苦豆子种子害虫的斑块边缘效应  

Patch edge effect of seed pests of Sophora alopecuroides

作　　者：张大治[1] 吴光胜 陈良越 马志芳 ZHANG Da-Zhi;WU Guang-Sheng;CHEN Liang-Yue;MA Zhi-Fang(School of Life Science,Ningxia University,Yinchuan 750021,the Ningxia Hui Autonomous Region,China)

机构地区：[1]宁夏大学生命科学学院,银川750021

出　　处：《环境昆虫学报》2020年第4期895-902,共8页Journal of Environmental Entomology

基　　金：国家自然科学基金(31860619,31560611)。

摘　　要：边缘效应是生态学中最常见的一种现象,也是景观生态学理论探讨的热点之一。豆荚螟Etiella zinckenella是苦豆子种子的主要害虫。本实验以宁夏灵武市中东部的沙化区为实验样地,选择了一半径约为30 m的圆形斑块,按同心圆由中心向外每隔5 m从8个方位调查了苦豆子种子害虫的空间分布格局,分析了苦豆子种子害虫数量及其对豆荚、豆粒的危害率由斑块中心到边缘不同圈层的变化特征。结果表明:从斑块中心到边缘,苦豆子平均豆荚长度(51.16~53.88 mm,P>0.05)、豆粒数(3.72~4.45粒/荚,P>0.05)均无显著差异;豆荚螟数量呈逐渐增加的趋势(0.2602→0.7328个/荚,R 2=0.9008),受边缘效应影响差异显著(P<0.05),具有明显的边缘正效应,主要沿东南-西北方向呈梭形分布。不同方位的总豆荚、豆粒危害率差异显著(P<0.05),由中心向边缘总豆荚受害率(21.11%→53.29%)、总豆粒受害率(22.91%→36.34%)也呈渐增趋势,具有明显的边缘正效应。在东南方向上豆荚、豆粒的危害率(63.83%,41.82%)最高,其次是西北方向(47.87%,30.30%),东北方向最低(23.27%,16.24%)。Edge effect is a most common phenomenon in ecology and it is one of the research hotspots in landscape ecology.Etiella zinckenella is one of main seed pests of Sophora alopecuroides.A circular patch(2964.23 m 2)of S.alopecuroides was selected from experimental plot in mid-east in Lingwu City of Ningxia.Spatial distribution pattern of E.zinckenella larva was investigated from the center to margin of patch per 5 meters in eight directions.The density of E.zinckenella larva and the variance of its damage rates to beans and pods of different circle layers from center to margin of patch are analyzed.The results showed that the average pods lengths of S.alopecuroides were from 51.16 mm to 53.88 mm,and the numbers of seeds are from 3.72 to 4.45 in a pod from center to margin of patch.There are no significant differences in length of pods(P>0.05)and number of seeds(P>0.05)at different distances.The larva number of E.zinckenella per pod is increased significant(R 2=0.9008,P<0.05)from the center of the patch(0 m,0.2602)to the margin of the patch(25 m,0.7328)with apparent positive edge effect.The distribution of E.zinckenella larva in the patch is mainly along the southeast-northwest direction in a spindle shaped style.The damage rates of total pods and beans in different directions were significantly different(P<0.05):21.11%→53.29%in pods and 22.91%→36.34%in beans,which also shows positive edge effects.The damage rate of pods and beans are highest in the Southeast direction(63.83%,41.82%),followed by the northwest direction(47.87%,30.30%),and the northeast direction was the lowest(23.27%,16.24%).

关 键 词：边缘效应 斑块面积 苦豆子 豆荚螟 种子害虫 

分 类 号：Q968.1[生物学—昆虫学] S433[农业科学—农业昆虫与害虫防治]