漓江上游典型森林植被对降水径流的调节作用

Abstract

PDF HTML阅读 XML下载 导出引用 引用提醒 漓江上游典型森林植被对降水径流的调节作用 DOI: 10.5846/stxb201311262814 作者: 作者单位: 桂林理工大学旅游学院 广西 桂林,桂林理工大学旅游学院 广西 桂林,桂林理工大学旅游学院 广西 桂林,桂林理工大学,广西猫儿山国家级自然保护区管理局 广西 兴安,广西猫儿山国家级自然保护区管理局 广西 兴安 作者简介: 通讯作者: 中图分类号: 基金项目: 国家自然科学基金项目(30860058, 41261006);国家科技支撑计划课题(2012BAC16B04);广西科技攻关计划课题(桂科攻1298006-3) The regulation effect of typical forest on rainfall-runoff in upper reaches of Lijiang River Author: Affiliation: Guilin University of technology,Guilin university of technology,Guilin university of technology,,, Fund Project: 摘要 | 图/表 | 访问统计 | 参考文献 | 相似文献 | 引证文献 | 资源附件 | 文章评论 摘要:利用野外同步长期定位观测林外降雨、地表径流和河川径流的方法,对漓江上游典型森林植被的生态水文过程进行观测研究。结果表明:1)流域降水年内分配极不均匀,50a年降雨量总体变化趋势不明显。林冠截留受林外降雨特征的影响,也与植被类型密切相关。2)地表径流平均滞后时间为70 min。在连续降雨的情况下,降雨滞后效应不再明显,甚至出现地表径流与降雨同步的现象,小降雨可能产生大的地表径流,从而加大流域在雨季发生洪灾的风险。3)湿季径流系数略大于旱季,干季降水量减少,且森林植被消耗大量水分,减少了枯水期径流的产生,增大发生旱灾的风险。森林植被延长河川径流持续时间,使一次持续18 d的降水过程形成的径流,在降水停止后能延续24 d。降雨后退水持续时间与前期降水及后期降水叠加有关。目的为揭示漓江上游森林植被对降水径流的调节作用,客观评估漓江上游水资源潜力、加强流域水资源管理和森林经营提供科学依据。 Abstract:The relationship between forest and water resources has been a main scientific issue in the study of ecological hydrology, which is also an important theoretic foundation for hydrological prediction and regulation. Different forest vegetations create different canopy structure and micro-environment, which affect the distribution of rainfall among canopy, litter and different soil layers through water interception, water retention and transpiration and exert a great impact on surface runoff and river discharge. Recent studies have showed that the function of forest vegetation in reducing flood peaks during the rainy season and increasing the river flow in the dry season might be exaggerated. The relationship between forest vegetation and river flow still needs further confirmation. Lijiang River was a core mountain-water scenic spot in Guilin. Precipitation in Lijiang river basin was abundant, but its distribution within the year was irregular and rainfall mainly happened in rainy season (from March to August). Forest vegetation in the basin plays an important ecological and hydrological regulating function. In this research, data was collected in typical forest vegetation in upper reaches of Lijiang River in Mao'er Mountain National Nature Reserve, Guangxi Province. Hydrological processes, such as rainfall, surface runoff and river flow were monitored and analyzed in typical forests of Mao'er Mountain. The results showed that, 1)The distribution of annual and inter-annual precipitation was irregular revealed by statistical analysis of annual precipitation. The rainfall intensity and the rainfall frequency in the rainy season were heavy and the rainfall in the dry season (from September to February of the following year) accounts for only 17.61% of the annual total precipitation.No significant trend was found for inter-annual precipitation in the last 50 years. The canopy interception was greatly related with rainfall characteristics and forest vegetation. 2)Forest ecosystems had complex canopy structure and exerted a great impact on rainfall redistribution and the average lag time of surface runoff was 70 min. With continuous rainfall, the lagging effect might not be obvious and the surface runoff and the rainfall appeared at the same time, which largely increased the probability of generating heavy runoff after light rain and also the risk of flood in rainy season. 3)The runoff coefficient in dry season was lower than that in rainy season because of less rainfall and more evapo-transpiration, which increased the risk of serious drought. Forest vegetation put off the peak of river flow behind, extended the runoff duration for 24 days with 18 days of continuous rainfall. For a long time, due to the different geographical environment, soil conditions and forest structure has different influence on the redistribution of precipitation, the formation process of surface runoff, underground runoff as well as evaporation, which lead to the relationships of forest vegetation, surface runoff, and river flow are still controversial in the academia. This study would provide scientific basis for better understanding of the relationships between forest vegetation and its hydrological effects, helping to facilitate water resources and achieving wise forest management in upper reaches of Lijiang River. 参考文献 相似文献 引证文献