中国水土保持科学2017,Vol.15Issue(3):1-8,8.DOI:10.16843/j.sswc.2017.03.001
红黏土侵蚀劣地集水区30年植被恢复中的水沙特征
Characteristics of runoff and sediment yield of catchment area under 30 years vegetation restoration in red clay erosion badland
摘要
Abstract
[Background]The red soil region is one of the typical areas suffering serious soil erosion in southern China.The red clay badland is a kind of seriously eroded degradation and is still one of the main obstacle factors in enhancing regional soil quality and ecosystem function.Thus,suitable management is urgently needed,and systematic analysis and evaluation should be carried out.This paper is therefore conducted to evaluate the soil and water conservation benefit of the vegetation restoration measures in red clay badland.[Methods] Two field plots were built according to the natural drainage boundary 30 years ago.One is in the bare land as control and the other is vegetation restoration treatment.Runoff and sediment generation were monitored continuously under the natural rainfall condition.According to the long-term field plot monitoring data and rainfall event process information,the dynamic of runoff and sediment yield can be quantitatively described and the benefits of vegetation restoration can be evaluated.[Results] 1) The runoff yield showed significant differences between the bare land and vegetation treatment at the 6th year of restoration.Sediment yield was approximately zero in the vegetation recovered plot after 8 years.The dynamic characteristics of both runoff and sediment yield throughout a year followed the same trend as rainfall,concentrating from April to June.The efficiencies for vegetation restoration in reducing runoff and soil loss were more than 40% and 90% respectively.The vegetation significantly reduced the coefficients of regression curves,meaning that the runoff and sediment yield in the restored land tended to be less than that of the bare land with the same precipitation.2) The dynamic of the runoff and sediment yield during a rainfall event process showed multi peak curves and consistent with the trend of the rainfall intensity (I60max).The time to runoff and sediment yield in the vegetation treatment generally 1 hour delayed compared with the bare land.Meanwhile,the peak runoff and sediment in the restored land were also delayed and decreased by 67%-83%.The benefit of vegetation on reducing peak value of the runoff under moderate rain was better than that under rainstorm or heavy rain.3) Comparing with the bare land,the loss of total nitrogen (TN),total phosphorus (TP) and total potassium (TK) in the restored land were reduced by 54.62%,57.53%,and 56.46% respectively.During a rainfall and runoff process,the total losses of TP were obviously lower than the TN and TK.The concentration of TN and TK in rainfall process fluctuated and was higher than TP which was relatively stable.[Conclusions] The rapid restoration of vegetation can effectively control the surface runoff and sediment yield,delay runoff generation process and reduce peak flow.Meanwhile,recovery measures can significantly reduce nutrient loss in runoff and sediment.Therefore the vegetation restoration can be applied in local ecology recover and soil management.This study can provide a scientific basis for the assessment of the water and soil conservation benefit of vegetation restoration in red clay badland.关键词
红黏土区/植被恢复/水土流失/降雨过程/养分流失Key words
red clay area/vegetation restoration/soil and water losses/rainfall event process/nutrient loss分类
农业科技引用本文复制引用
顾亚兰,梁音,曹龙熹,卢慧中,张玉刚..红黏土侵蚀劣地集水区30年植被恢复中的水沙特征[J].中国水土保持科学,2017,15(3):1-8,8.基金项目
国家科技支撑计划“大型崩岗的农业综合开发技术与示范”(2014BAD15B0302) (2014BAD15B0302)
国家自然科学基金“红壤丘陵区小流域路网的水沙效应作用机理与模拟”(41571273) (41571273)
江苏省自然科学基金“基于GIS的流域坡长因子自动计算方法研究”(BK2015610) (BK2015610)