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以2年生杨-农复合系统为研究对象,通过对不同林分结构(密度、配置方式)杨-农复合系统及农田土壤养分的分布特征进行分析比较,探讨林分结构对杨-农复合系统土壤养分的影响规律。结果表明:(1)杨-农复合系统土壤含水率、pH值、有机质、全氮、全磷和全钾含量在0~20 cm和20~40 cm土层均存在明显的水平差异,但距杨树树行不同距离点土壤养分的变化规律性不明显,可能受杨树根系分布、土壤微生物、施肥以及耕作等的影响;3种模式杨-农复合系统土壤含水率、pH值均高于对照,全氮含量仅树干基部土壤低于对照,而全磷、全钾含量与对照间差异不明显;(2)4种类型土壤含水率、pH值、有机质、全氮、全磷和全钾含量在上下层间呈极显著差异(P<0.01),存在明显的垂直分布规律,且M1模式上层土壤含水率、pH值、有机质、全氮含量高,全磷与全钾含量低,M2与M3模式多相反。
Based on the analysis of the distribution characteristics of Yang-agroforestry system and farmland soil nutrients under different stand structure (density and disposition), the two-year Yang-agroforestry system was studied. Soil nutrient influence law. The results showed that: (1) The soil water content, pH value, organic matter, total nitrogen, total phosphorus and total potassium content in Yang-agroforestry system were significantly different at 0-20 cm and 20-40 cm soil layers, The variation regularity of soil nutrients at different distance points of poplar trees was not obvious, which may be affected by root distribution of poplar, soil microorganism, fertilization and tillage. The soil water content and pH value of poplar-poplar system were higher than the control, The content of total nitrogen was only lower in the trunk than in the control, but there was no obvious difference between the total phosphorus and the total potassium in the soil. (2) The contents of soil water, pH, organic matter, total nitrogen, total phosphorus and total potassium There was a significant vertical distribution in the upper and lower strata (P <0.01). There was obvious vertical distribution in the upper and lower strata. The soil moisture content, pH value, organic matter and total nitrogen content in upper M1 model were higher than those in M1 and M2, On the contrary.