天山南坡农区土壤养分空间分布特征

Spatial Distribution Characteristics of Soil Nutrients in Agricultural Areas on the Southern Slope of Tianshan Mountain

【目的】研究天山南坡农区土壤养分空间分布状况,分析土壤养分与地形因子间的相关关系。【方法】共采集研究区487个样品,土壤指标有pH、有机质、全氮、碱解氮、有效磷、速效钾。采用GIS和地统计学相结合的方法,研究区土壤养分的空间分布特征,并分析土壤养分含量与地形因子之间的相关性。【结果】土壤pH值的变异性最低,而有效磷和速效钾的变异系数最大,其他的变异系数较接近;全氮和有机质的相关性最强,碱解氮与其他土壤养分均达到极显著相关性,全氮和速效钾的相关性最弱;有机质和全氮含量偏低,碱解氮含量极低,而有效磷含量中等偏高,速效钾含量中等偏低;有机质、全氮和碱解氮的块金效应分别为44.99%、44.47%和49.83%,而有效磷和速效钾的块金效应分别为12.39%和15.16%;有机质的变程最大为0.936 km,其次是全氮、碱解氮,变程分别为0.873和0.582 km,有效磷和速效钾的变程分别为0.051和0.042 km。【结论】天山南坡农区土壤养分属于中等程度变异,区域内土壤养分存在的空间丰缺差异明显;有机质、全氮和碱解氮表现为中等空间相关性而有效磷和速效钾表现为强烈的空间相关性;地形因子对土壤养分含量的影响也较大。需有针对性地对天山南坡农区进行施肥指导和管理,合理增施氮肥和有机肥,适当施用磷肥和钾肥。

【Objective】This project aims to explore the spatial distribution of soil nutrients in the agricultural area on the southern slope of Tianshan mountain and analyze the correlation between soil nutrients and topographic factors.【Method】A total of 487 samples were collected in the study area.Soil indexes included pH,organic matter(OM),total nitrogen(TN),alkali-hydrolyzed nitrogen(AN),available phosphorus(AP)and available potassium(AK).The spatial distribution characteristics of soil nutrients in the study area were revealed by GIS and geostatistics,and the correlation between soil nutrient content and topographic factors was discussed【Result】The soil pH value had the lowest variation,while the AP and AK had the highest variation,and the other variation coefficients were close to each other;The correlation between TN and OM was the strongest,the correlation between AN and other soil nutrients was extremely significant,and the correlation between TN and AK was the weakest;The content of OM and TN was low,the content of AN was very low,the content of AP was medium high,and the content of AK was medium low;The gold nugget effects of OM,TN and AN were 44.99%,44.47%and 49.83%,respectively,while the gold nugget effects of AP and AK were 12.39%and 15.16%,respectively;The range of OM was 0.936 km at most,followed by 0.873 km and 0.582 km for TN and AN,respectively,and 0.051 km and 0.042 km for AP and AK,respectively.【Conclusion】The soil nutrients in the south slope of Tianshan were of moderate variation,and the spatial difference of soil nutrients was obvious.OM,TN and AN showed moderate spatial correlation while AP and AK showed strong spatial correlation.In addition,topographic factors have great influence on soil nutrient content.It is necessary to guide and manage the application of fetilizer in the south slope of Tianshan mountain,reasonably increase the application of nitrogen fertilizer and organic fertilizer,and appropriately apply phosphorus fertilizer and potassium fertilizer.