This Special Issue of Water, Air and Soil Pollution offers original contributions from BIOGEOMON, an international symposium on ecosystem behavior and the evaluation of integrated monitoring of small catchments, held in Prague, Czech Republic, in September 1993. The meeting attracted nearly 200 scientists from 27 countries on five continents. BIOGEOMON was a loose continuation of another international meeting, GEOMON, which was held in Prague in 1987. Both sym posia provided a forum for the discussion of ideas on environmental problems in western and eastern Europe, with important contributions from the American continent. With the dramatic collapse of the iron curtain, it was our hope that more so than GEOMON, BIOGEOMON would provide opportunities for the free exchange of ideas, fostering the development of research collaborations between its participants. With international openness comes the increasing realization that every indus trialized nation has its own legacy of environmental degradation. Anthropogenic impacts differ in severity and scale; air and water transport of pollutants transform local impacts into regional and global ones, ignoring political boundaries and eco nomic differences. Environmental consequences of anthropogenic activities often are detectable at the ecosystem level. Thus, the challenge of ecosystem science, and to the individuals who practice it, is to develop a comprehensive understanding of ecosystem function in the past and at present, and to apply such understanding toward minimizing future insults to the local, regional, and global environment.

The purpose of this book is to analyse and discuss a series of topics related with environmental conservation, land-use planning and management and impact prevention as seen from the perspective of the Earth Sciences, but with an inte- grated, interdisciplinary approach. The contributions included in the book intend to give an overview of existing problems and trends and to point out certain lines along which work and/or actions will be par- ticularly needed in the near future. In short, they intend to show where we stand now with regard to those problems and in what direction we should move. Readers will find particularly useful the brief presentation of a variety of important environmental earth science top- ics, the description of the present state of the art and the suggestions for methodological approaches to solve different problems, as well as the guidelines for action presented throughout the book.

Here is a collection of papers from BIOGEOMON, The Fourth International Symposium on Ecosystem Behavior. The contributions address a wider-than-ever range of concerns: aspects of catchment monitoring and modeling; nitrogen transformations and processes; stable and radiogenic isotopes; biogeochemistry of restored ecosystems; and the dynamics of such chemicals as mercury and phosphorous, among many other topics.

Distinguished multinational contributors present research of small catchments to examine a variety of environmental problems, especially those of acidification, forest management and land-use changes. Divided into two parts, it introduces theoretical concepts followed by a review of atmospheric deposition and evaluation of weathering and erosion processes. The second half deals with the methodology of the given discipline, stressing novel approaches and discussing problems.

Regional Approaches to Water Pollution in the Environment integrates knowledge and experience on pollution problems related to industrial, agricultural and municipal activities and former military sites, with special emphasis on the Black Triangle: the region situated at the borders between North Bohemia, Polish Lower Silesia and South Saxony. Here, some five million inhabitants live in an area of brown coal basins having the highest emissions of sulphuric and nitrogen emission in the whole of Europe. The large-scale damage in this region is due to obsolete technology and insufficient equipment for monitoring emissions. Health effects are severe, and controlling the pollution can only be done at high cost. There is thus a need to exchange knowledge and experience on methods for evaluating the expected effects of measures and purification techniques to remedy ground and surface water pollution.

This Special Issue of Water, Air, and Soil Pollution offers original contributions from BIOGEOMON, The Third International Symposium on Ecosystem Behavior, which was held on the campus ofVillanova University from June 21-25, 1997. Previous meetings were held in Prague in 1987 and again in 1993. The BIOGEOMON series was initiated in 1987 when a group of researchers from the Czech Geological Survey organized a conference called GEOMON, Geochemical Monitoring in Representative Basins. GEOMON was fairly narrowly focused on monitoring of element pools and fluxes on a small watershed scale. As signalled by the change in name to BIOGEOMON, the second conference explicitly recognized that assessment of anthropogenic effects on ecosystem processes requires a combination of geochemical monitoring with other approaches, including watershed-level manipulations, use of radioactive and stable isotopic tracers, and both empirical and process modeling. The 1997 BIOGEOMON conference was the largest, with over 240 participants from 28 countries on five continents in attendance, and broadest in scope. The conference featured a plenary speaker, six keynote speakers, 35 invited speakers, over 60 oral contributed presentations, and over 75 poster presentations.