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Sustainability strategies create many synergistic effects for SMEs working collaboratively, as well as systemic benefits for the commons. After setting forth the business case for sustainable SMEs, and considering SME sustainability advantages in contrast to MNEs, this paper discusses several different incentives for SMEs to optimize sustainability: (1) becoming valuable sustainable investment targets for larger firms; (2) creating highly competitive networks of sustainable SMEs in market spaces where large enterprises are less successful; (3) becoming highly efficient suppliers in global supply chains through sustainable practices.While several successful models of the sustainable SME are evolving, it may be that networks of SMEs will become essential for addressing the systemic problems that underlie industrial ecology, enterprise resilience, and global supply chain sustainability. SMEs represent the majority of all enterprises, and rapidly evolving communication technologies allow for various routes of network formation.  相似文献   
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The northeastern offshore population of the pantropical spotted dolphin (Stenella attenuata) in the eastern tropical Pacific remains listed as depleted under the Marine Mammal Protection Act, and recent estimates of abundance show that recovery has been slow. One hypothesis for the slow recovery is that continued chase and encirclement by the tuna fishery negatively affects reproduction. Insufficient life-history sampling in this region over the last two decades makes traditional estimates of reproductive rates impossible. Here, we examine the current reproductive patterns of these dolphins by measuring blubber progesterone (BP) concentrations in biopsy samples to assess pregnancy state. BP was quantified in 212 biopsies from female offshore spotted dolphins sampled between 1998 and 2003 in the northeastern tropical Pacific, and we found that 11.5 % of the biopsied females (mature and immature) were pregnant. The relationship between pregnancy and fishery exposure was analyzed, and we found that pregnant females were exposed to significantly less fishery activity than non-pregnant ones (p = 0.022), suggesting that the fishery may have an inhibitive effect on pregnancy. Spatial analysis indicated that pregnancy was more aggregated than random (p < 0.05) at a scale up to 180-nmi, with the highest proportion pregnant in the mouth of the Gulf of California, an area with relatively low reported fishery activity.  相似文献   
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Local Biodiversity Action Plans are the preferred policy mechanism for setting and delivering local biodiversity targets in the UK. This paper reviews the kind of knowledge conservation scientists envisage being used to identify and set local targets, and explores the means of incorporating local knowledge into this process. We use a case study of a Wildlife Enhancement Scheme (WES) on the Pevensey Levels, East Sussex, to reveal the understandings that local farmers and residents have of the nature conservation goals and practices associated with the scheme. Drawing on the findings of in-depth discussion groups, we show how farmers challenge both the monopoly of knowledge conservationists profess about nature, and the enlistment of farmers on the scheme as «technicians», motivated solely by financial rewards, rather than as knowledgeable experts who also have emotional attachments and ethical values for nature. Local people use their knowledge of both local farmers, and the industry in general, to challenge the assumption that farmers can be trusted with delivering nature conservation goals. In the absence of a commitment by central government to agree widely-held environmental standards, and a more democratic process of making judgements about what local nature is worth conserving, local residents challenge existing processes designed to conserve nature that are driven by the knowledge and practices of official experts alone. The findings of the study suggest that a widening of the knowledge base on which the goals and practices of nature conservation are founded, and a more deliberative process of making decisions about what nature is important locally, will secure and strengthen public support for local biodiversity action plans.1998 Academic Press  相似文献   
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Despite increasing attention to management of headwater streams as sources of water, sediment, and wood to downstream rivers, the extent of headwater channels and perennial flow remain poorly known and inaccurately depicted on topographic maps and in digital hydrographic data. This study reports field mapping of channel head and perennial flow initiation locations in forested landscapes underlain by sandstone and basalt lithologies in Washington State, USA. Contributing source areas were delineated for each feature using a digital elevation model (DEM) as well as a Global Positioning System device in the field. Systematic source area–slope relationships described in other landscapes were not evident for channel heads in either lithology. In addition, substantial variability in DEM-derived source area sizes relative to field-delineated source areas indicates that in this area, identification of an area–slope relationship, should one even exist, would be difficult. However, channel heads and stream heads, here defined as the start of perennial flow, appear to be co-located within both of the lithologies, which together with lateral expansion and contraction of surface water around channel heads on a seasonal cycle in the basalt lithology, suggest a controlling influence of bedrock springs for that location. While management strategies for determining locations of channel heads and perennial flow initiation in comparable areas could assign standard source area sizes based on limited field data collection within that landscape, field-mapped source areas that support perennial flow are much smaller than recognized by current Washington State regulations.  相似文献   
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