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以RS、GIS和RUSLE模型结合SEDD模型,分析了退耕还林前后北洛河上游流域1990年、2000年和2010年土壤侵蚀强度和产沙量的时空变化特征。结果表明:3个时期年平均土壤侵蚀模数分别为18189.72,7 408.93,2 857.76t/(km~2·a),年均输沙模数分别为14 093.31,5 997.65,2 394.37t/(km~2·a),均呈减小趋势。3个时期的土壤侵蚀量在地形上的分布表现出趋同性,即高程上均在1 475~1 575m内平均侵蚀模数和侵蚀量表现出最大值。随着坡度增加,平均侵蚀模数增加,流域内75%以上的侵蚀量均来自于坡度>15°区域。3个时期平均侵蚀模数均遵循阳坡>半阳坡>半阴坡>阴坡的规律。研究为该区域生态环境建设效益评价及水土资源合理利用提供有益信息。
The spatial and temporal variations of soil erosion intensity and sediment yield of the upper and lower Beiluohe watershed in 1990, 2000 and 2010 before and after the conversion of cropland to forest were analyzed by using RS, GIS and RUSLE models together with the SEDD model. The results showed that the average soil erosion modulus of the three periods were 18189.72, 7 408.93 and 2 857.76 t / (km ~ 2 · a), respectively. The average annual sediment transport modulus was 14 093.31, 5 997.65 and 2 394.37 t / km ~ 2 · a), all showed a decreasing trend. The distribution of soil erosion in the three periods shows the same distribution in the terrain, that is, the average erosion modulus and the erosion amount show the maximum within 1475 ~ 1575m on the elevation. As the slope increases, the average erosion modulus increases and more than 75% of the erosion in the basin comes from the slope> 15 °. The average erosion modulus in three periods followed the law of sunny slope> semi-sunny slope> semi-shady slope> shady slope. The research provides useful information for the benefit evaluation of ecological environment construction and the rational utilization of water and soil resources in this area.