The group of organism interacting among themselves and with their environment in the forest is called as forest ecosystem. Forest occupies about forty percent of the land. In Nepal, the forests occupy about twenty-five percent of the total land area. The different components of the forest ecosystem are as given below:
These are the inorganic as well as organic substances present in the soil and atmosphere. In addition to the minerals present in the forest, we find the dead organic debris the litter accumulation, chiefly in a temperate climate. Moreover, the light conditions are different due to complex stratification in the plant communities.
The biotic component of forest ecosystems are as given below:
These are those living members of an ecosystem which synthesize food from an inorganic substance. These are mainly trees that show much species diversity and the greater degree of stratification, especially in the tropical moist deciduous forest.
Consumers are those living members of an ecosystem which obtain food from producers and others. These are as follows:
a) Primary Consumers:
These are the Herbivores that include animals feeding on tree leaves as ants, flies, beetles, leafhopper, bugs, and spiders etc. and larger animals grazing on shoots or fruits of producers, the elephants, nilgai, deer, fruit bats, mongooses etc.
b) Secondary Consumers:
These are the carnivores like snakes, birds, lizards, fox etc. feeding on herbivores.
c) Tertiary Consumers:
These are the top carnivores like lion, tiger etc. that eat carnivores as well as herbivores of primary and secondary consumers level.
These are the wide variety of microorganisms including fungi, bacteria and actinomycetes rate of decomposing in tropical and subtropical forests is more rapid than that in the temperate ones.
Forest is a relatively large area of closely canopied trees, forest occupies roughly forty percent of the land. But in the context of Nepal, forest occupy only about twenty-six percent of the land, so we can’t say that Nepal is rich in a forest ecosystem. In Nepal, tropical forest ecosystem consists of northern coniferous forest, temperate deciduous forest, tropical rainforest and Mediterranean sub-forest. The following are the characteristics features of tropical forest ecosystem:
It is a bottom to the top spatial configuration of above ground within a forest stand. It generally includes the following strata.
The effect exerted by the adjoining community on the population structure within the marginal zone.
It is the change in the spatial configuration of forest in which formerly continuous forest areas turned into small strands. This results from disruption of continuity. Its effects are:
Our environment comprises many organisms’ producers, consumers, and decomposers. These all play vital for the continuity of ecosystem producer takes their nutrition from different sources like light from the sun, water and organic nutrition from soil and this material is transported to the different producer levels and finally to the soil. The vital role of decomposer exists here. The decomposer decomposes the material and then stored in the soil. If there were no decomposer then the energy be a disturbance in the ecosystem causing discontinuities in energy flow so decomposers are the major component of the environment.
Decomposer is important in ecosystem since they take an important part in biogeochemical cycling and another many process. The important nutrients locked in the biomass of plants and animals become incorporated into the soil and water through the action of decomposer called as ‘mineralization’ process. The microbial activities of decomposers convert the minerals and other useful nutrients into the forms that can be readily taken up by plants and other producers. For example, the leaf litter is converted into organic matter, like humus, rich in nutrients through a decomposition process. The toxic and harmful Materials are converted into relatively nonharmful and even useful minerals known as detoxification. So that in one hand toxicity of the chemicals in the environments is reduced. On the other hands, the plants are supplied with nutrients. The role of decomposers is greatly significant in the natural systems of nutrient deficiency because the decomposer can release the nutrients otherwise impossible to supply the plants with.
The group of organisms interacting themselves and with the grassland is called grassland ecosystem. Grassland occupies a comparatively few area, roughly nineteen percent of the earth’s surface. The components of grassland ecosystem are as follows:
These are the nutrients present in the soil and the aerial environment. Thus the element like C, H, O2, N, P etc. are supplied by CO2, H2O, NO2, PO4, SO4, etc. present in the air and soil of the area. Moreover, in addition to the above, some trace elements also present in the soil.
These biotic components are further categorized as:
The herbivores feeding on grasses are mainly such grazing animals as cows, buffaloes, deer, sheep, goats, rabbit, mouse, etc. Besides them there also some insects such as Septoria, Dysdercus, Oxyrhynchus, Cicincella, some termites, and Millipedes etc. that feed on the leaves of grasses.
These are the carnivores feeding on herbivores. These include the animal like a fox, jackals, snakes, frogs, lizards, etc. sometimes the hawk feed on the secondary consumers, thus occupying tertiary consumers level in the food chain.
The microbes active in the decay of dead organic matter of different forms of higher life are fungi, as species of mucor Aspergillus, Penicillium, Cladosporium, Rhizopus, Fusarium etc. and some bacteria and actinomycetes. They bring about the minerals back to the soil, thus making them available in the producers.
E.p., Odum. Fundamentals of Ecology. USA: W.B Saunters Company, n.d.
Jr., Miller G.T. Living in the Environment. Belmont, California,USA: Wadsworth Publishing Company, 2003.