Introduction

Figure 1

Ecosystems comprise more than relationships between organisms in the habitat. They are affected by factors such as light, water, carbon dioxide and nutrients and, of course, human activity.

It is nearly impossible to understand all the interactions occurring in a given ecosystem at any one time, but it is possible to observe the types of interactions that are present – and there are six, described by Dr Mike Gillman in the following video. Analysing interactions in terms of these types can help to define the boundaries of a system, though this is not an easy task. Dr Vincent Gauci considers the routes of energy loss in ecosystems.

Transcript