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141.
带织蛾属在中国已记载9种,均为Meyrick在1894年至1936年期间发表,其中Periacma conophanta Meyrick已移至斑织蛾属,本文记述中国该属5新种和1新记录。 相似文献
142.
A change in the vegetation of UK moorland from Calluna vulgaris-dominated heath to Molinia caerulea- or Nardus stricta-dominated grassland is frequently deemed undesirable on economic and biodiversity grounds. Moorland vegetation restoration is an increasingly practiced management option. However there has been little research on the effectiveness of such management for aiding the restoration of other aspects of moorland biodiversity such as associated insect populations.We sampled Hemiptera and Lepidoptera assemblages from restored, degraded and C. vulgaris-dominated (target) moorland at eight restoration sites in England and Scotland. Vegetation assemblages and additional environmental variables were sampled at the same locations.Vegetation restoration aided the reassembly of moorland insects to a variable extent. Hemiptera restoration success was greatest at mechanically restored sites dominated by C. vulgaris. In addition to treatment, latitude best explained variation in the Hemiptera assemblage. A range of plant species, all either dwarf shrubs or graminoids, acted as further determinants. Lepidoptera restoration success was correlated most closely with the success of restoring the full diversity of the vegetation assemblage and was highest at sites restored by grazing control.The results demonstrate that vegetation restoration brings wider biodiversity benefits and that the form these take may depend on the restoration method used and consequent characteristics of the resultant vegetation assemblage. 相似文献
143.
从抗虫种质资源抗虫鉴定、抗虫机理及芸薹属作物抗虫基因工程等方面综述了近20年来芸薹属植物抗 鳞翅目昆虫的研究成果。 相似文献
144.
Commercial selective logging is a major cause of habitat disturbance in Southeast Asian rainforests, yet despite much research there is little consensus on impacts of disturbance on biodiversity. There is also little consensus on the most appropriate methods for sampling tropical species, making it difficult to draw general conclusions from published studies. For example, many studies have used butterflies to assess impacts of selective logging but sampling has usually been conducted at ground level and the canopy fauna has often been ignored. In this study, we investigate the importance of sampling in the canopy by using fruit-baited traps to investigate impacts of selective logging on Nymphalid butterflies in primary forest and forest selectively logged 15 years previously in Sabah (Malaysian Borneo). Analysing combined data from canopy (≈25 m above ground level) and ground-level traps showed significantly lower diversity in selectively logged forest. However, this difference was not observed when data from only ground traps were analysed. Primary forest supported a butterfly assemblage comprising species with more restricted geographical ranges, and thus higher conservation value, compared with selectively logged forest. This result was observed regardless of whether or not canopy data were included in this analysis. We conclude that sampling in the canopy is critical when producing species inventories, but of little importance when determining the impacts of selective logging on restricted-range species. 相似文献
145.
Community level analyses of species-environment relationships can provide critical information for conservation planners. A comprehensive analysis of the factors that influence species distributions should include variables measured at multiple scales because species-environment relationships are known to vary with the scale of observation. The pitch pine-scrub oak (Pinus rigida-Quercus ilicifolia) communities, or pine barrens, of the northeastern USA are severely threatened by development and fire suppression. They also provide critical habitat for many species of rare moths. We used partial canonical correspondence analysis to assess the relative effects of three levels of environmental variables (plot, patch, and landscape) on the distribution and abundance of 10 species of rare moths in a pine barrens community in southeastern Massachusetts, USA. We also used a set of spatial variables to quantify and partial out the effects of spatial autocorrelation of species composition among sampling locations. All three levels of environmental factors combined, independent of spatial factors, accounted for virtually half (48.4%) of the total variation in the moth community. Sequential partitioning of the variance explained by each level of environmental factors indicated that landscape level factors explained more than twice as much variance as plot and patch level factors. Another environmental model that included only landscape level variables explained 53% of the total variation in the moth community. Patch density and percentage of the landscape comprised of open and sparse canopy, scrub oak habitats were the most significant variables. These results suggest that the presence of scrub oak habitat within relatively large, heterogeneous landscape mosaics may be more important for the maintenance of many rare pine barrens associated moth populations than plot or patch level characteristics. 相似文献
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148.
鳞翅目昆虫性信息素合成的分子机制研究进展 总被引:1,自引:0,他引:1
信息素(pheromone)对昆虫的繁殖和种间隔离有重要作用。对鳞翅目昆虫雌性信息素的生物合成途径、性信息素成分比例调节、信息素生物合成激活肽(pheromone biosynthesis activating neuropeptide,PBAN)在性信息素合成中的调节作用,以及鳞翅目昆虫性信息素合成相关脱饱和酶的分类和作用等研究进展进行了综述。从NCBI上搜索了鳞翅目昆虫现有的脱饱和酶基因,利用DNAstar软件对各种脱饱和酶基因进行了系统发育树构建和分析,发现脱饱和酶基因的聚类不是由物种决定的,而是由其自身的复制需要和脱饱和酶的作用功能决定的。 相似文献
149.
本文从形态结构、化石、地质历史及分子钟等方面,对蝴蝶进化与起源的研究现状进行了总结,认为不同蝴蝶类群的进化没有十分清晰的脉络,一般认为蝴蝶的3个总科中广蝶总科最为原始,弄蝶总科次之,凤蝶总科则最为进化;蝴蝶起源于何时仍然是备受关注且有待探索的科学命题。 相似文献
150.
首次报道了中国西藏地区肃蛱蝶属一新纪录种:竹肃蛱蝶 Sumalia zulema (Doubleday & Hewitson),简要描述了该种的形态特征,并提供了雄虫成虫图片和雄性外生殖器图. 相似文献