成都盆地浅层土壤中元素来源研究

分形与多重分形已逐渐渗透到环境地球化学调查与评价领域,已有众多学者证实土壤及水系沉积物中元素含量的分布具有分形/多重分形性质。如何通过分形/多重分形模型来深入研究元素含量的空间分布特征并探究其来源问题,具有重要的理论和实际意义。本文通过浓度-面积分形方法,配合基本统计量、富集因子以及多元统计聚类分析对成都盆地12400km2范围内3061个浅层土壤样品和832个深层土壤样品中8种重金属元素及N、P、K、U等的分布模式及来源进行了初步探讨。结果显示,重金属等元素含量在成都盆地浅层和深层土壤中均具有多重分形特征,不同的分布模式能较好的判断表层土壤中元素的来源等问题,所得结果与传统统计学分析结果相吻合。该探索以期能为生态环境地球化学调查与评价提供新的视角。

C-A Fractal Model and Its Application in Distribution Patterns and Origin Identification of Elements in Top Soils at Chengdu Basin, China

Based on the C-A fractal model,together with some conventional statistical methods,the concentrations of 12 elements in 3082 samples from the top soil and 832 from the deep layers in Chengdu Basin were analyzed. The results showed that the contents of 8 heavy metals and N,P,K,U were multifractality in both top and deep soils. And different kinds of multifractal distribution patterns were helpful to determine the origin of elements in top soils. The C-A fractal analysis results were in agreement with those from conventional statistical methods,such as cluster analysis. The method used in this paper was expected to provide new insight into the geochemical environment assessment in the future.