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201.
Intellectual property is increasingly a key item on the US–Japanese–European trade agenda, and the globalisation of the US patent standard, which includes patents on plants and processes, has become a key objective of ‘information-rich’ corporations and countries. While social movements act against the legal structures and spaces of knowledge associated with privatised knowledge, they also work to construct alternatives both through the development of practical alternatives such as seed-saving networks and the articulation of new discourses such as Farmers’ Rights. In doing so, farmers’ organisations are actively creating and maintaining spaces of alternative knowledges and formulations of property. The articulation of Farmers’ Rights by social movements as a response to intellectual property is a way both of resisting regimes of intellectual property and of creating a normative framework within which claims to intellectual property are made obsolete. Drawing from empirical work based in the Philippines, I propose a concept, woven space, which refers to the diverse and overlapping alternatives and resistances that emerge from the situated and embodied struggles taking place around the world to form a differently imagined and realised global. This is a decentralised, networked space, rich with experience, shared belief, and possibilities for shared action.  相似文献   
202.
Fullerene (nC60) and nanosilver (nAg) are nanomaterials with bactericide properties. The increments in their use raise questions about their potential environmental impacts, including estuarine ones. The polychaete Laeonereis acuta (Nereididae) secretes mucus that is colonized by bacteria communities. We analyzed the antioxidant and oxidative damage responses of anterior, middle and posterior region of L. acuta and bacteria communities after nC60 or nAg exposure during 24 h. Molecular analysis showed a prevalence of Vibrio genera in the communities. Bacteria biomass was lowered in worms exposed to 1.0 mg/L of nAg. nC60 reduced total antioxidant capacity of bacteria from worms exposed to 0.1 mg/L. Worms anterior region presented lower antioxidant capacity after exposure to 1.0 mg nC60/L, and the same was observed in the posterior region of worms exposed to 1.0 mg nAg/L. Lipid peroxidation was reduced in the anterior region of worms exposed to nC60 and the opposite was observed in the posterior region.  相似文献   
203.
王咏  陆林 《地理学报》2014,69(10):1557-1574
门户社区毗邻风景区且处于其出入口位置,在旅游发展中面临特殊的机遇和难题.依据社会交换理论,选择“社区参与度”、“居住区条件”、“对旅游机构信任度”、“旅游利益感知”、“旅游成本感知”、“社区满意度”和“旅游支持度”7 个结构变量构建社区旅游支持度测度模型,以黄山风景区的4 个门户社区为研究案例,对该模型进行检验,通过结构方程模型分析和因子分析,探讨模型内各变量对社区旅游支持度发挥作用的路径及造成同一风景区不同门户社区支持度差异的影响因素.研究结果表明:① 总体而言,旅游利益感知和社区满意度对旅游支持度有正向影响;居住区条件、对旅游机构信任度和社区满意度对旅游利益感知有正向影响;社区参与度、居住区条件和对旅游机构信任度对社区满意度有正向影响.社区参与度对旅游利益感知正向影响不显著,旅游成本感知这一变量与其他变量之间关系不大.②各地居民感知和旅游支持度存在差异,南门汤口各维度总体得分最高,北门甘棠-耿城次之,东门谭家桥第三,西门焦村得分最低.③ 门户社区与黄山风景区的空间关系、区位条件与交通格局、旅游经济发展水平等因素造成了各门户社区旅游支持度的差异.  相似文献   
204.
本文旨在用17年的观测数据检验三个有关草地系统演替的假设:(1)物种多样性在演替早期不断增加;(2)伴随着演替的推进,样方植物群落间的相似度逐渐增加(样方间的差异度随着演替不断降低);(3)在演替早期,植物群落的物种组成有趋同之势。包括植物群落的总体发展、Shannon多度与均度、Bray-Curtis差异度和群落周转率在内的量化统计结果显示:经过早期5年的演替,各样方的物种多样性表现出快速的趋同,多度均值逐渐由8增加至25个物种;同时,所有样方的物种总数由23增加至55个物种,标准方差由4.6降至0.3。此外,样方间的差异度逐渐降低,物种多度与组成呈明显的趋同。停止除草的一个重要效应是,人工设置的由1到16个物种的多样性梯度因物种入侵至多度较低的样地而减弱。  相似文献   
205.
206.
《Marine pollution bulletin》2014,78(1-2):252-257
An experiment observed the behavior of selected tagged plastic items deliberately released in different habitats of a tropical mangrove forest in NE Brazil in late rainy (September) and late dry (March) seasons. Significant differences were not reported among seasons. However, marine debris retention varied among habitats, according to characteristics such as hydrodynamic (i.e., flow rates and volume transported) and relative vegetation (Rhizophora mangle) height and density. The highest grounds retained significantly more items when compared to the borders of the river and the tidal creek. Among the used tagged items, PET bottles were more observed and margarine tubs were less observed, being easily transported to adjacent habitats. Plastic bags were the items most retained near the releasing site. The balance between items retained and items lost was positive, demonstrating that mangrove forests tend to retain plastic marine debris for long periods (months-years).  相似文献   
207.
During the last several decades, the Mediterranean littoral shallow water benthic communities have suffered significant changes in their structure and taxa composition. Despite numerous studies conducted to characterize these changes at various levels, it has always been very difficult to disentangle the effects of natural factors from anthropic ones. The main purpose of this work was to evaluate possible changes, over a 10‐year scale, in diversity and abundance of the most representative species of the benthic communities considered to be primarily and potentially affected by natural stressors in a highly protected area. Sets of macro‐photographs were taken in 2002–2003 of three sites inside a small bay called Ca’ dell'Oro, which is the “no entry—no take” zone of the Marine Protected Area of Portofino, in order to analyse the structure of the benthic communities at different depths over a short time scale. The same sampling was repeated 10 years later in 2013. In the 10‐year span, a significant change in the macroalgal coverage and composition was observed, while the overall richness and coverage of species remained almost unchanged. This process resulted in a significant reduction of the habitat complexity of the three‐dimensional algal components. Likewise, a remarkable change in terms of presence and abundance occurred among all zoobenthic components. The benthic communities seem to have suffered from detrimental effects probably caused by climatic events that have been occurring in recent years in the Ligurian Sea.  相似文献   
208.
Feeding of captive Galaxias vulgaris was found to be dependent on open‐water activity. It did not occur when fish remained beneath boulders. Pat'erns of spontaneous locornotory activity of individual fish were recorded to determine potential feeding times. The apparatus used to measure spontaneous locomotory activity is described. Fish were found to be active mainly at night for most of the year, but became predominantly diurnal during the spawning period.  相似文献   
209.
Parameters of community structure (species composition and relative abundance, number of taxa, diversity, evenness, and cell density) were measured for a mudflat diatom community in the Avon‐Heathcote estuary, New Zealand. Fifty three diatom species were identified: 25 taxa (species and varieties) are new New Zealand records. The Shannon‐Wiener information index (H') was 3.46, indicating high diversity. Evenness (J') ranged from 0.57–0.67. The association between the biomass of the pulmonate gastropod, Amphibola crenata, and benthic diatom community structure was studied using large open enclosures (4.0 m2) to manipulate snail biomass. Community structure was compared at 0, 5 (natural biomass), and 10 g A. crenata dry weight per m. A similarity index (SIMI=0.88–0.95), as well as H’ and J’ indicated close similarity between the diatom assemblages within all enclosures, but number of taxa increased from 33 to 49 with increasing snail biomass. Cell densities were significantly lower at high snail biomass (6088 valves per mm2) compared to enclosures with no snails (10 110 valves per mm ). A. crenata had a higher ratio of diatom fragments to whole diatom valves in its faeces (2.42) than in its crop (0.55), indicating that it is capable of fragmenting diatoms.  相似文献   
210.
陈传明 《湿地科学》2012,10(3):359-364
自然保护区的建立对改善区域生态环境、保护生物多样性和恢复生态系统功能具有重要作用.如何处理自然保护区生态保护与毗邻社区社会经济发展之间的关系,是当前自然保护区研究者、决策者和社区居民共同关注的问题.利用文献调研法、问卷调查法、访谈法和意愿调查法等,分析福建漳江口红树林国家级自然保护区的建立对毗邻社区居民的影响.研究结果表明,大部分社区居民对福建漳江口红树林国家级自然保护区的建立持赞同态度,这种态度受被调查者的教育程度、年龄和性别的影响;保护区的建立使大多数社区居民收入减少,而社区居民没有得到相应的补偿;社区居民面临着缺少资金、补偿制度缺失和缺乏生产技术等问题;提出了福建漳江口红树林国家级自然保护区毗邻社区社会经济可持续发展的建议.  相似文献   
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