Skip to main content

Basic Concept of Ecology (II)

                                                           Ecosystem

When both, biotic and abiotic components are considered , the basic structural and functional units of nature are ecosystem. Ecosystem was adopted as the unit of ecological studies. Tansley (1935) thus emphasized the role of environment, with its various factors interacting with each other in his comprehensive term ecosystem. 

       Each population occupies a specific niche, a unique functional position with respect to other organisms with which it interacts. Particular population has within a given habitat. Population ecologists study interactions at population as well as community level. They study competition, usually between populations from the same trophic level ( such as herbivores competing for the same grass i.e., population ecology involving individuals of same species ), and  prey-predator interactions between members of adjacent trophic levels ( i.e., population ecology involving interactions between individuals of different species, at community level).

       Also, there are involved energetics of ecosystem. The radiant energy is trapped by the autotrophic organisms (producers) and is transferred as organic molecules to the heterotrophic organisms (consumers). This energy flow is uni-directional or non-cyclic. 

       The chemical components of the ecosystem move in defined cycles - biogeochemical cycles. Role of water as the universal solvent for biological systems is much relevant here. Successful growth of the organism is governed by limiting factors. The minimal and maximal levels of tolerance for all ecological factors of a species vary seasonally , geographically and according to the age of the population. 

                                                          Succession

The dynamic environment and organisms make ways for the development of different kinds of organisms through a process known as succession. The process continues till the development of a community which is now more or less stable and is now able to keep itself adjusted in equilibrium with the environment. This final stage of community is called a climax. 

         The various forms of a species, in order to meet the challenge of changed environment , may arise by virtue of somatic plasticity, the ecads, or by the reorganisation of their genes during sexual reproduction, the ecotypes. Thus species may increase their capacity of tolerance towards changing environment by developing ecads and ecotypes. Succession is thus an ecological phenomenon of replacement of an earlier ecosystem by a higher biomass-rich and trophically -diversified ecosystem.  

           Then come to the probabilities of disruption and exploitation of ecosphere. It leads to a set back to the state of development and reduction in the stability of the ecosystem. Man's exploitation of ecosystems is directed towards channeling productivity to his needs. 

          Applied ecology or human ecology is the use of ecological concepts to describe human activities and the determination of ways in which people can best obtain their needs from ecosystems. Ecosystems which are substantially altered by human activities are called managed, whereas those free from such disturbances are the natural ones. 





                                                               Conservation

        Ecological conservation is a necessity of  life systems. It involves continuity of the dynamic ecosystem. Regulation of populations through naturally-operating trophism ensures resilience or homeostasis of the system. It brings about diversity and stability within the structural and functional flux. Species diversity increases the production efficiency of the system whereas dominance makes the system stable, though less efficient for production. Interspecific competition results into dominance by a limited number of species. 

       If we could balance first conservation against consumption of natural resources, we would be able to restore the health of our degrading environment. Conservation occupies central importance in solution of environmental problems of global warming and climate change, atmospheric pollution and loss of biodiversity.

Location: Kolkata, West Bengal, India

Comments

Post a Comment

Popular posts from this blog

Approaches to Ecology : Its Main Subdivisions and Developmental Facets

 A perusal of the developmental history of ecology reveals that ecological studies made from time to time are based upon three principal aspects --- i. Taxonomic affinities, ii. Habitat and iii. Levels of organisation. Accordingly, these approaches could lead to the development of the following main subdivision of ecology.  Based On Taxonomic affinities : In early days of ecology, botanists and zoologists engaged themselves separately in the study of ecology of plants and animals respectively. This led to the development of such sub-divisions are as plant ecology and animal ecology .  However, modern ecologists feel that the principles in the study of plants and animals are not only much similar, but these two great groups of organisms are very much inseparably interrelated with each other. Thus, modern ecology prefers not to make much distinction between ecology of plans and animals. The term ecology indeed includes the interrelationships and interdependencies of all...
Post a Comment
Read more

What is Environment ?

 Environment has different meaning for different people. Most definitions include the physical, chemical and biological components that influence the life of an organism. All the external factors, conditions and influences that effect an organism or a biological community i.e. known as environment.  The term environment etymologically means surroundings . The place, where an organisms lives - habitat , indeed presents a particular set of environmental conditions - the environmental complex . Thus, environment is a complex of so many things i.e. light, air, soil, water, temperature etc have been variously called as environmental factors , ecological factors or may be living i.e biotic factors (plants, animals, microorganisms etc.) and non-living i.e. abiotic factors .   Daubenmire (1959) classified the factors into seven coordinate headings as i. soil, ii. water, iii. temperature, iv. light, v. atmosphere, vi. fire and vii. biotic factor .  Most of the ec...
Post a Comment
Read more

ECOLOGY IN INDIA

 During the first third of 20th century , there started to develop such specialised areas of ecology as paleo-ecology, zoogeography, oceanography, limnology  etc., and  then was introduced the population concept on which statistical studied and sampling techniques were employed for solving the community problems. this era is popularly called as era of population and community ecologist .  Ecological studies during the first half of the 20th century could make it evident that humans are an integral part of the complex ecosystem ' the ecosphere ' and how anthropogenic activities disrupted the ecological processes leading to degradation of the environment that affected the humans as much as other forms of life, plants, animals and microbes. We are facing the greatest challenge to our intellect and wisdom for saving the humanity from extinction. It has arisen from our activities constricting the environment and depleting the natural resources of biosphere, specially so ...
Post a Comment
Read more