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671.
Climate adaptation is a complex task surrounded by uncertainty. To support climate adaptation policies, a new scenario approach is pursued to explore possible discontinuous future developments of societal perspectives on climate adaptation issues. The scenario approach was tested for a case study on Dutch river management. In a series of scenario development workshops, a select group of stakeholders explored the perspectives on the management of the River Meuse in the past, present, and future. The process was supported by an analytical perspectives mapping tool to illustrate and analyze the development of perspectives over time. The process and analytical tools contributed to insight into the drivers of perspective change for the case study at hand. Moreover, the stakeholders highlighted the potential of the approach for water management policy for creating awareness about the plurality of perspectives and the dynamics of perspective change, monitoring perspectives and perspective change as part of a flexible policy approach, and anticipating on the occurrence of shock events. Further work is required to better represent the social dynamics of perspectives change, to better empirically ground the perspective change model, and to apply integrated water models in the scenario development process to assess water–society interactions.  相似文献   
672.
The states of the populations of five dominant species of predatory mammals living in the area affected by the Kalinin Nuclear Power Plant (NPP) and in remote districts of Tver’ oblast have been compared. A total of 1120 skulls, including 708 skulls from the vicinity of the NPP, have been examined. The data on parameters characterizing similarities between the samples, the degree and structure of intrapopulation diversity, and ontogenetic stability suggest with a high probability that the Kalinin NPP has no effect on wild populations of predatory mammals.  相似文献   
673.
The use of an extended set of basic characteristics of the terrain topography for studying the spatial variation of a forest ecosystem has shown that it is significantly related to the terrain topography. The relationships with the topographic attributes determining the local hydrological and thermal conditions in the ecosystem has been paid special attention. Maps of ecosystem characteristics based on the observed relationships with topography have been calculated and drawn.  相似文献   
674.
The developing countries i.e., the non-Annex-I countries (parties to the Kyoto Protocol but not responsible to any reduction target yet) in the Kyoto Protocol whose economies are in transition are also allowed to reduce GHG emissions. Among these, the countries that have accepted the Kyoto Protocol may be benefited from CDM projects to promote sustainable development. The developed countries i.e., the Annex-I countries (that have signed the Kyoto Protocol & are responsible to have specific GHG emission reduction target) or the investing countries, in return, have privilege to purchase CER credits (in units equivalent to one tonne of CO2 gas emission reduction) to meet the emission target as specified in the Kyoto Protocol. The key step in understanding about CDM is to grasp the concept of “baseline” and “additionality”. The “Baseline” is the emissions level that would have existed if a CDM project had not happened. The feature of an approved CDM project is that the planned reductions would not occur without the additional incentive provided by emission reduction credits; this concept is known as “Additionality”. According to environmental additionality concept, baseline emission minus project emission is equal to emissions reduction. “Investment Additionality,” ultimately rejected during negotiation of the “Marrakech Accords” and “Financial Additionality,” are the two important concepts. The concept of trading of CER matches to the idea of Pigovian tax (equal to the negative externality and which is considered one of the “traditional” means of bringing a modicum of market forces) in Economics, making pollution more costly to the polluter, as the polluters have negative cost since they save money by polluting; hence, there are supposed negative externalities associated with the market activity. Economic theory predicts that in an economy where the cost of reaching mutual agreement between parties is high and where pollution is diffuse, Pigovian tax will be an efficient way to promote the public interest and will lead to an improvement of the quality of life measured by the Genuine Progress Indicator and other human economic indicators, as well as higher gross domestic product growth. We can seek a level of pollution such that the marginal savings (MS) to one polluting unit from pollution (−MC) is equal to marginal damage (MD) from pollution over the entire population, since pollution is a public bad i.e., MS (x*) = ∑MDi (x*) where ∑Di (x) is the total damage. Though the responsibility of reduction in emission does not lie on the non-Annex-I countries, still effort of maintaining global emission balance can be expected equally from developed and developing countries. The responsibilities of Kyoto Protocol are (a) to reduce global GHG emissions, (b) to bring about sustainable development in the developing countries lie on above two groups since its effect on February 16, 2005. Different polluters have different costs of pollution control. The least costly way of controlling pollution from various sources that reflects different costs of pollution control making the set of environmental regulations to achieve the emission target at the lowest cost makes the regulation cost-effective. Though efficiency is not attainable for many regulations, cost-effectiveness is attainable.  相似文献   
675.
The results of studies on the radial increment of larch and pine in central Yakutia are presented. The application of dendroclimatological methods to the study of tree-ring chronologies has made it possible to evaluate tree growth response to the dynamics of climatic factors over the past 120 years. The results of analysis of radial tree increment show that the onset of the growing season has shifted to earlier dates by the end of the 20th century.  相似文献   
676.
Nia Y  Garnier JM  Rigaud S  Hanna K  Ciffroy P 《Chemosphere》2011,85(9):1496-1504
The diffusive gradients technique in thin films (DGT) was used to investigate the kinetic resupply of Cd and Cu to pore water from the solid phase. For the sake of simplification, experiments were performed using formulated sediments that differed in the presence or absence of humic acids (HA) and/or of iron hydroxides (i.e., goethite and ferrihydrite). The effects of the time after the contamination of the solid phase (aging effect) on formulated sediments that were coated with goethite and HA and spiked with Cd were also evaluated. Kinetic DGT results were interpreted using the newly developed, multi-compartmental model DGT-PROFS.Due to Cu humate formation, the addition of HA slightly increased the Cu concentration in the pore water independent of the effect of the iron hydroxide coating on the formulated sediments and slightly decreased that of Cd. The impact of 8-190 d of aging resulted in a significant decrease in the Cd concentration of the pore water over an increasing incubation time.Modeling our results with DGT-PROFS led to the following conclusions concerning the impact of HA and iron hydroxides on Cd and Cu availability. First, in the presence of HA and absence of iron hydroxides, Cd is associated mainly with weak sites, while Cu is bound to strong sites. Similarly, in the presence of both iron hydroxides and HA, Cu appeared to be more heavily associated with the strong sites than did Cd. When the incubation time increased from 8 to 190 d, a proportion of Cd initially adsorbed onto weak sites transferred to the strong sites, suggesting that the adsorption of Cd on sediments is controlled partially by slow kinetic processes.  相似文献   
677.
It has been postulated that road deicing salts are sufficiently diluted by spring rains to ameliorate any physiological impacts to amphibians breeding in wetlands near roads. We tested this conjecture by exposing clutches of the spotted salamander (Ambystoma maculatum) to three chloride concentrations (1 mg/L, 145 mg/L, 945 mg/L) for nine days, then transferred clutches to control water for nine days, and measured change in mass at three-day intervals. We measured mass change because water uptake by clutches reduces risks to embryos associated with freezing, predation, and disease. Clutches in controls sequestered water asymptotically. Those in the moderate concentrations lost 18% mass initially and regained 14% after transfer to control water. Clutches in high concentration lost 33% mass and then lost an additional 8% after transfer. Our results suggest that spring rains do not ameliorate the effects of deicing salts in wetlands with extremely high chloride concentrations.  相似文献   
678.
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   
679.
Environmental change is likely to have a strong impact on biodiversity, and many species may shift their distribution in response. In this study, we aimed at projecting the availability of suitable habitat for an endangered amphibian species, the Fire-bellied toad Bombina bombina, in Brandenburg (north-eastern Germany). We modelled a potential habitat distribution map based on (1) a database with 10,581 presence records for Bombina from the years 1990 to 2009, (2) current estimates for ecogeographical variables (EGVs) and (3) the future projection of these EGVs according to the statistical regional model, respectively, the soil and water integrated model, applying the maximum entropy approach (Maxent). By comparing current and potential future distributions, we evaluated the projected change in distribution of suitable habitats and identified the environmental variables most associated with habitat suitability that turned out to be climatic variables related to the hydrological cycle. Under the applied scenario, our results indicate increasing habitat suitability in many areas and an extended range of suitable habitats. However, even if the environmental conditions in Brandenburg may change as predicted, it is questionable whether the Fire-bellied toad will truly benefit, as dispersal abilities of amphibian species are limited and strongly influenced by anthropogenic disturbances, that is, intensive agriculture, habitat destruction and fragmentation. Furthermore, agronomic pressure is likely to increase on productive areas with fertile soils and high water retention capacities, indeed those areas suitable for B. bombina. All these changes may affect temporary pond hydrology as well as the reproductive success and breeding phenology of toads.  相似文献   
680.
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