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国内外茶叶产业发展情况分析研究   总被引:1,自引:0,他引:1       下载免费PDF全文
对国内外茶叶产业的茶园种植面积、茶叶年产量、消费量、进出口量以及国内茶类结构进行了分析研究。结果表明:世界茶叶的种植面积和产量呈增长趋势,茶叶年消费量增加,茶叶产业规模继续扩张;国内茶叶产业受市场需求变化影响,茶叶产品结构继续调整,绿茶依然保持市场主导地位,红茶、黑茶仍是消费的热点,黄茶近两年产量增加的趋势较大,其他茶类平稳发展。  相似文献   
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魏晔 《林产工业》2020,57(4):93-96
定制家具已经成为追求个性化和私密家居环境者的一个方向,但其多变性较强,在工业化生产过程中很难实现“无缝式”衔接,从而导致部分家装业定制家具的设计方案与家具产品之间产生差异。介绍了家装业定制家具的主要特征,论述了计算机集成制造家具的基本模式,具体分析了家装业定制家具设计与计算机集成制造系统中的衔接问题,有针对性地提出优化家具设计与计算机制造系统衔接的三项措施。  相似文献   
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农村养老问题关乎乡村全面振兴和新型城镇化进程。基于实地调研和访谈,以山东省淄博市Y村幸福院为例,对这一模式的运作过程、影响因素、存在问题以及优化路径进行了系统分析。调研发现,Y村幸福院存在资金短缺,参与主体互助意识不强,互助服务单一化,管理存在漏洞,运行效率不高等现实问题。为进一步推进该养老模式,政府应加大财政支持力度,为农村幸福院的运行提供物质基础;加强对互助养老模式的宣传力度,营造互助和谐的养老氛围;培养专业的养老服务队伍,优化养老服务体系;创新管理方式,打造特色管理团队。  相似文献   
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In common with other farmland species, hares (Lepus spp.) are in widespread decline in agricultural landscapes due to agricultural intensification and habitat loss. We examined the importance of habitat heterogeneity to the Irish hare (Lepus timidus hibernicus) in a pastoral landscape. We used radio-tracking during nocturnal active and diurnal inactive periods throughout one year. In autumn, winter and spring, hares occupied a heterogeneous combination of improved grassland, providing food, and Juncus-dominated rough pasture, providing refuge. In summer, hares significantly increased their use of improved grassland. This homogeneous habitat can fulfil the discrete and varied resource requirements of hares for feeding and shelter at certain times of year. However, improved grassland may be a risky habitat for hares as silage harvesting occurs during their peak birthing period of late spring and early summer. We therefore posit the existence of a putative ecological trap inherent to a homogeneous habitat of perceived high value that satisfies the hares’ habitat requirements but which presents risks at a critical time of year. To test this hypothesis in relation to hare populations, work is required to provide data on differential leveret mortality between habitat types.  相似文献   
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This study examines the behavioral ecology of a chimpanzee population on Rubondo Island in Lake Victoria, Tanzania, over 40 years after chimpanzees were first introduced to the island from captivity. Despite little pre-release habitat assessment, rehabilitation, or post-release monitoring, these chimpanzees are one of the only released populations to survive over decades without provisioning. We surveyed habitat structure and plant composition to gain insights into ecological features that have supported this self-sufficient chimpanzee population for over 40 years. We also examined possible ecological sources of chimpanzee ranging patterns on the island. We surveyed woody plant composition, and quantified densities of species producing large fleshy fruits and confirmed chimpanzee fruit foods across three chimpanzee ranging areas, each separated by several kilometers. We used non-metric multidimensional scaling (NMS) ordination to compare community-level patterns of plant composition across regions. The densities of trees and lianas producing fleshy fruits were high in comparison with similar measures at endemic chimpanzee study sites. There were major differences in the composition of tree species, including species of chimpanzee fruit foods, across the three regions. In contrast, liana species composition was similar across regions, and was characterized by a few super-abundant species, including one chimpanzee fallback food. The wide-ranging patterns of chimpanzees do not appear to be influenced by localized tree fruiting patterns, but may be facilitated by the wide-spread distribution of an important fallback food. In comparison with other endemic and release sites, the relatively low ecological population density of chimpanzees, the high density of both trees and lianas producing large fleshy fruits and the presence of a high-quality, widely-distributed fallback food are factors that likely contributed to the success of Rubondo chimpanzees in reverting to natural foraging behaviors after their release.  相似文献   
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The successful introduction of captive bred takhi or Przewalski’s horse, Equus ferus przewalskii, into Mongolia in the 1990s is a good example of the benefits of ex situ conservation and one of the few examples of the recovery of an animal after it became extinct in the wild. This is also particularly interesting because virtually nothing was known about how takhi lived before they died out, and the introductions have enabled us to study how they have settled, and their ecology and behaviour within their former natural range. In this paper, we describe the movement, home range size and shape, and habitat use of takhi at one of the release areas, the 570 km2 Hustai National Park in Mongolia. Harem home ranges varied between 129 and 2399 ha, with 80% core areas of between 61 and 1196 ha. There was no relationship between range size and harem size, or length of time since release. Initially, harems stayed near their release enclosures, but over time they established home ranges further away. There was little overlap between home ranges of different harems, but neither was there evidence of exclusive range use. The more nutritious vegetation at lower elevations was preferentially selected. Thus the present situation looks good, but, as the population continues to grow, we anticipate that there will be potential problems related to intraspecific competition for water and vegetation resources, and the potential for hybridisation with domestic horses belonging to the local people. We consider the time it may take for takhi to reach carrying capacity within Hustai National Park and emphasise that continual monitoring of the population is essential because interventional management is likely to be required in the future.  相似文献   
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The Ljubljana-Razdrto highway and the parallel Ljubljana-Trieste railway cut through critical brown bear (Ursus arctos) habitat in south-central Slovenia. These high speed, high volume traffic axes are located close to the main dispersal corridor for bears from the Dinaric Mountain range into the Alps. We analyzed radiotracking data of 15 individual bears that lived within 10 km of the highway, compared transportation related and overall known bear mortality, and analyzed the spatial distribution of bear-vehicle accidents. The highway posed a home range boundary to resident bears, but was not an absolute barrier. Transportation-related mortality was high in the vicinity of the highway and railway, and averaged 31% of the total known local mortality from 1992 to 1999. At present the detrimental impact of transportation routes on the bear population in Slovenia is modest due to the high density of bears and the low density of highways—but new highways are planned or already under construction. Managers have to be aware that, due to bears large home ranges and long dispersal distances, a single highway affects bears from a huge area—emphasizing the importance of international cooperation and a landscape approach in highway planning.  相似文献   
10.
Habitat fragmentation is generally considered to have detrimental effects on insect movement and associated pollen flow between plant populations. Against this background the role of forests as potential barriers for foraging bumblebees of the species Bombus terrestris agg. and Bombus pascuorum was studied in different experiments. Bombus terrestris agg. workers were found foraging at distances of up to 2.2 km from their nests. B. terrestris agg. as well as B. pascuorum individuals crossed 600 m of forestland between floral mass resources (Phacelia tanacetifolia, Helianthus annuus), although in general a high degree of site fidelity was observed. B. pascuorum workers accepted artificial floral resources within the forest, whereas the minor use of resources below forest canopy observed for B. terrestris agg. possibly indicates a preference for direct forage flights, probably leading above the forest canopy. Our results warn against experiments with genetically modified crop species with potential bumblebee pollination (e.g. Brassica napus), in which an isolating effect of forests is assumed.  相似文献   
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