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海南省方头甲属种类记述(鞘翅目:方头甲科) 总被引:1,自引:0,他引:1
方头甲是一类重要的捕食性天敌,对盾蚧类害虫的生物防治有一定应用前景,该文简要记述了海南省产方头甲属种类共8种,并列出分种检索表。 相似文献
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东北地区危害农业、林业的鞘翅目昆虫多样性的研究(Ⅳ) 总被引:3,自引:0,他引:3
论述了东北地区危害农业、林业的鞘翅目昆虫3科,取叶甲科、肖叶甲科、铁甲科、共63种。作者对这种种类的分布及其取食特性的详细的描述,以期为广大农业、林业及植物保护工作者进行害虫防治提供科学依据。 相似文献
74.
简要介绍了新疆拟步Jia调查研究历史,记述了8族12属30种(亚种),其中1新种:三齿漠潜JiaMelamesthes(mongolesthes)tridentatussp.nov;1中国新纪录,蒙西长足JiaAdesmia(adesmia)anomaledejeaniGebler。 相似文献
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- Human activities are an increasing threat to Neotropical freshwater ecosystems, with the potential extinction of thousands of aquatic species. Despite this, knowledge about the effectiveness of protected area networks in protecting aquatic insects in this biogeographical region is very limited.
- Cuba supports the highest diversity of aquatic insects in the Antilles, with a large number of endemics.
- A gap analysis was conducted to assess the effectiveness of the National System of Protected Areas of Cuba (NSPAC) in the conservation of Cuban diving beetles (family Dytiscidae). This involved considering the areas with the highest potential species richness, estimated by using species distribution models with three different approaches (MaxEnt, Random Forest and Support Vector Machine), and the known localities of endemic species.
- The highest potential species richness of Dytiscidae in Cuba is predicted to occur in the low–medium altitude of the eastern mountain areas. Although most of these areas occur inside the NSPAC, several areas of potential high species richness are currently unprotected. It is recommended that sampling programmes are carried out in areas with high predicted species richness to validate the species distribution models.
- The distribution of three Cuban endemic species (Copelatus barbouri, Desmopachria glabella and Celina cubensis) lies completely outside of the NSPAC. Despite their conservation interest as threatened endemic species, they are currently unprotected.
- To improve the conservation of freshwater biodiversity in Cuba it is recommended that (i) the NSPAC network is extended to protect areas supporting endemic species and those with the highest potential species richness that are currently unprotected, and (ii) a whole-catchment management approach, specifically to maintain natural flows, should be adopted, especially in the mountainous areas of eastern Cuba.
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The aim of this study was to evaluate how future harvesting of spruce low stumps as a renewable energy source, might influence the saproxylic (wood living) beetle fauna. Species richness, abundance and assemblages of saproxylic beetles were compared on low stumps, high stumps and logs of spruce on 10 clear-cuts in northern Sweden. The sampling was conducted with emergence traps and a total of 929 individuals and 120 species were collected. No significant differences in beetle abundance or species richness were detected between substrate types. However, there were clear differences in assemblage composition between all substrate types. Our results suggest that low stumps created at final felling support as many species and individuals per volume dead wood as other dead wood substrates and that they are therefore overlooked as substrates for wood living organisms. Consequently, harvesting of low stumps might have negative effects on the diversity of saproxylic beetles, as up to 80% of the dead wood remaining on clear-cuts is in the form of low stumps. Future studies should evaluate if compensatory measures can be performed to minimize negative impacts. 相似文献
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Impact of the goldspotted oak borer,Agrilus auroguttatus,on the health of coast live oak before and after treatment with two systemic insecticides 下载免费PDF全文
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《Scandinavian Journal of Forest Research》2012,27(5):403-416
Abstract This study evaluates how the placement and the different possible outcomes of a spruce retention tree affected species richness and assemblages of spruce-associated saproxylic beetles. In a field experiment in the boreal zone of central Norway, high stumps were created and compared with residual wood pieces (i.e. top boles with branches), in clear-cuts versus in forest edges. Flight interception traps were mounted close to the substrate. The results were analysed using rarefaction techniques, ordination (DCA) and anova. It was found that the placement of retention trees of spruce does matter: beetle assemblages were significantly different in stumps in the four treatments. For all species pooled, the species richness was higher in stumps in clear-cuts than in stumps or boles in the forest edge. Four red-listed species were more abundant near stumps than boles, and two red-listed species were more abundant in clear-cuts than forest edge. To cater for the variety of habitat preferences among forest beetles in managed forest, managers should leave both standing spruce trees (many of which will end up as windthrown, downed boles) and some high stumps (to secure some upright dead wood), in both exposed clear-cut and semi-shaded forest edge. 相似文献
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