摘要
基于经典统计学和地统计学方法对乌兹别克斯坦表层土壤元素的组成和空间特征进行了研究。首先对土壤元素含量平均值、变异系数等特征进行了计算,比较了土壤元素含量特征。乌兹别克斯坦表层土壤Ca、Na、Mg等化学活动性元素的含量以及Co、Be、K、Zn等元素的含量偏高,而Al、Fe等其余元素含量相较于世界土壤中值偏低,变异系数也较小。元素含量的聚类分析表明,Ca、Sr、Mg、Na等化学活动性元素和Al、Fe等其他元素的特征差异较大。在此基础上,运用Gs+软件对乌兹别克斯坦土壤表层元素含量的空间异质性进行了分析。结果表明:土壤中Al、Fe、Be、K、Ti等元素具有强烈的空间自相关性;Cu、Pb、Zn、P等元素的空间结构显然已受到一些施肥、污灌、工农业生产等小尺度因素的影响,但整体上还没有达到破坏其原有空间格局的程度。化学活动性元素Ca和Sr除受土壤母质的影响外,还受到一定程度的局部随机因素的影响,在抽样尺度下没有空间相关性。另外,采用瑞典科学家Hakanson潜在生态危害系数法对土壤中重金属元素的潜在生态危害性进行了初步评价,乌兹别克斯坦土壤表层元素重金属Cu、Cr、Zn、Pb的潜在生态危害程度均为轻微,其中Zn和Cu危害程度最高,这与当地的社会经济发展状况一致。
The element contents and its spatial characteristics in Uzbekistan topsoils were studied with the methods of classic statistics and geostatistics. Firstly, using the software SPSS 15.0 for windows, the average values and coefficient variations of topsoil elements were calculated. The element contents(Ca, Na, Mg, Co, Be, K and Zn) of Uzbekistan are higher than their median values of world soil, and the other, the stable elements such as Al and Fe are lower. The geochemical active elements(Ca, Sr, Mg and Na) have significant differences with the stable elements such as Al, Fe and so on. Then, the element contents and its spatial distribution in Uzbekistan were analyzed with the software of Gs+. The results showed that the stable elements(Al, Fe, Be, K and Ti) in the topsoil have a strong spatial autocorrelation; the heavy metals(Cu, Pb and Zn) and nutrient element P are influenced by the small-scale factors including fertilization, irrigation, industrial and agricultural production, which have not yet reached the extent of the destruction of their original spatial patterns. The geochemical active elements(Ca and Sr) are affected not only by the soil parent material but also by a certain degree of local random factors, which lead to no spatial autocorrelation. In order to assess the current status of heavy metals in Uzbekistan topsoils, Hakanson potential ecological risk index was used to conduct a preliminary assessment of potential ecological dangers of heavy metals in Uzbekistan topsoil. The potential ecological risk index of Cu, Cr, Zn and Pb are small and the degree of ecological hazard is light, which is consistent with the Uzbekistan′s social and economic development.
出处
《农业环境科学学报》
CAS
CSCD
北大核心
2013年第2期282-289,共8页
Journal of Agro-Environment Science
基金
国家国际科技合作计划(2010DFA92720)
中科院重要方向性项目(KZCX2-EW-308)
西部之光项目(XBBS201106)