Critical natural capital and the implications of a strong sustainability criterion.
Natural capital was defined as stocks and flows of energy and matter, and the physical states, such as climatic conditions or ecosystem characteristics, to which they give rise. Natural capital performs environmental functions. The importance of environmental functions was assessed in terms of the following criteria: maintenance of human health, avoidance of threat, and economic sustainability. On the basis of these three broad criteria, a number of principles of environmental sustainability were derived, related to current environmental issues of concern. The principles derive from the perception that, in order for the environment to be able to continue to perform its functions, the impacts of human activities on it must be limited in some ways. The natural capital which produces the environmental functions covered by these principles is designated critical natural capital (CNC). Measurements of the state of this CNC, and the pressures to which it is being subjected, may be used as indicators to show whether environmental sustainability-defined as the maintenance of important environmental functions-is being achieved. The levels of these indicators which correspond to the maintenance of important environmental functions are called sustainability standards. In the CRITINC project, natural capital itself was classified into four categories: air, water (marine and fresh, surface and underground), land/soil, and habitats (including ecosystems and the flora and fauna they contain). Using one classification system for the characteristics of natural capital, and another for the environmental functions to which they give rise, a framework matrix for classifying and assessing natural capital was developed. Incorporating the sustainability standards into this framework provides a means of showing the ‘gap’ between the current situation and environmental sustainability. The theoretical framework derived in the first phase of CRITINC was subsequently applied in two different ways (Results 2 and 3). First, each institute considered the framework as it related to its country’s natural capital as a whole, or to some aspect of the conservation of natural capital at a national level. Because the issues examined by each institute differed, so did the methodology adopted, and space does not here permit an explanation of each methodology and their differences. The papers covering some aspect of national natural capital are the Working Papers (WP) 2-7 inclusive, the topics of which are briefly described as follows: -SE: The importance of ecosystem performance to human well-being, and the limited extended to which this is reflected in Swedish national indicator systems of CNC (WP2). -IT: The procedures and decision-making processes through which CNC is defined and protected in Italy (WP3). -DE: The way in which the concept of CNC has been used in Germany in terms of the need to make a transition to environmental sustainability (WP4). -NL: The different methods which have been used to determine CNC (WP5). -FR: The cultural importance of natural capital and the societal implications of its degradation (WP6). -UK: An elaboration of the Framework with regard to the four principal components of natural capital (air, water, land, ecosystems), illustrated with UK data (WP7). Second, each institute applied the ideas underlying the framework in undertaking a case study of a particular environmental issue of domestic concern. The issues which provided the focus for the case studies were as follows: -UK: River systems of conservation interest. -France: Agricultural land and water resources. -Germany: Forests. -Italy: Air quality. -Netherlands: Coastal wetlands. -Sweden: Ecosystem functions in urban areas. Through these case studies the project showed that its approach to environmental sustainability may be fruitfully applied across a range of very different environmental issues, to generate insights into the extent and seriousness of environmental changes, what activities are responsible for them and the socio-economic implications of policies that would allow environmental sustainability to be attained.