伊犁河谷缓坡地融雪侵蚀特征研究

Erosion Traits of Melted-snow in Gentle-slope Land of Ili River Valley

采用坡面径流小区试验法,于2009年3月3～10日,对伊犁河谷缓坡地的春季融雪侵蚀特征进行了系统研究。结果表明:8°坡融雪强度始终较3°和5°坡的大,其径流强度的日变幅也最大;8°坡坡面日产流量和产沙量均最大,日产流量分别比5°和3°坡高24.5和28.7 mL/d,泥沙侵蚀量多4.23和5.85kg/m^3;坡度间坡面冲刷细沟的分布和细沟侵蚀强度也有差异,8°坡坡面的冲刷细沟多呈网状交错状,主要分布在坡面下部,冲蚀沟多而较长、浅且宽;5°和3°坡的冲刷沟则在坡面的中、下部呈分散状分布,冲蚀沟少而短、浅且窄;融雪后,0～20cm土层的土壤含水量表现为:8°坡显著低于5°3°坡。该研究结论将为伊犁河谷及干旱、半干旱区生态相似区域春季融雪径流的集蓄利用、侵蚀坡地的保护和治理提供了依据。

The erosion traits of melted - snow were studied during spring from March 3 to March 10, 2009, at Hi River valley slope land. The results were shown as follows： the intensity of runoff caused by melted - snow and the variety of runoff intensity per day on 8° slope - land were more than those on 5° slope - land and on 3° slope - land, respectively; meanwhile, the amount of runoff and the sand mass in runoff on 8° slope - land were 24.5 ml/ d and 4.23 kg/m^3 more than those on 5° slope - land and 28.7 ml/d and 5.85 kg/m^3 more than those on 3° slope - land, respectively. The distribution of water - erosion ditchs and erosion intensity of ditehs were different among those slope land in this study. On the 8° slope - land, most of the ditchs were long, thin and wide and distributed on the bottom of the slope land hke net; On the 5° slope- land and 3° slope- land, most of ditchs were short, thin and narrow and distributed on the middle and bottom of the slope land dispersedly. After thaw, on the 5° and 3° slope- land, the water content in 0 - 20cm soil layer were relatively high and there was no difference between them; but their soil water content were more than that of 8° slope - land significantly. So, by the study, some methods and suggestions were provided for conserving and restoring the erosion land in lli River valley or the land in some smilar arid areas.