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981.
982.
This paper presents reflections on a research project in women's health, providing both substantive findings surrounding tanning and social status and methodological recommendations for future research. The project under review utilized a picture-elicited storytelling method to: a) understand how women link tanned, bronzed skin to health, status, and attractiveness; and b) test the effectiveness of picture-elicited storytelling as a research method. The project found that, when tanning, women use their bodies to inscribe the social norm of the bronzed aesthetic. While women indicate considerable knowledge of the health dangers of tanning, they continue to link tanned skin to beauty, status, and attractiveness. Further, the research project found that the use of picture-elicited storytelling as a method is potentially powerful but requires considerable attention to concerns of power and representation on the part of the research team.  相似文献   
983.
根据近十年平潭海域生态环境调查资料与旅游经济产业发展数据,结合夜光藻赤潮观测资料,通过构建海洋生态-旅游经济复合系统协同发展评价体系,运用耦合、协同、脱钩评价方法对平潭海洋生态-旅游经济复合系统协同发展水平进行测度评价,从时间层面上分析海洋生态环境安全与旅游经济发展的协同强度和发展态势。研究结果表明:(1) 2009-2019年,平潭旅游经济呈线性上升趋势,而海洋生态系统演化呈较为平缓的波动上升趋势,海洋生态-旅游经济复合系统逐渐向高水平耦合阶段演化;(2)平潭海洋生态-旅游经济复合系统发展在研究期间处于非协同或低协同状态,但发展态势和协同程度有所上升;(3)废水排放入海量、废水中COD排放量、废水中氨氮排放量与平潭旅游经济发展呈较为理想的脱钩状态,废水中的有机污染物排放浓度逐年降低;(4)夜光藻赤潮持续天数与平潭旅游经济增长的脱钩指数波动较大,营养盐水平与夜光藻赤潮发生频次的相关性并不明显。基于以上研究结果,本文提出引入具有协同效应的巨涨落机制等对策建议,以期实现平潭海洋生态-旅游经济复合系统的提质升级。  相似文献   
984.
董旭辉  羊向东 《湖泊科学》2012,24(6):974-984
全球范围内的湖泊生态环境均出现了不同程度的退化,对其进行生态修复的最终目的,就是要将受损的生态系统尽量恢复到人类干扰前或接近人类干扰前的生态状况,即基准环境.湖泊生态系统是长期演化的产物,其形成及演化机制必须从历史的视角加以考察,因此基于湖泊沉积物的古生态学技术在制定基准环境方面有着独特的优势.本文从基准环境的定义、建立的常用方法、基本特征和典型应用几个方面介绍了古生态学手段在湖泊生态修复中的应用,提出中国今后利用古生态学手段在水环境治理工作的应用前景.  相似文献   
985.
三江平原沼泽地主养鲤鱼塘能量转换效率研究   总被引:1,自引:0,他引:1  
杨富亿 《湖泊科学》1995,7(3):263-270
对1988~1992年三江平原沼泽地泥炭池主养鲤鱼生态系统的能量转换效率进行了研究分析。结果表明,一个生长期浮游植物毛初级生产力对太阳辐射能的转换效率为0.204~0.308%;鲢鳙净产量对浮游植物净产量的转换效率为1.195~4.815%;太阳能转换为鱼类总净产量的生态学效率为0.067~0.123%。总辅助能、总生物能和饲料辅助能转换为鱼类总净产量的效率分别为8.91~14.05%、10.96~17.20%和11.06~17.57%.在2500kg/hm~2、3500kg/hm~2及5000kg/hm~2三个净产量级型池塘中,以5000kg/hm~2产量级的能量转换效率为最佳型。  相似文献   
986.
庄德辉 《湖泊科学》1993,5(1):85-91
本文综述酸雨对水生态系统中各营养级生物的影响。介绍酸雨引起水体酸化和水体的缓冲能力,阐述不同营养级水生生物和所处不同发育阶段对低pH的敏感性差异。还讨论了由于遗传和适应引起生物对低pH的耐受性差异。酸化水体生物群落的重要特征是,生物种类数减少,多样性降低,生物量减少和食物链遭破坏。酸性pH对水生生物的毒作用方式包括气体交换受阻、体盐调节紊乱、酸碱平衡失调,以及与金属的联合作用等.最后还对若干问题作了扼要讨论,并提出建议。  相似文献   
987.
闫晗  惠敏  沙忠利  程娇 《海洋与湖沼》2023,54(5):1463-1475
劳盆拟刺铠虾(Munidopsis lauensis)是一种十足目铠甲虾, 能够适应深海化能合成生态系统的极端环境, 但是其已知基因序列信息却很少。为此, 采用PacBio平台的SMRT测序技术对来自南海台西南冷泉劳盆拟刺铠虾的肝胰腺、鳃、肌肉和肠混合组织进行了三代全长转录组测序。通过聚类、校正、去冗余之后共获得28 811条高质量isoform, 平均长度为2 086 bp, N50长度为2 275 bp。使用Nr、SwissPort、KEGG、KOG数据库对转录本序列进行功能注释, 共有20 616 (71.56%)条isoform得到注释。进一步高级注释共获得21 848个蛋白编码序列, 共预测到537个转录因子、6 430个长链非编码RNA和10 060个SSRs位点。KEGG通路分析发现两条可能与劳盆拟刺铠虾适应深海化能极端生境相关的通路, 分别为过氧化物酶体通路和谷胱甘肽代谢通路。其中, 共有180条isoform被发现参与编码过氧化物酶体通路中的31个关键酶, 213条isoform参与谷胱甘肽代谢通路中19个关键酶的编码。基于全长转录组数据, 利用同源比对、功能结构域预测及系统发育树构建等方法对劳盆拟刺铠虾谷胱甘肽S-转移酶(GST)基因家族进行挖掘与鉴定, 共发现属于theta、delta、mu、kappa四种亚家族的20条GST候选序列。通过对劳盆拟刺铠虾全长转录组测序、功能注释和环境适应相关的重要基因及通路的分析, 不仅丰富了深海组学数据资源, 也为进一步揭示甲壳动物适应深海化能极端环境的分子机制奠定了基础。  相似文献   
988.
The partial pressure of carbon dioxide (pCO2) in estuary-plume systems is related to the internal processes of net organic metabolism and physical mixing, but is also strongly influenced by biogeochemical inputs from the land and ocean. Surface layer pCO2, stimulated fluorescence of chlorophyll (f-chl) and colored organic matter (f-com), and beam attenuation at 660 nm (c-660) were measured during three seasonal surveys of the Kennebec (ME) and Merrimack (MA) estuary-plume systems. These estuaries are both supplied by large New England Rivers and separated by less than 150 km, but significant differences were often observed in the distributions of surface pCO2 and optical variables. High pCO2 concentrations were generally associated with high f-com, while lower pCO2 concentrations were associated with high f-chl and c-660. Using simple regression models, optical measurements were used to estimate chlorophyll and total organic carbon concentrations. Results suggest that labile riverine carbon is responsible for sustaining supersaturated pCO2 conditions and that phytoplankton productivity, likely driven by inputs of riverine dissolved inorganic nitrogen, is responsible for pCO2 undersaturation. Although optical variables are often related to surface pCO2, the results suggest that efforts to retrieve pCO2 in complex waters using optical data may be enhanced using a site-specific, multivariate approach.  相似文献   
989.
Carbon, nitrogen, and phosphorus flow networks, consisting of 59 compartments, were constructed for the Sylt-Rømø Bight, a large shallow sea in the German Wadden Sea. These networks were analysed using ecological network analysis. Each network depicts the standing stock of each component in the ecosystem, and the flows between them. The trophic efficiency by which material is utilised in the Bight increase from 3%, to 6% to 17% for C, N and P, respectively. The number of cycles though which these elements pass increase from 1 197 for carbon, to 414?744 and 538?800 for nitrogen and phosphorus, respectively. The Finn Cycling Index, reflecting the amount of material recycled as a fraction of the total system activity, TST, increases from 17% for carbon, to 43% for nitrogen, to 81% for phosphorus. Other system level attributes such as the Average Path Length, the Average Internal Mutual Information, Relative Ascendancy, Relative and Normalized Redundancy, show an increase from the carbon to the nitrogen to the phosphorus networks. Phosphorus is tightly cycled over longer pathways than the other two elements, and also has the longest residence time in the Bight. Postulated differences between the behaviour of energy (or carbon) and biogeochemical networks in coastal ecosystems are evident from the results obtained from ecological network analysis.  相似文献   
990.
Implementing ecosystem-based management requires methods of assessing the quality of habitats to deliver the high-level objective of achieving healthy ecosystems. ‘Habitat’ has been interpreted in different ways and this has confused the debate over which attributes constitute ‘quality’. Three definitions of quality for habitats are advanced: ‘species’, ‘reference’ and ‘functional’ . Operational measures associated with these are evaluated in terms of their utility to deliver policy objectives. It is concluded that functional definitions/measures of quality are most appropriate to deliver ecosystem-based management although measures of species and reference quality may support assessment of the functional quality of habitats.  相似文献   
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