山东主要果园土壤的粘土矿物组成及其吸附特性

Composition of Clay Minerals and Adsorption Characteristics of Main Orchard Soils in Shandong

研究了山东主要果园土壤中粘土矿物的组成、类型及其对P、K和Cu、Zn、Pb金属元素的吸附特性。结果表明:山东主要果园土壤的粘土矿物类型存在着明显的差异,淋溶较强,酸度较大的棕壤(简育湿润淋溶土)中粘土矿物以高岭石占优势,对P的吸附较强,但对K+吸附固定较弱。含游离C aCO3较高的潮土(淡色潮湿雏形土)和褐土(简育干润淋溶土),对P有较强的吸附和沉淀作用,使土壤磷的有效性降低。而砂姜黑土(钙积潮湿变性土)由于含有较高的蒙脱石和1.4 nm过渡矿物,对K+具有很强的吸附和晶穴固定作用,因此砂姜黑土中磷肥和钾肥的有效性均较低,在施肥上应采取集中施肥和保持较湿润土壤环境等措施,以提高养分有效性。砂姜黑土和潮土对Cu、Zn、Pb金属元素的吸附显著地大于棕壤和褐土,主要的影响因素是不同土壤的粘粒含量和粘土矿物的类型的差异。同一土壤对Pb的吸附量远远大于对Zn和Cu的吸附量,主要取决于金属元素本身的化学性质和胶体的吸附特性。

The composition of clay minerals and adsorption characteristics on P, K, Cu, Zn, Pb of main orchard soils in Shandong province were studied. The results show that the composition of clay minerals was different between different soil types in Shandong main orchard soils. The kaolinite was the dominant mineral type in brown soils （Hap-Udic Luvisols） with high leaching and lower soil pH. This soil expressed a strong adsorption on phosphorus, but less or weak fixation on potassium. The availablity of phosphorus was relatively low for the Cao soils （Och-Aquic Cambosols） and cinnamon soils （Hap-Usdic Luvisols）, due to the high adsorption, high carbonate content and chemical precipitation action. Because Shajiang black soils （Cal-Aquic Vertosols） contained large amount of montmorillonite and 1.4 nm interlayer minerals, this soils displayed a strong adsorption capacity and crystal lattice fixation on potassium. Therefore, the availability of phosphate and potash fertilizers in Shajiang black soils were lower than that in brown soils. The adsorption ability and capacity on heavy metals of Cu, Zn, Pb in Shajiang black soils and Cao soils was significantly greater than that in brown soils and cinnamon soils, the dominant influence factors were the differences in clay content, clay mineral types and their composition among different soil types. The adsorption capacity on Pb was far greater than that on Zn and Cu in the same soils, which was mainly dependent on the chemical property of these elements and the adsorption characteristics of the colloids.