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在三处径流场共２８个径流小区进行的多年定位研究结果表明：炼山、整地、抚育等营林措施，均造成杉木幼林地不同程度的水土流失。炼山造成的水土流失最为严重，炼山后六年的土壤流失量达３８．００４ｔ·ｈｍ￣（－２），是不炼山林地的１９．７倍，其中第一，二年的流失量为２４．８１１ｔ·ｈｍ（－２）和１０．３１６ｔ·ｈｍ（－２），分别是不炼山林地的８８倍和２８倍，占六年总量的９２．４３％，不同整地方式林地土壤流失量表现为全垦＞带垦＞穴垦，它们的比值是１．６：１．２：１．Ｏ不同抚育方式土壤流失量则为扩穴连带抚育＞块状抚育＞不抚育，前二种土壤流失量均超过了中度侵蚀的标准。
The results of multi-year positioning study conducted in 28 runoff areas at three runoff sites showed that silviculture, land preparation and tending have caused different degrees of water and soil loss in the young forests of Cunninghamia lanceolata. The soil erosion caused by the refining is the most serious. After six years of refining, the amount of soil loss reached 38.004t · hm -2, which is 19.7 times of that of the non-mountainous forest, of which the first and second year’s loss 24.811 t · hm (-2) and 10.316 t · hm (-2), respectively, which were 88 times and 28 times that of non-flowering forestland, accounting for 92.43% of the total in six years. The total amount of loss represented by Reclamation> Reclamation> Reclamation, their ratio is 1.6: 1.2: 1. However, the amount of soil loss in different ways of tending was enlarged by coalescence> mass nurturing> non-tending. The former two types of soil loss exceeded the standard of moderate erosion.