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Evaluation of effects of environmental degradation on natural mass cycles

环境退化对自然质量循环影响的评估

基本信息

批准号：
13308030
负责人：
FUKUOKA Masato
金额：
$ 10.9万
依托单位：
Hiroshima University
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (A)
财政年份：
2001
资助国家：
日本
起止时间：
2001 至 2003
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-13308030/
关键词：
mass balance flux environmental degradation rock water biology acidification weathering

项目摘要

For sustainable use of Seto Inland Sea and coastal catchments, we confirmed natural mass cycle flux and soil degradation rate and evaluate the variation of mass cycle with environmental change, such as acid rain, global warming, forest fire, artificial impact.Our conclusions are summarize as follows,1. We quantified various flux in mass cycle of catchments evapotranspiration rate, infiltration rate, river discharge, groundwater flow, vegetation growing rate, weathering rate, erosion rate. Consequently, soil degradation trend was confirmed in forest fire catchments for initial two years. Erosion rate in forest fire catchments became more than 30 times of that in forest.2. We conducted the scale up the weathering process and rate in micro view and short term scales. The weathering rate in micro scale was higher than that in catchment scale. This was solved by heterogeneity of weathering process such as micro sheeting joints and fissure, thermal water effect, groundwater slow in long term. Furthermore, both of biochemical process and rainfall as the unstable condition had significant role on that.3. We evaluated the transport of anthropogenic input mass ; trace metal of atmosphere fall and nitrate of agricultural input and living waste. Trace metal was released from soil with acidification and discharged in dissolved form in the source area. On the other hand, it was transported with suspension in down stream due to adsorption. Nitrate discharged through the river to sea. But the content decreased by some purification process such as denitrification in groundwater and river bed.

为了实现内陆海和沿海流域的可持续利用，我们确定了自然质量循环通量和土壤退化速率，并评价了自然质量循环通量和土壤退化速率随环境变化的变化，如酸雨、全球变暖、森林火灾、人为影响等。主要结论如下：1.量化了流域蒸散速率、入渗速率、河流流量、地下水流量、植被生长速率、风化速率、侵蚀速率等质量周期的各种通量。因此，森林火灾集水区头两年的土壤退化趋势得到了证实。林火集水区的侵蚀速率是森林的30倍以上。我们从微观和短期尺度上对风化过程和风化速率进行了放大。微尺度上的风化速率高于集水区尺度上的风化速率。这主要是由于微片状节理裂隙、热水作用、地下水长期缓流等风化作用的非均质性所造成的。此外，生化过程和降雨量作为不稳定条件都对此有显著影响。评价了人为输入物质、大气中痕量金属、农业投入物和生活垃圾中的硝酸盐的迁移情况。痕量金属随酸化作用从土壤中释放出来，并以溶解形式排放到源区。另一方面，由于吸附作用，悬浮物在下游以悬浮形式输送。硝酸盐通过这条河排入大海。但经过地下水、河床反硝化等净化处理后，其含量有所下降。