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301.
The connections between people, parks, and tourism have received significant attention in recent years, recognizing the potential for mutually beneficial relationships. Ecotourism has been promoted and widely adopted as a strategy for funding conservation initiatives, while at the same time contributing to the socioeconomic development of host communities and providing for quality tourism experiences. Parks are among the most common ecotourism destinations. Employing interviews, observations and secondary sources, this study assesses the current status of ecotourism at two protected areas in Hainan, China, where it is being promoted as a strategy for balancing regional economic growth and conservation objectives. Through an evaluation of the existing tourism–park–community relationships, opportunities and constraints are identified. Ecotourism development was found to be at an early stage at both study sites. Socioeconomic benefits for the local communities have been limited and tourism activity has not contributed revenues towards conservation to date. Community residents, nevertheless, generally support conservation and are optimistic that tourism growth will yield benefits. In light of the study findings and the salient literature, planning direction is offered with the intention of enhancing the capacity of ecotourism to generate benefits for both communities and the parks, and thus contribute to the sustainable development of the region more generally. Lessons derived have broad applicability for ecotourism destinations elsewhere. 相似文献
302.
Slaton NA Brye KR Daniels MB Daniel TC Norman RJ Miller DM 《Journal of environmental quality》2004,33(5):1606-1615
Knowledge of the balance between nutrient inputs and removals is required for identifying regions that possess an excess or deficit of nutrients. This assessment describes the balance between the agricultural nutrient inputs and removals for nine geographical districts within Arkansas from 1997 to 2001. The total N, P, and K inputs were summed for each district and included inorganic fertilizer and collectable nutrients excreted as poultry, turkey, dairy, and hog manures. Nutrients removed by harvested crops were summed and subtracted from total nutrient inputs to calculate the net nutrient balance. The net balances for N, P, and K were distributed across the hectarage used for row crop, hay, pasture, or combinations of these land uses. Row-crop agriculture predominates in the eastern one-third and animal agriculture predominates in the western two-thirds of Arkansas. Nutrients derived from poultry litter accounted for >92% of the total transportable manure N, P, and K. The three districts in the eastern one-third of Arkansas contained 95% of the row-crop hectarage and had net N and P balances that were near zero or negative. The six districts in the western two-thirds of Arkansas accounted for 89 to 100% of the animal populations, had positive net balances for N and P, and excess P ranged from 1 to 9 kg P ha(-1) when distributed across row-crop, hay, and pasture hectarage. Transport of excess nutrients, primarily in poultry litter, outside of the districts in western Arkansas is needed to achieve a balance between soil inputs and removals of P and N. 相似文献
303.
Sharpe M 《Journal of environmental monitoring : JEM》2003,5(1):4N-9N
As the EU launches its latest 17 billion research programme, which includes significant funding for environmental research, JEM takes a look at the trends in and dynamics of innovation in environmental analysis. 相似文献
304.
Differences between inland and coastal aquacultural production systems in Asia are discussed in terms of market orientation, resource allocation and property rights, and scale of operations. The production of shrimp grown in coastal brackish water ponds has featured prominently in aquacultural development programmes in Asia. Emphasis placed on capital-intensive shrimp production for export, however, has distracted attention from the potential of inland freshwater aquaculture to generate employment opportunities for rural people and food production for domestic consumers. The paper concludes with a discussion of an alternative policy direction for promoting aquacultural development on a socially sound basis, recognizing the need to balance equity and human nutrition with profitability and foreign exchange earnings. 相似文献
305.
306.
Munang Tingem Mike Rivington 《Mitigation and Adaptation Strategies for Global Change》2009,14(2):153-168
The Cameroonian agricultural sector, a critical part of the local ecosystem, is potentially vulnerable to climate change raising
concerns about food security in the country’s future. Adaptations policies may be able to mitigate some of this vulnerability.
This article investigates and addresses the issue of selected adaptation options within the context of Cameroonian food production.
A methodology is applied where transient diagnostics of two atmosphere–ocean general circulation models, the NASA/Goddard
Institute GISS and the British HadCM3, are coupled to a cropping system simulation model (CropSyst) to simulate current and
future (2020, 2080) crop yields for selected key crops (bambara nut, groundnut, maize, sorghum, and soybean) in eight agricultural
regions of Cameroon. Our results show that for the future, substantial yield increases are estimated for bambara groundnut,
soybean and groundnut, while little or no change or even decreases for maize and sorghum yields, varying according to the
climate scenario and the agricultural region investigated. Taking the “no regrets” principle into consideration, we explore
the advantages of specific adaptation strategies specifically for three crops viz. maize, sorghum and bambara groundnut, under
GISS A2 and B2 marker scenarios only. Changing sowing dates may be ineffective in counteracting adverse climatic effects because
of the narrow rainfall band that strictly determines the timing of farm operations in Cameroon. In contrast, the possibility
of developing later maturing new cultivars proved to be extremely effective in offsetting adverse impacts, giving the highest
increases in productivity under different scenario projections without management changes. For example, under climate change
scenario GISS A2 2080, a 14.6% reduction in maize yield was converted to a 32.1% increase; a 39.9% decrease in sorghum yield
was converted to a 17.6% increase, and for bambara groundnut (an under-researched and underutilised African legume), yields
were almost trebled (37.1% increase above that for sowing date alone (12.9%)) due to increase length of growing period and
the positive effects of higher CO2 concentrations. These results may better inform wider studies and development strategies on sustainable agriculture in the
area by providing an indication as to the potential direction in shifts in production capabilities. Our approach highlights
the benefit of using models as tools to investigate potential climate change impacts, where results can supplement existing
knowledge. The results provide useful guidance and motivation to public authorities and development agencies interested in
food security issues in Cameroon and elsewhere. 相似文献
307.
Kees Jan van Groenigen Astley Hastings Dermot Forristal Brendan Roth Mike Jones Pete Smith 《Agriculture, ecosystems & environment》2011,140(1-2):218-225
Soil tillage and straw management are both known to affect soil organic matter dynamics. However, it is still unclear whether, or how, these two practices interact to affect soil C storage, and data from long term studies are scarce. Soil C models may help to overcome some of these problems. Here we compare direct measurements of soil C contents from a 9 year old tillage experiment to predictions made by RothC and a cohort model. Soil samples were collected from plots in an Irish winter wheat field that were exposed to either conventional (CT) or shallow non-inversion tillage (RT). Crop residue was removed from half of the RT and CT plots after harvest, allowing us to test for interactive effects between tillage practices and straw management. Within the 0–30 cm layer, soil C contents were significantly increased both by straw retention and by RT. Tillage and straw management did not interact to determine the total amount of soil C in this layer. The highest average soil C contents (68.9 ± 2.8 Mg C ha?1) were found for the combination of RT with straw incorporation, whereas the lowest average soil C contents (57.3 ± 2.3 Mg C ha?1) were found for CT with straw removal. We found no significant treatment effects on soil C contents at lower depths. Both models suggest that at our site, RT stimulates soil C storage largely by decreasing the decomposition of old soil C. Extrapolating our findings to the rest of Ireland, we estimate that RT will lead to C mitigation ranging from 0.18 to 1.0 Mg C ha?1 y?1 relative to CT, with the mitigation rate depending on the initial SOC level. However, on-farm assessments are still needed to determine whether RT management practices can be adopted under Irish conditions without detrimental effects on crop yield. 相似文献
308.
David W. Gibbons Chris Sandbrook William J. Sutherland Rezvin Akter Richard Bradbury Steven Broad Andy Clements Humphrey Q. P. Crick Joanna Elliott Ngawang Gyeltshen Melanie Heath Jonathan Hughes Richard K. B. Jenkins Alastair H. Jones Rocio Lopez de la Lama Nicholas B. W. Macfarlane Mike Maunder Ravikash Prasad Alfredo Romero-Muñoz Noa Steiner James Tremlett Rosie Trevelyan Savita Vijaykumar Irushinie Wedage Nancy Ockendon 《Conservation biology》2022,36(1):e13781
The COVID-19 pandemic has had an enormous impact on almost all aspects of human society and endeavor; the natural world and its conservation have not been spared. Through a process of expert consultation, we identified and categorized, into 19 themes and 70 subthemes, the ways in which biodiversity and its conservation have been or could be affected by the pandemic globally. Nearly 60% of the effects have been broadly negative. Subsequently, we created a compendium of all themes and subthemes, each with explanatory text, and in August 2020 a diverse group of experienced conservationists with expertise from across sectors and geographies assessed each subtheme for its likely impact on biodiversity conservation globally. The 9 subthemes ranked highest all have a negative impact. These were, in rank order, governments sidelining the environment during their economic recovery, reduced wildlife-based tourism income, increased habitat destruction, reduced government funding, increased plastic and other solid waste pollution, weakening of nature-friendly regulations and their enforcement, increased illegal harvest of wild animals, reduced philanthropy, and threats to survival of conservation organizations. In combination, these impacts present a worrying future of increased threats to biodiversity conservation but reduced capacity to counter them. The highest ranking positive impact, at 10, was the beneficial impact of wildlife-trade restrictions. More optimistically, among impacts ranked 11-20, 6 were positive and 4 were negative. We hope our assessment will draw attention to the impacts of the pandemic and, thus, improve the conservation community's ability to respond to such threats in the future. 相似文献