The natural world is organized into interrelated units called ecosystems. Ecosystem is a collection of living and non-living organisms connected by a complex web of interactions. Ecosystem is a region in which the organism and the physical environment form an interacting unit.
For example weather affects plants, minerals in the soil and used by plants, plants affect animals, animals spread plant seeds, plants secure the soil and plants evaporate water which affects weather. Ecosystems sometimes have discrete and indistinct boundaries.
This is true in case of lake or island, transition from grassland to desert. It depends on the historical patter of rainfall in an area. Ecosystem look at the ways and means by which natural world is organized.
It answers to questions like-where do the rivers flow? What are the typical plants and animals in the area? How does human activity affect the nature? Environmental scientist recognizes and understands the natural interactions that take place.
Scientist integrates these in such a manner that men make use of this natural world. A few studies made from time to time illustrate this explanation.
North American continent is dominated by intensive agriculture. The original, natural ecosystems have been replaced by managed agricultural enterprise. Today it is difficult to find large regions of true wilderness.
The economic value generated by the use of rich soil is tremendous, and consequently most of the land is privately owned. Government cannot control easily what happens on these privately held lands, but do indirectly encourage certain activities.
It provides special subsidies to farmers and develops markets for products, lnspite of these facilities, economic risks involved in farming are great. Drought, disease and lack of markets result in failures the number of farmers constantly decline.
Not only this, many communities in this area rely on groundwater for drinking water which is contaminated due to the use of pesticides and fertilizers because they potentially enter the ground water.
In addition many farmeis use groundwater for irrigation which results in a lowering of the water level and less availability of groundwater for other purposes. To stay in this region, to do business and preserve way of life, farmers must make careful use of tools and technology in a responsible manner.
Irresponsible use cause increased erosion, water pollution and risks to humans. Environmental sciences teach perfect control and maintenance of ecosystem for living.