不同灌溉模式对广西蔗田大型土壤动物群落结构的影响

摘要

To explore effects of irrigation method on community structure of soil macro?animals, a survey was carried out in May-November 2015 of community structures of the soil macro?fauna and soil physico?chemical properties of the sugar?cane fields under water?saving irrigation experiment in Jiangzhou District, Chongzuo of Guangxi. The water?saving irrigation experiment was designed to have 5 irrigation methods, i. e. imbedded drip irrigation, surface drip irrigation, tube irriga?tion, sprinkler irrigation and micro?sprinkling irrigation, and a blank ( no irrigation) added as control. In the plots of the six treatments, a total of 1180 individuals of soil macro?fauna were collected, belonging to two phyla, 10 classes and 18 orders. Hymenoptera ( Formicidae) was the dominant group, accounting for 71. 44% of the total, and Araneae, Isoptera ( Termitidae) , Dermaptera, Orthoptera, Coleoptera, Blattaria, Hemiptera, and Isopoda were the common ones. The treat?ments did not vary much in number of groups, but all the treatments with irrigation, especially the treatments of imbededed drop irrigation and sprinkling irrigation, were obviously higher than control in density of soil macro?fauna, Shannon?Wiener diversity index ( H) , Pielou evenness index ( E) , and Margalef abundance index ( D) , but lower in Simpson dominance index ( C ) . Moreover the treatments also varied significantly in soil physicochemical property. The treatments with irrigation were all, especially the treatments of imbededed drop irrigation and sprinkling irrigation, higher than control in soil water content, organic matter, available nitrogen, available phosphorus and available potassium. Obviously, water?sav?ing irrigations enhance or improve soil water storage capacity, soil nutrient supply and micro?environment of the sugarcane fields, and alter community structure of the soil macro?fauna, mainly in density and diversity. Imbedded drip irrigation and sprinkler irrigation works the most prominently.%为了探讨不同灌溉模式对大型土壤动物群落结构的影响,在广西崇左市江州区糖料蔗节水灌溉试验区设置地埋滴灌、地表滴灌、管灌、喷灌、微喷5种灌溉处理以及无灌溉空白对照共6个样地,于2015年5—11月对大型土壤动物群落及土壤理化性质进行调查.共捕获大型土壤动物1180只,隶属于2门10纲18目,优势类群为膜翅目(蚁科),占总数的71.44%;常见类群为蜘蛛目、等翅目(白蚁科)、革翅目、直翅目、鞘翅目、蜚蠊目、半翅目和等足目.不同灌溉模式各样地大型土壤动物类群数差异不显著.灌溉处理样地大型土壤动物密度、Shannon?Wiener多样性指数(H)、Pielou均匀度指数(E)和Margalef丰富度指数(D)均优于无灌溉样地,Simpson优势度指数(C)则相反,并且地埋滴灌、喷灌样地与无灌溉样地间上述指标均差异显著.不同灌溉模式对蔗田土壤理化性质产生显著影响,地埋滴灌、地表滴灌、管灌、喷灌和微喷样地土壤含水率、有机质含量、速效氮含量、速效磷含量及速效钾含量均高于无灌溉样地,且地埋滴灌与喷灌样地上述指标值较高.节水灌溉增强了土壤的储水能力,提高了土壤的营养条件,改善了蔗田土壤的微环境.大型土壤动物群落结构在不同灌溉模式下变化显著,主要表现在大型土壤动物密度与多样性增加,地埋滴灌和喷灌方式样地表现尤为突出.