution, bright lighting and lack of space.

It is important to reserve space within urban environments for wildlife, and to conserve natural environments outside cities.

Does Coral Make A Good Gift?

17 May, 2023

Corals are popular as souvenirs, for home decor and in costume jewelry, yet corals are living animals that eat, grow, and reproduce. It takes corals decades or longer to create reef structures, so leave corals and other marine life on the reef.

Corals have long been popular as souvenirs, for home decor, and in jewelry, but many consumers are unaware that these beautiful structures are made by living creatures. Fewer still realize that corals are dying off at alarming rates around the world.

Coral reefs are some of the most biologically rich and valuable ecosystems on Earth, but they are threatened by an increasing array of impacts—primarily from global climate change, unsustainable fishing, and pollution. Strong consumer demand for coral, heightened over the holiday season, is another factor that is contributing to the decline of coral reefs. Each year, the U.S. imports tons of dead coral for home decorations and curios. Most of these corals are shallow-water species.

The U.S. is also the world's largest documented consumer of Corallium, red and pink corals often used to create jewelry. Finished pieces of jewelry and art crafted from this type of coral can fetch anywhere between $20 and $20,000 in the marketplace. Continued consumer demand is contributing to the decline of these delicate corals around the world.

Commercial harvesting to satisfy the demand for coral jewelry has reduced colony size, density, and age structure of Corallium over time. Harvesting is also lowering the reproduction capability of this species and is decreasing its genetic diversity. Research indicates that removal of red and pink corals for the global jewelry and art trade is also leading to smaller and smaller Corallium in the wild.

Corals grow very slowly, are extremely long-lived, and take years to reach maturity. It takes corals decades or longer to create reef structures. Once coral is harvested—especially when it's extracted at a young age—surrounding coral beds often do not recover. That's why it's best to leave corals and other marine life on the reef.

Remember: corals are already a gift. Don't give them as presents.

Saving Gorillas From Extinction

16 May, 2023

Descendants of monkeys found in Africa and Arabia, gorillas are herbivorous apes found only in the African continent. There are two broad species of this African animal. One is the Eastern gorilla and the other the Western gorilla. The Eastern gorilla has two subspecies. The Western gorilla also has two subspecies. All gorilla species are listed as endangered by the International Union for Conservation of Nature (IUCN).

Gorilla populations have been greatly reduced by habitat loss, disease and poaching. Protecting gorilla populations has proved difficult due to the vast dense areas in which they live. Conservation efforts by governmental and non governmental organizations are desperately trying to save gorillas from extinction.

Eastern Gorillas

The Eastern Lowland gorilla, or Grauer's gorilla, is mostly found on the plains and lower slopes of the Virunga volcanic mountains of Central Africa. This habitat area of the ape entirely falls in the Eastern part of the Democratic Republic of Congo (DRC). This huge, hairy ape, with a shiny black coat, can measure up to 5 feet-6 inches while standing to its full height. They weigh as much as 550 lbs or 250 kilograms. The population of this subspecies has been reduced from around 5,000 in 2004 to only 3,800 .

The mountain gorillas are an endangered species exclusively dwelling in the Rwandan half of the Virunga volcanic mountains at altitudes of 7,000 to 14,000 feet. Like their Eastern lowland cousins, they have jet black hair but with a slight bluish tinge. While standing totally erect, the mountain gorilla is an impressive sight. Reaching a height of 6 feet-2 inches, it has an enormous arm span of 8 feet-6 inches and can weigh almost 500 lbs. There are only 880 of this sub-species left. Mountain gorillas were popularized by the film "Gorillas of the Mist" that portrayed the life of Diane Fossey, who spent two intrepid decades in the Rwandan mountains studying and fighting for the preservation of the apes.

For the mountain gorillas, major threats come from forest clearance and degradation as poor Rwandans desperately try to eke out a living. Clearing out land for agriculture and deforestation for firewood also puts a lot of pressure on the natural resources of the region and eventually on the habitat of these rare apes.

Western Gorillas

The Western lowland gorilla's habitat spans plains, forests and swamps of countries like Angola, Cameroon, Central African Republic, DRC, Equatorial Guinea and Gabon. They are smaller in size to the Eastern gorillas and have longer black hair covering almost their entire body. They number almost 125,000 and are inhumanely kept captive in zoos all over the world for human entertainment and profit.

The Cross River gorilla is a species found essentially in the Cross-Niger transition forests on the western half of the Cross River flowing into South-western Nigeria. Most of these hilly forests fall in Cameroon. They are a distinctive sub-species with short body hair and shorter skulls, smaller palates and smaller cranial vaults compared to the Western lowland gorillas.

The Western gorillas, that inhabit as many as 11 countries of Western Africa, are under threat from logging, hunting, disease and even trigger-happy militia. They often come into direct confrontation with man. Many of them are killed for their meat by impoverished and hungry tribesmen. Apes can be seen as a nuisance, too. Forced to move away from a shrinking habitat, the animals raid crops. A single group of gorillas can easily destroy an entire harvest. Villagers feel they have no recourse but to kill the animals. Only 250 to 300 of these creatures are left, making them one of the most endangered animals on the planet.

Threats To Gorillas

The greatest threat to gorillas is human poverty. They inhabit countries which are among the poorest in the world but with a high density of human population.

Being closely related to the humans anatomically, apes are susceptible to disease as much as man. Not just from poachers and militia groups, but exposure to well-meaning humans like tourists, conservationists, scientists, rangers and local communities poses a threat. Gorillas have been known to succumb to skin diseases and respiratory disorders. Outbreaks of Ebola can take many more gorilla lives than humans.

Poaching of infant mountain gorillas to cater to the illicit animal trade became a common threat in the early 2000s. Civil unrest also took a toll on the apes. The Rwandan genocide of the 1990s, and the Angolan wars of the 1980s, had an unsettling effect on the movement and habitat of gorillas. Large movements of refugees fleeing unrest, debris left behind by them, and warring militias posed major threats.

Weak local governments, virtual absence of forest regulations or conservation policies, and impoverished and disenchanted local communities all pose serious challenges to the survival of the apes.

Saving Gorillas

The only ray of hope for saving gorillas from extinction is conservation. A gradual rise in the population of mountain gorillas has taken place thanks to conservation programs. From the lowest point in 1980 when its numbers were just 254, it has now grown to 880.

Similar efforts in the Campo Ma’an National Park in Cameroon and Cross River National Park of Nigeria has held some hope for the tiny population of Cross-river gorillas dwelling there. Recent surveys show that the counts for these apes have not gone below the 300 mark.

But applying conservation measures to the lowland gorillas will be far more challenging given their wider habitat coverage. Efforts must be made to save the apes before it's too late.

Sea Levels Are Rising

16 May, 2023

There is strong evidence that global sea level is now rising at an increased rate and will continue to rise during this century. A warming climate can cause seawater to expand and ice over land to melt, both of which can cause a rise in sea level.

While studies show that sea levels changed little from AD 0 until 1900, sea levels began to climb in the 20th century.

The two major causes of global sea-level rise are thermal expansion caused by the warming of the oceans (since water expands as it warms) and the loss of land-based ice (such as glaciers) due to increased melting.

First, as the oceans warm due to an increasing global temperature, seawater expands—taking up more space in the ocean basin and causing a rise in water level.

The second mechanism is the melting of ice over land, which then adds water to the ocean.

Records and research show that sea level has been steadily rising at a rate of 0.04 to 0.1 inches per year since 1900. Since 1992, new methods of satellite altimetry (the measurement of elevation or altitude) indicate a rate of rise of 0.12 inches per year. This is a significantly larger rate than the sea-level rise averaged over the last several thousand years.

Destructive Dams

15 May, 2023

Rivers are essential to the health of the Earth. They are among the most diverse ecosystems on the planet. Rivers can be degraded by many human activities, including pollution, channelization and watershed destruction – but dams have the greatest impacts.

Dams are barriers that hold back water and raise the water level, resulting in a reservoir. They are constructed for electric production, flood control, water supply and irrigation. Despite their benefits to humans, dams are destroying riparian ecosystems.

With an ever-increasing demand for energy and water, the amount and size of reservoirs is increasing around the world. Environmental consequences are outnumbering the benefits of dams – which degrade water quality, disrupt flows, affect the movement of sediment and nutrients, destroy habitats, and reduce recreational options. Dam reservoirs also slow and widen rivers, raising their temperatures. Water quality is degraded, and non-native species invade the ecosystems.

Dam Devastation

There is no such thing as “clean hydro power” on a large-scale. Hydro dams result in fluctuations in downstream flows, dewater stream channels, and cause the death and reduction of aquatic species.

Dams eliminate habitats both in the reservoirs and in the river below. Migratory fish may not survive their downstream travel, faced with numerous man-made obstacles. The return trip is even more challenging. Dams also contribute to global warming. Within the last 20 years, large dam methane emissions have equaled about the equivalent of 7.5 billion tons of carbon dioxide.

Degraded water quality results when organic materials from in and outside rivers build up behind dams. When the movement of sediment is disrupted, materials build up at the mouth of the reservoir, starving downriver ecosystems of vital ingredients. These backed-up materials, when decomposing, consume large amounts of oxygen, often resulting in algae blooms that create oxygen-starved “dead zones”. Temperatures of the water are affected, threatening marine life. When the oxygen-deprived, temperature affected water is released, downstream ecosystems also suffer.

Dam Development Out of Control

The United States has built thousands of dams, while some countries are just beginning to construct dams and are doing so at a disturbingly fast rate. Withing the next 30 years, thousands of new dams are expected to be constructed globally. Seventy percent of rivers impacted by the new dam construction are home to the greatest diversity of fish species on the planet. The irreversible destruction caused by these dams will affect both people and wildlife.

The Three Gorges Dam in China, built on the Yangtze River in 2003, supports a catchment area of almost 400,000 square miles. The Hubei region in which the dam is situated is home to 6,300 species of plants, 57 percent of which are endangered. This Central Yangtze region also supports 378 species of freshwater fish, 280 species of mammals and 166 species of reptiles. The project has severely affected temperatures of water and flow patterns that has taken a toll on aquatic life surrounding it. Instances of rotating turbine blades injuring fish abound. The most serious case of wildlife abuse has been the complete extinction of the Baiji, or Chinese river, dolphin.

Destruction of wetlands in the wake of the Three Gorges project has driven away tens and thousands of the rare Siberian crane that come to spend winters there. Today, only around 3,000 of these majestic birds are to be sighted in these wetlands. The Yangtze sturgeon, a species of fish endemic to the waters of this region, have been nearly driven to extinction. To make matters worse for wildlife survival, the human population in the Yangtze River Basin has doubled in the last 50 years which resulted in more dams to cater to the energy and irrigation needs of probably the biggest concentration of human population in the world. The number of dams in China is now 80,000, a majority of which have been constructed after 1949. What this has done to ecosystems and the biodiversity it supports is unfathomable.

Similarly, hydro power projects on the Mekong, Congo and Amazon rivers have caused incalculable losses to the once rich biodiversity and wildlife abounding their catchment areas. Dam construction on the Xingu River, a tributary of the Amazon, threaten the existence of 50 species of fish unique to the waters of the lower Xingu.

Dams interfere with the natural water flow of rivers and cause intense harm to downstream flora and fauna. Dam projects on the Mekong River in South-East Asia are causing massive disruption to aquatic ecosystems the river supports. Nearly two-thirds of the freshwater fish are long-distance migratory species that travel downriver for spawning in the Lower Mekong. The construction of dams on the upper Mekong has blocked such migratory routes, causing a huge drop in the population of such fish. A massive reduction in commercial fish catch by as much as 30 percent is a poignant indicator of this.

The above are not just isolated instances; hundreds of them occur in various parts of the world. Forest areas totaling 9 million hectares have been submerged as a result of the 1,800-odd dams constructed between 1980 and 2000. Ecosystems supporting flora and fauna were obliterated overnight. Unlike humans, wild animals are incapable of being forewarned of impending floods and this creates panic among them. Wary of leaving their habitat, some of them simply drown and the more fortunate migrate to safer but unknown territories.

Canals or drainage for irrigation purposes can also act as obstructions to wildlife habitats; so can power lines cutting through forest patches. Dams also affect the biosphere by way of greenhouse emissions.

Nearly 500 dam projects are currently in the pipeline worldwide. This spells danger to the 4,000 unique species of fish in just three major rivers systems alone – the Amazon, the Mekong and the Congo. What lies in store in numerous other river systems of the world are the extinction of many fish and other aquatic species, the decimation of floodplains, wetlands and farmlands that support a vast array of bird life, and erosion of coastal deltas.

Dam Removal

As communities begin to realize that the environmental, economic, and cultural consequences of dams outweigh the benefits, dam removal is becoming a popular occurrence. Removing dams helps to restore ecosystems and river flow for wild animals while restoring natural nutrient flow and sediment and nutrient flow.

Dam removal can also eliminate safety issues in a community, protect wetlands and coastal beaches, improve community water quality, restore recreational opportunities, and save taxpayer money.

Dams Are Not The Solution

To meet the needs of a burgeoning human population, plundering of natural resources and destruction of the world's ecosystem have been resorted to, posing a grievous threat to the future of Earth's wildlife. Among the millions of pinpricks inflicted on nature by man, one has been the wanton construction of dams.

Despite the construction of such a huge multitude of dams, over a billion people still are deprived of clean drinking water. Two billion are bereft of basic sanitation, and a similar number still lack electricity.

Scientific studies have shown that dams are not the green, clean and economical source of electricity they are made out be. For the sake of the world's dwindling wildlife population, governments and authorities must pay heed to their plight.

New technologies offer more environmentally responsible alternatives to dams. More efficient energy sources – including wind, solar, geothermal, tidal, wave and biomass options – can help eliminate our dependence on dams. Residential, commercial, and agricultural water reduction is also an effective solution to reducing the need for dams.

Interacting With Marine Mammals

15 May, 2023

Viewing and interacting with marine mammals in the wild attracts sufficient numbers of people. A small industry has grown from it. Well intentioned or not, this industry and the public it serves frequently do not take into account the well-being of the animals they view. Marine mammal specialists and advocates have sufficient cause to be concerned.

TYPES OF INTERACTION

Marine mammals in their natural habitat attract many tourists. Anyone who approaches a wild animal to touch, feed, or pose for photographs with it may be guilty of unintentional harassment. Sometimes the harassment is a matter of indifference, such as the many people on some parts of the west coast who frequently disregard posted signs and walk among elephant seals "hauled out" (who have hauled themselves out) on beaches.

Jet-skiing, kayaking, boating, and similar aquatic recreational activities may harass marine mammals in the wild by pursuing, annoying or tormenting them. Scuba or snorkel divers may find it "fun" to harass manatees by swimming around them or touching them, an example of intentional wildlife abuse by humans.

Many commercial tour operations regularly feed the wild animals to encourage them to approach their vessels, then offer tourists an opportunity to photograph, feed, pet or swim with marine mammals. Bottlenose dolphins in the southeast are the most affected animals in such activities.

RISK TO ANIMALS & HUMANS

These human interactions threaten the health and well-being of marine mammals. Possible consequences are driving them from their preferred habitat; disrupting their social groups; poisoning them with inappropriate food; and exposing them to fish hooks and boat propellers.

Wildlife fed by humans often become habituated to the free handout and, unwilling or unable to forage for food, develop the unnatural behavior of begging. This is crucial when young animals need to learn foraging skills.

Many people have been seriously injured when marine mammals who have become conditioned to being fed by humans have behaved aggressively toward them. Medical attention is usually required, and sometimes even hospitalization. Animals who behave aggressively in these situations are usually perceived as "nuisance animals," thus opening the door to animal "control" that may mean death to the animals.

ILLEGAL ACTIVITIES

The Marine Mammal Protection Act (MMPA) clearly sets forth the law in interactions with wild marine mammals. Interactions such as those mentioned above may constitute harassment and carry civil and criminal penalties, including fines as high as $20,000 and up to a year in jail. The MMPA defines harassment as "any act of pursuit, torment, or annoyance which has the potential to injure a marine mammal or marine mammal stock in the wild; or has the potential to disturb a marine mammal or marine mammal stock in the wild by causing disruption of behavioral patterns, including, but not limited to, sheltering."

Many marine mammals are endangered or threatened. Human interaction may therefore also be a violation of the Endangered Species Act.

WHAT YOU CAN DO

For the animals' sake, and for your safety, please don't feed, swim with, or harm marine mammals.

Share your knowledge with others. Encourage friends and family not to patronize boat operators and resorts that promote marine mammal encounter programs.

Ask the National Marine Fisheries Service to provide increased manpower and money to enforce the federal regulations prohibiting feeding and harassment of marine mammals. Write to: National Marine Fisheries Service, Office of Protected Resources; 1315 East-West Highway, 13th Floor; Silver Spring, MD, 20910.

To report a violation of the Marine Mammal Protection Act, call: NOAA Fisheries Enforcement Hot Line: 1-800-853-1964.

RESPONSIBLE MARINE MAMMAL VIEWING

The significant growth in whale-watching and other marine-mammal viewing increases the likelihood of a threat to the animals. The National Marine Fisheries Service has therefore set forth guidelines for land or water based viewing. If you choose recreational activities in the marine environment, please keep this "Code of Conduct" in mind:

Remain at least 100 yards from marine mammals. Binoculars will ensure that you view at a safe distance. If a whale approaches within 100 yards of your vessel, put your engine in neutral and allow the whale to pass.

Because many watchers on many vessels have a cumulative effect, limit your observing time to one hour. Avoid approaching the animals when another vessel is near.

Whales should not be encircled or trapped between boats, or boat and shore.

Offering food, discarded fish, or fish waste is prohibited.

Do not touch or swim with marine mammals. Never attempt to herd, chase or separate groups of marine mammals or females from their young.

If your engine is not running, whales may not recognize your location. To avoid collisions, make noise, such as tapping the side of the boat.

Do not handle pups. "Hauled out" seal or sea lion pups may appear abandoned when the mother is feeding. Leave them alone.

When viewing hauled out seals or sea lions, try not to let them see, smell or hear you.

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