Towards the Assessment of Environmental Sustainability in Forest Ecosystems: Measuring the Natural Capital

The present use of the world's forest resources is not sustainable. Yet over-harvesting and other stresses on forest ecosystems continue to degrade this natural capital on which human welfare is built. To improve information about forest resources to policy makers and the public at large, we propose the formulation of an index for the natural capital of forests that portrays the status and trends in the level of environmental sustainability of forests. The index and the sub-indices on which it will be based should reflect the composition, structure and functions of forests within a landscape perspective. The index should take into account forest ecosystems, ranging from naturally dynamic forests, cultural woodland to previously forest dominated landscapes, which have become highly degraded or transformed to other uses. Comparisons of quantitative and qualitative measurements, or indicators, with ecologically based performance targets, should be used to evaluate resource sustainability. The index could thus serve as a composite measurement of the quality of stewardship of the global forest capital, and signal to the world community its progress, or lack thereof. A natural capital index for forests is a logical next step after a sequence of international initiatives during the last two decades in support of sustainable management of the world's forest resources. The development of an index should proceed by: 1) selecting indicators measuring the status of forest resources and services in actual landscapes; 2) developing performance targets by systematic research and synthesis; 3) aggregating the chosen indicators and targets into a regularly updated index; 4) applying the chosen methodology in a series of pilot studies in countries with different types of forest ecosystems and phases in the development of the use and management of forests; 5) studying the institutional arrangements needed for gathering, keeping and updating data over time and facilitating its adoption in national forest policies and programmes; and 6) assessing changes in the index over time.