山东省乡镇尺度土壤肥力空间分布特征研究

Spatial Distribution Characteristics of Soil Fertility in Township Scale of Shandong Province

乡镇尺度上的土壤肥力指标能够代表当地的基础地力,而且还可以有效地指导科学施肥。本研究选择山东省1504个农业乡镇为研究对象,通过主成分和空间聚类分析方法,研究了山东省土壤肥力空间分布规律,以及丰缺敏感区域。主要研究结果如下:(1)山东省乡镇尺度上土壤有机质、全氮、有效磷和速效钾的平均含量分别为(12.93±0.1) g/kg、(0.87±0.01) g/kg、(31.89±0.51) mg/kg和(128.64±1.48) mg/kg;利用土壤质量综合评价方法,将山东省各个乡镇土壤肥力分为优、中和差3类,所占比例分别为14.20%、46.67%和39.13%;总体上,山东省土壤肥力质量处于中等偏下水平,中等及以下的乡镇占总体比例为85.8%。(2)山东省土壤肥力空间分布呈现北低南高的趋势,自西向东呈现先升高后下降的趋势。其中土壤肥力相对高的地区以中部为中心,成发散式、环形分布,且途经潍坊市中部—淄博市—临沂市东北及东南部—枣庄西部与济宁连接处,构成一个S型;山东半岛东南部地区土壤综合系数较低,有机质和速效钾为主要限制因子;中南部、西南部及东南部地区土壤肥力等级较低的主要原因是有效磷和速效钾的含量较低;西北和北部地区,土壤肥力主要限制因子为全氮和有效磷。本研究结果对有针对性地制订适宜山东省不同区域的土壤肥力提升方案具有指导意义。

The soil fertility indicators on the'township scale can embody the local basic soil fertility,and can also guide scientific fertilization effectively.The spatial distribution of soil fertility in 1504agricultural towns of Shandong Province was studied by principal component analysis and spatial cluster analysis.The results showed that:(1)the content of organic matter,total nitrogen,available phosphorus and available potassium was (12.93±0.1)g/kg,(0.87±0.01)g/kg,(31.89±0.51)mg/kg and (128.64±1.48)mg/kg,respectively,based on the comprehensive score of soil quality,the soil fertility of each township in Shandong Province was divided into three categories:fertile,moderate and barren,accounting for 14.20%,46.67%and 39.13%,respectively; conclusively,the quality of soil fertility in Shandong was at a lower level,and the proportion of middle and below was 85.8%;(2)the spatial distribution of soil fertility in Shandong increased first and then decreasedfrom north to south,increased and then reduced from west to east;the region with relatively high soil fertility was centered on the central part,with divergence and ring-like distribution;via the central part of Weifang City,Zibo City,the northeast and southeast of Linyi City,the junction of the west of Zaozhuang City and Jining City,constituted a S-type;the southeastern Shandong peninsula had low soil coefficient,organic matter and available potassium were the main limiting factors,and the main reason for the lower soil fertility grade in the south-central,southwestern and southeastern regions were the low content of available phosphorus and available potassium;total nitrogen and available phosphorus were the main limiting factors of soil fertility in the northwest and northern regions.The results of this study have guiding significance for the targeted formulation of soil fertility improvement programs appropriate for different regions of Shandong Province.