人工浮岛技术在北方地区水质改善中的研究进展

人工浮岛技术是近年发展迅速的一种生态污水处理技术,主要应用于富营养化水质的净化。综述了浮岛发展的历史,介绍了建设的种类及方法。宏观地阐述了人工浮岛改善水质的原理,并结合实例,分析了在应用上对处理效果有影响的种种因素。最后对人工浮岛的发展进行了展望。     

甘肃省皋兰县自然资源特点与经济发展研究

本文从皋兰县自然资源和社会经济特征的角度,分析论述了该地区的经济发展的方向和战略目标,指出了实现经济发展目标的具体措施和途径。     

水貂DCT基因5′ UTR克隆分析与启动子活性探究

旨在克隆获得水貂DCT基因5′UTR序列并分析其结构特征,预测转录调控元件并检测启动子活性,为探究DCT基因在调控水貂毛皮颜色形成中的作用提供理论依据。本研究利用PCR扩增黑貂、白貂和咖啡貂DCT基因5′UTR,构建咖啡貂DCT基因5′UTR的pGL3-1～pGL3-7和黑貂pGL3-4～pGL3-6缺失片段的荧光素酶报告基因重组质粒,检测各片段的启动子活性;利用亚硫酸氢盐法检测3种毛色水貂DCT基因启动子区CpG岛甲基化水平。结果,克隆获得水貂DCT基因长8 203 bp的5′UTR序列,发现g.7133-7336为长204 bp的转座元件,与其高相似度的100条序列中,一条为蜕皮动物总门线虫纲的索巴利吸虫,其他均来自犬形亚目。P3和P4片段具有显著的启动子活性(P<0.05);咖啡貂的CpG岛甲基化水平显著高于黑貂和白貂(P<0.05);咖啡貂CC单倍型启动子活性显著低于黑貂的TT单倍型片段(P<0.05)。结果表明,水貂DCT基因5′UTR长204 bp的犬形亚目特异短散在元件Can-SINEs由蜕皮动物门的索巴利吸虫侵入动物基因组形成;基因上游32 bp元件和近端域共同作用发挥启动子活性,而GC-box和CpG岛结构沉默水貂DCT基因启动;g.-684和g.-621位点的T> C突变形成的CC单倍型导致咖啡貂DCT基因的高甲基化与低启动子活性,从而抑制真黑素合成,产生咖啡色被毛特征。     

Insular mammalian fauna dynamics and paleogeography: A lesson from the Western Mediterranean islands

Since the time of Darwin (1859) and Wallace (1869), islands have been regarded by scientists as a prime target for scrutinizing the forces that may influence evolution and diversification and important elements in biogeographic studies. This research aims to scrutinize whether and to what extent the composition and structure of past mammal insular faunas and their changes through time may provide sound clues for inferring the paleogeographical evolution of a region. As a case study, I critically analyzed the dynamics shown by the Plio–Pleistocene mammalian fauna of 3 Western Mediterranean insular districts, the Balearic Islands, Sardinia and Sicily, each characterized by its own peculiar paleobiogeographical evolutionary history. The revision of faunas and the critical analysis of the dispersal ability of the ancestors of island settlers have allowed hypothesizing on the time and mode of island colonization. The results obtained confirm that the early isolation of the Balearic Islands from the mainland led to the establishment of an endemic fauna since the pre‐Messinian Miocene (?Astaracian European Land Mammal Age, MN7/8), and that Sardinia has definitely been isolated since the Pliocene, although dispersal events led to some faunal turnovers during the Pleistocene. In addition, the results suggest for Sicily a complex, still imperfectly disentangled history of alternate phases of complete separation and sporadic, more or less difficult connections with southern Italy.     

舟山海域无居民海岛保护现状及分析

随着《海岛保护法》的颁布实施,将掀起新一轮的海岛保护热情;本文对舟山无居民海岛保护现状进行调查,针对不同保护形式的效果进行分析;讨论提出相关建议,为下步海岛保护工作提供借鉴。     

Wishful sinking: Disappearing islands,climate refugees and cosmopolitan experimentation

Disappearing islands and climate refugees have become signifiers of the scale and urgency of uneven impacts of climate change. This paper offers a critical account of how sea level rise debates reverberate around Western mythologies of island laboratories. I argue that representations of low‐lying Oceania islands as experimental spaces burden these sites with providing proof of a global climate change crisis. The emergence of Tuvalu as a climate change ‘canary’ has inscribed its islands as a location where developed world anxieties about global climate change are articulated. As Tuvalu islands and Tuvaluan bodies become sites to concretize climate science's statistical abstractions, they can enforce an eco‐colonial gaze on Tuvalu and its inhabitants. Expressions of ‘wishful sinking’ create a problematic moral geography in some prominent environmentalist narratives: only after they disappear are the islands useful as an absolute truth of the urgency of climate change, and thus a prompt to save the rest of the planet.     

人工诱发鸡大肠杆菌病的接种规律

采用鸡大肠杆菌 O2标准强毒株 ,对 4 80羽宝万斯 -高兰蛋雏鸡颈部皮下注射进行人工发病 ,研究了细菌培养时间、接种量与致病力之间的关系和规律。结果表明 ,在同一毒株条件下 ,细菌致病力强弱 ,主要取决于接种感染菌数 ,只要接种菌数适宜 ,4～ 2 4 h细菌培养液均可成功发病 ,不必受普遍采用 1 8h细菌培养液接种的时间约束。这一试验结果可为灵活、合理安排抗菌新兽药试验中人工病例复制提供参考     

Spatial and seasonal differences in the top predators of Easter Island: Essential data for implementing the new Rapa Nui multiple‐uses marine protected area

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Marine protected areas invaded by floating anthropogenic litter: An example from the South Pacific

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鄂尔多斯高原北缘唐古特白刺灌丛沙包的空间分布格局分析

采用Ripley’s K函数（L函数）和J函数对研究区内典型样方的白刺灌丛沙包进行点格局和标记点格局分析。结果表明:在独贵塔拉镇,白刺灌丛沙包在小尺度上呈现均匀分布格局（0～5.0 m）,在中大尺度上则呈现随机分布格局（5.0～50.0 m）;在呼和木独镇小尺度上呈现均匀分布格局（0～8.0 m）,在中大尺度上则呈现随机分布格局（8.0～50.0m）;在巴拉贡镇小尺度上呈现均匀分布格局（0～3.5 m）,中小尺度上呈现随机分布（3.5～10.5 m）,中尺度上呈现聚集分布格局（10.5～19.5 m）,在中大尺度上又呈现出随机分布格局（19.5～50.0 m）,而标记点格局分析较点格局分析在尺度上表现得更详细、更准确,例如在独贵塔拉镇,白刺灌丛沙包呈现均匀分布格局的尺度是2.9～11.6 m,呈现随机分布格局的尺度是0～2.9 m、11.6～13.5 m和14.2～50.0 m。造成唐古特白刺灌丛沙包不同分布格局的原因很多,在该区主要是由于水分条件引起的环境异质性所致。最后分析了唐古特白刺灌丛沙包空间格局的环境解释及生态学意义,并建议要在充分考虑其空间格局与尺度间的关系以及不同演替阶段的基础上进行合理开发与利用、保护和恢复。