Sustaining Geothermal Ecosystems: Thresholds of Change in Geothermal Ecosystems

Abstract

New Zealand has a range of geothermally-influenced ecosystems with distinctive ecological features and biotic communities. Retaining resilient geothermal ecosystems is an important goal of many communities and stakeholders, and is reflected in local, regional and national government policy and rules. An understanding of the real and perceived driving forces and pressures contributing to the sustainability of the natural resources of geothermal resources, and the thresholds at which the resource is no longer sustainable are necessary if management goals are to be met. Threshold values are points or zones of change from one ecological condition to another, usually from a natural or anthropogenic change in ‘pressure’ or ‘development’. In this paper we present the results of reviews and investigations that consider threshold values for ecologically sustainable geothermal ecosystems. Particular focus is given to the characteristics of geothermal resources. Threshold values can be used in sustainable planning or as goals for enhancement and restoration.