考虑微生物要素的土壤质量综合评价——以北京市平谷区为例

Comprehensive evaluation of soil quality considering microbial elements:a case study of Pinggu District, Beijing,China

为探讨北京市平谷区土壤质量现状,本研究在传统的土壤质量综合评价体系基础上考虑了微生物要素,基于实地网格土壤采样的228个样本,从土壤肥力、土壤环境、土壤微生物3个维度选取11项土壤指标,采用土壤质量指数法定量分析各指标并计算土壤质量指数,综合评价北京市平谷区的土壤质量。结果表明:平谷区土壤质量综合指数(ISQI)在良好到优等范围内(0.60~0.96),平均值为0.74,平均土壤质量综合评价等级为良好。空间分布上整体呈现南低北高、西低东高的特征,北部熊儿寨乡、黄松峪乡及东部金梅湖镇等地区多为山地或林地,植被丰富,人为活动强度弱,土壤肥力水平高且微生物较为丰富,土壤质量综合评价等级相对较高;而西南部马坊镇、马昌营镇等地区土壤肥力水平低,微生物数量较少,综合质量评价等级相对较低。熊儿寨乡的ISQI最高,为0.81;平谷镇的ISQI最低,为0.64。平谷区不同土地利用类型ISQI排序为果园>林地>荒地>菜地>农田。研究表明,北京市平谷区土壤质量综合评价等级为良好,但空间差异明显,东北部多为山地和林地,综合评价等级为优等,中部及西南部多为农田菜地,综合评价等级为良好和中等,未来应注重科学施肥和土壤质量管理。

To explore the current status of soil quality in Pinggu District,Beijing,this study considered microbial factors based on the traditional comprehensive evaluation system of soil quality.A total of 228 samples were collected using grid-based sampling,and 11 soil indicators were selected considering the three dimensions of soil fertility,soil environment,and soil microorganisms.The soil quality index method was used to quantitatively analyze each indicator and calculate the soil quality index to comprehensively evaluate the soil quality in Pinggu District,Beijing.The results showed that the Integrated Soil Quality Index(ISQI)of Pinggu District ranged from good to excellent(0.60–0.96),with a mean value of 0.74,and the average integrated soil quality evaluation grade was good.Overall spatial distribution showed that areas with low values were in the south and west,whereas high values were obtained in the north and east,respectively.The northern areas,such as Xiong′erzhai,Huangsongyu,and east area Jinmeihu,were mostly in mountainous or woodland regions,rich in vegetation with few human activities,with high levels of soil fertility,rich in microorganisms,and had a relatively high overall soil quality evaluation grade,whereas the southwestern areas,such as Mafang and Machangying towns,had low levels of soil fertility and few microorganisms,and a relatively low overall quality evaluation grade.The comprehensive quality evaluation grade was relatively low.The ISQI of Xiong′erzhai Town was the highest at 0.81 and that of Pinggu Town was the lowest at 0.64.The order of ISQI for different land use conditions in Pinggu District was orchard>forest land>wasteland>vegetable land>farmland.The results showed that the comprehensive evaluation grade of soil quality was good but different in spatial distribution in Pinggu District,Beijing.The northeastern part was mostly mountainous and forested,with a comprehensive evaluation grade of excellent;the central and southwestern parts were mostly agricultural vegetable land,with the comprehensive evaluation grade of good and medium,and should focus on scientific fertilization and soil quality management in the future.