库尔勒香梨园土壤肥力空间变异特征与综合评价分析

Spatial Variability Characteristics and Comprehensive Evaluation Analysis of Soil Fertility in Korla Fragrant Pear Orchard

为研究库尔勒香梨园土壤pH、盐分、速效养分以及微量元素空间分布特征,掌握香梨园综合肥力水平,以库尔勒市香梨种植区为研究区,选取具有代表性的50个库尔勒香梨园进行样点布设与土样采集。运用经典统计学和地统计学方法研究香梨园表层(0~40 cm)土壤养分指标和微量元素指标的空间变异性,探究香梨园土壤肥力状况。经典统计分析表明:pH的变异系数为0.02属于弱变异,电导率的变异系数为1.03表现为强变异,有机质、碱解氮、速效磷、速效钾、有效锰、有效铜、有效锌和有效铁的变异系数分别为0.37、0.53、0.99、0.59、0.45、0.25、0.24和0.48,为中等变异程度,研究区土壤综合肥力指数IFI值在0.37~0.80之间,平均值为0.58;地统计分析表明:土壤有机质、碱解氮和速效钾的块金系数大于75%,空间自相关性较弱;pH、电导率、速效磷、有效锰、有效铜、有效锌和有效铁的块金系数在25%~75%之间,这些指标具有中等强度的空间自相关性;库尔勒香梨园Ⅰ(优)、Ⅱ(良好)、Ⅲ(中等)、Ⅳ(较差)和Ⅴ(差)类土壤占比分别为2.72%、10.54%、61.80%、24.87%、和2.77%,土壤综合肥力在空间上呈现斑块状,肥力较好的Ⅰ级在北部零星分布、Ⅱ级斑块状分布在北部及西部,Ⅲ级主要分布在北部以及南部,肥力较差的Ⅳ、Ⅴ级主要集中在中部。总体上,库尔勒市香梨园土壤肥力为中等水平,土壤属性空间异质性比较强,其中有效锰、有效铁是制约土壤肥力的主要限制因子,果园有必要进行差异化管理,并应重视补充锰、铁微量元素肥,此外中部地区还要着重补充氮肥、磷肥和有机肥。

To investigate the spatial distribution of soil pH,salinity,fast-acting nutrients,and trace elements in the Korla pear orchard,and to comprehend the comprehensive fertility level of balsam pear orchards,this paper designates the Korla fragrant pear planting area as its study domain.A total of 50 representative Korla fragrant pear orchards are selected for the deployment of sample point and subsequent soil sample collection.Classical and geostatistical methods are used to study the spatial variability of soil nutrient and trace element indicators in the top layer(0-40 cm)of pear orchards,and the soil fertility status of pear orchards are investigated as well.In classical statistical analysis,it is observed that the coefficient of variation for pH is 0.02,indicating a weak variation.Conversely,the coefficient of variation for conductivity is 1.03,showing strong variability.The coefficients of variation for organic matter,alkali-dissolved nitrogen,fast-acting phosphorus,fast-acting potassium,effective manganese,effective copper,effective zinc,and effective iron are 0.37,0.53,0.99,0.59,0.45,0.25,0.24,and 0.48,respectively,suggesting a moderate degree of variability in these parameters.The integrated soil fertility index(IFI)values within the study area range from 0.37 to 0.80,with a mean value of 0.58.Geostatistical analysis shows that the nugget coefficients for soil organic matter,alkaline dissolved nitrogen,and fast-acting potassium are all greater than 75%,indicating a weak spatial autocorrelation for these parameters.The nugget gold coefficients for pH,conductivity,fast-acting phosphorus,effective manganese,effective copper,effective zinc,and effective iron are all in the range of 25%~75%,suggesting moderately strong spatial autocorrelation for these metrics.The proportion ofⅠ(Optimal),Ⅱ(Well),Ⅲ(Medium),Ⅳ(Poor)andⅤ(Worse)soils in Korla pear orchards are 2.72%,10.54%,61.80%,24.87%,and 2.77%,respectively.The spatial distribution of integrated soil fertility exhibits a patchy pattern.The more fertile class I is dispersed in the northern region,while Class II shows a patchy distribution in both the northern and western areas.Class III is mainly located in both the northern and southern area.The less fertile classes IV and V are mainly concentrated in the central area.Overall,the soil fertility of balsam pear orchards in Korla City is of medium level.Soil properties are more spatially heterogeneous.Effective manganese and effective iron are the major limiting factors for soil fertility.Orchards should be managed differently.Orchards should be supplemented with manganese,and iron micronutrient fertilizer,and the central region should also focus on supplementing nitrogen fertilizer,phosphate fertilizer,and organic fertilizer.