不同环沟管理方式对成龄龙眼园土壤理化性质及树体水分的影响

Effects of different circular ditch methods on soil physical and chemical properties in mature longan plantation

【目的】研究以环沟为基础的不同土壤管理方式对龙眼树体水分及土壤理化性状的影响,探索适宜的栽培模式,为龙眼的栽植提供理论依据。【方法】在成龄龙眼园中设环沟养殖蚯蚓、环沟覆白膜、环沟覆黑膜、环沟无覆膜处理,以无环沟无覆膜处理作对照,测定土壤温度、含水量、有机质含量和树体叶片相对含水量、枝条水势等指标。【结果】环沟覆黑膜、环沟覆白膜、环沟养殖蚯蚓及环沟无膜处理均能提高土壤温度,增加土壤含水量,提高土壤有机质;其中环沟覆白膜处理能显著增加土壤温度,相比对照处理各土层平均提高1.92℃;环沟覆膜养殖蚯蚓处理能显著增加土壤有机质及含水量,和对照处理相比,有机质提高8.31g/kg,含水量提高1.1%;环沟养殖蚯蚓的叶片相对含水量显著高于对照(P<0.05,下同),但枝条水势与对照处理差异不显著(P>0.05);其他处理的叶片相对含水量及枝条水势均显著低于对照处理。【结论】环沟蚯蚓能增加土壤水分和有机质含量,提高龙眼叶片相对含水量和枝条水势,可在生产上进行应用;龙眼园夏季不宜采取覆膜措施。

[Objective]Effects of different circular ditch methods on soil physical and chemical properties in mature longan plantation were studied to explore the optimal cuhivation mode and provide theoretical references for longan cultivation. [Method]In mature longan plantation, five treatments viz., circular ditch and earthworm, circular ditch and black film, circular ditch and white film, circular ditch without film and no circular ditch no film （CK） were arranged. Soil temperature, soil water content, soil organic matter, leaf relative water content and water potential of twigs were determined under the treatments. [ Result ]Circular ditch and earthworm, circular ditch and black film, circular ditch and white film and circular ditch without film all improved soil temperature, soil water content and soil organic matter. Circular ditch and white film significantly increased average soil temperature of different soil layer, which was 1.92 ~C higher than that of the control. Circular ditch and earthworm significantly improved soil water content and soil organic matter. Compared with the control, soil organic matter rose by 8.31 g/kg and soil water content by 1.1%. Under circular ditch and earthworm treat- ment, leaf relative water content was significantly higher than that of the control, while water potential of twigs showed no evident difference. Leaf relative water content and water potential of twigs under other treatments were significantly lower than those of the control. [ Conclusion ]Circular ditch and earthworm can effectively improve soil water content, soil organic matter, leaf relative water content and water potential of twigs, hence it can be used in production, however film mulching is unsuitable for summer longan plantation.