Spatial pattern of cultivated layer thickness and its influencing factors in typical area of Shanxi province
均匀随机地选取山西省 9个县市，以各县农田耕作层作为研究对象，测定各县全区样点的耕作层厚度、有机质、质地等理化性状，同时收集各样点的多年的气象数据、高程、耕地坡度、最高地下水位等信息；利用地统计方法分析各县农田耕作层厚度的空间变异特征，采用相关性分析和方差分析讨论了农田耕作层厚度空间分布的影响因素。结果如下:①灵丘县的耕层厚度整体平均水平最大，均值为 32.18 cm，隰县最小，均值为 7.06 cm；介休市的耕层厚度变异系数最大，为 27.56%，天镇县最小，为 5.43%；②朔州城区、介休市、隰县的耕层厚度最优半变异函数为球状模型，天镇县、岚县、阳曲县、壶关县为高斯模型最优，灵丘县和垣曲县为指数模型最优；③天镇县、隰县耕层厚度整体偏低，灵丘县整体偏高，朔州城区、岚县、壶关县均为四周高中部偏低的格局；垣曲县、阳曲县为四周偏低而中部偏高的格局，介休市为北高南低；④在影响耕作层厚度的各因素中，距村距离、海拔、降水量和无霜期对耕层厚度表现为负相关(P<0.01)，田面坡度、有效积温和有机质含量对耕层厚度表现为正相关(P<0.01)，种植作物、地貌类型、土壤质地、成土母质、土壤类型、土壤结构也对耕层厚度构成影响。耕层厚度空间分布特征以结构性为主，耕层厚度由人为因素和自然因素共同作用影响。
The cultivated soil layers in nine counties were selected as research objects to measure the physical and chemicalproperties，such as thickness，organic，texture，etc.，and multi-year meteorologicaldata，elevation，cultivatedlayerslope，maximum groundwater level and other information of sampling sites werecollected.The spatial structure and randomness of cultivated layer in each county were analyzed by geo-statistics method to get the spatial distributioncharacteristics of cultivated layer in eachcounty.Correlation analysis and variance analysis were used to get the influencefactors of the spatial distribution.Results showed as follows:(1)The average thickness of cultivated layer in Lingqiucounty was thelargest，and the mean value was 32.18cm；It was the smallest in Xicounty，and the mean value was 7.06cm；The coefficient of thickness variation of cultivated layer in Jiexiu city was the largest(27.56%)，and in Tianzhencounty was smallest(5.43%).(2)In Shuozhoucity，Jiexiu city and Xicounty，the optimal semi -variogram for thethickness of cultivated layer was expressed by spherical model，but it was fit for gaussian model in Tianzhen county，Lancounty，Yangqu county and Huguancounty，and in Lingqiu county and Yuanqu county it was best expressed by exponentialmodel.(3)The thickness of cultivated layer in Tianzhen county and Xi county wasthin，in Lingqiu county washeavy.In Shuozhoucity，Lancounty，Huguancounty，the thickness was heavier in the around area than thecentral.On thecontrary，in Yuanqu county，Yangqu county，the thickness was heavier in the central area than the around.Jiexiu city’s higher in northern than southern.(4)In influence factors of thickness of cultivated layer，the distance from thevillage，altitude，rainfall，and frost -free period were in negative correlation(P<0.01)，the slope of field and the effectiveaccumulated temperature and organic matter content on the thickness of cultivated were in positive correlation(P<0.01).The thickness of cultivated layer were influenced by planting crops，landforms，soiltexture，soil parent material，soiltype，and soilstructure.Spatial distribution of thickness of cultivated layer had twocharacteristics:randomness andstructural，inwhich the structural played a dominantrole.Thickness of cultivated layer was affected by both human and naturalfactors.