摘要
边缘效应与溢出效应是近几年来生境管理研究的关键问题.为探讨这2种效应对麦蚜天敌种群动态及群落结构的影响,以及揭示农业景观中天敌的生物控害作用和探索及利用途径,本文设计5种不同的麦田生境界面,包括麦田-苜蓿草地、麦田-农田防护林,麦田-田埂、麦田-作物以及麦田-裸地.利用陷阱法、网捕法以及定点采集等方法调查5种不同生境界面中麦蚜天敌的丰富度和多度,并分析其种群及群落的边缘效应以及溢出效应.结果表明,非作物生境是多种麦蚜天敌的种群资源库,尤其是苜蓿草地、农田防护林以及田埂,这3类非作物生境在维持天敌种类和数量中发挥着重要的作用和功能.苜蓿草地储存大量的天敌资源如寄生蜂、瓢虫、食蚜蝇等,而且在生境界面上存在着明显的溢出效应.当麦田麦蚜爆发时,大量天敌从邻近的苜蓿生境区涌入麦田,实现对麦蚜有效的生物控害功能.农田防护林-麦田与田埂-麦田两种界面上麦蚜天敌如步甲与蜘蛛存在明显的边缘效应.然而,麦田-作物和麦田-裸地的两种界面上没有明显的边缘效应和溢出效应,作物和裸地这2种生境不能发挥维持天敌种群及群落的作用.通过分析边缘效应与溢出效应的尺度问题,结果显示,影响麦田天敌种群分布的尺度在30m左右,超过30m的区域边缘效应以及溢出效应不明显.这些研究结果可以为实现生物控害功能的农业景观格局规划与设计提供重要的理论基础,也可以为害虫种群控制提供新的思路和方法.
A majority of empirical tests have succeeded to support the hypothesis of edge effects and spillover effects. However, the two hypotheses tested in agro-ecosystems were rare. In order to discover edge effects and spillover effects on natural enemy＇s populations of wheat aphids, we designed 5 different habitat interfaces including wheat-alfalfa, wheat-tree land, wheat-range, wheat-crop and wheat-bare land in Northwest of China. The biological control of natural enemies for wheat aphids were analyzed which aims to conduct habitat management in agricultural landscapes. We studied edge effects and spillover effects of natural enemy＇s population and distribution through barber traps, net sweeping and clapper collection. Results showed that non-crop was important resource pool of natural enemies especially in alfalfa habitat, tree land and range habitat. Populations and communities of natural enemies in non-crop habitat played an important those role in biological control of wheat aphids. Communities of natural enemies （parasitoids and predators） in alfalfa were the same as those in wheat fields. In interface of alfalfa-wheat, spillover effects obviously exist. A majority of natural enemies （spiders and carabid beetle） immigrating from alfalfa habitat spread into wheat field and suppressed wheat aphids to a great extent. In interfaces of wheat-tree land and wheat-range, edge effects obviously exist. The biodiversity of natural enemies was higher in the interfaces than the inside of habitat. Hosts could be found in wheat habitat. Flowers, nectar and refuges could be found in non-crop habitat. Populations of natural enemies were larger in interface of wheat and non-crop than in other regions. However, crop habitat and bare land could play an important role in biological pest control of cereal aphids. The scale of edge effect was about 30 m below which natural enemies＇ populations were more abundant than those in other regions. All these results can be applied in agricultural landscape design which aims at biological control and provided important theoretical principles, and also supplied new ways and methods for pest population control.
出处
《中国科学：生命科学》
CSCD
北大核心
2012年第10期825-840,共16页
Scientia Sinica(Vitae)
基金
国家自然科学基金(批准号:31260429和31200321)资助项目
关键词
边缘效应
溢出效应
尺度
界面
麦田
生境管理
edge effects, spillover effects, scale, interfaces, wheat fields, habitat management
