The living organisms are influenced by a large number of environmental factors. These environmental factors are known as ecological factors or eco-factors.
These factors may be biotic (living) or abiotic (non-living). All the environmental factors bring marked distributional, structural and functional changes in living organisms. To live, grow and carry out all its activities, the organisms require a harmonious relationship with their environment. The differences in vegetation of a desert and a rain forest, plants in a pond and grassland, animals in tropical countries and cold countries, clearly indicate the role of environmental factors in the distribution and survival of organisms in different eco-systems.
Major ecological factors can be classified into:
Climatic factors:
(a) light (b) temperature (c) rainfall (d) wind (e) humidity (f) pH. A variation in one or more of these factors affects the distribution and lifestyle of organisms.
Topographic factors:
(a) Altitude (b) slope and direction of mountain chain and valleys.
Edaphic factors:
Structure, formation and characteristics of different types of soils.
Biotic factors:
These are derived from the interactions between different species of living organisims (intra-specific as well as inter-specific).
