云南省呈贡县蔬菜地表层土壤Pb Cu和Zn的小尺度空间分布特征

应用地统计学对云南省呈贡县蔬菜生产基地2个典型区域(湖滨区和平坝区)3种微量元素(Pb、Cu和Zn)含量和土壤理化参数(CEC、<0.01mm粘粒和有机质含量)进行了空间结构分析。结果表明:(1)Pb、Cu和Zn含量在湖滨区低于平坝区,湖滨区Pb含量的变异系数较大,达到88.7%;(2)Pb、Cu和Zn含量在不同方向上呈带状各向异性,方向都为WS-NE和SE-NW;(3)Pb、Cu和Zn含量表现出强烈的空间变异,空间相关度介于25%和75%之间。在湖滨区Pb的变异强度高,Cu和Zn在平坝区的变异强度大于湖滨区;(4)CEC在湖滨区受到随机因素引起的变异强度大于平坝区,而粘粒含量和有机质含量的空间相关度均介于25%和75%之间。Pb、Cu和Zn含量与CEC之间呈显著的负相关性;(5)5个相邻的温室大棚湖滨区Pb含量高度变异,Cu和Zn的变异系数小。平坝区各指标的变异系数接近。呈贡县蔬菜生产基地表层土壤Pb、Cu和Zn含量在小于1km2的尺度上表现出明显的空间变异性,空间变异与土壤结构、灌溉、耕作活动、管理水平、施肥水平、大棚蔬菜生产年限、地下水位、农田道路网络和城市排污沟渠的分布等有关。

Spatial Distribution of Pb, Cu and Zn in Periurban Market Garden Soil in Chenggong County, Yunnan Province

The spatial distribution of 3 trace dements(Pb,Cu and Zn)in lacustrine and transition units of periurban market garden in Chenggong County,Yunnan Province were studied with geostatistical analysis. The results showed that:(1)contents of Pb,Cu and Zn in lacustrine unit were lower than in transition unit. The variation coefficien(tCV)of Pb was 88.7% in lacustrine unit.(2)Pb,Cu and Zn showed anisotropy with direction WS-NE and SE-NW.(3)the spatial variations of Pb,Cu and Zn were significant. The nugget(C0)of P...