v. 55

This wide-ranging text presents a synthesis of ideas emerging from 15 biome-specific workshops, each charged with the task of assessing our current knowledge of the effects of biodiversity on ecosystem processes. In all chapters the authors apply a broad definition of biodiversity, ranging from genetic to landscape diversity, thus providing a comprehensive assessment of the current situation. This assessment of the consequences of human activities at the ecosystem level is intended to assist in the development of an appropriate framework that can be used for making future policy decisions.

No 42

SCOPE is one of a number of committees established by a non-governmental group of scientific organizations, the International Council of Scientific Unions (ICSU). The mandate of SCOPE is to assemble, review, and assess the information available on man-made environmental changes and the effects of these changes on man; to assess and evaluate the methodologies of measurement of environmental parameters; to provide an intelligence service in current research; and by the recruitment of the best available scientific information and constructive thinking to establish itself as a corpus of informed advice for the benefit of centres of fundamental research and of organizations and agencies operationally engaged in studies of the environment. Rivers are the arteries of continents. They are the chief carriers of water, salt, organic matter, and mineral particles from land to sea. Continents on the other hand direct flow and composition of water in a number of ways. First, it is the height, the shape and the direction of mountain chains in relation to the weather front, which determines the size and water potential of a catchment area.
Second, rock type, climate and vegetation give characteristic imprints on the chemistry of the dissolved and particulate load of a river system. And third, the impact of humans on quality and distribution of water is felt in an ever increasing fashion. Ten years ago, and with the help of the SCOPE Community, an ambitious project entitled "Transport of Carbon and Minerals in Major World Rivers" was begun. The aim of this study was the assessment of riverine discharge of water, dissolved and particulate organic matter, nutrients and minerals into world oceans on local, regional and global scales. More than a hundred scientists and technicians from about 20 countries became engaged in this venture. The original data has been published in an eight-volume series which were the outome of SCOPE/UNEP Internatinal Workshops held since 1982. The present SCOPE Report "Biogeochemistry of Major World Rivers" is a kind of summary of the above volumes, plus a brief review of regional and general aspects of river systems. In order to make the topic transparent, only a few co-workers were asked by the editors to write a chapter.