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961.
962.
Vo Thi Thanh Loc Simon R. Bush Le Xuan Sinh Nguyen Tri Khiem 《Environment, Development and Sustainability》2010,12(6):889-908
This paper investigates the structure, function and wealth distribution within the Pangasius hypophthalmus and Henicorhynchus spp./Labiobarbus spp. value chains in the Mekong Delta of Vietnam. The analysis is driven by key questions relating to the form and function
of value chains, their contribution to the livelihoods of farmers and fishers, the effectiveness of government policy and
the potential for value chain governance mechanisms, such as contracts and certification, to steer towards sustainable production.
The results indicate that actors in the high value Pangasius hypopthalmus export chain have a higher potential income, but face considerably higher economic vulnerability from global markets. Alternatively,
Henichorhychus/Labiobarbus spp. fishers are severely constrained in their ability to negotiate higher prices for their fish but appear to be less vulnerable
to economic and environmental change. The paper concludes that for value chain governance to improve the livelihoods of fishers
and farmers in both high and low value chains, new arrangements are needed that better accommodate customary institutions
and informal market relations. 相似文献
963.
Developed countries are major markets for developing country fresh produce. Demand by developed country consumers for spotless
produce has encouraged developing country consumers to rely increasingly on pesticides in producing fresh export vegetables.
However developed country pesticide standards enacted in response to reports of increased farmer and farm worker pesticide
poisoning and the food safety scandals of the 1980s and 1990s require changes in the way growers use pesticides. The EU has
especially developed stringent food safety standards relating to, among other things, pesticide usage. Under EU pesticide
standards (EU-PS) farmers are trained by their buyers on safe use of pesticides and then closely monitored under contract.
This paper looks at the impact of these standards on developing country farmers’ use of alternative pest management practices,
pesticide protective clothing and the actual usage of pesticides. It finds that compliance with EU-PS increases the use of
alternative pest management practices and protective clothing. However, EU-PS has mixed effect on the quantity of pesticides
used. The paper also finds that farmer’s education and access to information play an important role in the use of alternative
pest management practices. The paper concludes that EU-PS encourage the use of alternative pest management practices and pesticide
protective gear in production of fresh export vegetables. The findings imply that EU-PS promote environmentally-friendly methods
of production of fresh export vegetables in developing countries. 相似文献
964.
965.
J. Ram Pillarisetti Jeroen C. J. M. van den Bergh 《Environment, Development and Sustainability》2010,12(1):49-62
What is a ‘sustainable nation’ and how can we identify and rank ‘sustainable nations?’ Are nations producing and consuming in a sustainable way? Although several aggregate indexes have been proposed to answer such questions, comprehensive and internationally comparable data are not available for most of these. This paper quantitatively compares three aggregate indexes of sustainability: the World Bank’s ‘Genuine Savings’ measure, the ‘Ecological Footprint,’ and the ‘Environmental Sustainability Index.’ These three indexes are available for a large number of countries and also seem to be the most influential among the aggregate indexes. This paper first discusses the main limitations and weaknesses of each of these indexes. Subsequently, it shows that rankings of sustainable nations and aggregate assessments of unsustainable world population and world GDP shares vary considerably among these indexes. This disagreement leads to suggestions for analysis and policy. One important insight is that climate change, arguable the most serious threat currently faced by humanity, is not or arbitrarily captured by the indexes. 相似文献
966.
Exporting natural capital: the foreign eco-footprint on Costa Rica and implications for sustainability 总被引:1,自引:0,他引:1
As the world economy ‘globalizes’, trade has become a major mechanism by which much of the human population supports its needs.
While trade in resource commodities (natural income) can increase the well-being of people in both exporting and importing
countries, it can also lead to depletion of natural capital and the loss of ecosystems integrity. In recent years, various
researchers have attempted to address this problem using a consumption-based perspective on ecological change. Their work
shows that the loss of ecosystem integrity in almost any region of the world can be attributed to both local and international
consumer demand. This paper illustrates the utility of modified eco-footprint analysis in assessing export-related ecological
change in Costa Rica. We quantify ecological footprint of consumers around the world on the productive ecosystems of Costa
Rica, document the changing character of this footprint and highlight some of the linkages between production for export in
Costa Rica and ecological degradation. We then discuss the implications of the increasing trade-based entanglement of nations
for ecosystems and global sustainability. 相似文献
967.
Kris A. G. Wyckhuys Robert J. O’Neil 《Environment, Development and Sustainability》2010,12(3):297-311
In subsistence farming systems of the developing world, adoption of resource-conserving practices such as integrated pest
management (IPM) is often strikingly low. This has partially been ascribed to researchers’ limited understanding of how technologies
develop at the interface of the systems’ social and ecological components. In Honduras (Central America), there exists concern
about limited adoption and diffusion of IPM technologies in certain smallholder production systems. In this study, we determine
social and ecological drivers of IPM adoption in subsistence maize production in the country’s hillside environment. Honduran
small-scale maize production is typified by a key insect pest (the fall armyworm, Spodoptera frugiperda) being partly kept at bay through action of a diverse natural enemy complex, including ants, social wasps, carabid beetles,
and spiders. Local agricultural landscapes, primarily shaped through shifting cultivation, provide key resources to maintain
this natural enemy diversity. These local ecological conditions and related natural enemy abundance strongly influence farmers’
agroecological knowledge and pest management practices. In the meantime, farmer practices are also affected by local communication
networks, which help validate and spread IPM concepts and technologies. Based on our findings, we advocate a holistic approach
to improve IPM extension through mapping of agroecological opportunities, visualization of regional patterns in farmer knowledge,
and associated priority setting. Local IPM capacity could be built through institutional strengthening and adaptive comanagement,
while IPM training should be linked with natural resource management initiatives. These approaches may eventually improve
the way IPM is delivered to small-scale farmers who operate in the ecologically diverse environments of the tropics. 相似文献
968.
The abundance of terrestrial arthropods in the Orenburgskii Nature Reserve has decreased since its establishment in 1989.
At present, this parameter fluctuates considerably, and the species composition of arthropods is changing in favor of xerobiontic
and eurybiontic species. These changes result from the absence of grazing load as well as from periodic fires. Therefore,
it is necessary to organize controlled livestock grazing and reliable fire protection in reserved areas. 相似文献
969.
Z. G. Prishutova 《Russian Journal of Ecology》2010,41(1):55-59
Vegetation was considerably trampled throughout Vodnyi Island in the Rostovskii Nature Reserve in 2007 because of a high pasture
load due to feral horses (0.15 horses/ha). Calculation of the food resources on the island, with its protection as part of
a nature reserve taken into account, has shown that the herd size is 3.5 times larger than the maximum allowable value. 相似文献
970.
V. N. Orlov Yu. M. Borisov S. Yu. Irkhin A. A. Kovaleva 《Russian Journal of Ecology》2010,41(6):519-523
The distribution of three chromosome races (Moscow, Western Dvina, and Seliger) of the common shrew Sorex araneus L. in the zone of contact between their ranges in the Valdai Heights (32°00′ E, 57°00′ N) is discussed. The area co-inhabited
by all the three races is extremely small. Representatives of all the three races have been captured on only one trap line,
although there are no obstacles to the expansion of shrews. The extremely small area co-inhabited by the three races, as well
as the strictly parapatric distribution of the Moscow and Western Dvina races, may be related with competition forms such
as avoidance of contacts and separation of ecological niches. 相似文献