Submitted to: Soil Quality and Soil Erosion
Publication Type: Book / Chapter
Publication Acceptance Date: October 1, 1997
Publication Date: N/A
Technical Abstract: The relationships between rangeland soil quality, soil resilience and soil erosion depend on several interacting factors: 1) landscape and climate characteristics, 2) current disturbance regime and 3) recent and evolutionary disturbance history. Soil quality is defined as the capacity of a soil to perform functions which sustain biological productivity and maintain environmental quality. Soil resilience is the capacity of the soi to recover functions following disturbance and is distinguished from soil resistance, which is its capacity to maintain those functions without change through a disturbance. Within the context of a particular ecosystem, there are at least 4 specific relationships between soil quality and soil erosion which involve soil resistance or soil resilience. The first is historical resistance of soil to past disturbances, which can serve as an indicator of soil quality. Secondly, current resistance of soil to disturbance is related to soil erosion potential. This indicator of soil quality has been developed through predictive models such as WEPP. Third is current resilience of the system following soil erosion. Finally, soil erosion is a driver in the system which determines soil quality. This illustrates the need to view the system dynamically: soil erosion reflects and affects soil quality. These relationships depend on the characteristics of historic and current disturbance regimes. Ecosystems and species tend to evolve in response to dominant disturbance regimes such as fire, drought and grazing. Key characteristics of disturbance regimes include type, spatial scale, frequency, intensity and predictability. The resistance and/or resilience of the system tend to be higher for disturbance regimes which share key characteristics with historic and evolutionary patterns.