基于最小数据集的高标准农田建设前后土壤养分综合评价

Comprehensive Evaluation of Soil Nutrients Before and After Constructing High-standard Farmland Based on Minimum Data Set

【目的】基于最小数据集对高标准农田建设前后土壤养分进行综合评价,为高标准农田建设评价提供理论依据。【方法】以甘肃省金塔县5个乡镇(东坝、古城、航天、西坝和中东)高标准农田建设前后的土壤为研究对象,测定耕层土壤有机质、全氮、速效磷、速效钾、pH、碱解氮、耕层含盐量和容重;采用主成分分析、相关性分析和Norm值计算的方法建立土壤质量评价最小数据集(Minimum data set,MDS),并构建土壤质量指数(Soil quality index,SQI)定量评价其土壤质量。【结果】高标准农田建设显著提高土壤有机质、全氮、速效磷、碱解氮和速效钾含量;降低土壤pH、耕层含盐量和土壤容重。构建的MDS包括有机质、全氮、速效磷指标;全数据集土壤质量指数(TDS-Soil quality index,TDS-SQI)和(MDS-SQI)在各乡镇均表现为建设后>建设前,且两种评价体系结果呈显著正相关(R^(2)=0.839,P<0.05)。【结论】采用最小数据集评价高标准农田建设前后土壤质量有较好的代表性和适合性,应用最小数据集评价高标准农田土壤质量是可行的。

【Objective】The soil nutrients before and after constructing high-standard farmland based on the minimum data set were evaluated comprehensively to provide the theoretical basis for evaluating high-standard farmland construction.【Method】Taking the soil before and after constructing high-standard farmland in 5 towns and townships(Dongba,Gucheng,Hangtian,Xiba and Zhongdong)of Jinta County in Gansu Province as the research object,the organic matter,total nitrogen,available phosphorous,available potassium,pH,available nitrogen,soil salt content and bulk density of the cultivated soil were measured,and then the minimum data set(MDS)for soil quality evaluation was established through principal component analysis,correlation analysis and Norm value calculation methods,finally the soil quality index(SQI)was constructed to quantitatively evaluate the soil quality.【Result】The construction of high-standard farmland significantly increased the contents of soil organic matter,total nitrogen,available phosphorus,available nitrogen and available potassium,and decreased the soil pH,soil salt content and soil bulk density.The constructed MDS included the indicators of organic matter,total nitrogen and available phosphorus.The total data set for soil quality index(TDS-SQI)and(MDS-SQI)in each town performed after the construction>before the construction,and the results of the two evaluation systems were significantly and positively correlated(R^(2)=0.839,P<0.05).【Conclusion】The evaluation of soil quality before and after constructing high-standard farmland through the minimum data set has better representativeness and suitability,which indicates that it is feasible to evaluate the soil quality of high-standard farmland by using the minimum data set.