黄土丘陵区人工林地土壤肥力质量

Soil fertility quality of artificial forest in the Hilly-gully region of Loess Plateau

以黄土高原北部的陕西省吴起县为例，通过对不同灌木类型和不同生长年限的乔木林地土壤样品的分析测试与数理统计，研究黄土丘陵沟壑区不同人工林植被对土壤肥力质量的影响。结果表明：1）土壤碱解N和速效K，柠条林地是沙棘林地的2倍以上，二者之间达到极显著差异水平；柠条对土壤肥力的提高效果要优于沙棘，仅从对土壤性质的改善来看，建议选择种植柠条。2）乔木林地，从幼年林地到成年林地，土壤全N、碱解N、有机质和阳离子交换量不断增加，土壤速效K、全P和速效P略有增加，土壤有机质和养分的表聚性加强。3）总体上，乔木林地0～100cm土层土壤碱解N、速效K、有机质、阳离子交换量、全N、全P、全K均高于灌木林地，表明乔木林地对土壤的培肥效果优于灌木林地。

Taking Wuqi County of Shaanxi Province as an example, in order to compare the effects of the different plantation on the soil fertility in Hilly-gully region, the determination analysis of soil samples and the mathematical statistic were carried on the different shrub and the arbor tree land. The result indicated ： 1 ） The soil AN and AK content of Caragana intermedia was the twice of Hippophae rhamnoides, there was the extremely remarkable level between them. The improving effect of soil fertility of Caragana intermedia was better than Hippophae rhamnoides. Only from the improving of soil fertility, it is suggested to plant Caragana intermedia as a good choice. 2） From the young-age of arbor tree land to the mature wood, the soil TN, AN, OM and CEC content was unceasingly increases, the soil AK, TP and AP content had the slight increase, the surface gathering of soil OM and nutrient was obvious and strengthening. In overall, in 0 - 100 cm soil layer of arbor tree land, the soil AN, AK, OM, CEC, TN, TP and TK content were higher than those of the shrub land. It indicated that the contribution to soil fertility of arbor tree land was better than that of the shrub land.