Evaluation of Nitrogen Cycling in a Basin Associated with Forest, Grassland and Animal Husbandry, Hokkaido, Japan

日本北海道与森林、草原和畜牧业相关的盆地的氮循环评估

基本信息

批准号：
11460028
负责人：
HATANO Ryusuke
金额：
$ 9.6万
依托单位：
HOKKAIDO UNIVERSITY
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (B)
财政年份：
1999
资助国家：
日本
起止时间：
1999 至 2001
项目状态：
已结题

项目摘要

Expansion of N cycling in ecosystems with increase of human activity impacts on not only regional environments but also global environments. Global warming with increasing emission of N2O, acidification with increasing of NH3 deposition, water pollution with NO3 leaching, degradation of bio-diversity with N load are the problems associated with N cycling in ecosystems. This report discussed about optimum N cycling in agro-forested ecosystems. In order to evaluate optimum amount of N cycling in agro-forested ecosystems, we studied following topics: 1) Impact of N cycling in basin ecosystem complexes on stream water quality; 2) Impact of atmospheric N deposition on forest soil ecosystems; 3) Green house effect gas fluxes in basin ecosystem complexes. Surplus N in agricultural lands and disposal N in regions are major factor determining stream water quality. N flow model was crucial for their evaluation. Unique N load was shown in each land use structure in a basin ecosystem complex. Most … More N load occurred during rainfall and snow melt season. In agricultural land, chemical fertilizer N, which was supplied to the fields within a 10-day before rain, was mainly discharged to the stream. Although animal and human excreta produced with the consumption of feed and food can be used as manure, inadequate composting process resulted in water pollution. Ammonium volatilization induced acidification of forest soils and stream N discharge induces eutrophication of coastal ecosystems. However they depended on soil quality. Acidification was controlled by exchangeable Ca in soils and eutrophication was controlled by Si supply from soils. Soil forming process, which releases both Ca and Si from primary rock minerals to soil solution, was quite important factor for occurrence of both acidification and eutropication. Hokkaido was the specific area in the world for occurrence of large N2O emission from agricultural fields. Denitrification was major process for large N2O emission. Conversion of forested land to crop land increased global warming effect of the land. However, N2O emission through water discharge from agricultural fields was smaller than the values reported previously. According to the above results, it is necessary for us to evaluate optimal N cycling with scenario analysis using N cycling model to describe numerically N flow associated with production and consumption of food and feed in basin ecosystem complex. Less

随着人类活动的影响不仅对区域环境，而且对全球环境的影响增加，在生态系统中的N自行车扩展。随着N2O排放的增加，随着NH3沉积的增加，NO3步行的水污染，随着n负载的生物多样性降解，酸化是与生态系统中N循环有关的问题。该报告讨论了有关农业森林生态系统中最佳n循环。为了评估农业森林生态系统中最佳的N循环量，我们研究了以下主题：1）N循环在盆地生态系统复合物中对溪流水质的影响； 2）大气n沉积对森林土壤生态系统的影响； 3）盆地生态系统络合物中的温室影响气体通量。在农业用地和处置n中的盈余N是决定溪流质量的主要因素。 n流模型对于他们的评估至关重要。在盆地生态系统络合物中的每个土地使用结构中显示了唯一的N负载。大多数…更多的N负载发生在降雨和降雪季节期间。在农业土地上，在雨前的10天内向田野提供的化肥N主要被排放到溪流中。尽管食用饲料和食物产生的动物和人类极端可以用作手动，但堆肥过程不足导致水污染。铵挥发诱导的森林土壤和河流排放诱导了沿海生态系统的富营养化。但是它们取决于土壤质量。通过土壤中可交换的CA控制酸化，并通过土壤的SI供应来控制富营养化。土壤形成过程将Ca和Si从原发性岩石矿物到土壤溶液中释放，是发生酸化和富营养化的重要因素。北海道（Hokkaido）是世界上特定地区，该领域是从农田中出现大型N2O发射的地区。反硝化是大型N2O排放的主要过程。将森林土地转换为作物土地增加了土地的全球变暖效应。然而，通过从农田排出的水排放的N2O发射小于先前报告的值。根据上述结果，我们必须使用N循环模型来评估最佳的N循环，以描述与盆地生态系统复合物中食物和饲料的基本上n流相关的N流。较少的