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841.
The eastern Mediterranean and Middle East, a region with diverse socioeconomic and cultural identities, is exposed to strong climatic gradients between its temperate north and arid south. Model projections of the twenty-first century indicate increasing hot weather extremes and decreasing rainfall. We present model results, which suggest that across the Balkan Peninsula and Turkey climate change is particularly rapid, and especially summer temperatures are expected to increase strongly. Temperature rise can be amplified by the depletion of soil moisture, which limits evaporative cooling, prompted by the waning of large-scale weather systems that generate rain. Very hot summers that occurred only rarely in the recent past are projected to become common by the middle and the end of the century. Throughout the region, the annual number of heat wave days may increase drastically. Furthermore, conditions in the region are conducive for photochemical air pollution. Our model projections suggest strongly increasing ozone formation, a confounding health risk factor particularly in urban areas. This adds to the high concentrations of aerosol particles from natural (desert dust) and anthropogenic sources. The heat extremes may have strong impacts, especially in the Middle East where environmental stresses are plentiful.  相似文献   
842.
Identifying effective adaptation strategies for coastal communities dependent on marine resources and impacted by climate change can be difficult due to the dynamic nature of marine ecosystems. The task is more difficult if current and predicted shifts in social and economic trends are considered. Information about social and economic change is often limited to qualitative data. A combination of qualitative and quantitative models provide the flexibility to allow the assessment of current and future ecological and socio-economic risks and can provide information on alternative adaptations. Here, we demonstrate how stakeholder input, qualitative models and Bayesian belief networks (BBNs) can provide semi-quantitative predictions, including uncertainty levels, for the assessment of climate and non-climate-driven change in a case study community. Issues are identified, including the need to increase the capacity of the community to cope with change. Adaptation strategies are identified that alter positive feedback cycles contributing to a continued decline in population, local employment and retail spending. For instance, the diversification of employment opportunities and the attraction of new residents of different ages would be beneficial in preventing further population decline. Some impacts of climate change can be combated through recreational bag or size limits and monitoring of popular range-shifted species that are currently unmanaged, to reduce the potential for excessive removal. Our results also demonstrate that combining BBNs and qualitative models can assist with the effective communication of information between stakeholders and researchers. Furthermore, the combination of techniques provides a dynamic, learning-based, semi-quantitative approach for the assessment of climate and socio-economic impacts and the identification of potential adaptation strategies.  相似文献   
843.
Animal fleshing (ANFL) is the predominant proteinaceous solid waste generated during processing of leather and it is confronting disposal problems. The aim of this study was to assess the potential of epigeic earthworm Eudrilus eugeniae to utilize and transform the fermented ANFL in the solid state (SSF) and submerged state (SmF) into a value added product along a low residence period (25 days). A total of six treatment units containing different waste mixture compositions were established. Fifty healthy and non-clitellated earthworms were introduced in three different treatment containers: control, SSF, and SmF (+worm). Another set of treatment mixtures (control, SSF, SmF) was established without earthworms (?worm) to compare the results. The products were characterized for physico-chemical, enzymatic analysis and seedling growth parameters to compare the differences in the process with and without earthworms. The changes observed in the analytical parameters were in the following order: SSF > SmF > control mixtures (p?<?0.05). The vermicompost showed a significant reduction in heavy metals, total organic carbon and an increase in total Kjeldhal nitrogen as compared to the product untreated by earthworms. The maximum enzymatic activities were observed after 21 days of vermicomposting. The relative seed germination of vermicompost extracts were in the order of tomato (Lycopersicon esculentum) > green gram (Vigna radiata) > cucumber (Cucumis sativus) > bottle gourd (Lagenaria siceraria (Mol.) Standl.) and showed no phytotoxicity effects. The results indicated that the combination of both ANFL hydrolysis through fermentation and vermicomposting is a good alternative to the management of this kind of waste.  相似文献   
844.
The Australian and New Zealand Guidelines for Fresh and Marine Water Quality are a key document in the Australian National Water Quality Management Strategy. These guidelines released in 2000 are currently being reviewed and updated. The revision is being co-ordinated by the Australian Department of Sustainability, Environment, Water, Population and Communities, while technical matters are dealt with by a series of Working Groups. The revision will be evolutionary in nature reflecting the latest scientific developments and a range of stakeholder desires. Key changes will be: increasing the types and sources of data that can be used; working collaboratively with industry to permit the use of commercial-in-confidence data; increasing the minimum data requirements; including a measure of the uncertainty of the trigger value; improving the software used to calculate trigger values; increasing the rigour of site-specific trigger values; improving the method for assessing the reliability of the trigger values; and providing guidance of measures of toxicity and toxicological endpoints that may, in the near future, be appropriate for trigger value derivation. These changes will markedly improve the number and quality of the trigger values that can be derived and will increase end-users’ ability to understand and implement the guidelines in a scientifically rigorous manner.  相似文献   
845.
In modern living, rapid development has created an increase in demand for groundwater. An endeavor has been made to understand the hydrogeochemical parameters to determine the utility of groundwater. This situation is severe in coastal hard rock aquifers due to the influence of salinity ingression and other anthropogenic influence. A total of 135 groundwater samples were collected from the coastal aquifer of the Tuticorin district and analyzed for major cations and anions during premonsoon (PRM) and postmonsoon (POM). The ions analyzed were used to determine the drinking, agricultural and domestic utility of groundwater. The electrical conductivity (EC) contour shows that the groundwater quality is poor along the coast. The parameters were compared with WHO (Guidelines for drinking water quality recommendations, WHO, Geneva, 2004) standard for drinking purpose. A groundwater classification method has been developed for groundwater in the area using a dynamic water quality index (WQI). On the basis of the WQI so computed, groundwater in the area has been spatially classified into “excellent,” “good,” “poor” and “very poor” to “Unsuitable” water types variation lithologywise. Corrosivity ratio and hardness were noted to be higher and found to be unsuitable in majority of the regions for domestic purpose. Higher fluoride concentration was noted in the central part of the study area represented by complex geology comprising of the hornblende biotite gneiss and charnockite. Sodium percentage (Na%), sodium absorption ratio, residual sodium carbonate, Wilcox (Classification and use of irrigation waters, US Department of Agriculture, Washington, 1955), permeability index, residual sodium bicarbonate, magnesium hazard, Kelly’s ratio and potential salinity also indicate that most of the groundwater samples are not suitable for irrigation purposes.  相似文献   
846.
Future climate conditions are likely to affect inland waterway transport in Europe. According to some climate scenarios, in summer, in the river Rhine, periods with low water levels are likely to occur more often and become more serious. Then inland waterway transport carriers will experience more severe restrictions on the load factor of their inland ships, which implies a stronger reduction in transport capacity in the market. Transport prices will rise under such conditions. Some studies reviewed in this paper find that at extremely low water levels, the price per tonne for inland waterway transport in the river Rhine area will almost double. These increased transport prices result in welfare losses. For the dry summer in 2003, the losses for North West Europe are estimated to sum up to around €480 million. Increased transport prices trigger adaptation. Inland waterway carriers may use smaller vessels, and shippers have the opportunity to shift from inland waterway transport to alternative transport modes in periods with low water levels. This effect is probably rather modest, however, with a modal shift to road and rail smaller than 10 %. Also, changes in transport costs may lead to relocation of certain economic activities in the long run.  相似文献   
847.
The ecosystem services framework is receiving increasing attention in the fields of policy and research. The assessment of human attitudes and perceptions regarding ecosystem services has been proposed as a promising tool for addressing complex problems associated with environmental change, particularly in the context of cultural landscapes. Transhumance is not only a farming practice responsible for shaping cultural landscapes but also an adaptive strategy based on mobility that may represent a useful approach to overcoming the growing challenges posed by accelerated environmental change. A socio-cultural valuation of ecosystem services associated with the Conquense Drove Road, one of the major transhumant networks still in use in Mediterranean Spain, was conducted via the distribution of questionnaires to 416 local residents and visitors to capture their perceptions regarding the importance of 34 ecosystem services (10 provisioning, 12 regulating, and 12 cultural) for both social and personal well-being. Overall, the ecosystem services considered to be the most important for social well-being were fire prevention, air purification and livestock. Most of the ecosystem services in question were perceived as declining, with the exception of those associated with recreation, scientific knowledge and environmental education. This study revealed that perceptions regarding the value of ecosystem services differed among respondents, depending on their age, place of origin and gender. Several methodological issues, as well as the implications of socio-cultural valuation for policy making, are also discussed here.  相似文献   
848.
This paper examines the size and intensity of changes among five land categories during the two time intervals in a region of Indonesia that is pioneering negotiations concerning reducing emissions from deforestation and forest degradation (REDD). Maps at 1973, 1993, and 2005 indicate that land-cover change is accelerating, while carbon loss is decelerating in Jambi Province, Sumatra. Land dynamics have shifted from Forest loss during 1973–1993 to Agroforest loss during 1993–2005. Forest losses account for most reductions in aboveground carbon during the both time intervals, but Agroforest plays an increasingly important role in carbon reductions during the more recent interval. These results provide motivation for future REDD policies to count carbon changes associated with all influential land categories, such as Agroforests.  相似文献   
849.
Public engagement and support is essential for ensuring adaptation to climate change. The first step in achieving engagement is documenting how the general public currently perceive and understand climate change issues, specifically the importance they place on this global problem and identifying any unique challenges for individual communities. For rural communities, which rely heavily on local agriculture industries, climate change brings both potential impacts and opportunities. Yet, to date, our knowledge about how rural residents conceptualise climate change is limited. Thus, this research explores how the broader rural community—not only farmers—conceptualises climate change and responsive activities, focussing on documenting the understandings and risk perceptions of local residents from two small Australian rural communities. Twenty-three semi-structured interviews were conducted in communities in the Eden/Gippsland region on the border of New South Wales and Victoria and the north-east of Tasmania. There are conflicting views on how climate change is conceptualised, the degree of concern and need for action, the role of local industry, who will ‘win’ and ‘lose’, and the willingness of rural communities to adapt. In particular, residents who believed in anthropogenic or human-induced factors described the changing climate as evidence of ‘climate change’, whereas those who were more sceptical termed it ‘weather variability’, suggesting that there is a divide in rural Australia that, unless urgently addressed, will hinder local and national policy responses to this global issue. Engaging these communities in the twenty-first-century climate change debate will require a significant change in terminology and communication strategies.  相似文献   
850.
Leaves of Tendergreen bean plants exposed to atmospheric fluoride concentrations in the range 1.7 to 7.6 μg/m3 showed increased levels of enolase and catalase activity and decreased levels of pyruvate and α-ketoglutarate. Phosphoenolpyruvate carboxylase activity and oxalacetate were not affected. The leaves of Milo maize plants exposed to 5.0 μg F/m3 showed increased levels of enolase and pyruvate kinase activity and a decreased level of pyruvate. Oxalacetate and α-ketoglutarate levels were not affected. Catalase activity was increased, then decreased by IIF fumigation. The changes induced by HF were greatest six to 10 days after the start of fumigation and disappeared or decreased in magnitude during the post-fumigation period.  相似文献   
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