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Unit 1: Basic Ecological Concepts and Principles Related to Agricultural Systems

The Energy Factor. In summary, ecosystems are organized, not chaotic, and they have an inherent structure based on the interrelationships of the various individuals and populations within the system. In addition, we can evaluate and describe that hierarchical structure in both natural and managed agriculture ecosystems.

But what is it that connects or holds the structure together? What factors govern the hierarchical relationships in an ecosystem?

Not surprisingly, energy is one of the most important factors governing ecosystem structure. The exchange and flow of energy in an ecosystem is described as its trophic structure, derived from the Greek word trofi, which refers to food or feeding. We’ll cover more about energy/food web relationships in Principle 3, but first let’s look more closely at some of the ways in which  ecosystem structure can be evaluated in both natural and agricultural systems.