Ecology

Introduction •At one time, grasslands covered about 42% of the land surface of the world, today, however, much of it is under cultivation and its cover is reduced to 19% of the total land area of the world. •There are two main types of grasslands: 1.Grasslands variously known as Prairies (in North America); Veldt (in […]

Introduction •The freshwater habitats occupy a relatively very small portion of earth ‘s surface (i.e. 1% only) compared with marine (70%) and terrestrial habitats (28%), but their importance to humans is far greater than their area for the following reason. 1.They are the most convenient and cheapest source of water for domestic, agriculture and industrial

Introduction and Types •The word tundra is derived from a Finnish word “tunturi” meaning a tree-less plain. In Russian language tundra means a “marshy treeless landscape”. •There are two types of tundra’s. •a. Arctic Tundra: Some five million acres of Arctic tundra stretches across Canada, Northern Europe, Siberia and. Alaska encircling the North Pole. •b.

Introduction •With the world growing at a pace hard to match, the increasing need for space is turning out to be an area of concern. •With desperate need for land for agricultural, industrial and most importantly urban needs to contain cities and their growing population, a direct action that we have come to recognize as “Deforestation”

•An ecological niche is the role that a speciesplays and its position within the environment in which it develops; it is the way in which it manages to satisfy its food and shelter needs, how it survives and how it reproduces. •A species’ niche includes all its interactions with both bioticand abiotic factors in its environment. •Let us remember that biotic factors are all living beings, while

Introduction •Exotic and invasive species are two types of non-native species. Non-native species can be found in a second ecosystem apart from the ecosystem they evolved from. •Non-native species spread by natural process or human activities. Most non-native or indigenous species are harmless. They are called exotic species. •When an exotic species becomes harmful to

Introduction •Environmental law, principles, policies, directives, and regulations enacted and enforced by local, national, or international entities to regulate human treatment of the nonhuman world. •The vast field covers a broad range of topics in diverse legal settings, such as state bottle-return laws in the United States, regulatory standards for emissions from coal-fired power plants in Germany, initiatives in

Introduction •Community ecology deals with the groups of different kinds of populations in the area. •A community is defined as an assemblage of different plants, animals, and microbes living in a defined area of habitat. Thus, the forest with various kinds of trees, shrubs, herbs, animals (such as, mammals, birds, reptiles, insects, etc.) fungi and

Introduction •Humans need food as a source of energy and for tissue replacement, like any other animal. The source of much of the food consumed by man is terrestrial agriculture. •This represents the most manipulated of all the non-urban ecosystems, in which the energy and matter pathways are directed almost entirely to man and where

Introduction Pollution is an undesirable change in the physical, chemical or biological characteristics of our air, land, and water that may or will harmfully affect human life or that of desirable species, our industrial processes, living conditions, and cultural assets (Odum, 1971) In other words, pollution is the unfavorable alteration of our environment, largely as