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

Boundaries: Delineating Ecosystems

(Photo by Graham Cook, CC BY 2.0)

Think  about a natural area you may have visited recently: How would you define the boundaries of that ecosystem? The boundaries of natural ecosystems are usually blurred, without well-defined edges. Forests blend into shrub lands, which blend into savannahs, into tall grasslands and then into short grasslands. Even in coastal ecosystems, what can look like a sharp line between water and land is usually a transitional zone created by the influence of sand, tides, waves and the unique species that live there. Transitional zones between natural areas are called ecotones (learn more about Ecotones).

Agroecosystem boundaries, on the other hand, are usually more clearly delineated, often with distinct edges. Keep in mind, though, that a distinct boundary line does not imply a barrier or division. Adjacent ecosystems, farms and ranches are connected and interact with each other through the movement of air, soil, water, chemicals, living organisms such as mammals, insects, birds and microorganisms, and plant materials such as pollen, seeds or fruits.