Objetivo The objective is to strengthen the scientific knowledge about functional properties of brown dissolved organic matter (humic substances (HS)) in surface waters which can influence the acidification of softwater ecosystems and its reversibility, and can alter the impact of acidification on aquatic organisms. Specifically this project will address the questions to which extent humic substances: contribute directly to acidification; interact with other dissolved materials; and directly influence aquatic biota. The research will cover investigations on acidification processes, the effects of acid precipitation on soil minerals and soil organic matter as well as on the amounts of deliberated solutes from catchment soils into the surface waters. The role of HS in the acidification processes of aquatic ecosystems and its effect on aquatic biota will be studied through a large scale field experiment with whole catchment manipulation. In this international experiment, called HUMEX project, one half of a dystrophic lake and the corresponding catchment will be artificially acidified with water from a nearby lake (naturally low in salts and organic matter). The lake is divided by a water tight curtain from the other half which is serving as the unacidified control. Detailed studies will include : soil water in the catchment; surface and groundwater entering into the lake; chemical composition of lake water and of outflow water in particular regarding HS in the water column and in sediments; microbial decomposition of detritus, nutrient (phosphorous and iron) availability in dystrophic water in relation to acidification and HS; and impacts on bacterial, phytoplankton, zooplankton, macroinvertebrate, macrovegetation and fish communities. Ámbito científico natural sciencesbiological sciencesecologyecosystemsnatural sciencesearth and related environmental scienceshydrologylimnology Programa(s) FP2-STEP - Two specific research and technological development programmes (EEC) in the field of the environment STEP/EPOCH - STEP -, 1989-1992 Tema(s) Data not available Convocatoria de propuestas Data not available Régimen de financiación CSC - Cost-sharing contracts Coordinador ROYAL NETHERLANDS ACADEMY OF ARTS AND SCIENCE Aportación de la UE Sin datos Dirección 6,Rijksstraatweg 6 3631 AC NIEUWERSLUIS Países Bajos Ver en el mapa Coste total Sin datos Participantes (6) Ordenar alfabéticamente Ordenar por aportación de la UE Ampliar todo Contraer todo Consejo Superior de Investigaciones Cientòficas España Aportación de la UE Sin datos Dirección 18-26,Jordi Girona 08034 Barcelona Ver en el mapa Coste total Sin datos Lunds Universitet Suecia Aportación de la UE Sin datos Dirección 221 00 Lund Ver en el mapa Coste total Sin datos Max-Planck-Gesellschaft zur Förderung der Wissenschaften eV Alemania Aportación de la UE Sin datos Dirección August-Thienemann-Straße 2 24306 Plön Ver en el mapa Coste total Sin datos NORWEGIAN INSTITUTE FOR WATER RESEARCH Noruega Aportación de la UE Sin datos Dirección 19,Brekkeveien 19 0411 Oslo Ver en el mapa Enlaces Sitio web Opens in new window Coste total Sin datos UNIVERSITY OF HELSINKI Finlandia Aportación de la UE Sin datos Dirección 320,Paeaejaerventie 320 16900 LAMMI Ver en el mapa Coste total Sin datos UNIVERSITY OF LANCASTER Reino Unido Aportación de la UE Sin datos Dirección Bailrigg LA1 4YQ LANCASTER /HIGH BANTHAM Ver en el mapa Coste total Sin datos