Interrelation between hydrogeomorphic and vegetative processes in rivers.

河流水文地貌和植物过程之间的相互关系。

基本信息

批准号：
11650531
负责人：
OKABE Takeshi
金额：
$ 2.18万
依托单位：
The University of Tokushima
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (C)
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

来源：
https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-11650531/
关键词：
river morphology alternate bar tidal flat river bed variation plant community colonization success sediment transport data base 河床変動計算浮遊砂濃度 GISデータベース河床変動計算法乱流モデル植生分布・動態モデル流砂量

项目摘要

1) Analysis of long-term riverbed variation : Regard to the Yoshino River, Shikoku, Japan, a data base of riverbed geometry was composed, with respect to the past 40 years. The cross-sectional shapes of individual measuring were represented by fixed 101 points. The geomorphic process was analised with the aid of empirical orthogonal function method. As a result, remarkable bed aggradation was observed and its major modes were identified.2) Vegetative and hydro-geomorphic river survey and analysis : Regarding to the Naka and Yoshino River, vegetation survey on sediment bars was were widely carried out. In addition, colonization success of riverine vegetation was observed referring to aerial photographs. Colonization traits were quantitatively related to historical hydro-geomorphic conditions of the reivers.3) Numerical reproduction of meshed vegetation maps of alternate bars : Detailed meshed vegetation maps of alternate bars formed in a downstream reach of the Yoshino River were produced by field surveys with the aid of an low aerial photography technique. A preference curve model and a neural network model were applied to judge dominant vegetation types of mesh areas from physical habitat attributes. The both models showed similar accuracy of slightly higher and lower than 70 %, however, significant difference was found in the resultant maps.4) Improvement of simulation model for riverbed variation : Mechanism of sediment suspension in flows passing vegetated areas was experimentally clarified, and its simulation model was developed. In addition, characteristics of self-formed streams and alternate bars of mixed sediment were investigated based on numerical simulation.

1）长期河床变化的分析：与过去40年相对于日本Shikoku的Yoshino河，日本Shikoku，河床几何形状的数据库。单个测量的横截面形状由固定的101点表示。地貌过程在经验正交法方法的帮助下进行了分析。结果，观察到了显着的床融化，并确定了其主要模式。2）营养和水力地球形河河的调查和分析：关于纳卡和吉诺河，对沉积物棒的植被调查进行了广泛进行。此外，观察到河流植被的殖民化成功是指航空照片。殖民特征与reivers的历史水电形态状况定量相关。3）替代条形的网状植被图的数值再现：详细的植被图：详细的在吉诺河下游河段中形成的替代条形图的网状植被图由现场演习产生，并通过辅助低空空间照片的帮助。偏好曲线模型和神经网络模型被应用于物理栖息地属性的判断网状区域的主要植被类型。两种模型均显示出相似的准确性略高和低于70％，但是，在结果的地图中发现了显着差异。4）改进河床变化的仿真模型：经过实验阐明了通过植被区域的流动区域中的沉积物悬架机理，并开发了其仿真模型。另外，根据数值模拟研究了自形流和混合沉积物的替代条的特征。