Identifying ecological threshold breaches in wetlands: Development of a framework to improve wetland prioritisation and restoration in South Africa

Authors:
Damian Walters

Publication Date:
2019

Abstract/Summary:
Thresholds in ecology refer to a point where even a small change in conditions can lead to a shift in an ecosystem to an alternative ecological state. Once a threshold has been crossed, an ecosystem may not easily return to its pre-threshold state and, as a consequence, this may result in a change in composition, structure, and functionality. When assessing a wetland ecosystem for the purposes of planning restoration it is essential to develop an understanding of ecological thresholds and the resilience of the system in its present state. If basic processes such as hydrology, geomorphology, and vegetation community dynamics are highly altered, it may be prohibitively expensive or even impossible to restore the system. In contrast, a less degraded system that has yet to breach a threshold may be a better candidate given that it has better restoration potential. We present an overview of the development of an assessment framework and indicators that can be used to identify thresholds in degraded wetlands and assess their significance to the restoration potential of the wetland. The framework considers thresholds of change in relation to three important components of wetlands, namely hydrology, geomorphology, and vegetation community dynamics and provides a set of field-based indicators that can be used to identify thresholds.

Resource Type:
Audio/Video, Conference Presentation, SER2019

Pre-approved for CECs under SER's CERP program

Source:
Society for Ecological Restoration