辽西北沙地苹果-花生间作系统土壤养分空间分布特征及间作效应

目的] 研究辽西北沙地农林复合系统土壤养分的空间分布及其效应，从土壤养分角度探讨果农间作系统中果树和农作物对土壤养分的相互作用关系，为该区农林复合系统的可持续经营提供科学合理的依据。方法] 以苹果与花生间作、花生单作、苹果单作为研究对象，对0-60 cm土层深度，0-300 cm水平距离范围内土壤养分含量进行测定和分析。结果] 沙地间作系统中土壤有机质、速效钾极缺乏，全氮、碱解氮很缺乏，全磷缺乏，有效磷含量中等；间作系统在水平方向上，苹果树和花生植株对总养分有机质、氮、磷的竞争激烈位点位于果树带区，对有效养分氮、磷、钾的竞争激烈位点位于近果树作物区；在垂直方向上，各养分总体表现出了表聚性，间作系统对有机质、有效磷的竞争主要位于深土层，对全磷、速效钾的竞争主要位于表土层，对全氮、碱解氮表现为合作效应，表土层效应更高；与苹果单作、花生单作相比较，间作系统速效钾和有效磷含量呈现负效应。结论] 沙地苹果-花生间作系统土壤养分贫瘠，应在果树带区施用有机肥、磷肥，作物区施入钾肥，以减轻养分竞争，提高养分效应。

Spatial Distribution Characteristics of Soil Nutrients and Intercropping Effect in Sandy Land Apple-peanut Intercropping System in Northwest Liaoning Province

Objective] The spatial distribution and effects of soil nutrients in the agro-forestry system in sandy land were explored in order to provide scientific basis for the sustainable management of the agroforestry system from a perspective of soil nutrients in the region of Northwest Liaoning.Methods] Soils in apple-peanut intercropping, peanut monoculture, and apple monoculture were sampled to determine and analyze soil nutrients contents in the range of 0-60 cm and 0-300 cm horizontal distance.Results] Total organic matter and available potassium were extremely deficient, the total nitrogen and available nitrogen were very deficient, total phosphorus was deficient, and the available phosphorus content was medium in the intercropping system of sandy land. In the horizontal direction of the intercropping system, the intense competition sites for total organic matter, total N and total P for apple trees and peanut plants were located in the fruit tree zone, and the intense competition sites for available nutrients of N, P and K were located in the near fruit trees. In the vertical direction, all nutrients showed surface aggregation. The competition of organic matter and available phosphorus in the intercropping system was mainly located in the deep soil layer, and the competition of total phosphorus and available potassium was mainly located in the top soil layer. There was a cooperative effect on total nitrogen and available nitrogen, and the effect in soil of surface layer was more obvious. Compared to peanut monoculture and apple monoculture, the contents of available potassium and available phosphorus in the intercropping system showed a negative effect.Conclusion] Soil nutrients in the apple-peanut intercropping system were poor. Organic fertilizers and phosphate fertilizers are recommended to be applied in the fruit tree zone, and potassium fertilizer should be applied in the crop area so as to reduce nutrient competition and improve nutrient effect.