摘要
为研究北江飞来峡水库社岗流域内水土流失特性,采用MIKE21平台模拟分析降雨、植被因素对流域水动力学与水沙演变特征影响。研究得到泥沙淤积厚度与降雨强度为正相关关系,但降雨强度愈大,不仅淤积厚度峰、谷值发生变化,且淤积厚度增幅也减小,受运营期时序增长效应影响,中等降雨强度下更为敏感。每阶次植被NDVI0.06的变化,运营100d时断面淤积厚度平均降幅为12.5%;1500m~1800m、1090m~1500m区间断面水动力特征受运营时序效应最为敏感。降雨150mm/d的阶次增长,断面平均含沙量增幅为13.2%,但降雨强度增大到一定界限,会改变河道上下游泥沙迁移、悬浮特征。植被NDVI值愈大,则河道含沙量愈低,且NDVI参数值对断面含沙量影响具有恒定性。结果可为研究河道固土护沙及水土保持提供参考。
In order to study the characteristics of soil and water loss in the Shegang watershed of Feilaixia Reservoir,the MIKE21 platform was used to simulate and analyze the influence of rainfall and vegetation factors on the hydrodynamics and evolution of water and sediment in the watershed.The study shows that the sediment deposition thickness is positively correlated with the rainfall intensity,but the greater the rainfall intensity,not only the peak and valley values of the deposition thickness change,but also the increase in the deposition thickness decreases.Affected by the effect of time series growth during the operation period,it is more sensitive under moderate rainfall intensity.The variation of vegetation NDVI0.06 in each order has an average reduction of 12.5%in the section deposition thickness when the operation is 100 days.The hydrodynamic characteristics of the section in the 1500 m~1800 m and 1090 m~1500 m intervals are most sensitive to the operation sequence effect.When the order of rainfall increases by 150 mm/d,the average sediment content of the section increases by 13.2%,but the rainfall intensity increases to a certain limit,which will change the characteristics of sediment migration and suspension in the upstream and downstream of the river.The larger the vegetation NDVI value,the lower the sediment content of the river channel,and the NDVI parameter value has a constant effect on the section sediment content.The results can provide a reference for the study of soil consolidation and sand protection and soil and water conservation in riverchannels.
作者
宋加平
欧阳高明
李灿
Song Jiaping;Ouyang Gaoming;Li Can(Guangdong Zhonghao Survey and Design Consulting Co.,Ltd.,Zhaoqing 526060,Guangdong)
出处
《陕西水利》
2022年第12期11-14,共4页
Shaanxi Water Resources
关键词
MIKE21
水动力学
水沙演变
流域
MIKE21
hydrodynamics
water and sediment evolution
watershed
