长江源区1980—2020 年水沙变化规律
基于长江源区1980—2020年12个站点日降水及直门达站年径流及泥沙等数据,利用中国土壤流失方程、偏最小二乘结构方程和累积距平等方法,分析源区土壤侵蚀、河道水沙变化及长时间尺度下与降水的耦合作用机制。结果表明:(1)长江源区年土壤侵蚀模数呈显著增加趋势(P<0.05),且年均土壤侵蚀模数为4.71 t·hm-2·a-1,强烈及以上强度侵蚀主要分布在源区东南部。(2)源区径流量显著增加(P<0.05),且2004年为突变年,含沙量和输沙量无明显变化趋势。(3)降水对径流和土壤侵蚀均有显著正向效应,解释度分别为70%、52.9%。径流和土壤侵蚀对输沙量变化均具有直接正向影响,降水、径流和土壤侵蚀对输沙量变化的综合解释度达72.5%,结果可为流域生态工程实施效果的研究与评价提供科学依据。
bstractThe changes in soil loss, runoff, and sediment load in the headwaters of the Yangtze River and their correlation were studied based on the data of daily precipitation at 12 stations, and annual runoff and sediment at Zhimenda station in the headwaters of this river from 1980 to 2020. (1) The annual soil erosion modulus in the source area showed a significantly increasing trend (P<0.05), and the average annual soil erosion modulus was 4.71 t·hm-2·a-1. The erosion intensity and higher grades of erosion were mainly distributed in the southeast of the headwaters of the Yangtze River. (2) The runoff increased significantly (P<0.05), however, there was an abrupt change in 2004 when the suspended sediment concentrate and sediment load showed no significant change. (3) Precipitation had a significant positive effect on runoff and soil loss at 70% and 52.9%, respectively. Both runoff and soil loss showed direct positive effects on the sediment load. Precipitation, runoff, and soil loss explained 72.5% of the variation in sediment load. During this period, changes in precipitation had significant effects on soil loss and sediment in the headwaters of the Yangtze River. The results can provide a scientific basis for the research and evaluation of the effects of implementing ecological engineering in the headwaters of the Yangtze River.
刘 竞、刘洪鹄、姚春艳
水利调查、水利规划环境科学理论灾害、灾害防治
中国土壤流失方程结构方程模型气候变化土壤侵蚀
刘 竞,刘洪鹄,姚春艳.长江源区1980—2020 年水沙变化规律[EB/OL].(2023-05-30)[2025-08-02].https://chinaxiv.org/abs/202305.00252.点此复制
评论