The study of the inclusive nature society dealing with interactions of organisms with other organisms and with the physical environment.
All the organism within an area belonging to the same species.
The number of individuals of a certain species per unit area or volume.
The pattern of dispersal of them within that area.
The number of individuals in a population.
The probability of newborn individuals of a cohort surviving to particular ages.
All the various populations interacting in an area counted as a whole.
Composition of a community
A listing of the various species in the community.
Diversity of a community
More complex than the composition of a community in that it involves both species richness(the number of species) as well as evenness (the relative abundance of different species).
An environment wherein an organism lives and reproduces.
The functional role the organism plays in its community, including its habitat as well as the interactions with other organisms.
It occurs when members of different species try to utilize the same resource like light, space, or nutrients that is in limited supply, or when their niches overlap.
One organism, called the predator feeds on another, called the prey.
One in which members of two populations interact very closely.
This indicates a situation wherein an organism called a parasite derives nourishment from another called the host.
One species is benefited and the other is neither benefited or harmed.
A symbiotic relationship in which both species benefit
An ecosystem extends a community by involving also the abiotic environment, that is, the physical and chemical environment.
Such physical and chemical factors of an ecosystem as light, temperature, atmosphere gases(nitrogen, oxygen, carbon dioxide are the most important), water, wind, soil.
Organisms that produce their own organic nutrients for themselves and other members of the community
Consumers that are unable to produce, are constantly looking for source of organic nutrients from elsewhere.
Organisms that rely on detritus, the decomposing particles of organic matter, for food.
The term used to describe the amount of organic matter an ecosystem produces from solar energy within a given area during a given period of time.
Gross primary productivity
The total amount of organic matter produced by all autotrophs in an ecosystem, including that used by themselves.
Net primary productivity
The total amount of energy fixed per unit of time minus the amount of energy expended by the metabolic activities of the photosynthetic organisms in the community, denoting the amount of organic matter produced by autotrophs that is available for heterotrophs.
The net weight of all organisms living in an ecosystem, which, increases as a result of its net production.
The rate of biomass accumulation by heterotrophs (herbivores, carnivores and detritivores).
The complicated feeding relationships that exist among organisms in natural ecosystem.
All the organisms that feed at a particular level in a food chain.