北京市大兴区不同类型果园土壤肥力和环境质量研究

Soil fertility and environmental quality of different types of orchards in Daxing district,Beijing

针对北京市大兴区主要栽培果树品种土壤肥力特征与土壤环境质量认识不清的问题,以大兴区规模化果园为研究对象,采用田间随机取样的方法,对梨、桃、葡萄等主要栽培类型的果园土壤肥力特征和环境质量进行研究,以期为规模化果园的科学管理与高效施肥提供参考。结果表明,除葡萄园有机质(平均为1.28 g/kg)和全氮(平均为23 g/kg)等级较高外,其余果园普遍处于中、低或中、高等级,尤其是梨园较低,果园的有效磷、速效钾处于过量状态;约40%的园区土壤全盐量≥0.8 g/kg,次生盐渍化趋势较为明显,土壤主要呈弱碱性与碱性(pH范围为7.69~8.95);部分果园表现出土壤有效态硫、钼、锰和硼等中微量元素缺乏的现象;监测果园均未表现出土壤重金属超标现象。总体而言,葡萄园的肥力普遍较高,而梨园普遍较低;果园存在氮磷钾和中微量元素营养失衡等问题,建议推广氮磷钾平衡施肥,增施微肥,实现大量和中微量元素均衡供应的目标;同时加强水肥管理,避免加重土壤次生盐渍化程度和连续有机肥施用可能导致的土壤重金属快速累积,从而实现规模化果园的清洁高效生产。

In order to provide a reference for scientific management and efficient fertilization in large-scale orchards in Daxing district,Beijing,the soil fertility characteristics and environmental quality of the main cultivation kinds of orchards such as pear,peach and vineyards were studied in this study,using the method of random sampling in the field.The results showed that,except for the higher soil organic matter(1.28 g/kg on average)and total nitrogen(23 g/kg on average)grades in the vineyard,the soil organic matter and total nitrogen in the rest of the orchards were generally in the medium-low or mediumhigh grades,especially was medium-low in the pear orchards,and the soil available phosphorus and potassium grades in the orchards were excessive.About 40%of orchards had an obvious trend of secondary salinization(soil total salinity≥0.8 g/kg),and the soil were mainly weakly alkaline and alkaline(pH ranged from 7.69 to 8.95).In addition,some orchards showed lack of medium and trace elements such as soil available S,Mo,Mn,and B;and none of the monitored orchards showed excessive heavy metals in the soil.In general,the fertility in vineyards are generally high,while those in pear orchards are generally low.There are problems such as nutritional imbalances of nitrogen phosphorus potassium,medium and trace elements in orchards.It is recommended to continue to carry out soil monitoring,promote nitrogen phosphorus potassium balanced fertilization,and increase the application of micro-fertilizer to achieve the goal of balanced supply of macro,medium and trace elements.At the same time,water and fertilizer management should be strengthened to avoid aggravating the degree of secondary soil salinization and heavy metals accumulation in the soil caused by continuous application of organic fertilizers,so as to achieve clean and efficient production in large-scale orchards.