重庆三峡库区柑桔园土壤酸性转化原因初探

Preliminary Research on Acidic Transformation of Citrus Orchard Soil pH in Three Gorges Region of Chongqing

过去,重庆三峡库区柑桔园土壤pH值多呈中性偏碱。近年来,对库区462个桔园的连续监测表明,老柑桔园土壤pH值中性偏碱的占53%;2003年以来新建柑桔园pH值呈酸性的占75%,表明三峡库区柑桔园土壤pH值整体向酸性转变;土壤pH值6.5以下呈酸性的柑桔园占送检总数的61%;土壤酸碱度由过去中性偏碱为主转为酸性为主,酸性转变现象明显。大多数柑桔园采用过去常规的针对中性偏碱土壤的施肥管理方法,加剧了柑桔园酸化的程度。本研究为制订针对三峡库区新出现的柑桔园土壤偏酸的施肥管理技术措施提供了研究基础。

The soil pH values of citrus orchards in Three Gorges Region of Chongqing were usually neutral to slightly alkaline in the past. Continuous monitoring in 462 citrus orchards in reeent years showed that 53% of the old orchards were still alkaline. However, 75% of the new orchards created after 2003 were acidic. Therefore, new orchards were the main contributor m the changed soil pH in Three Gorges Region of Chongqing. Among all tested samples, 61% of the orchards were ≤6. 5 in their soil pH. The traditional fertilizer application practice for neutral to slightly alkaline soils.would intensify the decrease trend of soil pH values. This study suggested a need for changing the fertilizer application tradition in citrus orchards in the Three Gorges Region of Chongqing.