ECOLOGY- An Introduction

by

 

 

Ecology is  defined “as a scientific study of the relationship of the living organisms with each other and with their environment.”

The classical texts of the Vedic period such as the Vedas, the Samhitas, the Brahmanas and the Aranyakas-Upanishads contain many references to ecological concepts .The Indian treatise on medicine, the Caraka- Samhita and the surgical text Susruta-Samhita. contain classification of animals on the basis of habit and habitat, land in terms of nature of soil, climate and vegetation; and description of plants typical to various localities.

Caraka- Samhita contains information where air, land, water and seasons were indispensable  for life and that polluted air and water were injurious for health.

The environment is defined as ‘the sum total of living, non-living components;  influences and events, surrounding an organism.

Components of Environment

  1. Abiotic – Energy, Radiation, TEMP, Water, etc.
  2. Biotic- plants, animals, man, DECOMPOSER ETC.

Diesel engine exhaust fumes can cause cancer, humans” and it belong to the same potentially deadly category as asbestos, arsenic and ‘mustard gases.

Six main levels of organisation of ecology are:

  1. Individual- Organism is an individual living being that has the ability to act or function independently.
  2. Population-Population is a group of organisms usually of the same species,

occupying a defined area during a specific time,

  1. Community- Communities in most instances are named after the dominant plant form

(species). A community is not fixed or rigid; communities may be large or small.

Types of Community-

On the basis of size and degree of relative independence communities may be divided into two types-

(a)  Major Community

These are large-sized, well organized and relatively independent. They depend

only on the sun’s energy from outside and are independent of the inputs and

outputs from adjacent communities.

E.g: tropical ever green forest in the North-East

 

(b) Minor Communities

These are dependent on neighbouring communities and are often called societies.

They are secondary aggregations within a major community and are not therefore completely independent units as far as energy and nutrient dynamics are concerned.

e.g: A mat of lichen on a cow dung pad.

The environmental factors determine the characteristic of the community as well as the pattern of organisation of the members in the community

The characteristic pattern of the community is  termed as structure which is reflected in the roles played by various population, their range, the  type of area they inhabit, the diversity of species in the community and the spectrum of interactions between them

Eco-System-An ecosystem is defined as a structural and functional unit of biosphere consisting of community of living beings and the physical environment, both interacting and exchanging materials between them. It includes plants, trees, animals, fish, birds, micro-organisms, water, soil, and  people.

When an ecosystem is healthy (i.e. sustainable) it means that all the elements live in balance and are  capable of reproducing themselves

APSC Notes brings Prelims and Mains programs for APSC Prelims and APSC Mains Exam preparation. Various Programs initiated by APSC Notes are as follows:- For any doubt, Just leave us a Chat or Fill us a querry