桂林毛村不同地质背景主要元素迁移特征及与植物蒸腾作用的相关性

对桂林毛村不同地质背景(石灰岩、白云岩和砂页岩)土壤中Ca、Mg、Cu、Fe、Mn、Zn等主要元素的迁移特征进行了研究,结果表明母岩的地球化学背景对岩溶土壤系统的元素迁移具有重要影响.同时,以不同地质背景生长的典型植物黄荆为例,研究了上述元素的迁聚与植物蒸腾作用的相关性.结果表明,植物蒸腾作用对土壤中Ca、Mg、Cu、Fe、Mn、Zn等主要元素迁聚的影响程度因不同地质背景以及不同元素而有明显差异.植物蒸腾作用对Mn、Cu等较难迁移元素的迁移具有一定促进作用.土壤中Cu、Fe、Mn、Zn等微量元素的迁聚对植物吸收系数的影响程度因不同地质背景而有显著差异.岩溶山区进行植被恢复时必须考虑不同地质背景的差异,因地制宜地选择合适的植物品种.

Characteristics of Main Elements Migration in Soils under Different Geological Backgrounds and Their Correlation to Plant Transpiration in Maocun, Guilin

Characteristics of migration of main elements including Ca, Mg, Cu, Fe, Mn and Zn in soils under different geological backgrounds (limestone, dolomite, sandshale) in Maocun, Guilin, were studied. The results showed that the geochemical backgrounds of parent rocks had important effects on element migration in Karst soil systems. On the other hand, the correlation between the migration of above elements and plant transpiration were studied, exemplified by a typical plant Vitex negundo grown under different geological backgrounds. The results showed that the influence extent of plant transpiration on the migration and accumulation of these main elements varied with different geological backgrounds and different elements. Plant transpiration could promote the migration of the elements to some extent, such as Mn and Cu, which were more difficult to transfer in soils. Moreover, the influence extent of migration and accumulation of these microelements on plant absorption coefficient, varied significantly with different geological backgrounds. In karst mountain areas, the differences among different geological backgrounds should be considered when conducting vegetation restoration, and suitable plant species should be chosen according to the local conditions.