香根草植物篱对三峡库区坡地紫色土侵蚀的影响  

Effects of Vetiveria zizanioides hedgerow on the erosion of purple soil of slope land in the Three Gorges Reservoir Area of China

作　　者：郭萍[1] 夏振尧[1,2] 高峰 胡欢 张千恒 杨悦舒[1,2] 肖海 Guo Ping;Xia Zhenyao;Gao Feng;Hu Huan;Zhang Qianheng;Yang Yueshu;Xiao Hai(Key Laboratory of Geological Hazards on Three Gorges Reservoir Area(China Three Gorges University),Ministry of Education,Yichang 443002,China;Engineering Research Center of Eco-environment in Three Gorges Reservoir Region,Ministry of Education,China Three Gorges University,Yichang 443002,China)

机构地区：[1]三峡库区地质灾害教育部重点实验室(三峡大学),宜昌443002 [2]三峡库区生态环境教育部工程研究中心,宜昌443002

出　　处：《农业工程学报》2021年第19期105-112,共8页Transactions of the Chinese Society of Agricultural Engineering

基　　金：国家自然科学基金(41807068;U2040207);三峡大学优秀博士论文基金(2020BSPY003)。

摘　　要：紫色土坡地是三峡库区水土流失的主要来源,严重影响着三峡工程的运行安全。植物篱是三峡库区坡地的重要水土保持措施之一,具有明显的减流减沙效益,然而植物篱地上及地下部分对坡面侵蚀的影响尚不明确。为此,该研究通过设置2个坡度(15°和25°)、2个降雨强度(60和120mm/h)和3个坡面条件(裸坡对照、植物篱和仅有植物篱根系),开展人工降雨试验,分析各试验条件下初始产流时间、径流量和侵蚀量的变化特征。结果表明:植物篱、地下部分和地上部分的平均减沙效益分别为75.59%、29.45%、46.13%,是对应的平均减流效益的4.79、4.60、4.92倍;地上部分和地下部分延缓初始产流时间、减流和减沙平均贡献率分别为48.28%和51.72%、62.25%和37.75%、60.44%和39.56%,表明植物篱对减沙作用更明显,且地上部分对产流产沙的影响大于其地下部分。以上结果加深了香根草植物篱对坡地侵蚀过程影响的理解,可为三峡库区紫色土坡地水土流失防治提供科学依据。Purple soil erosion of slope land has posed a serious threat to the operation safety of the Three Gorges Project in recent years. Fortunately, the hedgerow has widely been one of the most important measures for soil and water conservation on slope land. Most studies have also demonstrated that the hedgerows can effectively reduce the runoff and sediment of the slope.However, the specific reduction was still lacking on the aboveground and underground part of hedgerows. Taking the purple soil of slope land in the Three Gorges Reservoir Area as the research object, this study aims to clarify the effects of Vetiveriazizanioides L. hedgerow on the erosion of purple soil. Simulated rainfall experiments were also conducted at 2 slope gradients(15° and 25°), 2 rainfall intensities(60 and 120 mm/h), and 3 slope conditions(CK-Control check, P-Hedgerow, and R-Only hedgerow roots). The specific characteristics were analyzed for the initial runoff time, runoff, and sediment with rainfall duration under different slope conditions. The results indicated that the average contribution rates were 48.28% and 51.72% of the aboveground and underground parts to the increase of initial runoff time, respectively. The runoff production showed a trend of first increasing and then fluctuating, finally stable under different rainfall intensity and slope conditions. In sediment yield, the erosion rate of slope always kept a fluctuating and stable trend under the condition of P slope, whereas,there was a slow increase at first and a rapid increase under the condition of CK and R slope. The runoff reduction efficiency of hedgerows ranged from 11.20% to 26.19%, while the sediment reduction efficiency of hedgerows ranged from 71.54% to 83.63%. The average benefits of sediment reduction, underground and aboveground parts were 75.59%, 29.45%, and 46.13%,respectively, which were 4.79, 4.60, and 4.92 times of the average. The average contribution rates were 62.25% and 37.75%for the aboveground and underground part of hedgerows to the runoff reduct

关 键 词：土壤 侵蚀 植物篱 三峡库区 地上部分 地下部分 减流减沙效益 

分 类 号：S157.2[农业科学—土壤学]