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31.
Anthropogenic modification of the countryside has resulted in much of the landscape consisting of fragments of once continuous habitat. Increasing habitat connectivity at the landscape-scale has a vital role to play in the conservation of species restricted to such remnant patches, especially as species may attempt to track zones of habitat that satisfy their niche requirements as the climate changes. Conservation policies and management strategies frequently advocate corridor creation as one approach to restore connectivity and to facilitate species movements through the landscape. Here we examine the utility of hedgerows as corridors between woodland habitat patches using rigorous systematic review methodology. Systematic searching yielded 26 studies which satisfied the review inclusion criteria. The empirical evidence currently available is insufficient to evaluate the effectiveness of hedgerow corridors as a conservation tool to promote the population viability of woodland fauna. However, the studies did provide anecdotal evidence of positive local population effects and indicated that some species use hedgerows as movement conduits. More replicated and controlled field investigations or long-term monitoring are required in order to allow practitioners and policy makers to make better informed decisions about hedgerow corridor creation and preservation. The benefits of such corridors in regard to increasing habitat connectivity remain equivocal, and the role of corridors in mitigating the effects of climate change at the landscape-scale is even less well understood.  相似文献   
32.
We investigated the impacts of application of the sulfonylurea herbicide, metsulfuron-methyl, on soil and litter invertebrates in coastal vegetation where the weed Chrysanthemoides monilifera has invaded. We followed changes in litter invertebrates for 125 days following treatment to investigate direct toxic and indirect effects of treatment. Overall we found no effect of treatment on abundance, taxonomic richness or composition of litter invertebrates. In general, abundance and richness declined with time in both treated and untreated sites, suggesting that climatic factors were far more important in determining invertebrate communities than the effects of the treatment. Even changes in cover of vegetation as a result of death of the weed resulted in few measurable effects on invertebrates. It is concluded that metsulfuron-methyl had no impact on invertebrate communities up to 125 days following treatment.  相似文献   
33.
Indigenous soil macroinvertebrates (moth larvae, weevil larvae, earthworms) are cardinal agents of nutrient release from litter on sub-Antarctic Marion Island (47°S, 38°′E). Their populations are threatened through predation by introduced house mice, which do not prey on an introduced slug Deroceras panormitanum. A microcosm study was carried out to explore whether slugs affect rates of carbon and inorganic nutrient mineralisation from plant litter differently to an indigenous caterpillar (larva of a flightless moth Pringelophaga marioni). Caterpillars stimulated N, Ca, Mg and K mineralisation from plant litter two to five times more than slugs did, whereas the two invertebrate types stimulated C and P mineralisation to the same degree. Consequently, ratios of C:N and N:P released from the litter were different for slugs and caterpillars. Such differences might affect peat nutrient quality and ultimately the peat accumulation-decomposition balance, an important driver of ecological succession. This suggests that slugs cannot simply replace caterpillars without consequences for ecosystem structure and functioning on the island.  相似文献   
34.
海南岛尖峰岭灰蝶的区系与生态分布的研究*   总被引:1,自引:0,他引:1       下载免费PDF全文
在海南岛尖峰岭林区共采集到灰蝶103处,其中在热带山地雨林中采到81种,占尖峰岭灰蝶种数的78.64%;分布在东洋区84种,占尖峰岭灰蝶种数的81.55%。亚洲热带区域特有种40种,中国分布新记录17种,优势种群19种。  相似文献   
35.
海南岛尖峰岭热带林自然保护区的白蚁,已鉴定种名的有44种,这些白蚁除3种广布于热带区域外,都分布在东洋区,其中属海南特有的共26种,占尖峰岭白蚁和种群数的59.1%;待发表新种11种,占尖峰岭白蚁种群数的25%。热带半落叶季雨林中的白蚁最多,共36种。这是该被类型气温高的缘故。  相似文献   
36.
One hundred and fifty-four jarrah (Eucalyptus marginata) and 85 marri (Corymbia calophylla) trees were measured and assessed, and the numbers and sizes of hollows in these trees were determined by destructive sampling; 665 hollows were located and measured. The relationship between tree diameter and tree age was determined from counts of annual growth rings on 162 of these trees. Large trees and trees with moderately senescent crowns individually bear the most hollows. Although the number of hollows found in individual trees increased with tree diameter, the distribution of tree diameters in the forest is skewed and the large number of small trees with diameters between 40 and 80 cm contribute approximately 50% of all hollows in the jarrah forest. The distributions of entry size, and of hollow depth, are highly skewed, with small hollows occurring more frequently than large hollows. Although jarrah trees bear more hollows than marri trees and the distribution of entry sizes is similar for both tree species, the hollows in jarrah are significantly smaller than the hollows in marri. Most hollows are cylindrical in shape, vertically oriented and occur in dead wood in the tree crown. Relatively few hollows (14%) occur in the tree bole or at crown break. Counts of hollows made from ground level are inaccurate as estimates of the actual number of hollows in trees.  相似文献   
37.
湖南借母溪自然保护区两栖动物区系研究   总被引:1,自引:0,他引:1  
报道了借母溪自然保护区两栖动物资源和区系特征的调查结果。已知有2目8科25种。广布种5种,古北界种1种,东洋界19种。进而进行区系分析和多样性分析。  相似文献   
38.
云南小黑山省级自然保护区具有典型性、稀有性、多样性、脆弱性、自然性、完整性等自然属性特点;就保护区的生态、社会、经济效益对保护区的保护属性进行了评价;分析保护区的管理现状和存在的主要问题。综合评价结果,保护区的建设是一项生态效益巨大、社会效益显著的生态工程,对连接南北动、植物区系起着重要作用,在科研上具有重要价值。  相似文献   
39.
森林经营是实现森林可持续发展的根本途径,土壤动物是森林生态系统的重要组成部分,可对森林经营及其带来的变化及时做出反应。为了探讨土壤动物对森林经营措施的响应,归纳总结了森林经营理念的发展以及森林经营对土壤动物影响的文献资料。结果表明森林经营主要通过对地上结构和微环境的改变对地下土壤动物的群落组成、分解功能及生物指示功能等方面产生影响。在今后研究中应加强森林经营对土壤动物连续长期的动态影响研究,同时利用现代研究技术与方法深入探讨森林经营对土壤动物影响的机制研究。  相似文献   
40.
于2010年6~10月和2011年2~8月,对维西县野生哺乳动物进行了野外调查,调查地点包括塔城镇、攀天阁乡、白济汛乡、叶枝镇、巴迪乡、永春乡、维登乡、保和镇、康普乡等9个乡镇。共记录了55种哺乳动物,隶属8目、21科、44属。其中东洋界种类占全部哺乳动物种数的67.27%,古北种占12.73%,广布种占20.00%。其中属国家I级保护5种,国家Ⅱ级保护10种,省级保护2种,列入CITTES附录的20种。  相似文献   
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