In a marvelous way all the living, non living and climatic conditions of a place are interconnected and a geographical area along with this interconnected network is termed as an “Ecosystem”. Ecosystems differ in flora, fauna and weather but all of them support some kind of life. Therefore, it is very important to understand the features of the ecosystem before entering it and trying to make changes. It was lack of this understanding in early days that led to exploitation of the natural habitats and extinction of many rare species along with destruction of some beautiful landscapes. There are many important energy and matter transformation cycles that run through these ecosystems. Human beings are known to act in manners which disrupt these cycles and disrupt the natural flow of things in an ecosystem. This leads to major problems in the ecosystems as links of cycles get detached and stability of the system is lost. To prevent this from happening we need to understand what type of ecosystem we are dealing with. This is just a brief introduction to a subject which requires in depth study.
Different Kinds Of Ecosystem
There are basically two types of ecosystems; Terrestrial and Aquatic. All other sub-ecosystems fall under these two.
Terrestrial ecosystems are found everywhere apart from water bodies. They are broadly classified into:
The Forest Ecosystem
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. You can see wonderful diversity in the fauna of these ecosystems too. 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.
The Desert Ecosystem
Desert ecosystems are found in regions receiving an annual rainfall of less than 25cm. They occupy around 17 percent of all land on the planet. Due to very high temperature, intense sunlight and low water availability, flora and fauna are very poorly developed and scarce. Vegetation is mainly bushes, shrubs, few grasses and rarely trees. Leaves and stems of these plants are modified to conserve water. The best known desert plants are the succulents like spiny leaved cacti. Animal life includes insects, reptiles, birds, camels all of whom are adapted to the xeric (desert) conditions.
The Grassland Ecosystem
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:
1. Savanna: These tropical grasslands are seasonally dry with few individual trees. They support large number of grazers and predators.
2. 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.
The 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.
The Marine Ecosystem
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.
- 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.
The Freshwater Ecosystem
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.