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121.
122.
The Impact of Land-Use Change on Ecosystem Services,Biodiversity and Returns to Landowners: A Case Study in the State of Minnesota 总被引:13,自引:1,他引:12
Stephen Polasky Erik Nelson Derric Pennington Kris A. Johnson 《Environmental and Resource Economics》2011,48(2):219-242
Land-use change has a significant impact on the world’s ecosystems. Changes in the extent and composition of forests, grasslands,
wetlands and other ecosystems have large impacts on the provision of ecosystem services, biodiversity conservation and returns
to landowners. While the change in private returns to landowners due to land-use change can often be measured, changes in
the supply and value of ecosystem services and the provision of biodiversity conservation have been harder to quantify. In
this paper we use a spatially explicit integrated modeling tool (InVEST) to quantify the changes in ecosystem services, habitat
for biodiversity, and returns to landowners from land-use change in Minnesota from 1992 to 2001. We evaluate the impact of
actual land-use change and a suite of alternative land-use change scenarios. We find a lack of concordance in the ranking
of baseline and alternative land-use scenarios in terms of generation of private returns to landowners and net social benefits
(private returns plus ecosystem service value). Returns to landowners are highest in a scenario with large-scale agricultural
expansion. This scenario, however, generated the lowest net social benefits across all scenarios considered because of large
losses in stored carbon and negative impacts on water quality. Further, this scenario resulted in the largest decline in habitat
quality for general terrestrial biodiversity and forest songbirds. Our results illustrate the importance of taking ecosystem
services into account in land-use and land-management decision-making and linking such decisions to incentives that accurately
reflect social returns. 相似文献
123.
Industry changes in technology and complementary assets and the creation of high-growth firms 总被引:1,自引:0,他引:1
This study uses employment data to examine why some industries host more new high-growth firms than others. Using a unique data base of 201 industries over a 15-year period, we find that increases in the proportion of employment of scientists and engineers in industries are positively associated with counts of fast-growing new firms; however, we do not detect a relationship between fluctuations in the proportion of employment in sales and production occupations and counts of fast-growing new firms. The findings suggest that technological innovation is an important determinant of entrepreneurial opportunity. Further, they suggest that private new firms are an important means of organizing commercial innovation and that new firms may be less constrained by complementary assets than has been previously understood. 相似文献
124.
125.
This study examines the perceived usefulness of alternative spatial and tree-based similarity scaling techniques in a market analysis task. These techniques are typically evaluated on their ability to fit or explain customer input data. The psychological reaction of individuals who use these techniques to analyze markets has been largely ignored. The study reveals that spatial representations are perceived as more useful than tree-based clustering techniques, even though the latter provide a better fit to customer perceptions. The results have implications for both the use and development of scaling techniques in psychology and marketing. © 1996 John Wiley & Sons, Inc. 相似文献
126.
Investment in soil conservation in northern Ethiopia: the role of land tenure security and public programs 总被引:5,自引:0,他引:5
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. 相似文献
127.
Fertilizer Demand in China's Reforming Economy 总被引:5,自引:0,他引:5
128.
推广转基因抗虫棉对次要害虫农药施用的影响分析 总被引:3,自引:0,他引:3
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。 相似文献
129.
José David Cisneros-Martínez Scott McCabe Antonio Fernández-Morales 《Journal of Sustainable Tourism》2018,26(1):85-107
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. 相似文献
130.
Azar Kafashpor Seyedeh Fatemeh Ghasempour Ganji Samaneh Sadeghian Lester W. Johnson 《Asia Pacific Journal of Tourism Research》2018,23(6):521-531
Tourism development affects various aspects of a populace’s life, such as environmental, social, economic, and other areas. This study examines the effect of perceived tourism development on subjective happiness and quality of life among residents of Mashhad City, Iran. A sample size of 384 residents completed a survey. Data analysis was performed using WarpPLS. Results indicated that tourism development had an effect on the residents’ subjective happiness and quality of life (QOL) and the effects of social and micro economic factors on the residents’ subjective happiness and the effects of cultural, environmental, and macroeconomic factors on the resident’s QOL. 相似文献