Deserts cover about one fifth of the Earth's surface and occur where rainfall is less than 50 cm/year. The four major North American deserts of this type are the Chihuahuan, Sonoran, Mojave and Great Basin.
Rainfall is usually very low and/or concentrated in short bursts between long rainless periods. Evaporation rates regularly exceed rainfall rates. Sometimes rain starts falling and evaporates before reaching the ground.
Soils are shallow, rocky or gravely with good drainage and have no subsurface water. They are coarse because there is less chemical weathering (acid rain) (Ager, 128-140).
The finer dust and sand particles are blown elsewhere, leaving heavier pieces behind. Some plants found in extreme deserts include: yuccas, ocotillo, turpentine bush, prickly pears, false mesquite, agaves and brittlebush. Some animals that you may find include small (active at night) carnivores (Anayev, 62-66). The dominant animals are burrowers and kangaroo rats. There are also insects, arachnids, reptiles and birds.
Another kind of desert, cold deserts, occurs in the basin and range area of Utah and Nevada and in parts of western Asia, where plenty of vegetation exist in the desert. Soils often have abundant nutrients because they need only water to become very productive and have little or no organic matter (Anderson, and Brubaker, 71-92). Typical plants include cactuses, acacias and short-lived annuals. Typical animals include reptiles and ground-dwelling rodents.
Deciduous forests can be found in the eastern half of North America, and the middle of Europe. There are many deciduous forests in Asia. Some of the major areas that they are in are southwest Russia, Japan, and eastern China. South America has two big areas of deciduous forests in southern Chile and Middle East coast of Paraguay (Anderson, and Ritchie, 573-596). There are deciduous forests located in New Zealand, and southeastern Australia also.
In deciduous forests there are five different zones. The first zone is the Tree Stratum zone. The Tree Stratum zone contains such trees as oak, beech, maple, chestnut hickory, elm, basswood, linden, walnut, and sweet gum trees. This zone has height ranges between 60 feet and 100 feet (Bard, and Rougerie, 241-244).
The small tree and sapling zone is the second zone. This zone has young, and short trees. The third zone is called the shrub zone. Some of the shrubs in this zone are rhododendrons, azaleas, mountain laurel, and huckleberries. The Herb zone is the fourth zone (Bartlein, and Barker, 417-424). It contains short plants such as herbal plants. The final zone is the Ground zone. It contains lichen, club mosses, and true mosses.
The deciduous forest has four distinct seasons, spring, summer, autumn, and winter. In the autumn the leaves change color. During the winter months the trees lose their leaves.
The animals adapt to the climate by hibernating in the winter and living off the land in the other three seasons. The animals have adapted to the land by trying the plants in the forest to see if they are good to eat for a good supply of food. Also the trees provide shelter for ...