推广转基因抗虫棉对次要害虫农药施用的影响分析

本研究的主要目的是分析在转基因抗虫棉有效控制棉花主要害虫(棉铃虫)、减少农药施用之后,可能导致的对棉花次要害虫的影响。通过多年的棉农生产跟踪调查和计量模型分析,研究结果表明,近年来棉农用来控制次要害虫的农药施用量有所增加,应引起有关部门的重视,但它的农药施用量远远小于采用转基因抗虫棉后整体减少施用的农药量;研究还发现,转基因抗虫棉在控制主要害虫农药施用量的减少,不是导致次要害虫农药施用量增加的主要原因,它仅仅能解释次要害虫农药施用增加量的一小部分。     

Investment in soil conservation in northern Ethiopia: the role of land tenure security and public programs

A double hurdle statistical analysis of 250 farms in the Tigray region of Ethiopia reveals different causal factors for soil conservation adoption versus intensity of use. Farmers' reasons for adopting soil conservation measures vary sharply between stone terraces and soil bunds. Long‐term investments in stone terraces were associated with secure land tenure, labour availability, proximity to the farmstead and learning opportunities via the existence of local food‐for‐work (FFW) projects. By contrast, short‐term investments in soil bunds were strongly linked to insecure land tenure and the absence of local food‐for‐work projects. Public conservation campaigns on private plots reduced adoption of both stone terraces and soil bunds. Whereas capacity factors largely influenced the adoption decision, expected returns carried more influence for the intensity of stone terrace adoption (measured as metres of terrace per hectare). More stone terracing was built where fertile but erodible silty soils in higher rainfall areas offered valuable yield benefits. Intensity of terracing was also greater in remote villages where limited off‐farm employment opportunities reduced construction costs. These results highlight the importance of the right kind of public interventions. Direct public involvement in constructing soil conservation structures on private lands appears to undermine incentives for private conservation investments. When done on public lands, however, public conservation activities may encourage private soil conservation by example. Secure land tenure rights clearly reinforce private incentives to make long‐term investments in soil conservation.     

Can tourism be part of the decarbonized global economy? The costs and risks of alternate carbon reduction policy pathways

Global leaders agree on the need to substantially decarbonize the global economy by 2050. This paper compares potential costs associated with different policy pathways to achieve tourism sector emission reduction ambitions (?50% by 2035) and transform the sector to be part of the mid-century decarbonized economy (?70% by 2050). Investment in emissions abatement within the tourism sector, combined with strategic external carbon offsets, was found to be approximately 5% more cost effective over the period 2015–2050 than exclusive reliance on offsetting. The cost to achieve the ?50% target through abatement and strategic offsetting, while significant, represents less than 0.1% of the estimated global tourism economy in 2020 and 3.6% in 2050. Distributed equally among all tourists (international and domestic), the cost of a low-carbon tourism sector is estimated at US$11 per trip, equivalent to many current travel fees or taxes. Exclusive reliance on offsetting would expose the sector to extensive and continued carbon liability costs beyond mid-century and could be perceived as climate inaction, increasing reputational risks and the potential for less efficient regulatory interventions that could hinder sustainable tourism development. Effective tourism sector leadership is needed to develop a strategic tourism policy framework and emission measurement and reporting system.     

Perspectives on Natural Resources in the Global Economy: Polity Series Review

Polity's ‘Resources’ series is a set of scholarly books, each of them dealing with a single resource or resource‐based commodity from a generally global or international perspective. As of this writing, nine books have been published in the series, six of which I review here. The series is a welcome contribution to interdisciplinary and overall critical perspectives on the social and environmental dimensions and implications of the international appropriation, production and exchange of natural resources. While there is no clear disciplinary bent or theoretical foundation running across the volumes, together the books develop a transnational perspective, stressing the linkages between specific sites of appropriation and production, on the one hand, and broader political economic networks of processing, finance, coordination, commercial distribution and social regulation, on the other. The books should serve as valuable references to researchers in academic, government and non‐government institutional settings, but should also prove valuable for undergraduate teaching on contemporary natural resource industries and their social regulation.     

The contribution of social tourism to sustainable tourism: a case study of seasonally adjusted programmes in Spain

Recent policy from the European Union has attempted to justify social tourism initiatives on the basis that they lead to a more sustainable tourism industry. However, the majority of latest research in the field has been focused on the benefits for participants, with the addition of some evidence on the economic impacts of such programmes on destinations, which have pointed towards sustainability outcomes including: a longer tourism season, more even spread of demand, and longer periods of employment for tourism workers. Yet there is a lack of direct evidence linking such programme to these outcomes. This paper aimed to explore this important disconnect between policy assumptions and evidence-based outcomes through an analysis of the deseasonalising effects of the Spanish social tourism programme for older people. The research found that this programme does have an effect on the seasonal nature of employment and economic activity in most regions studied, but that the huge volume of demand from international tourists in the high seasons masks the quantitative effects in the regions with the highest seasonal concentration of international tourists. Recommendations for policy and practice in sustainable tourism are made that are transferable to many countries and regions that adopt social tourism programmes.     

Business models among SMTEs: identifying attitudes to environmental costs and their implications for sustainable tourism

This paper examines how environmental resources and costs feature in business models of small- and medium-sized tourism enterprises (SMTEs). Several studies have pointed to the generally positive nature of the relationship between the economic and environmental performance of tourism firms. Yet, although business models act as a vector between these aspects of firm performance, they have been overlooked in sustainable tourism discourse. The paper reports findings from discussion groups of SMTE businesses in South West England during the global economic downturn. Environmental costs and cost control were afforded relatively little importance in terms of value creation; conversely, there was a strong and predictable emphasis on revenue generation. Indirect tactics emerged for dealing with guests’ environmental behaviours which reflected this prevailing commercial logic. Green credentials were routinely de-emphasized, sometimes regarded as liabilities, in a form of greenhushing. Responses were framed by reference to social media and how online reviews may negatively impact on future value capture. Conceptually, the business model emerged as an important lens for understanding how environmental resources and costs were valourized. The paper highlights the need to ensure that contemporary approaches to environmental management in SMTEs reflect the current and fast-changing conditions that frame business models.     

Agrarian Change and the Initial Development of an Aboriginal Bourgeoisie in Australia

While the commercial ambitions of indigenous capitalists are continuously displayed in Australia, little is known about the origins and initial development of the class. In this essay one area of the country, the north‐west of Western Australia (WA), is chosen to show how changes in the principal agricultural industry opened space for Aboriginal commerce. Despite the opposition of State governments and existing firms that dominated cattle and sheep production, this space was enlarged as pastoralism underwent major changes. The rise of the indigenous bourgeoisie was also facilitated by the growing power of the class's political representatives in electoral and in executive politics. Parallel with changes in Australian federalism, which gave the national government increased financial and other powers, Aboriginal representatives captured this shift for commercial advantage.