权益分类	功能权益	普通用户	{{item.name}}会员
{{category.name}}	{{benefitItem.name}}

The river improvement effects on endangered freshwater fishes and plants of the upper reach of The Muko-River, Hyogo Prefecture, Japan.

河流改善对日本兵库县向河上游濒危淡水鱼类和植物的影响。

基本信息

批准号：
19510093
负责人：
TANAKA Tetsuo
金额：
$ 2.91万
依托单位：
University of Hyogo
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (C)
财政年份：
2007
资助国家：
日本
起止时间：
2007 至 2009
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-19510093/
关键词：
河川改修希少淡水魚治水

项目摘要

Upper reach of the Muko-River is high-biodiversity reach inhabited by many species of endangered freshwater plants and animals. This point is characterized by low altitude and low gradient of stream bed, so this area show tendency of sandy-mad accumulation on stream bed like as lower reach of other streams. In the same time, this stream character arise frequent flood caused by high deposition rate of sandy-mad. The Hyogo Prefecture river section began the river improvement that centered on the soil excavation of the riverbed and the riverside in the Muko-River upstream region to achieve the flood control target of 1/2 probabilities in 2003.A physical impact by this river improvement aims at the influence given to a endangered freshwater fish that lives in this area and it has aimed to understand the influence of the river improvement by monitoring a long term, and to present the reduction plan of the influence in addition. After 2003 doing the test excavation in the first, the fish cro … More wd to this change is continuously analyzing the investigation how it reacts until 2009 as the transition of a physical, environmental condition such as depth and the bottom sediments in the standard investigation section.The width of the river channel, depth, and the flow velocity distribution are made monotonous by digging, an especially deep point disappears, and the area of the mud bottom has reduced. These habitat elements have not returned completely at point that eight years passed after it digs up the examination. White and brown bitterling, Acheilognathus tabira and Tnanakia limbata, having misgivings for fishes captured by the trap net corresponding to this, especially keep decreasing capture number from 2005 continuing to 2009 though it increased once why in 2003/2004.In this river improvement, if the river channel section made to flow as the water level of planned high water was safe was able to be secured, the deep pool and the meander reach that set up the obstacle in the river channel. Local deep pool, the revival of the shelter that accompanies it, and the reproduction of the sedimentary environment are expected centering on the meander point and the obstacle it. However, an original state of habitat-mosaic to bring up various aquatic animals and plants might not be created again in this river improvement method making the constant river bed gradients by such a long distance. Less

木科河上游是生物多样性很高的地区，居住着许多濒危淡水动植物物种。该地区海拔低、河床坡度低，与其他河流下游一样，呈现出河床沙尘淤积的趋势。同时，由于砂岩沉积速率较高，这种河流特性导致洪水频繁发生。2003年，兵库县河段开始对目可河上游河床和河岸进行以挖土为中心的河道整治，以实现1/2概率的防洪目标。此次河道整治的物理影响是针对该地区一种濒危淡水鱼的影响，旨在通过长期监测了解河流整治的影响，并提出减少影响的方案。在2003年进行了第一次试掘后，鱼十字架…对于这一变化，更多的是不断分析调查情况，直到2009年，随着深度和标准调查断面底质等物理、环境条件的过渡，调查如何反应。通过挖掘，使河道宽度、深度和流速分布单调，特别深的点消失，泥底面积减少。经过八年的挖掘，这些栖息地元素还没有完全恢复。由于对与此相对应的网捕鱼类有所顾虑，特别是从2005年到2009年，捕捞数量一直在减少，2003/2004年却一度增加。在这次河道整治中，如果能够保证河段在计划高水位安全的情况下流动，那么在河床上设置障碍的深池和曲流河段就能得到保证。以曲流点和障碍为中心的局部深水池、与之相伴的避难所的复兴和沉积环境的再现是可望实现的。然而，在这种河流改良方法中，可能不会再创造出栖息地镶嵌以培育各种水生动植物的原始状态，使恒定的河床坡度保持这么远的距离。较少