Habitat fragmentation alters predator satiation of acorns  

作　　者：Xin Tong Yu-Xuan Zhang Rong Wang Moshe Inbar Xiao-Yong Chen 

机构地区：[1]School of Ecological and Environmental Sciences,East China Normal University,Dongchuan Road 500,Shanghai 200241,China [2]Department of Evolutionary and Environmental Biology,University of Haifa,199 Aba Khoushy Ave.,Mount Carmel,Haifa 31905,Israel

出　　处：《Journal of Plant Ecology》2017年第1期67-73,共7页植物生态学报（英文版）

基　　金：National Natural Science Foundation of China(31361123001);National Science Foundation(DEB-1342751 and DEB-1342757).

摘　　要：Aims Acorn weevils(Curculio spp.),endoparasitic granivorous insects,impede recruitment of fagaceous trees,and in turn affect community structure and ecosystem functioning.Previous studies have made considerable progress in elucidating local factors that contribute to seed predation by acorn weevils,but it is still not clear how habitat configurations interplay with local factors in influencing Curculio predation.In this study,we assessed the roles of crop size,landscape configurations(area and isolation)and their interactions on the predation rate of seeds by acorn weevils.Methods We studied acorn weevils feeding on the seeds of Castanopsis sclerophylla(Fagaceae)on two peninsulas and nine islands with varying areas and isolation levels in the Thousand-island Lake in Chun’an County,Zhejiang Province of China.Overall,crop size was estimated for 130 trees and predation status was assessed for 26207 seeds from these trees during two years.Generalized linear mixed models were performed to clarify how island area and isolation interplayed with crop size to determine predation rate on a single tree.Important Findings A negative relationship was detected between crop size and seed predation rate,indicating predator satiation at the tree level.This suggests that acorn weevils tend to stay sedentary once they have arrived at a suitable habitat.Habitat fragmentation had significant effects on seed predation such that predation rate was higher on larger,less isolated islands.Furthermore,the relationship between crop size and predation rate was significantly changed by both island area and isolation.This finding highlighted that the effects of habitat isolation might be overlooked relative to those of habitat loss.

关 键 词：Castanopsis sclerophylla CURCULIO ISOLATION limited dispersal predator satiation 

分 类 号：F42[经济管理—产业经济]