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为了了解大黄鱼(Larimichthys crocea)野生群体和养殖群体脊椎骨骨骼显微结构的差异,本研究运用了Micro CT技术对大黄鱼全鱼骨骼系统进行了扫描与三维重建,选取野生群体和养殖群体背部和尾部脊椎骨进行了显微结构参数差异分析。结果显示,大黄鱼脊椎骨与头骨、尾骨相连,脊椎骨26个,肋骨附着在第1~11腹椎,无肌间刺,胸鳍位于头骨后,背鳍、腹鳍、臀鳍和尾鳍与脊椎骨并不相连。大黄鱼野生群体背部和尾部脊椎骨的组织矿物质密度和骨矿物质密度均显著高于养殖群体(P0.01),骨体积分数较养殖群体大(P0.05),骨小梁间隔较养殖群体小(P0.05),骨小梁数量、骨小梁厚度和结构模型指数上没有差别。推测是由于野生群体和养殖群体食物组成、生活环境以及活动情况等差异造成的。  相似文献   
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Acid sulphate soils (ASS), which occur on floodplains worldwide, pose a significant threat to estuarine ecosystems. In laboratory and field experiments, naïve calcifying organisms that are exposed for even short periods (1–2 mo) to runoff from ASS suffer 80% mortality and slowed growth. Based on these observations we expected that sampling of wild oyster, gastropod and crab populations at sites close to and away from drains discharging ASS runoff would reveal more depauperate populations, of sparser and smaller-sized individuals at the more acidified sites. Sampling within three estuaries of New South Wales, Australia, confirmed that the oyster Saccostrea glomerata and gastropods (primarily Bembicium auratum) were less abundant at ASS-affected than reference sites. Nevertheless, crab abundances did not differ between the acidified and reference sites and impacts to bivalves and gastropods were far smaller than predicted. Although at ASS-affected sites gastropod populations were dominated by smaller individuals than at reference sites, oyster populations were skewed towards larger individuals. Even at ASS-affected sites, oyster and gastropod abundances were within the range encountered in estuaries that are not influenced by ASS runoff. Behaviour, long-term physiological acclimation or genetic selection may be responsible for differences in the responses of wild and naïve macroinvertebrates to acidification. Alternatively, wild populations may exhibit some recovery between the rainfall events that transport ASS runoff into estuaries, despite the persistently lower pH near outflow drains. Irrespective, this study suggests that at the population level, calcifying organisms display a certain degree of natural resistance to recurrent disturbance from ASS runoff.  相似文献   
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South Africa's organically emerged cultural business of traditional healing is almost exclusively reliant on wild-harvested resources extracted from wilderness areas or open-access commons. The wild medicine business has been described for much of South Africa, although is little understood in Cape Town, the urban centerpiece of the Cape Floristic Region (CFR). A census of different traditional healer typologies in five typical working-class residential areas (representing ~71,500 residents) was conducted to assess the nature and extent of traditional medicine harvesting and trade. Extrapolating these findings for the city reveals a local industry of more than 15,000 practitioners collectively conducting trade worth US $15.6 million per year. More than 40% of the volume of traditional medicines traded in the city is harvested from the CFR. Future conservation approaches must consider that the business of traditional healing and dispensing wild-harvested medicines is both economically important and culturally entrenched.  相似文献   
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西北地区野生药材资源和野生植物资源的滥采乱挖不仅引起了资源的迅速衰竭,而且还破坏了当地的草地资源,区域的生态环境也随之渐趋恶化。从产权制度、许可制度、保护制度等资源法律制度入手分析了滥采乱挖屡禁不止的主要原因,并进而提出了加强资源法制建设的多种途径和对策:(1)完善资源产权制度,实现资源产权的具体化、实体化;(2)依法行政,实现资源开发利用和经营的法制化管理;(3)重新审视资源的价值,合理确定资源的保护级别;(4)加强资源法制宣传,提高群众的法律意识。  相似文献   
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大别山地处鄂、豫、皖三省交界处,自然环境复杂多样,野生植物资源和花卉资源较为丰富,约有野生花卉植物380种。本文探讨了大别山野生花卉资源的特点,列举了一些开发利用价值大的花卉的特征、生活习性和利用方式。  相似文献   
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