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自一九八二年至一九八四年,对阿肯色州南部两个自然地理条件完全不同的流域内自然植被在立木皆伐和机械整地造林后,对土壤的保护作用进行了研究,两地的自然植被在采伐和机械整地过程中都受到了同样方式和相同程度的破坏。采伐后沿海平原三条小流域内,裸土面积约占47%,而雅典高原的三条小流域内则为53%,这两地枯枝落叶层大约占总面积的38%,体型徽小的地被植物、树桩、树皮和其它木质废弃物所复盖的面积则相对减少,采伐一年后草本植物迅速占领了各小流域,裸土面积大大下降仅占5%,第二年则更为减少,海湾平原区仅占10%,雅典高原也仅占3%,海湾平原区地表迳流中沉积物的含量由采伐后第一年的208ppm 下降到第二年的14ppm。在雅典高原区,由于采伐后第二年有两次极大的暴雨,故沉积物的含量略有增加,由122ppm 提高到129ppm,即是如此,地表迳流中沉积物的浓度还是少于第一年。
From 1982 to 1984, the natural vegetation in the basin, two completely different natural and physiographic conditions in southern Arkansas, studied the protective effect of the soil after clearwood clearance and mechanical afforestation. Two places Of the natural vegetation in the logging and mechanical preparation process have been the same way and the same degree of damage. After harvesting, the bare soil area accounts for about 47% of the three small watersheds in the coastal plain after harvesting, while in the three small watersheds of the Athenian Plateau, it is 53%, and the litterfall layer accounts for about 38% of the total area. The covered area of ground cover plants, tree stumps, bark and other wood waste decreased relatively. One year after the harvesting, the herbaceous plants rapidly occupied small watersheds, with a barely 5% reduction in bare soil area and the second year even more For the sake of reduction, only 10% of the Gulf Plain and only 3% of the Athenian Plateau sediments in the surface sediment of the Gulf Plain decreased from 208ppm in the first year after logging to 14ppm in the second year. In the plateau area of Athens, the sediment content slightly increased from 122 ppm to 129 ppm due to two extremely heavy rains in the second year following harvesting, One year