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991.
According to various reports, climate change is responsible for the change in rainfall amount and pattern accompanied by the
various degrees of extreme events in Sahelian West Africa in recent years. Other reports also suggest that there has been
a “recovery” of the rainy season (Nicholson 2005). In this study, temporal characteristics of meteorological droughts in the Volta basin, a semi-arid region in West Africa,
are investigated in order to provide a guide for sustainable water resource management. For this purpose, drought intensity,
areal extent and recurrence frequency is analysed using the standardised precipitation index (SPI) for a time series between
1961 and 2005 from 52 meteorology stations across the Volta basin. Using this analysis the severity of the historical droughts
of 1961, 1970, 1983, 1992 and 2001 that occurred in the region are assessed and their intensity, areal extent and return periods
are obtained. The drought intensity is lower than −2.0 over nearly 75% of the region, meaning that a major part of the region
was under extreme drought conditions during this year. The drought of 1983/1984 has a probability of occurrence of up to 0.1
from records spanning 44 years. The areal extent of extreme drought conditions is about 90% during this drought period. 相似文献
992.
Renewable energy is considered an indispensable basis of sustainable energy systems as electricity generation from renewable
sources results in low emissions of greenhouse gases compared to fossil fuel based electricity and contributes to sustainable
development. However, effective strategies and conducive institutional settings are needed for advancement of such clean electricity
systems. Although Thailand, as a nation, has a huge potential for renewable energy utilization, its total amount of electricity
generation from renewables is relatively small and could be enlarged substantially. Lack of policy mechanisms, institutional
development and financing exist as major barriers for Thailand in this regard. Investigation of the nation’s current energy
strategy implementation shows that relevant energy and development policies are at different stages of implementation and
institutional settings are continuously evolving. This paper argues that further significant efforts could be made towards
advancement of renewable electricity and thus achievement of energy sustainability in Thailand. Resource planning, effective
policy and institutions, focussed planning for energy sustainability and implementation of the Clean Development Mechanism
(CDM) under the Kyoto Protocol could facilitate further advancement of renewables for the nation. 相似文献
993.
994.
Sex-biased predation is thought to have important implications for sexual selection, sex allocation, and population dynamics (Magnhagen, 1991; Le-Galliard et al., 2005 for an example in lizards). Most studies found that males are subjected to higher predation pressure than females during the reproductive season (Korpimäki, 1985; Lodé et al., 2004; Christe et al., 2006; Costantini et al., 2007). In that period, males are very mobile, emit acoustic signals and exhibit brilliant colourations, which are needed to attract females but may make them more visible to predators. With regard to lizards, a recent study provided the first evidence that males of a lizard species may be preyed on more than females (Costantini et al., 2007). In the present study, we investigated whether there is sex-biased predation on two small lacertid species, the common wall lizard Podarcis muralis (Laurenti, 1768) and the Italian wall lizard Podarcis sicula (Rafinesque-Schmaltz, 1810), by Eurasian kestrels (Falco tinnunculus) during the reproductive season. We also examined whether (1) the rate of predation differed between species and (2) the rate of predation differed across years or among hunting habitats for each species. 相似文献
995.
996.
Hong Wang 《Environment, Development and Sustainability》2010,12(4):481-490
Under the current situation of environmental pollution and resources shortage, the research of corporate environmental responsibility
(CER) is of great importance to promote the sustainable development of society. The article adopts the perspective of the
Stakeholder Theory and environmental management to make the empirical analysis of CER. Consequently designed questionnaire
investigation is carried out among 30 Shanghai enterprises during 2007 and 2008. Through the correlation analysis, principal
component analysis, factor ordering, and variables reappearance of key factors, seven key indexes are identified in the original
35 variables. This article aims to provide reference for enterprise environmental management and forwards the study of Corporate
Social Responsibility. 相似文献
997.
Alexandros Flamos 《Environment, Development and Sustainability》2010,12(1):89-102
The (usually not professed) truth is that we are not destroying the planet due to lack of technology, but due to lack of application
of technology. Indeed, opportunities exist for renewable energy technologies’ diffusion under the new climate change regime
as they contribute to global sustainability through GHG mitigation and, they conform to national priorities by leading to
the enhancement of local economic activity, capacities and infrastructure. The clean development mechanism (CDM), although
is considered one of the global policy tools to contribute to sustainable development and technology transfer, has recently
been criticised for its unequal distribution of projects across countries and for insufficiently being embedded in developing
countries’ national energy context. In the above framework, this article presents the ENTTRANS approach, five indicative renewable
energy technologies, and insights about a more effective application of CDM, which may be part of the international process
striving towards sustainable development. 相似文献
998.
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
999.
Uchechukwu Ugwuh Solomon 《Environment, Development and Sustainability》2010,12(6):1069-1080
Campaigns to mitigate environmental degradation problems have failed in recent years due to not only the inability to identify
the actual causes of the problems but also the approach followed in addressing these problems. This study gives a detailed
consideration to the roles played by environmental education, ethics and law in environmental enhancement and protection with
the aim of identifying the one that has made the most progress toward reducing the impact of environmental problems. Knowledge
of this is necessary as it will help determine the starting point of any environmental sustainability campaign and direct
efforts toward this. The findings of this study show that the importance of the three disciplines in environmental enhancement
and protection cannot be over-looked, and it identifies environmental ethics as both an interconnector of the other two disciplines
and the force that propels them into action. 相似文献
1000.
Pinus roxburghii (chir-pine) and Quercus leucothchophora (banj-oak) are dominant forests of mountainous part of the Uttarakhand Himalaya. The continued anthropogenic disturbance
is opening the canopy, forming canopy gaps and as a result forest fragments are developing. Thus, the present study aims to
analyze variations in species richness and vegetational parameters in relation to canopy gaps in forests. Total species richness
was greater in open canopied forest compared to moderate and close canopied forests. In comparison between oak and pine forest,
it was greater in oak forest while the proportion of common species was low between oak—pine forests. Mean species richness
did not significantly vary from one canopy gap to another as well as in oak and pine dominated forest. This indicated that
dominant forest types played an important role to form the community structure. The shrubs richness were greater in closed
canopy and between the forests it was greater in pine forest. Tree and shrub density was low in open canopy while herb density
was high in moderate canopy. Thus, this study indicated that the dominant canopy species play an important role in deciding
the community structures especially the distribution of under canopy species. These parameters should be considered for conservation
and maintenance of plant biodiversity of a region. 相似文献