Considering ecological thresholds in the environmental decision-making process – An argument for application of the precautionary principle.

Abstract

As human activities are now the greatest contributor to changes in Earth’s systems, the planetary boundaries framework seeks to define key ecological boundaries within which humanity is to develop in order to maintain the planet in a state conducive to planetary well being. Failure to do so presents catastrophic and potentially irreversible consequences for humanity. As uncertainty remains regarding the exact thresholds of the identified ecological systems as well as the consequences associated with surpassing them, the planetary boundaries framework provides for the adoption of a cautious approach through maintaining Earth’s systems at the lowest levels of identified risk. Despite the risks and uncertainty associated with transgressing ecological thresholds, evidence suggests that humanity has exceeded several planetary boundaries. This places critical Earth systems and processes in a zone of increasing and uncertain risk regarding the environmental consequences of human activities. As the planetary boundaries approach views the Earth as a single, complex and interconnected system, it is contended that non-global activities have implications for Earth’s systems and processes on a planetary level. Whilst the framework was not designed for direct application to decisions made at a project or activity level, the planetary boundaries framework holds value for decision makers insofar as it creates measurable, science-based criteria against which proposed activities can be considered for their effects on the safe operating spaces for humanity. The consideration of ecological thresholds has not formed an integral part of decision making at project or activity level. In the course of this dissertation, the case is made for the consideration of ecological thresholds through the application of the precautionary principle of environmental law. South Africa’s existing legislative framework obligates decision makers to consider and address uncertainty regarding the effects of an activity on the environment. It is argued that this requirement should extend to the impacts of activities on ecological thresholds. Through an analysis of both the interpretation and application of the precautionary principle by South African courts, an attempt is made to conceptualize a practical application of the suggested approach from the perspective of the decision maker.