区域农田景观格局对麦田天敌瓢虫群落的影响

Effects of regional agricultural landscape pattern on the community of ladybeetles in wheat fields

【目的】明确农田景观格局对麦田天敌瓢虫种群的影响,为开展区域性害虫生态调控提供理论依据。【方法】以山东省22个县市区域的小麦种植区为研究对象,基于遥感影像与土地覆盖分类数据以及田间调查的瓢虫种群数据,计算景观格局指数,使用负二项分布的广义线性模型从农田景观、非作物生境景观和区域景观3个方面分析区域农田景观格局对麦田天敌瓢虫群落的影响。【结果】麦田瓢虫种群数量与草地的平均斑块面积(mean patch area,AREA_MN)和面积加权平均斑块分维数(area-weighted mean patch fractal dimension,FRAC_AM)、区域景观的斑块丰富度密度(patch richness density,PRD)呈正相关,与非作物生境的面积加权平均几何最邻近距离(areaweighted mean Euclidean nearest neighbor distance,ENN_AM)呈负相关。草地、聚集的非作物生境以及多样性的区域景观有利于天敌瓢虫种群数量的增加。使用草地的平均斑块面积和非作物生境的面积加权平均几何最邻近距离可以预测瓢虫的发生量。【结论】作为非作物生境的草地、非作物生境的空间分布及区域景观的多样性是影响麦田天敌瓢虫发生的重要因素。

[ Aim ] To clarify the effects of agricultural landscape pattern on ladybeetle community in wheat fields, so as to provide theoretical proofs for ecological regulation and management of insect pests. [ Methods ] Based on the remote sensing data, land cover classification and the survey data of ladybeetle abundance in wheat fields in 22 counties and cities in Shandong, the planting region of wheat was taken as a typical example, the landscape pattern metrics were calculated, and the effects of landscape pattern of farmland, non-crop habitat and regional agricultural landscape on ladybeetle abundance were analyzed using negative binomial generalized linear model. [ Results ] The ladybeetle abundance was positively correlated with mean patch area （AREA_MN） and area-weighted mean patch fractal dimension （FRAC_AM） of grassland and patch richness density （PRD） of regional landscape, and was negatively correlated with area-weighted mean Euclidean nearest neighbor distance （ENN_ AM ） of non-crop habitat. Grassland, clustered non-crop habitats and diverse regional landscapes benefited ladybeetle abundance. AREA_MN of grassland and ENN_AM of non-crop habitat could best predict ladybeetle occurrence.