Regime shifts are defined as large, persistent changes in the structure and function of ecosystems, with substantive impacts on the suite of ecosystem services provided by these systems. A large number of regime shifts have been documented globally, including lake eutrophication, shifts to algae-dominated coral reefs, and bush encroachment. However, the exact thresholds at which these shifts occur are seldom known, and often vary somewhat depending on local conditions. Thus the risk of a particular regime shift in a particular place is often unknown.
This study aims to develop a method for mapping resilience to regime shifts and assessing the economic value of resilience, using the case of bush encroachment. The method for mapping resilience to regime shifts and assessing the economic value of this resilience will be developed by mapping and modelling the occurrence and resilience to bush encroachment in KwaZulu-Natal. This regime shift can be detected using remote sensing products which we will use to develop a method for assessing the likelihood of a shift.
This study will contribute three main products: 1) a method for mapping resilience to regime shifts, that could be potentially be used to assess resilience to other types of regime shifts that can be detected in spatial data ; 2) a probabilistic map of resilience to bush encroachment in the Eastern Cape, which could be used to inform land management policies in the province, and 3) an economic assessment of the “insurance” value of resilience to bush encroachment, that can be used to inform policy trade-offs in the region. The project will also contribute improved information on bush encroachment regime shifts to the Regime Shifts Database (www.regimeshifts.org). The results of this research will help better understand key drivers of bush encroachment in southern Africa, and determine how ecosystem services changes before and after regime shifts in bush encroachment.
