Processes in the ecosystem

Abstract

A biological community is a collection of organisms living together. There are two main features of communities, that raise them above the level of mere chance associations of unrelated individuals. Firstly, interactions such as predator-prey, mutualism, parasitism, and competition are more frequent within the community, than between its members and those of neighbouring communities. Interactions do occur with other communities. Rabbits which live in clumps of gorse emerge to feed on crops growing beside them, see Figure 33. Rooks carry elements such as nitrogen and phosphorus, eaten as part of their food in the fields, and deposited in their droppings on the ground beneath their nests. Such examples, though common, represent only very few interactions compared to the closely knitted web within.