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991.
论产业集群的知识协作机制 总被引:11,自引:0,他引:11
产业集群的知识协作机制包括:信任机制和知识共享机制。其信任机制表现为:集群信任的形成是企业个体(或私人)的内在利益诉求的必然结果,也是集群环境下市场选择与市场竞争监督的“社会实施”的产物;其知识共享机制表现为:集群的空间集聚与信任特征创造了“面对面交流”的有利条件,集群的社会文化特征促进集群整体默会性知识的扩散与共享,集群的网络特征加速知识外溢与创意流动,为群内企业工作人员的知识开发与创造构筑协作平台。 相似文献
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Successfully engaging target audiences represents a key challenge for environmental conservation projects. In this study, we examined 354 conservation projects implemented across the United States with the intention of systematically exploring the relationships between different forms of outreach (in particular, message content and delivery) and self-reported project outcomes. Using end-of-program retrospective surveys, we found that experiential engagement and directly demonstrating and/or communicating the ease of potential conservation actions were most consistently related to achieving desired project outcomes. Although it was thought to be largely effective by project managers, we found that focusing on equipping audiences with new knowledge was negatively related to conservation outcomes. Measured outreach variables explained between 15% and 17% of the variance in project outcomes, suggesting a wide variety of unmeasured factors at play. We discuss insights relevant to engaging target audiences in future U.S. conservation projects. 相似文献
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996.
《Marine Policy》2016
Ecosystem management (EM) requires new tools to facilitate stakeholder access to information and analysis, however these tools are often not perceived by stakeholders to be usable, useful, and salient to their concerns. This paper provides a case study which applies new participatory design methods, known as design thinking, to create an EM tool called the Great Lakes Aquatic Habitat Explorer. Both participating and non-participating stakeholders rated the usability of the resulting tool positively, and stakeholders who attended design workshops rated the perceived usefulness and salience of the resulting tool more highly than those who had not. Design workshop survey data found that the methods produced an environment of collaborative learning among participants, including diverse participants, authentic dialog, and creativity. Design thinking methods hold promise for the development of new tools which better respond to the needs of EM stakeholders. 相似文献
997.
甘肃沙葱的地理分布与群落结构特征 总被引:3,自引:0,他引:3
甘肃沙葱主要分布于河西走廊北部荒漠区及白银、兰州市的西北部部分县(区)的黄土低山丘陵区,分布区总面积约125 715.9km2。有气候和土壤因素形成的两种生态类型,且沙葱荒漠的物种组成成分相对简单,共有76种,分属14科45属;群落类型可划分为5类14个群丛组合,表现出以超旱生小灌木层片、强旱生小半灌木层片及沙旱生草层片为主的旱生结构特征。此外,甘肃沙葱种群及群落表现出均匀度低、优势度高、分布范围广、群落结构单一、适应性极强、具有地域性等特征。 相似文献
998.
The invertebrate benthic community of two Aveiro salt pond systems was studied in order to evaluate its diversity, density and the influence of organic matter and salt production. Samples were collected monthly at Esmolas and Tanoeiras. Five groups of benthic organisms were found: Nemathelminthes, Annelida (Nereis diversicolor), Crustacea (Sphaeroma serratum andTanais cavolini), Insecta (Chironomidae), Bivalvia Mollusca (Cerastoderma edule, Spisula solida andMya arenaria) and Gasteropoda Mollusca (Hydrobia ulvae, Cingulla cingullus, Cingulla semistriata, Odostomia rissoides, Odostomia unidentata, Scrobicularia alba, Valvata cristata andPaludestrina acuta). The highest density of the benthic community was observed during the non-productive season in all but the crystallizing pond systems. In both salt ponds, salinity acted as limiting factor. The dominant group was Gasteropoda, although high densities of Bivalvia were recorded in some ponds. In the feeder pond and the channels, species diversity was highest in the Tanoeiras salt pond, probably because its physical and chemical characteristics allowed the development of stable communities. 相似文献
999.
青藏铁路温性草原区路域植被自然恢复过程中群落组成和物种多样性变化 总被引:8,自引:0,他引:8
以芨芨草和短花针茅为优势种的温性草原是青藏铁路进入海拔3000m以上地区所穿越的第一个地带性植被类型。在青藏铁路经过的温性草原区对未受筑路直接影响的区域、取土区、铁路路基、周围其它类型的公路路域植被进行取样,并对群落组成和有关群落特征进行了比较,以讨论青藏铁路的修建与运营对温性草原及其恢复过程的影响。结果显示,青藏铁路修筑过程对铁路两侧一定区域的温性草原有较大影响,但随着受影响区域植被的自然恢复,群落盖度、生态优势度和物种多样性等反应群落特征的指标都有一定程度的改善,一些在原生植被中很少出现或伴生种在恢复后的群落中有可能成为群落的优势种或建群种,如露蕊乌头和鹅绒委陵菜等;人为辅助措施将有利于受损植被的恢复;修筑铁路过程中受到影响的温性草原其恢复过程中尚未出现外来入侵植物。 相似文献
1000.
Using multi-mesh gillnets and trawls, the fish communities in Dianshan Lake at 6 stations from Oct. 2009 to Jul. 2010 were investigated seasonally to reveal the biodiversity and its spatial and temporal distribution patterns. The long-term changes in their structural characteristics were then analyzed to identify the main infl uencing factors and several measures for lake restoration were put forward. Thirty six species, belonging to 9 family and 30 genera, were collected, amongst which, the order Cypriniformes accounted for 61.1% of the total species number. In terms of importance value, Cypriniformes was the predominant group, Coilia nasus the dominant species, while Cyprinus carpio and Rhinogobius giurinus were the subdominant taxa. The community types did not differ among stations, but between seasons. There were no significant differences between seasons and among stations in species diversity, but richness differed both spatially and seasonally. Along with the process of eutrophication and the drastic reduction of the area colonized by macrophytes from 1959 to 2009–2010, the fish diversity declined markedly, and species numbers of herbivores and piscivores declined proportionately more than those of invertivores, omnivores, and planktivores. The decline of potamophilus and river-lake migratory fish was more marked than those of sedentary, river-sea migratory, and estuarine fishes. Eutrophication concomitant with sharp reduction of macrophyte area and overfishing may be the main reasons for the decline in fish diversity in Dianshan Lake. 相似文献