赣南脐橙果园土壤有机质变化特征研究

以赣南脐橙18个县（市）果园为采样区，共采集了果园土壤农化样1405份和背景样229份，测定了土壤的有机质含量，并从果园土壤有机质的区域分布特征、有机质随土壤类型以及种植年限的变化特征进行统计分析。结果表明：不同种植区域果园土壤有机质含量分布存在较大差异，土壤农化样有机质含量变幅在1.01～47.58 g/kg之间，81％的果园土壤表现为有机质缺乏；有机质的含量与土壤本身的结构和特性紧密相关，紫色土有机质缺乏表现最明显；对不同种植年限果园，随园龄增加，在前10年内土壤有机质含量明显提高，之后稍有下降并趋于稳定。基于土壤有机质变化特征及对果园的现状调查，提出了提高果园土壤有机质的主要技术措施。

Assessments on soil organic matter of navel orange orchards in Ganzhou city, Jiangxi province

1405 soil samples from navel orange orchards and 229 natural background soil samples nearby the orchards were collected from eighteen counties in Ganzhou city, Jiangxi province. The distribution characteristics of soil organic matter in different county orchards, and variations in soil organic matter among different soil types and different orchard age were statistically analyzed. The results showed that the differences of soil organic matter contents in different counties were obvious, and the organic matter contents were between 1.01~47.58 g/kg, and the orchard soil with less than 15 g/kg of organic matter accounted for 81% of the total orchard soil samples. The soil organic matter contents varied with the soil types based on different soil structure and property, and the lowest content of organic matter occurred in purple soil. The soil organic matter content increased obviously during the first ten years after planting, and then slightly decreased. The technical measures to enhance soil organic matter were suggested based on the distribution characteristics of soil organic matter and orchard survey.