Objetivo The objective of this proposal is to develop productive and sustainable cropping syster on acid upland soils in the humid tropics. In these cropping systems the choice of practices to be used to add organic matter, whether through efficient use of crop residues or green manures (leguminous cover crops, hedgerow trees) plays a central role. A main objective of the project is to quantify both the direct crop nutrition effects of organic inputs and the contribution to long-term maintenance of soil organic matter, a criterion for sustainability. The project will be executed at two sites in Indonesia and Thailand and builds on the achievements of previous projects at those places. Through the project both sites will become a partner in the Tropical Soil Biology and Fertility (TSBF) network. Scientific objectives in the project are: quantification of the C and N balance sheets extension of a model on organic matter dynamics, assessment of the contribution of nitrogen fixation by legume cover crops and trees, quantification of N mineralization and release from plant residues in relation to the content of polyphenolics, quantification of the build-up and decomposition of soil organic matter and fractionation of soil organic matter, quantification and evaluation of the role of the microbial biomass, quantification of nitrification rates, quantification of rooting patterns of crops and trees and evaluation of the long-term C and N balance of the selected cropping systems. Three novel approaches to the study of mineralization and organic matter decomposition will be employed in this research. The first approach is the use of a new method for estimating the capacity of reactive polyphenols to bind protein which appears to be a very sensitive indicator of the initial nitrogen mineralization rate. The second approach is the dual use of l5N labelling together with natural l3C enrichments to estimate the rates of decomposition of mixed organic residues. The third approach is a new density fractionation of soil organic matter in recent inputs, an intermediate fraction and relatively stable soil organic matter. The methods will provide new information on the process of nitrogen release in soils which is critical in determining the efficiency of nitrogen utilization within the cropping system. New management strategies will be explored and evaluated. The experimental wor will be linked with an extensive Farming Systems Research. A network of farmer-led research trials will be established to develop and adapt promising technologies for organic matter management arising from the research through a reiterative process of experimentation and modification of ideas. Ámbito científico natural sciencesbiological sciencesbiochemistrybiomoleculesproteinssocial sciencessociologydemographyfertilitymedical and health scienceshealth sciencesnutritionagricultural sciencesagricultural biotechnologybiomassagricultural sciencesagriculture, forestry, and fisheriesagriculturegrains and oilseedslegumes Programa(s) FP3-STD 3 - Specific research and technological development programme (EEC) in the field of the life sciences and technologies for developing countries, 1990-1994 Tema(s) Data not available Convocatoria de propuestas Data not available Régimen de financiación CSC - Cost-sharing contracts Coordinador Dienst Landbouwkundig Onderzoek Aportación de la UE Sin datos Dirección 92,Oosterweg 9750 RA Haren Países Bajos Ver en el mapa Coste total Sin datos Participantes (3) Ordenar alfabéticamente Ordenar por aportación de la UE Ampliar todo Contraer todo Khon Kaen University Tailandia Aportación de la UE Sin datos Dirección 40002 Khon Kaen Ver en el mapa Coste total Sin datos UNIVERSITY OF BRAWIJAYA Indonesia Aportación de la UE Sin datos Dirección Jalan Veteran Malang, East Java 65145 MALANG Ver en el mapa Coste total Sin datos WYE COLLEGE Reino Unido Aportación de la UE Sin datos Dirección University of London TN25 5AH Ashford Ver en el mapa Coste total Sin datos
