PART 5: How do soil organisms interact with each other?

Introduction

There are an enormous number of interactions between species comprising the soil community. An example of one type of interaction is when organisms either concurrently colonise or simultaneously exclude each other during the breakdown of organic matter in the soil. Because soil organisms respond in different ways to environmental changes, the interactions between soil organisms are continually dynamic.

Understanding how soil organisms interact requires an understanding of their individual lifecycles, which may be quite different and complex. Furthermore, knowledge is needed of:

(i) how disturbance regimes affect individual organisms, and

(ii) how disturbance regimes affect the way that organisms contribute collectively to soil processes.

Intricate links occur between some organisms in the soil but the extent of these can only be guessed. The most obvious link is through foodwebs (Coleman et al. 2004). Soil animals feed on fungi and bacteria and other soil animals, altering the relative abundance of species within the dynamic food-web.

There are many fascinating studies that provide insight into the kind of interdependence that occurs between organisms in soil. However, it is impossible to present information on all the interactions that occur between soil organisms. In this section, examples are used to demonstrate several types of interactions and to provide an overview of the types of interactions that occur.