An ecosystem consists of the biological community that occurs in some locale, and the physical and chemical factors that make up its non-living or abiotic environment. There are many examples of ecosystems a pond, a forest, an estuary, a grassland. The boundaries are not fixed in any objective way, although sometimes they seem obvious, as with the shoreline of a small pond. Usually the boundaries of an ecosystem are chosen for practical reasons having to do with the goals of the particular study. The study of ecosystems mainly consists of the study of certain processes that link the living, or biotic, components to the non-living, or abiotic, components. Energy transformations and biogeochemical cycling are the main processes that comprise the field of ecosystem ecology. As we learned earlier, ecology generally is defined as the interactions of organisms with one another and with the environment in which they occur. We can study ecology at the level of the individual, the population, the community, and the ecosystem. Types: There are basically two types of ecosystems; Terrestrial and Aquatic. All other sub-ecosystems fall under these two. Terrestrial ecosystems: Terrestrial ecosystems are found everywhere apart from water bodies.
These are the ecosystems where abundance of flora (plants) is seen and they have a large number of organisms living in relatively small areas. Therefore, the density of life in forest ecosystems is very high. Any small change in the ecosystem can affect the whole balance and collapse the ecosystem.They are again divided into few types. Tropical evergreen forest: Tropical forests which receive an average rainfall of 80 to 400 inches in a year. These forests are marked by dense vegetation comprising of tall trees with different levels. Each level gives shelter to different kinds of animals. Tropical deciduous forest: Dense bushes and shrubs rule here along with broad levels of trees. This type of forests is found in many parts of the world and large variety of flora and fauna are found here. Temperate evergreen forest: These have very few number of trees but ferns and mosses make up fro them. Trees have spiked leaves to minimize transpiration. Temperate deciduous forest: This forest is found in the moist temperate regions with sufficient rainfall. Winters and summers are well defined and with trees shedding their leaves during winter.Taiga: Situated just south of the arctic regions, Taiga is distinguished by evergreen conifers. While the temperature is subzero for almost six months, the rest of the year it is buzzing with insects and migratory birds.
Grasslands are found in both temperate and tropical regions of the world but the ecosystems are slightly varying. This area mainly comprises of grasses with very little amount of shrubs and trees. Main vegetation is grasses, legumes and plants belonging to composite family. Many grazing animals, herbivores and insectivores are found in grasslands. Two main types of grasslands ecosystems are: Savanna: These tropical grasslands are seasonally dry with few individual trees. They support large number of grazers and predators. Prairies: This is temperate grassland. It is completely devoid of trees and large shrubs. Prairies can be categorized as tall grass, mixed grass and short grass prairie.
Mountain Ecosystem: Mountain lands provide a scattered but diverse array of habitats in which a large range of plants and animals are found. At higher altitudes harsh environmental conditions generally prevail, and only treeless alpine vegetation is found. The animals living here have thick fur coats fro prevention from cold and hibernate in winter months. Lower slopes commonly are covered by coniferous forests.
An aquatic ecosystem is an ecosystem located in a body of water. It comprises aquatic fauna, flora and the properties of water too. There are two types of aquatic ecosystems, Marine and freshwater.
Marine ecosystems are the largest ecosystems with coverage of nearly 71% of the Earth\'s surface and containing 97% of the planet\'s water. The water in Marine ecosystems has salts and minerals dissolved in them in high amounts. Different divisions of marine ecosystems are: Oceanic: The relatively shallow part of the ocean that lies over the continental shelf. Profundal: Bottom or deep water. Benthic Bottom substrates. Inter-tidal: The area between high and low tides. Estuaries, Salt marshes,Coral reefs. Hydrothermal vents-where chemosynthetic bacteria form the food base. Many types of organisms are found in marine ecosystems including brown algae, dinoflagellates, corals, cephalopods, echinoderms, and sharks.
In contrast to the Marine ecosystem, freshwater ecosystems only cover 0.8% of the Earth\'s surface and contain 0.009% of its total water. There are three basic types of freshwater ecosystems: Lentic: Still or slow-moving water like pools, ponds, and lakes. Lotic: Fast-moving water like streams and rivers. Wetlands: Places where the soil is saturated or inundated for at least some time. These ecosystems are home to amphibians, reptiles and almost 41% of world\’s fish species. Faster moving turbulent water typically contains greater concentrations of dissolved oxygen, which supports greater biodiversity than the slow moving water of pools.