文献类型： 会议论文

第一作者： Erik Steen Jensen

作者： Erik Steen Jensen ¹ ; Henrik Hauggaard-Nielsen;

作者机构： 1.Organic Farming Unit, Department of Agricultural Sciences, The Royal Veterinary and Agricultural University, DK-2630 Taastrup, Denmark

关键词： biological diversity;biological nitrogen fixation;fertilizer N;gaseous N losses;leaching of nitrate;nitrogen cycling;soil fertility

会议名称： Maximising the use of biological nitrogen fixation in agriculture :

主办单位：

页码： 177-186

摘要： Asymbiotic, associative or symbiotic biological N_2 fixation (BNF), is a free and renewable resource, which should constitute an integral part of sustainable agro-ecosystems. Yet there has been a rapid increase in use of fertiliser N and a paralleldecline in the cultivation of leguminous plants and BNF, especially in the developed world. Fertilisers have boosted crop yields, but intensive agricultural systems have increasingly negative effects on the atmospheric and aquatic environments. BNF, either alone or in combination with fertilisers and animal manures, may prove to be a better solution to supply nitrogen to the cropping systems of the future. This review focuses on the potential benefit of BNF on the environment especially on soil acidification, rhizosphere processes and plant CO_2 fixation. As fertiliser N has supplanted BNF in agriculture the re-substitution of BNF is considered. What is the consequence of fertiliser N production on energy use? The effect of fertiliser use on the release of the greenhouse gas CO_2 is estimated at approximately 1 percent of the global anthropogenic emission of CO_2. The role of BNF on nitrogen cycling, ammonia volatilisation, N_2O emission and NO_3 leaching suggests that BNF is less likely than fertilisers to cause losses during pre-cropping and cropping. Sometimes however the post-harvest losses may be greater, due to the special qualities of legume residues. Nevertheless, legumes provide other 'ecological services' including improved soil structure,erosion protection and greater biological diversity.

分类号： S14