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机构地区:[1]中国科学院寒区旱区环境与工程研究所,兰州730000
出 处:《应用生态学报》2004年第9期1536-1540,共5页Chinese Journal of Applied Ecology
基 金:中国科学院知识创新工程项目 (KZCX3 SW 3 2 9);中国科学院重大资助项目 (KZCX1 0 9 0 2 )
摘 要:20 0 1年~ 2 0 0 2年 ,在河西走廊中断黑河中游 ,研究了不同方式对春季就地起沙、风速梯度、水分保持等方面的效应 .结果表明 ,冬灌免耕、粮草间作和早春覆膜措施都不同程度地遏制了就地起沙 ,减少了土壤风蚀 .早春覆膜在减少土壤风蚀量的同时 ,提高了土壤蓄水量 ,比春耕裸露农田蓄水量增加了35 6 % .目前 ,春耕播种裸地是形成沙尘暴和浮尘的粉尘含量的主要来源之一 ,黑河中、上游农田耕地每年产生的粉尘输移量达 4 8× 10 6~ 6 0× 10 6t,高于同区域沙漠粉尘输移量 .河西走廊粉尘输移量 1hm2 农田相当于 1 5hm2 沙漠 .During 2001~2002,the effects of different cultivation modes including winter irrigation and zero tillage,crop-grass intercropping,and early spring film mulching on sand entrainment,wind velocity gradient and soil moisture conservation were studied in the middle reaches of the Heihe River in the Hexi Corridor region.The results showed that all these modes could reduce soil wind erosion and halt sand entrainment to different degrees.Compared with the bare fields exposed by spring plowing,early spring film mulching could increase soil moisture storage by 35.6%.At present,spring plowing and sowing was a main factor responsible to the occurrence of sand storms and the increase in suspended dust content.Farmlands in the upper and middle reaches of the Heihe River generally produced a dust transport up to 4.8~6.0 million tons per year,which was higher than that of sandy desert in the same region.In the Hexi Corridor region,the suspended dust amount produced from 1 hm 2 farmland was equivalent to that of 1.5 hm 2 desert.
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