中文摘要：

基于广东省第二次土壤普查（20世纪80年代）以及2002—2007年广东省土壤pH数据,对期间土壤pH的时空变化进行了研究.结果表明：研究期间,广东省土壤pH空间分布格局基本一致;除珠江三角洲和清远、韶关部分地区土壤为弱碱性外,其他地区土壤以酸性为主;土壤pH变化整体表现为酸化,土壤pH平均值由5.70降至5.44.除潮土pH变化以增大为主外,其他土壤类型的pH均呈降低趋势,以赤红壤、水稻土和红壤pH的降幅尤为严重,石灰土pH值的降低趋势和降低面积比例均最明显.广东省土壤酸化主要受土壤本身特性和酸雨等自然因素以及不合理施肥和城市化等人为因素的影响;另外,由于工业化和矿山开发,还导致局部地区土壤pH值有所上升.

英文摘要：

Based on the 1980s＇ soil inventory data and the 2002-2007 soil pH data of Guangdong Province,the spatiotemporal variation of soil pH in the Province in past 30 years was studied.In the study period,the spatial distribution pattern of soil pH in the Province had less change（mainly acidic）,except that in Pearl River Delta and parts of Qingyuan and Shaoguan（weak alkaline）.The overall variation of soil pH was represented as acidification,with the average pH value changed from 5.70 to 5.44.Among the soil types in the Province,alluvial soil had an increased pH,lateritic red soil,paddy soil,and red soil had a large decrement of pH value,and lime soil was most obvious in the decrease of pH value and its area percentage.The soil acidification was mainly induced by soil characteristics,some natural factors such as acid rain,and human factors such as unreasonable fertilization and urbanization.In addition,industrialization and mining increased the soil pH in some areas.