Environmental rehabilitation of damaged land

Abstract

Background: Much land is subject to damage by construction, development and exploitation with consequent loss of environmental function and services. How might the loss be recovered? Results: This article develops principles of environmental rehabilitation. Key issues include the following. Rehabilitation means restoring the previous condition. Whether or not to restore is not a technical but a value judgement. It is subject to adopting the sustainability ethic. If the ethic is followed under rule of law then rehabilitation must be done always to ‘the high standard’ which means handing down unimpaired environmental function and no extra land management. The elements of the former condition that it is intended to restore must be specified. Restoring these in any given case is the purpose of that rehabilitation project. The specified restoration elements must be easily measurable with a few simple powerful metrics. Some land damage is not fixable so restraint must be exercised in what construction, development and exploitation are permitted. If sustainability is adopted then cost benefit analysis is not a valid form of project appraisal because trading off present benefits against future losses relies on subjectively decided discount rates, and because natural capital is hard to price, indispensable, irreplaceable and non-substitutable. Elements often to be restored include agricultural land capability, landscape form and environmental function. Land capability is a widely used convention and, with landscape form, encapsulate many key land factors, and are easily measurable. Restoring soil and thereby environmental function provides the necessary base for an ecological pyramid. Conclusions: The need for rehabilitation is not to be justified by cost-benefit or scientific and technological proof, but rests on a value judgement to sustain natural capital for present and future generations. Decision on what activities and projects to permit should be based on what is physically and financially fixable on current knowledge. Business and government must be proactive, develop rehabilitation standards, work out how to meet the standards, design simple powerful metrics to measure performance against the standards, embark on continuous improvement, and report.