土壤酸化空间信息模型构建及其在贵州龙里实验区的应用

The structure of the soil acidification spatial information module and its application at an experiment station in Longli of Guizhou Province

依托遥感和地理信息系统理论和技术,基于TM数据、气象资料和化学实测数据,将基于能量循环的土壤水平衡模型和基于物质循环的土壤酸化模型相耦合,构建了土壤酸化空间信息模型,解决了土壤化学性质从点尺度到空间尺度的扩展.并以季节尺度模拟了酸沉降对土壤化学性质的影响,分析了贵州省龙里县2007年不同植被类型覆盖土壤受酸沉降影响的定量变化特征,结果表明,①从空间角度来说,在同一季节内,不同植被覆盖类型土壤水的pH值和土壤盐基饱和度的大小关系为:草地>混交林>灌丛>针叶林;②从时间角度来说,土壤水盐基浓度主要与土壤水含量呈负相关性,即浓度随着土壤水含量的增加而降低.不同季节相同指标的浓度由高到低为:春季>秋季>冬季>夏季;③不同植被覆盖类型土壤受相同酸沉降的影响不同,受酸雨影响由大到小为:针叶林>灌丛>混交林>草地.

A soil acidification spatial information model is built based on remote sensing and GIS tools, using TM remote sensing data, meteorological data and chemical compositions of soil and precipitation as input parameters. The model consists of a coupled soil water balance module based on an energy cycle and a soil acidification module based on a material cycle. The model can be used to analyze the soil chemical properties under the stress of acid deposition. The spatial scale of the model is also expanded from point to area in order to study the spatial distribution of soil properties. As a case study, the soil acidification process is simulated on a seasonal scale at Longli of Guizhou province in 2007, and the impacts of acid deposition on the soil covered by different types of vegetation are studied. The results show that： firstly, in the same season, the soil water pH covered by different types of vegetation decreases in the order of grassland 〉 mixed forest 〉 shrubs 〉 pine, and the soil base saturation decreases in the order of grassland 〉 mixed forest 〉 shrubs 〉 coniferous forest. Secondly, the concentrations of main basic ions in the soil are negatively correlated with the soil water content. The concentration of the basic ions in the soil is the highest in spring, the next in autumn, and the lowest in summer. Thirdly, the impacts of acid deposition on the soil covered by different types of vegetation are different and decrease in the order of coniferous forest 〉 shrubs 〉 mixed forest 〉 grassland.