摘要
以宁夏中东部荒漠区为景观背景,选择人工固沙次生林地、流动风积沙地和沙壤土质丘陵地3种生境类型共18块天然或人工种植的柠条林斑块,研究了柠条豆象、豆荚螟和柠条种子小蜂3种柠条种实害虫对寄主植物斑块质量、斑块面积和空间格局的反应.结果显示:3种柠条种实害虫对寄主植物的为害率与斑块质量、斑块格局和昆虫自身迁移能力有关.对斑块质量的反应受到斑块尺度大小的影响,在不同的生境类型间,种实害虫的为害率差异显著(P<0.05),以人工固沙次生林地的为害率最高,其次为沙壤土质丘陵地,流动风积沙地相对较低.在小斑块格局中,柠条种实害虫数量的发生与寄主植物斑块的面积、破碎化程度存在一定的相关性,斑块面积减少、生境破碎化程度增加能够降低移动能力较强的豆荚螟(r=0.365)的为害率,而对移动能力较弱的柠条豆象(r=0.160)、柠条种子小蜂(r=0.193)则没有明显影响.斑块边缘效应强度和景观斑块周边资源互补对种群密度具有正相关的影响.
Taking the desert landscape in mid-eastern Ningxia of Northeast China as the background,eighteen patches of Caragana shrub lands（natural or manned） with the habitat types of manually-fixed sandy land,mobile sandy land,and silty-loam downland were selected as study sites to investigate the responses of three Caragana seed pest species（Kytorhinus immixtus,Etiella zinckenella,and Bruchophagus neocaraganae） to the host plant patch quality,patch area,and patch spatial pattern.The damaged rate of host plant by the pests had close relations to the patch quality,patch pattern,and the transferring capability of the pests.The responses of the pests to patch quality were affected by patch scale,and among the three habitat types,manually-fixed sandy land had the highest damaged rate,followed by mobile sandy land,and silty-loam downland,with significant differences among them（P0.05）.In small scale patch pattern,there existed definite correlations between the pest number and the patch area and its fragmentation degree.The decrease of patch area and the increase of the fragmentation degree reduced the damage rate of high transferring capability Etiella zinckenella（r=0.365）,but had less effects on low transferring capability K.immixtus（r=0.160） and B.neocaraganae（r=0.193）.The strength of patch edge effect and the mutual complement of the resources around patches had positive effects on the population density of the pests.
出处
《应用生态学报》
CAS
CSCD
北大核心
2011年第7期1871-1877,共7页
Chinese Journal of Applied Ecology
基金
国家自然科学基金项目(30760045)
宁夏自然科学基金项目(NZ0707
NZ0926)资助
关键词
荒漠景观
生境破碎化
斑块质量
斑块格局
种实害虫
柠条
desert landscape
habitat fragmentation
patch quality
patch pattern
seed pests
Caragana
