Field observation on integrated sediment management in Brantas river basin, Indonesia

印度尼西亚布兰塔斯河流域泥沙综合管理现场观察

基本信息

批准号：
15404017
负责人：
FUJITA Masaharu
金额：
$ 5.25万
依托单位：
KYOTO UNIVERSITY
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (B)
财政年份：
2003
资助国家：
日本
起止时间：
2003 至 2005
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-15404017/
关键词：
Brantas River Integrated sediment management Sediment routine system in river basin Sediment production Bed variation Volcanic eruption Rainfall runoff Sediment runoff 土砂管理侵食インドネシア

项目摘要

The information available to the integrated sediment management of the Brantas river basin was examined by the field survey, field observation, and the simulation of bed variation. Particularly we investigated the topographical change of the main river after the eruption of Mt.Kelude in 1994 and the sediment yield and transport in M.Semeru basin considering the influence of sand mining and deforestation as human impact. Immediately after the eruption in 1994, a large amount of sediment flowed into the main river rapidly from the tributaries and a sever bed aggradation took place and the bed material became much finer. The sediment discharge from the tributaries immediately after the eruption is an essential information for the sediment management. As a result of the analysis, it was found that the condition is evaluated with the local hydraulic condition and the grain size distribution of the produced sediment. After the eruption, however, the tendency of bed variation changed quickly to the opposite. According to our survey, we can recognize the sediment movement in the tributaries even in rainy season and sand mining was very active in the main river and the tributaries. It is seemed that sand mining and irrigation cause the decrease in sediment supply and water discharge and consequently the bed level became much lower and the bed surface was covered by armor coat in the main river and tributaries. Field observation on suspended load in the main river has indicated the sediment yield of fine sediment was decreasing gradually after the eruption, but it has recently increased again. One of the reasons is the deforestation and more active sand mining. Also, field survey in Lesti river has indicated the suspended load concentration is very large in early stages of the rainy season because the farmland is disturbed by cultivation.

通过现场调查，现场观察和床变异的模拟，检查了Brantas河流盆地集成沉积物管理的信息。特别是我们研究了1994年凯鲁德山（Mt.kelude）爆发后，主要河流的地形变化，并考虑到挖矿和森林砍伐的影响，塞米鲁盆地的沉积物产量和运输是人类的影响。 1994年爆发后，立即从支流中迅速流入主要河流，并发生了严重的床，床材料变得更加细腻。喷发后立即从支流排出的沉积物是沉积物管理的重要信息。分析的结果是，发现条件是通过局部液压条件和产生沉积物的晶粒尺寸分布进行评估的。然而，在喷发后，床变异的趋势迅速变为相反。根据我们的调查，即使在雨季，我们也可以认识到支流中的沉积物运动，而在主河和支流中，砂矿开采也非常活跃。看来沙采矿和灌溉会导致沉积物供应和水排放的减少，因此床位变得更低，床表面被主要河流和支流的装甲外套覆盖。主要河流中悬浮负荷上的现场观察表明，喷发后的沉积物的沉积物产量正在逐渐减少，但最近又增加了。原因之一是森林砍伐和更活跃的砂矿。此外，利斯蒂河（Lesti River）的现场调查表明，由于农田受到耕种的干扰，在雨季的早期阶段，悬浮的负荷浓度非常大。