Aspects Of Ecosystem
The ecosystem can be defined as any spatial or organizational unit including living organisms and non-living substances interacting to produce an exchange of materials between the living and non-living parts. The ecosystem can be studied from either structural or functional aspects.
The structural aspects of the ecosystem include a description of the arrangement, types, and numbers of species and their life histories, along with a description of the physical features of the environment.
The functional aspects of the ecosystem include the flow of energy and the cycling of nutrients.
The non-living part of the ecosystem includes different kinds of habitats such as air, water and land, and a variety of abiotic factors. Habitat can be defined as the natural abode or locality of an animal, plant or person. It includes all features of the environment in a given locality. For example, water is used as a habitat by aquatic organisms and it comprises three major categories-marine, brackish and freshwater habitats. Each of these categories may be subdivided into a smaller unit, such a freshwater habitat may exist as a large lake, a pond, a puddle, a river or a stream.
The land is used as a habitat for numerous terrestrial organisms. It includes many major categories of landmasses, which are called biomes. Biomes are distinct large areas of earth inclusive of flora and fauna, e.g. deserts, prairie, tropical forests, etc. Soil is also used as a habitat by a variety of microbes, plants, and animals.
Among the main abiotic factors of the ecosystem are included in the following:
- The climatic factors as solar radiation, temperature, wind, water currents, rainfall.
- The physical factors as light, fire, pressure, geomagnetism,
- Chemical factors as acidity, salinity and the availability of inorganic nutrients needed by plants.
Biotic or Biological Factors
The biological (biotic) factors of the ecosystem include all the living organisms-plants, animals, bacteria and viruses. Each kind of living organism found in an ecosystem is given the name of a species. A species includes individuals who have the following features:
- They are genetically alike.
- They are capable of freely inter-breeding and producing fertile offsprings.
In an ecosystem, there exist various relationships between species. The relationship may be as under:
Two species may have any of the following kind of effects:
- They may have a negative effect upon one another (competition)
- They may have a neutral effect (neutralism).
- They may have a beneficial effect (protocol operation and mutualism).
Other kinds of Relationship
The species may aggregate, or separate, or show a random relationship to one another.
A population is a group of interacting individuals, usually of the same species, in a definable space. In this way, we can speak of the population of deer on an island, and the population of fishes in a pond. A balance between two aspects determines the size of a population of any given species:
- Its reproductive potential,
- Its environmental resistance.
In this way population size is determined by the relative number of organisms added to or removed from the group as under:
Recruitment into the population is a function of birth rate and immigration rate.
Loss from the population is a function of death rate and emigration.
Factors Regulating Population
Following factors does population regulation:
- Physical attributes of the environment (e.g. climate)
- Food (quantity and quality),
- Disease (host-parasite relationships)
- Competition (inter-specific and intra-specific).
An ecosystem contains numerous populations of different species of plants, animals, and microbes; all of them interact with one another as a community and with the physical environment as well. A community or biotic community, thus, consists of the population of plants and animals living together in a particular place.
This post contains the content of the book Environmental_Science by Dr. Y. K. Singh below is the link of complete book Environmental_Science