Question

Ecology of World's terrestial biomes history.

Answer 1

Ecology is the branch of biology that deals with the relations of organisms to one another and to their physical surroundings.

Biomes is define as a major biotic community characterized by the dominant forms of plant life and the prevailing climate.

The world's major land biomes  include tropical rain forest, tropical dry forest, tropical savanna, desert, temperate grassland, temperate woodland and shrubland, temperate forest, northwestern coniferous forest, taiga, and tundra.

1) Tropical forest -
The tropical forest biome is composed of several different sub-biomes, including evergreen rainforest, seasonal deciduous forest, tropical cloud forest, and mangrove forest. These sub-biomes develop due to changes in seasonal patterns of rainfall, elevate or reduce.

2.Savanna biomes -

Biomes are dominated by grasses and small trees. Savannas cover 60% of Africa and transition is seen from tropical forests to deserts. Trees in savannas are usually drought deciduous. Several savanna types associated with differing rainfall patterns, height of the water table and soil depth can be distinguished by their relative abundance of trees and grass.

3. Desert biome-

Here lot of variability is seen ranging from hot deserts, cold deserts, high elevation deserts, and rain shadow deserts. Subsequently, there is a great deal of variation in the biodiversity, productivity and organisms found in different types of desert.

4.Grassland biomes -

Many of the world’s largest terrestrial animals are found in grasslands. Animals like gray kangaroos (Macropus giganteus) in Australia, Bison (Bison bonasus) and horses (Equus spp.), grazing animals, their predators, and scavengers. Remnant herds in North America suggest that disturbances due to grazers increased local biodiversity by creating openings that rare species could colonize. Large grazers also accelerated plant decomposition through their droppings, creating nutrient hotspots that altered species composition.

5. Temperate deciduous forest biome -

The Biodiversity is relatively high in this biome due to the niche partitioning allowed by the multiple forest layers.These forests are associated with a greater number of animal species; for example, bird species diversity shows a positive correlation with forest height and number of layers.

6.Mediterrian climate biome -

This is a small biome, with hot, dry summers, and cool, moist winters . Unrelated evergreen, sclerophyllous shrubs and trees have evolved independently in each of these areas, representing a striking example of convergent evolution.

7.Northern coniferous forest -

This are Located at higher latitudes, dominated by needle-leaved, drought tolerant, evergreen trees and a climate consisting of long, cold winters and short, cool summers. Biodiversity is low in this two-layered forest made up of an overstory of trees and a ground layer of herbs or mosses. The overstory in much of the boreal forest is made up of only one or two species.

8.Tundra biome -

These are at latitudes beyond the boreal forest tree line lies a marshy area, where growing seasons are very short and temperatures are below zero degrees Celsius for much of the year . Because of these low temperatures and short growing seasons, net primary productivity is very low in the tundra.  Productivity varies with snowfall depth and local drainage. Rocky fields and dry meadows will have lower productivity than moist, low-lying areas and wet meadows.