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A Food Pyramid in the Hot Desert Biome      Here we see a food pyramid that shows how the Kilocalories pass up the food chain.      The first trophic level is occupied by the primary producers, which are the plants.  Plants make food through photosynthesis. The limiting factor for these plants is the shortage of water, so they produce fewer than 200 Kilocalories of food for the animals for each square meter each year.     The primary consumers, who eat the plants, occupy the second trophic level. These animals have very little to eat, and are small. Many are insects, or reptiles, who are cold blooded and who use less energy to maintain their bodies than mammals and birds do. As food for predators, they provide about 20 Kilocalories per square meter per year for predators.      The predators are the secondary consumers. They occupy the third trophic level. Again we see cold-blooded animals, such as snakes, insect-eating lizards, and tarantualas. Only about 2 Kilocalories per square meter per year are stored in their bodies. In the harsher desert environments, they are the top predators.     In areas where deserts get more rain, more plant material is produced and a few tertiary consumers may be able to survive. They form a fourth trophic level.      This diagram shows the energy available at each trophic level in the hot desert biome. These numbers tell about the numbers of Kilocalories per square meter per year.  Cold Desert Energy Pyramid  Introduction to Desert Biomes  Return to Introduction to Biomes © Elizabeth Anne Viau, 1999. This material may be used freely for instructional purposes but not sold for a price beyond the cost of reproduction. Please inform the author if you use it at eviau@earthlink.net

Many species of animal life can be found in the rain forest. Common characteristics found among mammals and birds (and reptiles and amphibians, too) include adaptations to a life in the trees, such as the prehensile tails of New World monkeys. Other characteristics are bright colors and sharp patterns, loud vocalizations, and diets heavy on fruits. Insects make up the largest single group of animals that live in tropical forests. They include brightly colored butterflies, mosquitoes, camouflaged stick insects, and huge colonies of ants. The Amazon river basin rainforest contains a wider variety of plant and animal life than any other biome in the world. The second largest population of plant and animal life can be found in scattered locations and islands of Southeast Asia. The lowest variety can be found in Africa. There may be 40 to 100 different species in 2.5 acres ( 1 hectare) of a tropical rain forest.   When early explorers first discovered the rainforests of Africa, Southeast Asia and South America, they They were amazed by the dense growth, trees with giant buttresses, vines and epiphytes . The tropical vegetation grew so dense that it was difficult to cut one's way through it. It was thought at the time that the soil of a rainforest must be very fertile, filled with nutrients, enabling it to support the immense trees and other vegetation they found. Today we know that the soil of the tropical rainforests is shallow, very poor in nutrients and almost without soluble minerals. Thousands of years of heavy rains have washed away the nutrients in the soil obtained from weathered rocks. The rainforest has a very short nutrient cycle. Nutrients generally stay in an ecosystem by being recycled and in a rainforest are mainly found in the living plants and the layers of decomposing leaf litter. Various species of decomposers like insects, bacteria, and fungi make quick work of turning dead plant and animal matter into nutrients. Plants take up these nutrients the moment they are released. A study in the Amazon rainforest found that 99% of nutrients are held in root mats. When a rainforest is burned or cut down the nutrients are removed from the ecosystem. The soil can only be used for a very short time before it becomes completely depleted of all nutrients.

Besides these four layers, a shrub/sapling layer receives about 3 % of the light that filters in through the canopies. These stunted trees are capable of a sudden growth surge when a gap in the canopy opens above them. The air beneath the lower canopy is almost always humid. The trees themselves give off water through the pores (stomata) of their leaves. This process, called transpiration, can account for as much as half of the precipitation in the rain forest. Rainforest plants have made many adaptations to their environment. With over 80 inches of rain per year, plants have made adaptations that helps them shed water off their leaves quickly so the branches don't get weighed down and break. Many plants have drip tips and grooved leaves, and some leaves have oily coatings to shed water. To absorb as much sunlight as possible on the dark understory, leaves are very large. Some trees have leaf stalks that turn with the movement of the sun so they always absorb the maximum amount of light. Leaves in the upper canopy are dark green, small and leathery to reduce water loss in the strong sunlight. Some trees will grow large leaves at the lower canopy level and small leaves in the upper canopy. Other plants grow in the upper canopy on larger trees to get sunlight. These are the epiphytes such as orchids and bromeliads. Many trees have buttress and stilt roots for extra support in the shallow, wet soil of the rainforests. Over 2,500 species of vines grow in the rainforest. Lianas start off as small shrubs that grow on the forest floor. To reach the sunlight in the upper canopy it sends out tendrils to grab sapling trees. The liana and the tree grow towards the canopy together. The vines grow from one tree to another and make up 40% of the canopy leaves. The rattan vine has spikes on the underside of its leaves that point backwards to grab onto sapling trees. Other "strangler" vines will use trees as support and grow thicker and thicker as they reach the canopy, strangling its host tree. They look like trees whose centers have been hollowed out. Dominant species do not exist in tropical rainforests. Lowland dipterocarp forest can consist of many different species of Dipterocarpaceae, but not all of the same species. Trees of the same species are very seldom found growing close together. This bio diversity and separation of the species prevents mass contamination and die-off from disease or insect infestation. Bio diversity also insures that there will be enough pollinators to take care of each species' needs. Animals depend on the staggered blooming and fruiting of rainforest plants to supply them with a year-round source of food.

There are four very distinct layers of trees in a tropical rain forest. These layers have been identified as the emergent, upper canopy, understory, and forest floor. Emergent trees are spaced wide apart, and are 100 to 240 feet tall with umbrella-shaped canopies that grow above the forest. Because emergent trees are exposed to drying winds, they tend to have small, pointed leaves. Some species lose their leaves during the brief dry season in monsoon rainforests. These giant trees have straight, smooth trunks with few branches. Their root system is very shallow, and to support their size they grow buttresses that can spread out to a distance of 30 feet. The upper canopy of 60 to 130 foot trees allows light to be easily available at the top of this layer, but greatly reduced any light below it. Most of the rainforest's animals live in the upper canopy. There is so much food available at this level that some animals never go down to the forest floor. The leaves have "drip spouts" that allows rain to run off. This keeps them dry and prevents mold and mildew from forming in the humid environment. The understory, or lower canopy, consists of 60 foot trees. This layer is made up of the trunks of canopy trees, shrubs, plants and small trees. There is little air movement. As a result the humidity is constantly high. This level is in constant shade. The forest floor is usually completely shaded, except where a canopy tree has fallen and created an opening. Most areas of the forest floor receive so little light that few bushes or herbs can grow there. As a result, a person can easily walk through most parts of a tropical rain forest. Less than 1 % of the light that strikes the top of the forest penetrates to the forest floor. The top soil is very thin and of poor quality. A lot of litter falls to the ground where it is quickly broken down by decomposers like termites, earthworms and fungi. The heat and humidity further help to break down the litter. This organic matter is then just as quickly absorbed by the trees' shallow roots

It is estimated that nearly half of the world's estimated 10 million species of plants, animals, and microorganisms will be destroyed or severely threatened over the next quarter-century due to rainforest deforestation.

Commercial logging is the single largest cause of rainforest destruction, both directly and indirectly. Other activities destroying the rainforest, including clearing land for grazing animals and subsistence farming. The simple fact is that people are destroying the Amazon rainforest and the rest of the rainforests of the world because "they can't see the forest for the trees."

When a medicine man dies without passing his arts on to the next generation, the tribe and the world loses thousands of years of irreplaceable knowledge about medicinal plants.

Animals of the rain forests are provided with a variety of habitats in the different layers of the forest trees. Some live at the top of the tallest trees while others live in the lower zones. Some animals, live on the ground level or even below the surface and so we have this vast and complex pattern of plant and animal life which has been evolving steadily for millions of years.

Animals of the rain forests are provided with a variety of habitats in the different layers of the forest trees. Some live at the top of the tallest trees while others live in the lower zones. Some animals, live on the ground level or even below the surface and so we have this vast and complex pattern of plant and animal life which has been evolving steadily for millions of years.

tropical rainforests are considered a type of tropical wet forest (or tropical moist broadleaf forest) and may also be referred to as lowland equatorial evergreen rainforest

and may also be referred to as lowland equatorial evergreen rainforest

Rainforests are home to half of all the living animal and plant species on the planet.[2] Tropical rain forests are called the "world's largest pharmacy" because over one-quarter of modern medicines originate from its plants.

Presently there are 38 known species of mammals that are extinct.

There are over 1,000 animal species that are endangered at varied levels, across the world.

Which Way Our Future Aboriginal people are very proud of their indigenous heritage. They want the importance of their culture recognised, respected and protected. To ensure the ongoing survival of their culture, Rainforest Aboriginal people have been negotiating for shared management of their traditional country with government agencies. Rainforest Aboriginal people want to be to be recognised as the traditional land owners of the World Heritage Area with distinct cultures and individual needs. They would like to negotiate plans for their traditional lands and be involved with all aspects of land management decision making, and activities such as tourism and walking tracks planning, fire management, wildlife protection, and on the ground management. Other important goals include ranger training and employment opportunities so that Rainforest Aboriginal people can actively use their customary and contemporary land management knowledge to continue their traditions of managing their country.

The identification, ongoing protection and presentatiosn of cultural values is paramount. This includes cultural sites and their traditional knowledge (sometimes referred to as intellectual and cultural property rights) such as food and medicine resources. They want to be able to hunt and gather their traditional foods and other resources, while managing impacts which have the potential to impair these activities through disturbance and habitat destruction. Other important aspirations relate to the future of Rainforest Aboriginal people's communities and their survival into the 21st century. Many Rainforest Aboriginal people want to get more involved in cultural tourism because it means they can present their culture and benefit economically. One of the most heart-felt aspirations Rainforest Aboriginal people have is to get secure title to their traditional lands to ensure the integrity and survival of their cultures.  

Sahara Desert Plants The Sahara Desert is often described as a bleak and barren plain. In truth, it is very beautiful and full of different Sahara Desert plants. Sahara Desert Plants Among desert areas throughout the Earth, there are two types. The cold type of desert, which is often found in Arctic regions, is an area that gets very little precipitation. The cold desert can be covered in snow, however, and the temperatures here are chilly and unsuitable for sustaining many life forms. The other type of desert is known as the hot desert, and this is what people usually think of when they picture a desert area. This type of desert is extremely warm and dry, with temperatures reaching unbearable levels, and little to no rain to sustain those who live here. The biggest of the hot deserts is the Sahara Desert, located in Africa. Although this desert is not the most hospitable place for organisms to take up residence, the Sahara Desert plants defy the odds and thrive here.

The billions of leaves of the canopy, acting as miniature solar panels, provide the source of power for the forest by converting sunlight to energy through photosynthesis. Photosynthesis is the process by which plants convert atmospheric carbon dioxide and water into oxygen and simple sugars. Since the rate of photosynthesis of canopy trees is so high, these plants have a higher yield of fruits, seeds, flowers, and leaves which attract and support a wide diversity of animal life. Besides attracting a broad array of wildlife, the canopy plays an important role in regulating regional and global climate because it is the principal site of the interchange of heat, water vapor, and atmospheric gases. In addition to collecting solar energy and regulating the climate, the canopy shields the understory from harsh and intense sunlight, drying winds, and heavy rainfall, and retains the moisture of the forest below. Thus the forest interior is a far less volatile environment than the upper parts of the canopy ceiling. The interior region is protected from the extremes of the canopy: temperature fluctuations, damaging solar radiation, and strong winds. Light levels are diffuse and subdued, the humidity is higher and more constant, and there is very little direct sunlight in the lower canopy.

The overstory is characterized by scattered emergent trees that tower above the rest of the canopy, the tops of some species exceeding 210 feet (65 m). Below the overstory trees, the canopy stretches for vast distances, seemingly unbroken when observed from an airplane. However, despite overlapping tree branches, canopy trees rarely interlock or even touch. Instead they are separated from one another by a few feet. Why the branches of these trees do not touch is still a mystery, but it is thought that it might serve as protection from infestations from tree-eating caterpillars and tree diseases like leaf blight. To survive, canopy dwellers must have the ability to negotiate these gaps by climbing, leaping, gliding, or flying.

Afghanistan's 1964 constitution provided for free and compulsory education at all levels, but this changed when the Taliban gained control in 1996.