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

WHAT IS AN ECOSYSTEM?

Let’s start with definitions from two of our key references:

“Any unit that includes all of the organisms (i.e., the community) in a given area interacting with the physical environment so that a flow of energy leads to clearly defined trophic structure, biotic diversity, and material cycles [within the unit] is an ecosystem.”  Odum (1971).

“An ecosystem can be defined as a functional system of complementary relations between living organisms and their environment, delimited by arbitrarily chosen boundaries, which in space and time appear to maintain a steady yet dynamic equilibrium.”  Gliessman (2007).