退耕还林(草)背景下榆林市土壤侵蚀变化与未来趋势预测  

Change analysis and future prediction of soil erosion in Yulin in the context of Grain for Green Project

作　　者：杨波 王全九[2] 周佩 许晓婷 党江茹 YANG Bo;WANG Quanjiu;ZHOU Pei;XU Xiaoting;DANG Jiangru(Institute of Natural Resources Environment and Historical Culture of Xianyang Normal University, 712000, Xianyang, Shaanxi,China;Institute of Water Resources and Hydro-electric Engineering of Xi′an University of Technology, 710048, Xi′an, China;School of Geographical Sciences, Fujian Normal University, 350007, Fuzhou, China)

机构地区：[1]咸阳师范学院资源环境与历史文化学院,陕西咸阳712000 [2]西安理工大学水利水电学院,西安710048 [3]福建师范大学地理科学学院,福州350007

出　　处：《中国水土保持科学》2022年第1期56-64,共9页Science of Soil and Water Conservation

基　　金：国家自然科学基金重点基金“黄土坡地土壤养分随地表径流流失动力机制与模拟模型”(51239009);陕甘宁蒙能源富集区产业同构及跨区域协同发展研究(41661042);陕西省教育厅项目“西汉帝陵群环境演变与长时间序列土壤侵蚀研究”(20JZ100)。

摘　　要：为了研究榆林市还林还草工程的水土保持效益和土壤侵蚀变化趋势,用最小二乘法和神经网络模型预测研究区域未来植被覆盖和土地利用类型。结合中国坡面水蚀预报模型,计算2000—2017年土壤侵蚀序列,用最大、最小和多年平均降雨侵蚀力条件下模拟未来土壤侵蚀量。结果表明:1)丘陵沟壑区多年平均降雨侵蚀力在1150~1350 MJ·mm/(hm^(2)·h)之间,西部地区在800~1050 MJ·mm/(hm^(2)·h)之间,北部地区在1000~1150 MJ·mm/(hm^(2)·h)之间,2000—2017年平均降雨侵蚀力比1988—2000年增加268.24 MJ·mm/(hm^(2)·h);2)多年平均降雨侵蚀力下的土壤侵蚀模数由2000年的3559.99 t/(km^(2)·a)减少到2017年的1369.19 t/(km^(2)·a),土壤侵蚀量减少958.5万t;3)植被覆盖与管理因子C由2000年的0.164降低到2017年的0.069,预测C因子为0.053,还有一定的下降空间,但C因子的Hurst指数分析表明北部地区在未来干旱条件下,植被退化的风险较大;4)在多年平均降雨侵蚀力下,未来大多数地区的土壤侵蚀模数将<2000 t/(km^(2)·a),以轻度和微度为主;5)下一阶段还林还草的工作重点应该更加注重水资源承载力,以保障还林还草工程取得的水土保持生态效益。[Background]Yulin,located in the north of Shaanxi province,is one of the most serious soil loss and fragile districts of ecology in the middle reaches of the Yellow River in China.The ecological fragile environment causes threat for the sustainable development of economical society.The Grain for Green policy was launched by the Chinese government in 1999,resulting in the ecological environment nowadays becoming better.This indicated by the obviously reduced soil erosion.However,changes of soil erosion in the future are important to the ecological environment in Yulin city,which is related to the sustainable development of Grain for Green policy.[Methods]To investigate the benefit of soil and water conservation and the change trend of soil erosion under Grain for Green Project in Yulin,the Least Square Method and Neural Network Model were used to predict the vegetation cover and land use types in the future.The soil erosion series from 2000 to 2017 was calculated by the slope water erosion equation used in China.The future soil erosion modulus was simulated under the conditions of the min/max and the multi-year average rainfall erosivity.[Results]1)The annual average rainfall erosivity of the hilly and gully areas,western area and northern region ranged from 1150 to 1350 MJ·mm/(hm^(2)·h),from 800 to 1050 MJ·mm/(hm^(2)·h)and from 1000 to 1150 MJ·mm/(hm^(2)·h),respectively.Compared with from 1988 to 2000,the average rainfall erosivity of from 2001 to 2017 increased by 268.24 MJ·mm/(hm^(2)·h).2)The soil erosion modulus under the annual average rainfall erosivity decreased significantly from 3559.99 t/(km^(2)·a)in 2000 to 1369.19 t/(km^(2)·a)in 2017,and the amount of soil erosion decreased by 9.585×10^(6) t.3)The vegetation coverage(C)factors decreased from 0.164(year 2000)to 0.069(year 2017),and the predicted future C factor was 0.053.However,the Hurst index showed that the C factor in the future will increase up to 51%.This result shows that there is a risk of vegetation degradation in the future,especial

关 键 词：退耕还林(草)工程 土壤侵蚀预测 中国坡面水蚀预报模型 榆林市 

分 类 号：S157[农业科学—土壤学]