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291.
Abstract

Media and academic debates about the environment have increasingly made reference to the so-called ‘eco-preneur’ (‘green entrepreneur’ or ‘environmental entrepreneur’). These discussions encourage us to see the potential of such figures to act as drivers of environmental innovation. Their combination of entrepreneurial zeal and green motivations is seen as providing them with the ability to transcend the usual tensions between business and the environment. In academic circles a new literature is beginning to emerge around this perspective, ‘eco-preneurship’. In this paper we investigate the usefulness of eco-preneurship for understanding environmental innovation. In particular we ask where this literature, supported by popular images in the media, fixes our gaze when we think about environmental innovation in society. And, crucially, what might we be missing by concentrating our attention on these eco-preneurs? The paper concludes by suggesting that environmental innovation is better understood as an inherently messy and complex institutional process, which cannot be reduced to the psychology of entrepreneurial personalities.  相似文献   
292.
A Derivation of the Marginal Abatement Cost Curve   总被引:1,自引:0,他引:1  
The relationship between a firm's technology and its marginal abatement cost (MAC) curve is explored. Even under the simplest specifications, the MAC curve will be kinked at some point except under a special assumption which, in reality, could easily be violated. The nondifferentiability implies that the choice of instrument under uncertainty may depend on the targeted level of emissions reduction. Also, stability conditions for dynamic tax mechanisms may be violated in the neighborhood of the kink point. A policy implication is that in some cases output restrictions are as efficient as emissions restrictions, in contrast to previous results.  相似文献   
293.
The paper discusses conditions and format of a cluster model to support the management of a potential creative tourism destination in a setting where regional cross-sectoral collaboration is lacking. Creative tourism development requires a flexible framework and a healthy collaboration environment, more so when associated with resources shared by several stakeholders. This article focuses on the tourism potential of archaeological knowledge discovered during the environmental impact assessment of the Alqueva dam (Alentejo, Portugal). Interviews were conducted with 38 regional actors in the tourism and heritage sectors, as well as the dam developers and the companies responsible for archaeological interventions. Findings indicate that the lack of specific local policy addressing archaeological heritage hampers its potential use for tourism development, which is further aggravated by the absence of stakeholder communication and cooperation. A conceptual cluster model for the management of creative tourism destinations based on heritage resources and other local resources is proposed.  相似文献   
294.
This study examined the capacity for photoprotection and repair of photo-inactivated photosystem II in the same Symbiodinium clade associated with two coexisting coral species during high-light stress in order to test for the modulation of the symbiont’s photobiological response by the coral host. After 4 days exposure to in situ irradiance, symbionts of the bleaching-sensitive Pocillopora damicornis showed rapid synthesis of photoprotective pigments (by 44 %) and strongly enhanced rates of xanthophyll cycling (by 446 %) while being insufficient to prevent photoinhibition (sustained loss in F v/F m at night) and loss of symbionts after 4 days. By contrast, Pavona decussata showed no significant changes in F v/F m, symbiont density or xanthophyll cycling. Given the association with the same Symbiodinium clade in both coral species, our findings suggest that symbionts in the two species examined may experience different in hospite light conditions as a result of different biometric properties of the coral host.  相似文献   
295.
Abstract

This report discusses the responsibilities of government for the legislation of pesticides, and describes the impact of various statutes on the use of pesticides in agriculture. Governmental responsibilities for management of the economy, education, and enactment of laws and regulations are discussed, and the history of U.S. legislation of pesticides and related substances is presented. Finally, the impact of pesticide regulation on international trade is considered.  相似文献   
296.
Degradation of farmland caused by salinisation is a major environmental issue in Australia. To combat salinisation a community-based approach has been adopted. This paper reviews the nature and effectiveness of this approach, describing its rationale, strengths and weaknesses. The community-based approach is shown to have been highly successful in raising awareness and providing education about the problem of dryland salinity in Australia, and has encouraged group participation in managing the problem. The approach has allowed some internalisation of the externalities associated with dryland salinity, with peer group and community pressure helping to address some salinity problems. However, the approach has not greatly lessened the threat of salinisation. Community and regional groups continue to receive the bulk of salinity management funding yet it is funding for development of new innovations, technologies and policies that is also critical to combating salinity. A conclusion is that there may have been an over-investment in the community-based approach and under-investment in the development of skills and research infrastructure required to develop innovative solutions to lessen the cost of salinity. Readers should send their comments on this paper to BhaskarNath@aol.com within 3 months of publication of this issue.  相似文献   
297.
The effect of dairy farming on water quality in New Zealand streams has been identified as an important environmental issue. Stream fencing, to keep cattle out of streams, is seen as a way to improve water quality. Fencing ensures that cattle cannot defecate in the stream, prevents bank erosion, and protects the aquatic habitat. Stream fencing targets have been set by the dairy industry. In this paper the results of a study to identify the factors influencing dairy farmers' decisions to adopt stream fencing are outlined. Qualitative methods were used to gather data from 30 dairy farmers in four New Zealand catchments. Results suggest that farm contextual factors influenced farmers' decision making when considering stream fencing. Farmers were classified into four segments based on their reasons for investing in stream fencing. These reasons were fencing boundaries, fencing for stock control, fencing to protect animal health, and fencing because of pressure to conform to local government guidelines or industry codes of practice. This suggests that adoption may be slow in the absence of on-farm benefits, that promotion of stream fencing needs to be strongly linked to on-farm benefits, and that regulation could play a role in ensuring greater adoption of stream fencing.  相似文献   
298.
299.
The succession of a mixed species stand of the Acadian Forest was simulated by adopting an approach taken by Botkin et al. (1972) (JABOWA) and later modified by Shugart and West (1977) (FORET). The model simulates the dynamic aspects of successional behaviour of the stand by projecting the current stage of vegetation composition (size of each individual of each species present on a 1/12 ha plot) with an element of randomness. The growth of each tree is modeled as a function of its size (represented by its diameter at breast height (dbh), height and leaf area index), the climate, the tree's tolerance to shade and the competition for available resources and space. Stand aboveground biomass (metric ton/ha), leaf area index, number of trees/ha and species composition of the stand were simulated under seven different conditions: (a) normal treatment, (b) increasing biomass maximum 30%, (c) decreasing biomass maximum 30%, (d) increasing degree-days 30%, (e) decreasing degree-days 30%, (f) increasing light extinction coefficient 30% and (g) decreasing light extinction coefficient 30%. Under the first set of conditions (normal treatment), the aboveground biomass reached a maximum value during the first hundred years, decreased during the second, and remained stable for the rest of the 500-year simulation period. The leaf area showed a similar pattern. The total number of trees/ha decreased sharply during the first fifty years and reached a stable value by the end of the first hundred years. Successional patterns and species competitive abilities were interpreted from the accumulated biomass of each species over the simulation period under the different treatments.Species composition of the stand under the normal treatment showed dominance of deciduous species at early stages of succession, with conifer species being increased and becoming dominant at the end of the simulation period. When the climate was raised 30% (warmer) over the average, the deciduous species continued their dominance over the course of the simulation period. Other simulated species dynamics also appeared to follow what is known about their successional behaviour in the field.  相似文献   
300.
This article analyzes the official and non-official responses of Filipinos to the depletion of some renewable natural resources (particularly water quality). Contrary to popular assumption, and contrary to official statements of the Philippine government at international conferences, it appears that environmental depletion is a political issue in the Philippines. The reasons for the salience of resource and environmental issues are discussed. The dilemma of the Philippine government is that it is committed to economic progress, but the resources which make that progress possible are in short supply. Timber, soil and clean water are endangered by deforestation, erosion and pollution. However, conservation and environmental protection are expensive in the short run. The Philippines faces a problem common to developing tropical countries.  相似文献   
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