FORESTS
Forests are large areas supporting rich growth of trees. Depending on the climate and type of trees they are generally grouped into:
- Tropical rain forests
- Temperate deciduous forests
- Boreal or north coniferous forests
(i) Tropical rain forest
- Distribution: These are found in the high rain fall areas on either side of the equator. Such forests are found in the western coast of India, scattered in south east Asia, some parts of Africa and south America.
- Flora and fauna: Tropical rainforests occur in areas by having high temperature and high humidity and receives above 200 cm of rainfall per year. Soil is rich in humus.
- These forests have a very rich biodiversity e.g. Brazilian tropical rain forests have more than 300 species of trees in an area of 200 square kilometer. Trees are tall growing upto 50 to 60 m. These forests also support epiphytes, like vines, creepers, woody creepers and orchid etc. These forests are rich in tree dwelling animals such as monkeys, flying squirrels, snails, centipedes, millipedes, and many insect species are common on the forest floor.
(ii) Temperate deciduous forests
- Distribution: They occur mostly in northwest, central and eastern Europe, eastern north America, north China, Korea, Japan, far eastern Russia and Australia. Trees of deciduous forests shed their leaves in autumn and a new foliage grows in spring.
- Climate: These forests occur in the areas of moderate climatic conditions such as temperature ranging but 10 to 20oC with a 6-month long winter and an annual rainfall between 75 to 150 cm. They have its brown soils which are rich in nutrients.
- Flora and fauna: Common trees are oak, beach, heath, chest nut, birch, pine. These forests also show stratification and have a under storey of saplings shrubs and tall herbs. Prominent grazers include deer, bison and rodents. Rodents play a very important role in these forests. They feed on seeds, fruits and tree leaves. Black bear, raccoons, wild cat, wolves, fox and skunks are the omnivores found in these forests. Hibernation or winter sleep during winter is a common feature of animals found in these forests. Invertebrate fauna comprises green flies, aphids, certain moths and butterflies.
(iii) Boreal or north coniferous forests:
- Distribution: Coniferous forests are also known as ‘Taiga’. They extend as a continuous belt across north America and north Eurasia below the arctic tundra. There is no counterpart of these forests in southern hemisphere as there is no land at this latitude. Climate is cold with long, harsh winter, with mean annual temperature below 00C. The soils are acidic and poor in nutrients.
- Flora and fauna: Coniferous forests are characterized by evergreen, drought resistant and woody. Conifers (gymnosperms) e.g. spruce, fir and pine trees which bear naked seeds in cones. The animals found in these forests, are red squirrel, deer, goat, mule, moose etc. The carnivores which feed upon them are timber wolves, lynxes, bear. Some common birds are crossbill, thrushes, warblers, flycatchers, robin and sparrow.
