Sustaining Tropical Forests

19 Apr, 2018

Strategies for preserving tropical forests can operate on local to international scales. On a local scale, governments and non-governmental organizations are working with forest communities to encourage low-impact agricultural activities, such as shade farming, as well as the sustainable harvesting of non-wood forest products such as rubber, cork, produce, or medicinal plants. Parks and protected areas that draw tourists—ecotourism—can provide employment and educational opportunities for local people as well as creating or stimulating related service-sector economies.

On the national scale, tropical countries must integrate existing research on human impacts on tropical ecosystems into national land use and economic development plans. For tropical forests to survive, governments must develop realistic scenarios for future deforestation that take into account what scientists already know about the causes and consequences of deforestation, including the unintended deforestation that results from road-building, accidental fire, selective logging, and economic development incentives such as timber concessions and agricultural subsidies.

Scientists are encouraging the conservation community to re-consider the belief that vast, pristine parks and protected areas are the holy grail of forest conservation. Scientists using satellite and ground-based data in the Amazon demonstrated that far less “unfettered” deforestation occurred in recent decades within territories occupied and managed by indigenous people than occurred in parks and other protected areas. The deforestation in the protected areas resulted from a combination of illegal logging and devastating fires that raged through logging-damaged forests during drought. While some might argue that these losses could be prevented in the future through better enforcement of environmental laws, it may also be true that inhabited forest reserves are a more realistic strategy for preserving the majority of biodiversity in larger areas than parks alone can accomplish.

Finally, on the national and international scale, an increasing value in the global marketplace for products that are certified as sustainably produced or harvested—timber, coffee, soy—may provide incentives for landowners to adopt more forest-friendly practices, and for regional and national governments to create and enforce forest-preservation policies. Direct payments to tropical countries for the ecosystem services that intact tropical forest provide, particularly for carbon storage to offset greenhouse gas emissions, are likely to become an important international mechanism for sustaining tropical forests as more countries begin to seriously tackle the problem of global warming.

Sea Turtles Face Plastic Deluge Danger

19 Apr, 2018

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.

What Is A Desert?

19 Apr, 2018

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.

Saving Gorillas From Extinction

15 Apr, 2018

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.

What Are Wildlands?

15 Apr, 2018

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.

Affluent Countries Aren't Doing Enough For Wildlife

12 Apr, 2018

Human impact continues to have a devastating effect on the natural world, with wildlife species across the globe under threat from poaching, hunting and the consequences of climate change. Recent studies indicate that 59 percent of the world's largest carnivores and sixty percent of the largest herbivores are currently threatened with extinction.

Scores of species across the globe, including tigers, lions and rhinos, are at risk of extinction due to a plethora of threats imposed by mankind. We will lose many of these incredible species unless swift, decisive and collective action is taken by the global community.

Every country should strive to do more to protect its wildlife, but the richest countries, who can afford to do the most, are not doing enough. Less affluent countries are more committed to conservation of their large animals than richer ones. In comparison to the more affluent, developed world, biodiversity is a higher priority in poorer areas such as the African nations, which contribute more to conservation than any other region.

Researchers from Oxford's Wildlife Conservation Research Unit (WildCRU) have created a Mega-Fauna Conservation Index (MCI) of 152 nations to evaluate their conservation footprint. The benchmarking system evaluates three key measures: a) the proportion of the country occupied by each mega-fauna species that survives in the country (countries with more species covering a higher proportion of the country scoring higher); b) the proportion of mega-fauna species range that is protected (higher proportions score higher); c) and the amount of money spent on conservation - either domestically or internationally, relative to GDP.

The findings show that poorer countries tend to take a more active approach to biodiversity protection than richer nations. Ninety percent of countries in North and Central America and 70 percent of countries in Africa are classified as major or above-average in their mega-fauna conservation efforts.

Despite facing a number of domestic challenges, such as poverty and political instability in many parts of the continent, Africa prioritizes wildlife preservation and contributes more to conservation than any other region of the world. African countries make up four of the five top-performing mega-fauna conservation nations, with Botswana, Namibia, Tanzania and Zimbabwe topping the list. By contrast, the United States ranks nineteenth out of the twenty performing countries. Approximately one-quarter of countries in Asia and Europe are identified as significantly underperforming in their commitment to mega-fauna conservation.

Mega-fauna species are associated with strong 'existence values', where just knowing that large wild animals exist makes people feel happier. In some cases, such as the African nations, this link explains why some countries are more concerned with conservation than others. Larger mammal species like wild cats, gorillas and elephants play a key role in ecological processes as well as tourism industries, which are an economic lifeline in poorer regions.

The conservation index is intended as a call to action for the world to acknowledge its responsibility to wildlife protection. By highlighting the disparity in each nations' contributions it hopes to see increased efforts and renewed commitment to biodiversity preservation.

There are three ways countries can improve their MCI scores:

They can 're-wild' their landscapes by reintroducing mega-fauna and/or by allowing the distribution of such species to increase;
They can set aside more land as strictly protected areas;
And they can invest more in conservation, either at home or abroad.

Some of the poorest countries in the world are making the biggest investments in a global asset and should be congratulated. Some of the richest nations just aren't doing enough.

Why Habitats Matter

12 Apr, 2018

A habitat consists of the ecosystem or environment in which an animal, plant or other living organism has lived and evolved over a considerable period of time. A habitat provides all the necessary ingredients they need to survive - food, water, shelter, the right temperatures, resources to ward off possible predators, and the right environs for reproduction and avoiding disease.

Without a habitat, a creature is virtually homeless and faces certain death. The habitat is a complete and intricate network of dependability provided to a species or many species by nature. A decimation of a habitat could spell doom for the biodiversity thriving in it, be it animals, insects, plants and other organisms.

Causes Of Loss Of Habitat

Causes of habitat loss can be natural factors like climate changes or catastrophes such as flooding, earthquakes, storms, volcanoes or other geological changes. Habitat loss can also be man-made. Excessive exploitation and destruction of natural resources through logging, fishing, mining, oil and gas exploration, development, road construction, animal agriculture, callous disposal of industrial waste and the introduction of unwanted species all contribute in depleting or destroying the richness of habitats.

Fragmentation and alteration of natural habitats are also serious threats to ecostystems.

Habitat Loss And Endangered Species

85 percent of species on the IUCN's Red List are considered truly threatened by loss of their habitats. For endemic species, the ones that are only to be found in one particular kind of habitat uniquely suited to its survival, the challenge to ward off extinction is truly serious. When an endemic species' habitat is destroyed, it has no other ecosystem to fallback on like generalized species. In absence of a suitable habitat, death becomes imminent.

Habitats of many species could cover large areas and overlap. But for species with extremely low populations, habitats are specialized and small, making them susceptible to extinction. In the event of catastrophes, the genetic limitations of a threatened species make it almost impossible to survive. The lack of genetic diversity among critically endangered species also breeds reproductive failure.

Tools used to measure habitat size are more scaled towards those with large contiguous areas than smaller ones. In the 1970s and 1980s, the debate over whether a single large or several small reserves was the answer to optimum conversation ultimately saw the emergence of the former theory as the accepted premise that large-sized habitats proved better survival grounds than smaller habitats. Bigger habitats act as buffers to human disruptions and also facilitates migration and food gathering.

Habitat Conservation

Presently, conservation efforts are dictated by the habitat condition or status of an endangered species. Certain delicate ecosystems and bio-diversities warrant conservation endeavors to such a degree that they fall under the category of biodiversity "hotspots". Endemic wildlife and near-extinction species harbored by such ecosystems are the focus of intense conservation efforts. Much of the risk comes from human encroachment.

Nearly 34 places of the world have been identified as biodiversity hotspots. These cover almost 2.3 percent of the earth's surface, but have lost almost 70 percent of their original vegetation. Endemic to these hotspots are an astonishing 50 percent of the world's plant species, and 42 percent of animal species. Efforts to preserve such biodiversity zones are at the forefront of conservation endeavors.

But while around 98% of the Earth has less species diversity, these ecosystems need just as much help as areas with lots of biodiversity. In fact, some biodiversity "coldspots" are home to very rare plants and animals. Protecting these areas before too much destruction occurs prevents us from having to work backwards.

An Uphill Climb For Mountain Species

9 Apr, 2018

Mountains cover about 27 percent of Earth's surface. They inspire awe and cultural lore, and directly influence the patterns of settlement and movement by humans and wildlife. Despite some degree of protection due to their inherent inaccessibility, mountain regions are still fragile ecosystems threatened by human-related impacts such as animal agriculture, logging and erosion, acid deposition, and climate change.

For many wildlife species, these impacts are problematic. Wolverines, for example, depend on cold snow-pack to den and store food. As this resource becomes less permanent due to warming, wolverine populations may become physically and genetically isolated – leading to decline of the species.

Scientists and conservationists have long recognized the importance of mountains for both biodiversity and human well-being. To achieve effective and lasting protection of wildlife and resources such as water, mountains have to be pre-eminent in our thinking and implementation of conservation measures.

Mountain species are threatened by human-related impacts that cause isolation. As natural landscapes continue to become fragmented, habitat "islands" limit the ability of wildlife populations to move among ecosystems.

Climate change also has impacts on high elevation environments. In fact, impacts in mountain ecosystems may be greater than any other after those in the Arctic. Scientists have determined that it is important for conservationists to see climate change not as one of numerous independent variables acting on species survival in mountain landscapes, but as an exacerbating force over the many direct human alterations to these areas.

The distribution of biodiversity in mountain ecosystems is determined by such things as elevation and slope. These variables and the relative intactness of these ecosystems is likely to be a critical factor in maintaining the health of mountain species in the face of climate change.

Forests

9 Apr, 2018

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.

Urban Ecosystems

5 Apr, 2018

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.

Tropical Forests Overexploited By Logging

5 Apr, 2018

Widely hailed as a renewable natural resource, tropical timber from old-growth tropical forests is selectively logged worldwide at an unprecedented scale. But research now reveals that these sources of timber are far from sustainable and environmentally friendly.

Studies reveal that once prime tropical hardwoods – such as Brazilian cedars, ipe (Brazilian walnut), and rosewood – have been logged, they do not grow back to commercial levels and are at risk from disappearing altogether.

Slow growing and "commercially valuable" species of all kinds have been overexploited over the course of human history – just look at the whaling industry or fisheries. Yet many tropical timber species are still thought of as a renewable resource. We are only beginning to see over-exploitation parallels in tree species. Many high-value timber species are logged until their populations collapse altogether.

Timber harvests in Pará equate to almost half of all native forest roundlog production in Brazilian Amazonia – the largest old-growth tropical timber reserve controlled by any country. Brazil accounts for 85 percent of all native neotropical forest roundlog production. Researchers have found that loggers can no longer depend on areas where high-value species were formerly abundant to fetch high economic returns. This means that logging operations are continuously forced to extract timber trees from new areas of unlogged primary forests.

Even so-called ‘reduced-impact logging’ in tropical forests can rarely be defined as sustainable in terms of forest composition and dynamics in the aftermath of logging – never mind the greater susceptibility of logged forests to catastrophic fires. Environmental licensing and market certification of logging concessions need to take this into account, and review minimum preconditions in terms of volumetric quotas of roundlogs harvested per species and regeneration standards over multi-decade logging cycles.

After selective logging, there is no evidence that the composition of timber species and total forest value recovers beyond the first-cut. The most commercially-valuable timber species become predictably rare or economically extinct in old logging frontiers.

Only recent logging operations, which are furthest away from heavy-traffic roads, are the most selective, concentrating gross revenues on a few high-value species.

Managing yields of selectively-logged forests is crucial for the long-term integrity of forest biodiversity and financial viability of local industries.

Current commercial agreements could lead to ‘peak timber’ and then widespread economic extinctions across other tropical regions. We can already see a market shift, in which loggers in old depleted logging Amazonian frontiers are forced to depend on fast growing, soft-wood timber species.

Pandas In Peril

3 Apr, 2018

Like most endangered creatures, the giant panda has had to bear the brunt of man's frantic quest for development. No place embodies this phenomena more starkly than China, of which this furry animal is a native. The panda population in the plains of China have completely vanished over the millennia, and the only giant pandas remaining are those found in the Qinling Mountains of the Sichuan, Shaanxi and Gansu provinces of Central China. These rain-soaked forests are at elevations from 5,000 to 8,000 feet and are generally covered in clouds and mist.

An adult male panda can weigh over 350 lbs, the female 275 lbs, and measure from 2 to 3 feet in height up to its shoulders. With its huge round white-colored body, two black patches around the eyes, black ears and stout black legs, the panda looks very much like an over-bloated raccoon.

The breeding age of the pandas starts from about 4 to 8 years and remains reproductive up to the age of 20. The female gives birth between 95 to 150 days, and the panda cub is probably one of the most difficult creatures to raise. Almost blind, hairless and pink, the baby is 1/900th the size of its mother. The cubs remain without eyesight for a period of six to eight weeks and are just able to move around after three months.

Bird meat, rodents, carrion and grass form a part of the animal's diet, but these are secondary. Their primary diet is bamboo, which is available in plenty in the Qinling Mountains. The panda's huge round face is suggestive of a powerful set of jaws which itself is an adaption to a coarse diet such as the bamboo. The flowers of the bamboo have more nutrition than the stems. Re-flowering of the bamboos is a slow natural process and there is a fragile balance between it and the slow reproductive rate of the pandas – something that has evolved over a million years in these mountains.

Changes in climate threatens to upset this delicate balance. It presents a genuine threat to the habitat of the panda. A 3 to 4 degree rise in temperatures could easily wipe out half the bamboo forests and leave the panda starving. Scientists opine that owing to the serious damage to the ozone layer, a fallout of China's manic industrialization drive, temperatures could rise up to such a point that there would be none of these precious bamboo forests left after 50 to 100 years. While bamboo could be cultivated in other areas, it would have none of the nutritional value of the Qinling mountain bamboo. There's still plenty of bamboo being cultivated in China, but for the panda to move out of its habitat in search of its vital food will put it in direct confrontation with humans.

Poaching is another menace, and pandas have been captured over the years for exhibition in private zoos. Their pelts fetch a high price in the illegal wildlife trade. Giant pandas sometimes end up in traps laid for other animals and receive grievous injuries. The Chinese government has put in place strict penalties for panda poaching that entails a ten-year sentence and confiscation of property.

Authorities in the Shaanxi Province enacted a regional law in 2007 that marked the Qinling Mountains as a protected zone. The law also states that all development projects in the vicinity of the zone will be assessed for their impact on the ecology and bio-diversity of the region. The Natural Forest Protection Project, implemented by the Chinese Government, has gone a long way in securing a future for the pandas.

Despite these efforts, China has been criticized for showing little interest in true conservation. The Chinese government rents pandas to zoos around the world. Few pandas have been born in zoos, and only a handful of those have been released into the wild; the majority of which did not survive. The enormous amount of money spent on panda breeding programs has been criticized, as the money could be used much more effectively by saving wild habitats.

Zoo pandas suffer the same stresses all wild animals face in captivity. They are moved from zoo to zoo, usually more for political and economic reasons rather than genetic management. Their natural habitat can never be truly simulated, leading to changes in behavior, prolonged inactivity, health problems, stereotypical behavior and lower levels of immunity creating higher susceptibility to illness and disease.

Animal advocates argue that the pandas' welfare should be put above propaganda and profits; pandas should be put in refuges out of the public eye to eliminate the stress they endure due to such exposure.

Wildlife organizations have had an impact by establishing panda natural reserves and conservation programs. Integrating reserves with forest farms and bamboo corridors enable pandas to forage for more food and come into contact with new breeding mates.

A 17 percent rise in the panda population has been witnessed in the past decade. From a count of 1,596 individuals in 2003, it has risen to 1,864. Of these, though, 50 pandas are condemned to captivity in 18 zoos spanning 13 countries.

Dealing With Woodchucks

3 Apr, 2018

Woodchucks are harmless, comical vegetarians who are commonly sighted in suburban backyards and along roadways. Conflicts usually arise over who gets to eat the garden vegetables. Suburban landscapes provide perfect habitat for woodchucks. Our raised decks provide cover and a perfect place to raise young, and our lush lawns provide a virtual buffet. Most woodchuck conflicts occur in spring and summer, just when birthing season has begun. That's why problems need to be solved in a way that doesn't leave orphaned young behind.

KEEPING WOODCHUCKS OUT OF GARDENS

The best way to exclude woodchucks is by putting up a simple chicken wire or mesh fence. All you need is a roll of 4-foot high chicken wire and some wooden stakes. Once the job is done, it won't matter how many woodchucks are in the neighborhood because they won't be getting into your garden.

There are 2 secrets for making a successful fence:

Tip #1: The top portion of the fence only needs to be 2 ½ to 3 feet high but it should be staked so that it's wobbly -- i.e. the mesh should not be pulled tight between the stakes but rather, there should be some "give" so that when the woodchuck tries to climb the fence, it will wobble which will discourage him. Then he'll try to dig under the fence, so:

Tip #2: Extend your mesh fence 4 inches straight down into the ground and then bend it and extend the final 8-12 inches outward, away from the garden, in a "L"-shape which creates a false bottom (you can also put this mesh "flap" on top of the ground but be sure to secure it firmly with landscaping staples or the woodchuck will go under it). When the woodchuck digs down and hits this mesh flap, he'll think he can't dig any farther and give up. It won't occur to him to stand back a foot and THEN start digging!

IF YOU AREN'T WILLING TO PUT UP A FENCE, you can also try the following scare techniques, which do work in some cases:

1) Line your garden with helium-filled, silver mylar balloons or make a low fence of twisted, reflective mylar tape bought at your local party store. Be sure to purchase heavier weights to attach to the bottom of the balloons. The balloons bobbing in the wind will scare the woodchucks.

2) Sprinkle cayenne pepper around the plants and spray your plants with a taste repellent such as Ropel (available at garden stores) every 2 weeks.

GETTING WOODCHUCKS OUT FROM UNDER SHEDS

Woodchucks don't undermine foundations and really aren't likely to damage your shed. In spring and summer, the woodchuck under your shed is probably a mother nursing her young, which is why you should consider leaving them alone. Be sure you really need to evict the woodchuck before taking action. If you must, put some dirty kitty litter down the woodchuck burrow -- the urinated part acts as a predator odor, which often causes the entire family to leave. Ammonia-sprinkled rags or sweaty, smelling socks placed in the burrow may also cause self-eviction.

WOODCHUCKS & CHILDREN

Woodchucks are harmless vegetarians who flee when scared. Remember that even a small child looks like a giant predator to the woodchuck. There is no cause for alarm. Woodchucks live under houses and day care centers all over the country. Healthy woodchucks simply don't attack children or pets. If chased, woodchucks will quickly flee to their burrows.

WOODCHUCKS & RABIES

Woodchucks have a higher susceptibility to rabies than other rodents, yet the incidence of rabies in woodchucks is still very low. Woodchucks are much more susceptible to the roundworm brain parasite, which causes symptoms that look exactly like rabies. Roundworm is NOT airborne -- it can only be transmitted through the oral-fecal route, i.e. the ingestion of an infected animal's feces.

SETTING A TRAP FOR WOODCHUCKS & CATCHING A SKUNK

This is a common occurrence when traps are left open at night. You can let the skunk out without getting sprayed just by knowing that skunks have terrible eyesight and only spray when something comes at them fast, like a dog. If you move slowly and talk soothingly, you shouldn't get sprayed. Skunks stamp their front feet as a warning when they're nervous, so if the skunk stamps, just remain motionless for a minute until he stops stamping, then proceed. You can drape a towel -- slowly-- over the trap prior to opening it. Once the trap door is opened, the skunk will beeline for home. If you must trap and relocate a woodchuck, remember to close the trap at night so another skunk doesn't get caught.

TRAPPING WOODCHUCKS

Trapping won't solve the problem. As long as woodchuck habitat is available, there will be woodchucks. Even in studies where all the woodchucks are trapped out of an area, others from the surrounding area quickly move into the vacated niche. In addition, trapping and relocating woodchucks may lead to starving young being left behind. Homeowners are then horrified to smell a foul odor. It's much more effective to simply exclude woodchucks from areas where they're not wanted. Don't trap unless an animal is stuck somewhere and can't get out, or poses an immediate threat to humans or domestic animals.

Why Forests Matter

3 Apr, 2018

Many factors affect forests include logging, urban sprawl, human-caused forest fires, acid rain, invasive species, and the slash and burn practices of swidden agriculture or shifting cultivation. The loss and re-growth of forest leads to a distinction between two broad types of forest, primary or old-growth forest and secondary forest.

There are also many natural factors that can cause changes in forests over time including forest fires, insects, diseases, weather, competition between species, etc. The World Resources Institute recorded that only 20% of the world's original forests remained in large, intact tracts of undisturbed forest. More than 75% of these intact forests lie in three countries - the boreal forests of Russia and Canada and the rainforest of Brazil.

Old-growth forests contain mainly natural patterns of biodiversity in established seral patterns, and they contain mainly species native to the region and habitat. The natural formations and processes have not been affected by humans with a frequency or intensity to change the natural structure and components of the habitat. Secondary forest contains significant elements of species which were originally from other regions or habitats.

Smaller areas of woodland in cities may be managed as Urban forestry, sometimes within public parks. These are often created for human benefits.

Rainforests

Rainforests are forests characterized by high rainfall, with definitions based on a minimum normal annual rainfall of 68 to 78 inches. The monsoon trough, alternatively known as the intertropical convergence zone, plays a significant role in creating the climatic conditions necessary for the earth's tropical rainforests.

Rainforests cover 2% of the earth's surface, or 6% of its land mass. They originally covered at least twice that area. Tropical rainforests are the earth's oldest living ecosystems. Fossil records show that the forests of Southeast Asia have existed in more or less their present form for 70 to 100 million years.

Around 40% to 75% of all biotic species are indigenous to the rainforests. It has been estimated that there may be many millions of species of plants, insects and microorganisms still undiscovered in tropical rainforests.

Tropical rainforests have been called the "jewels of the earth" and the "world's largest pharmacy", because over one quarter of natural medicines have been discovered there. Rainforests are also responsible for 28% of the world's oxygen turnover, processing it through photosynthesis from carbon dioxide and storing it as carbon through biosequestration.

The undergrowth in a rainforest is restricted in many areas by the poor penetration of sunlight to ground level. This makes it easy to walk through undisturbed, mature rainforest. If the leaf canopy is destroyed or thinned, the ground beneath is soon colonized by a dense, tangled growth of vines, shrubs and small trees, called a jungle.

There are two types of rainforest, tropical rainforest and temperate rainforest.

Tropical rainforests are rainforests in the tropics, found in the equatorial zone (between the Tropic of Cancer and Tropic of Capricorn). Tropical rainforests are present in Southeast Asia (from Myanmar (Burma) to Philippines, Indonesia, Papua New Guinea and northeastern Australia), Sri Lanka, sub-Saharan Africa from Cameroon to the Congo (Congo Rainforest), South America (e.g. the Amazon Rainforest), Central America (e.g. Bosawás, southern Yucatán Peninsula-El Peten-Belize-Calakmul), and on many of the Pacific Islands (such as Hawai).

Temperate rainforests are rainforests in temperate regions. They occur in North America (in the Pacific Northwest, the British Columbia Coast and in the inland rainforest of the Rocky Mountain Trench east of Prince George), in Europe (parts of the British Isles such as the coastal areas of Ireland and Scotland, southern Norway, parts of the western Balkans along the Adriatic coast, as well as in the North West of Spain and coastal areas of the eastern Black Sea, including Georgia and coastal Turkey), in East Asia (in southern China, Taiwan, much of Japan and Korea, and on Sakhalin Island and the adjacent Russian Far East coast), in South America (southern Chile) and also in Australia and New Zealand.

More than half of the world's species of plants and animals are found in the rainforest. Rainforests support a very broad array of fauna, including mammals, reptiles, birds and invertebrates. Mammals may include primates, felids and other families. Reptiles include snakes, turtles, chameleons and other families; while birds include such families as vangidae and Cuculidae. Dozens of families of invertebrates are found in rainforests. Fungi are also very common in rainforest areas as they can feed on the decomposing remains of plants and animals. Many rainforest species are rapidly disappearing due to deforestation, habitat loss and pollution of the atmosphere.

On January 18, 2007, FUNAI reported also that it had confirmed the presence of 67 different uncontacted tribes in Brazil. The province of Irian Jaya or West Papua in the island of New Guinea is home to an estimated 44 uncontacted tribal groups. The tribes are in danger because of the deforestation, especially in Brazil. Central African rainforest is home of the Mbuti pygmies, one of the hunter-gatherer peoples living in equatorial rainforests characterized by their short height (below 59 inches, on average).

Tropical and temperate rainforests have been subjected to heavy logging and agricultural clearance throughout the 20th century and the area covered by rainforests around the world is shrinking. Biologists have estimated that large numbers of species are being driven to extinction, possibly more than 50,000 a year. A quarter or more of all species on earth could be exterminated within 50 years due to the removal of habitat with destruction of the rainforests. Four-fifths of the nutrients in the rainforests are in the vegetation. This means that the soils are nutrient-poor and become eroded and unproductive within a few years after the rainforest is cleared.

Another factor causing the loss of rainforest is expanding urban areas. Littoral rainforest growing along coastal areas of eastern Australia is now rare due to ribbon development to accommodate the demand for seachange lifestyles.

The forests are being destroyed at a rapid pace. Almost 90% of West Africa's rainforest has been destroyed. Since the arrival of humans 2000 years ago, Madagascar has lost two thirds of its original rainforest. At present rates, tropical rainforests in Indonesia will be logged out in 10 years and Papua New Guinea in 13 to 16 years. All the primary rainforests in India, Bangladesh, Sri Lanka and Haiti have been destroyed already. The Ivory Coast rainforests have been almost completely logged. The Philippines lost 55% of its forest between 1960 and 1985; Thailand lost 45% of its forest between 1961 and 1985.

Rainforests support 90,000 of the 250,000 identified plant species. Scientists estimate that there are at least 30,000 as yet undiscovered plants, most of which are rainforest species. A typical four square mile patch of rainforest contains as many as 1,500 species of flowering plants, 750 species of trees, 125 mammal species, 400 species of birds, 100 of reptiles, 60 of amphibians, and 150 different species of butterflies. In one study, one square meter of leaf litter, when analyzed, turned up 50 species of ants alone.

Many of the foods we eat today originated in rainforests: avocado, banana, black pepper, Brazilian nuts, cayenne pepper, cassava/manioc, cashews, chocolate/ cocoa, cinnamon, cloves, coconut, coffee, cola, corn/maize, eggplant, fig, ginger, guava, herbal tea ingredients (hibiscus flowers, orange flowers and peel, lemon grass), jalapeño, lemon, orange, papaya, paprika, peanut, pineapple, rice, winter squash, sweet pepper, sugar, tomato, turmeric, vanilla, and Mexican yam. The wild strains still in the rainforests of many of these plants provide genetic materials essential to fortify our existing agricultural stock. Many other rainforest plants have great promise to become other staple foods.

The uneven distribution of wealth and land is one major factor in the destruction of tropical forests. The World Bank estimates that of the 2.5 billion people now living in the tropics one billion exist in absolute poverty.

Desert Features

30 Mar, 2018

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.

Interacting With Marine Mammals

30 Mar, 2018

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.

What Is A Dead Zone?

28 Mar, 2018

"Dead zone" is a more common term for hypoxia, which refers to a reduced level of oxygen in the water. Hypoxic zones are areas in the ocean of such low oxygen concentration that animal life suffocates and dies, and as a result are sometimes called "dead zones."

One of the largest dead zones forms in the Gulf of Mexico every spring. Each spring as farmers fertilize their lands preparing for crop season, rain washes fertilizer off the land and into streams and rivers.

Less oxygen dissolved in the water is often referred to as a “dead zone” because most marine life either dies, or, if they are mobile such as fish, leave the area. Habitats that would normally be teeming with life become, essentially, biological deserts.

Hypoxic zones can occur naturally, but scientists are concerned about the areas created or enhanced by human activity. There are many physical, chemical, and biological factors that combine to create dead zones, but nutrient pollution is the primary cause of those zones created by humans.

Excess nutrients that run off land or are piped as wastewater into rivers and coasts can stimulate an overgrowth of algae, which then sinks and decomposes in the water. The decomposition process consumes oxygen and depletes the supply available to healthy marine life.

Dead zones occur in many areas, particularly along the East Coast, the Gulf of Mexico, and the Great Lakes, but there is no part of the world that is immune. The second largest dead zone in the world is located in the U.S., in the northern Gulf of Mexico.

Dealing With Raccoons

28 Mar, 2018

Raccoons are intelligent, fascinating and highly adaptable mammals. As we destroy more and more wildlife habitat, we force animals like raccoons to come into closer contact with us. There's no need to panic or pay hundreds of dollars for trapping services because most problems can be easily resolved with some simple advice and household materials. Many conflicts occur in spring and summer when raccoons take advantage of cavities in human dwellings to raise their young. This is why it's vital to solve problems in a way that doesn't separate a mother from her cubs. Here are some solutions to common raccoon problems:

KEEPING RACCOONS OUT OF GARBAGE

Overflowing or uncovered garbage cans provide an open invitation to hungry raccoons. The simplest solution is to put out your garbage cans for pick-up in the morning, after the nocturnal raccoons have returned to their dens. If you must put out your garbage cans at night, get the kind of plastic garbage can with a tall (4' high) TWIST-ON lid which raccoons can't open. Another option is to build a simple wooden box outside for storing garbage cans. For easy access, the top should be hinged and have a latch in front secured with a snap hook.

RACCOONS IN DUMPSTERS

Often garbage disposal companies don't close dumpster lids after emptying them in the early morning hours. Raccoons are enticed by the food smells, jump in, and can't climb the slippery sides. This problem is easily resolved by putting some strong branches or plank-like pieces of wood in the dumpster so the raccoons can climb out. If your company leaves dumpster lids open all the time, post a sign telling employees that it's vital to keep the lid closed so animals don't become trapped inside.

DO DAYTIME RACCOONS HAVE RABIES?

Even though raccoons are considered nocturnal, mother raccoons sometimes nap in trees or forage during the day when they have nursing cubs which depletes their energy. Coastal raccoons take advantage of the tides and are often seen by day. Call your local animal control officer or police if an adult raccoon seen in daytime is acting at all sick or showing abnormal behaviors such as partial paralysis, circling, staggering as if drunk or disoriented, self-mutilating, screeching, or exhibiting unprovoked aggression or unnatural tameness. Otherwise, just leave the raccoon alone and keep people and companion animals away from the animal.

GETTING RACCOONS OUT OF ATTICS & CHIMNEYS

In spring and summer, mother raccoons often take advantage of chimneys and attics as denning sites for raising cubs. The easiest and best solution is to wait a few weeks for the raccoons to move out on their own. As soon as the cubs are old enough to go on nighttime outings with their mother, she will take them out of the chimney once and for all rather than continually carrying them back and forth. Mother raccoons clean their babies meticulously to avoid attracting predators. If you absolutely must evict the raccoon family, remember that raccoons look for quiet, dark and non-noxious smelling places to raise their young. By creating the opposite conditions, you can evict them using the following methods:

Eviction of Chimney Raccoons: Keep the damper closed and put a blaring radio (rock or rap music works best) in the fireplace. Then put a bowl of ammonia on a footstool near the damper. Apply these deterrents JUST BEFORE DUSK; mother raccoons won't want to move their cubs in broad daylight. Be patient, it may take a few days for the mother to move her young. Once you inspect and make sure all the raccoons are gone, promptly call a chimney sweep to install a mesh chimney cap (the best kind has a stainless steel top) and this situation will not recur.

Eviction of Attic Raccoons: Leave all the lights on and place a blaring radio and rags sprinkled with 1/4 cup of ammonia around the attic. You can also enhance the deterrent effect by adding cayenne pepper or the commercial repellent Repel around the attic and also hanging an electrician's drop light over the denning area. Apply these deterrents JUST BEFORE DUSK; mother raccoons will not want to move their cubs in daylight. Be patient, it may take a few days for the mother to move her young. Once the raccoons are gone, promptly seal any entry hole and this situation will not recur.

RACCOONS EATING CAT FOOD

If you leave food outside all the time, you will attract raccoons and other animals. The solution is to feed the cats only at a certain time in the morning or midday, then take away any uneaten food. The cats will get used to the schedule and modify their behavior accordingly.

RACCOONS COMING THROUGH CAT DOORS

No self-respecting raccoon is going to ignore a free buffet! The best solution is to feed your cats indoors and not use a cat door at all. There are strong, electrically controlled doors that you can purchase which only let your designated animals in.

RACCOONS & POND FISH

It is difficult to have a delicacy like fish in an area and expect raccoons not to take notice! The best solution is to maintain a higher water level (at least 3 feet deep) and stack cinder blocks, large rocks, or ceramic pipes in the bottom of the pond so the fish can escape from the raccoons and take refuge.

RACCOONS DESTROYING LAWNS

The raccoons are going after the grubs in your lawn. If you keep your lawn well watered, this exacerbates the problem since it drives the grubs to the surface layer of the soil. The good news is that the grubbing activity, although unsightly, does not permanently damage the lawn. A long-term, ecological solution is to apply the product "Milky Spore" to the soil. This natural bacteria will spread and get rid of the grubs, but it takes a long time to work (1+ years). Don't use chemical pesticides due to their toxic effect on the environment, people and animals.

RACCOONS IN THE CHICKEN COOP

The only answer is to reinforce your chicken coop so the raccoons cannot have access to the chickens. Heavy gage welded wire should be used and another layer of finer mesh put over it to prevent raccoons from being able to reach through. Although an inconvenience, once an animal pen is well reinforced and maintained, there will be no more problems.

TRAPPING RACCOONS

Trapping is rarely a solution to wildlife nuisance problems. As one animal is removed, another from the surrounding area will soon take his place. The answer is to exclude the animal from the food or nesting source that is attracting him.

Nuisance wildlife control companies charge a fee -- sometimes hundreds of dollars -- for problems that homeowners can often resolve themselves. In addition, when animals are trapped during birthing season, starving babies may be left behind. Homeowners are then horrified to find a foul odor emanating throughout their house. Animals should never be trapped under extreme conditions, such as on sunny rooftops, in rain, snow, sleet, or other bad weather which will cause the animals to suffer and die.

Don't trap unless an animal is stuck somewhere and can't get out or poses an immediate threat to humans or domestic animals. If you do hire a nuisance trapper, ensure that humane practices are followed and no animals are orphaned in the process.

MAKING SURE RACCOONS ARE GONE

Most attics contain clutter, making it hard to verify if the raccoons are gone. Before sealing any entry hole, stuff it first with newspaper and see if the paper stays in place for 3 successive nights. If so, the den is vacated. After sealing the entry hole with hardware cloth, make sure no raccoons are left behind by leaving a sardine or marshmallows in the attic and check if the food is uneaten after 24 hours, or sprinkle flour in front of the entry hole and check for footprints of a raccoon trying to get out.

Types of Deserts

25 Mar, 2018

Deserts are classified by their geographical location and dominant weather pattern as trade wind, midlatitude, rain shadow, coastal, monsoon, or polar deserts. Former desert areas presently in nonarid environments are paleodeserts, and extraterrestrial deserts exist on other planets.

Trade Wind Deserts

The trade winds in two belts on the equatorial sides of the Horse Latitudes heat up as they move toward the Equator. These dry winds dissipate cloud cover, allowing more sunlight to heat the land. Most of the major deserts of the world lie in areas crossed by the trade winds. The world's largest desert, the Sahara of North Africa, which has experienced temperatures as high as 57° G, is a trade wind desert.

Midlatitude Deserts

Midlatitude deserts occur between 30° and 50° N. and S., poleward of the subtropical highpressure zones. These deserts are in interior drainage basins far from oceans and have a wide range of annual temperatures. The Sohoran Desert of southwestern North America- is a typical midlatitude desert.

Rain Shadow Deserts

Rain shadow deserts are formed because tall mountain ranges prevent moisture-rich clouds from reaching areas on the lee, or protected side, of the range. As air rises over the mountain, water is precipitated and the air loses its moisture content. A desert is formed in the leeside "shadow" of the range.

Coastal Deserts

Coastal deserts generally are found on the western edges of continents near the Tropics of Cancer and Capricorn. They are affected by cold ocean currents that parallel the coast. Because local wind systems dominate the trade winds, these deserts are less stable than other deserts. Winter fogs, produced by upwelling cold currents, frequently blanket coastal deserts and block solar radiation. Coastal deserts are relatively complex because they are at the juncture of terrestrial, oceanic, and atmospheric systems. A coastal desert, the Atacama of South America, is the Earth's driest desert. In the Atacama, measurable rainfall 1 millimeter or more of rain may occur as infrequently as once every 5-20 years. Crescent-shaped dunes are common in coastal deserts such as the Namib, Africa, with prevailing onshore winds.

Monsoon Deserts

"Monsoon," derived from an Arabic word for "season," refers to a wind system with pronounced seasonal reversal. Monsoons develop in response to temperature variations between continents and oceans. The southeast trade winds of the Indian Ocean, for example, provide heavy summer rains in India as they move onshore. As the monsoon crosses India, it loses moisture on the eastern slopes of the Aravalli Range. The Rajasthan Desert of India and the Thar Desert of Pakistan are parts of a monsoon desert region west of the range.

Polar Deserts

Polar deserts are areas with annual precipitation less than 250 millimeters and a mean temperature during the warmest month of less than 10° C. Polar deserts on the Earth cover nearly 5 million square kilometers and are mostly bedrock or gravel plains. Sand dunes are not prominent features in these deserts, but snow dunes occur commonly in areas where precipitation is locally more abundant. Temperature changes in polar deserts frequently cross the freezing point of water. This "freezethaw" alternation forms patterned textures on the ground, as much as 5 meters in diameter.

Grassland Ducks In Trouble

25 Mar, 2018

The prairie grasslands ecoregion is often referred to as a “duck factory” because it produces roughly 50% of America’s ducks even though it occupies only about 10% of total duck breeding territory. Duck species such as northern pintails and mallards form mating pairs and breed in the scattered wetlands of this region.

Ducks seem to prefer the smaller wetlands because the isolated ponds allow each pair to have its own space. In fact, ducks already inhabiting a small pond may chase away other ducks in order to protect their territory.

Mallards, pintails, and blue-winged teals are all dabbling ducks, which means they feed in the shallow wetland waters by dipping their heads just below the water surface to eat plants, insects, and small fish. Diving ducks, like the redhead, dive into the deep water to feed on the bottom of the pond.

Ducks often prefer to nest near the wetlands and ponds of the prairie grasslands region in order to feed on the plentiful resources available there. They also prefer this area because the tall grass habitat provides protection from predators.

Agriculture and other activities have decreased the total amount of grassland in the prairie grasslands region, and scientists have found that as the grassland diminishes and the habitat becomes fragmented, predators destroy more duck nests. Part of the reason for this increase in predation is that predators such as foxes and crows are better able to see nests in less grassy and more fragmented areas.

The number of ducks that breed successfully in the prairie grasslands region depends on the wetland conditions that year. In the past, lower duck populations have resulted from unusually dry years with fewer wetland areas.

Wetlands in the prairie grassland region are likely to be affected by forecasted changes in climate, but the magnitude of the impact is uncertain. Scientists initiated a study to examine how prairie grassland wetlands might respond to climate change. Model simulations determined that a warmer climate of only a few degrees Celsius increased the frequency and duration of droughts, and produced less favorable vegetation conditions in semi-permanent wetlands for most of the region. Climate scenarios using smaller temperature and rainfall changes resulted in geographic shifts in the locations of prairie grassland wetlands. During the model simulations, the scientists found that if rainfall increased with temperature, the location of the most productive wetlands would remain approximately the same. However, if precipitation remained stable or decreased, models predicted that most of the prairie grassland region would become too dry to maintain the wetland conditions.

These findings indicate that the duck factory is vulnerable to climate change, particularly under conditions of water stress.