荒漠地区柠条种实害虫对寄主斑块质量与结构的反应
he Response of Seed Pests of Caragana Shrubs to Habitat Area and Fragmentation in Desert Landscape, Ningxia
一般认为,景观中斑块质量、斑块面积和破碎化对物种丰富度、分布格局和种群动态有重要的影响。在西北多数荒漠地区,由于受环境、地形地貌以及人为补播等因素的影响,天然柠条林和人工柠条林地交错排列,形成点、片、带状等大小不等的斑块性分布,表现为典型的破碎化斑块格局生境特征。本文以宁夏中东部荒漠区为景观背景,在大、小两种尺度下,选择人工固沙林地、流动风积沙地和沙壤土质丘陵地三种生境类型共18块天然或人工种植的柠条林斑块,研究了柠条豆象Kytorhinus immixtus、豆荚螟Etiella zinckenella和柠条种子小蜂Bruchophagu neoaraganae三种柠条种实害虫对寄主植物斑块质量、生境面积和破碎化格局的反应。结果显示,三种柠条种实害虫对寄主植物的为害率与斑块质量、斑块格局及物种迁移能力有关。对斑块质量的反应受到斑块尺度大小的影响,在大尺度斑块格局中,主要反应于大的生境类型的不同而为害率差异显著(F0.05(2,15)=4.79>3.68,P<0.05),以人工次生林地为害率最高,其次为沙壤土质坡地,流动风积沙地相对较低。在小尺度斑块格局中,为害率差异不显著(F0.05(2,15)=1.88<3.68,P>0.05)。柠条种实害虫数量的发生与寄主植物斑块的面积、破碎化程度存在着一定的相关性,斑块面积减少、生境破碎化程度增加对移动能力较强的豆荚螟(R=0.3646)能够降低其为害率,而对移动能力弱的柠条豆象(R=0.1599)、柠条种子小蜂(R=0.1934)则相关性不强。斑块边缘效应强度及景观斑块周边资源互补对种群密度会产生积极的影响。
here is increasing empirical evidence that the quality of habitat patches, habitat area and fragmentation play an important role in determining species distribution patterns and in regulating spatial dynamics. In this study, using desert landscape fragments within the desert steppe of Mid-Eastern of Ningxia, China, we experimentally investigated the effects of habitat area, habitat fragmentation, and habitat quality on the response of seed pests (Kytorhinus immixtus, Etiella zinckenella and Bruchophagu neoaraganae) of Caragana shrubs. At coarse scale and fine scale patches pattern, 18 patches of Caragana shrub were surveyed that they were belong to three types plots such as the artificial forest land, the flowing desert sand land and the sandy loam hill land. Our results showed that the damage ratio of E. zinckenella to host plant's pods and seeds were highest, B. neoaraganae were second, and K. immixtus were lowest. Damage of seed pests on host plants were significantly influenced by patch quality. At coarse scale, the total damage ratio of three species were significant difference among plots (F0.05 (2, 15) = 4.79> 3.68, P <0.05), but not significant among patches (F0.05 (2, 15) = 1.88 <3.68, P> 0.05) at fine scale patches pattern. The damage ratio in the artificial fixing desert was higher than the flowing desert sand and the sandy hills. Patch area and fragmentation were significantly associated with pest's population densities. The habitat fragmentation can reduce the damage ratio, but at sometimes were effected with the patch quality and the abilities of migration of seed pests. The damage ratio of E. zinckenella was significantly affected by habitat area and habitat fragmentation(R=0.3646), while the K. immixtus and B. neoaraganae were not obvious with habitat area and habitat fragmentation(R=0.1599,R=0.1934). The edge effects of patch and surrounding patches of landscape have a positive effect on population densities of seed pests.
范玉婷、贺达汉、张大治
植物保护农业科学研究环境科学基础理论
荒漠景观生境破碎化斑块质量斑块格局种实害虫柠条
desert landscapehabitat fragmentationpatch qualitypatch patternseed pestsCaragana
范玉婷,贺达汉,张大治.荒漠地区柠条种实害虫对寄主斑块质量与结构的反应[EB/OL].(2010-12-31)[2025-08-23].http://www.paper.edu.cn/releasepaper/content/201012-1492.点此复制
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