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641.
We present a multi-model ensemble study for the Baltic Sea, and investigate the combined impact of changing climate, external nutrient supply, and fisheries on the marine ecosystem. The applied regional climate system model contains state-of-the-art component models for the atmosphere, sea ice, ocean, land surface, terrestrial and marine biogeochemistry, and marine food-web. Time-dependent scenario simulations for the period 1960–2100 are performed and uncertainties of future projections are estimated. In addition, reconstructions since 1850 are carried out to evaluate the models sensitivity to external stressors on long time scales. Information from scenario simulations are used to support decision-makers and stakeholders and to raise awareness of climate change, environmental problems, and possible abatement strategies among the general public using geovisualization. It is concluded that the study results are relevant for the Baltic Sea Action Plan of the Helsinki Commission.  相似文献   
642.
The use of mosses as biomonitors operates as an indicator of their concentration in the environment, becoming a methodology which provides a significant interpretation in terms of environmental quality. The different types of pollution are variables that can not be measured directly in the environment - latent variables. Therefore, we propose the use of factor analysis to estimate these variables in order to use them for spatial modelling. On the contrary, the main aim of the commonly used principal components analysis method is to explain the variability of observed variables and it does not permit to explicitly identify the different types of environmental contamination. We propose to model the concentration of each heavy metal as a linear combination of its main sources of pollution, similar to the case of multiple regression where these latent variables are identified as covariates, though these not being observed. Moreover, through the use of geostatistical methodologies, we suggest to obtain maps of predicted values for the different sources of pollution. With this, we summarize the information acquired from the concentration measurements of the various heavy metals, and make possible to easily determine the locations that suffer from a particular source of pollution.  相似文献   
643.
644.
The soy expansion model in Argentina generates structural changes in traditional lifestyles, which can be associated with different biophysical and socioeconomic impacts. To explore this issue, we apply an innovative method for integrated assessment—the multi-scale integrated analysis of societal and ecosystem metabolism framework—to characterize two communities in the Chaco Region, Province of Formosa, North of Argentina. These communities have recently experienced the expansion of soy production, altering their economic activity, energy consumption patterns, land use and human time allocation. The integrated characterization presented in the paper illustrates the differences (biophysical, socioeconomic and historical) between the two communities that can be associated with different responses. The analysis of the factors behind these differences has important policy implications for the sustainable development of local communities in the area.  相似文献   
645.
In this study, we compare the perception of climate change in two different tourist settings of northeastern Spain: the Catalan Pyrenees and the Catalan Mediterranean coast and the Balearic Islands. We carried out a survey of 906 cases (506 in the coastal areas of Catalonia and the Balearic Islands and 400 in the Catalan Pyrenees) asking residents on those areas to assess the possible effects of climate change on tourist-related activities. While the existence of climate change and of its estimated impacts is widely accepted, we observe statistically significant differences in most of the questions between residents in the coastal areas and residents in the Pyrenees. In general terms, respondents from the Pyrenees display a much higher concern regarding the economic impacts of climate change on tourism. On the other hand, the results also show that some demographic groups, such as women, members of large households, or unemployed, tend to present higher levels of concern. This study may give new hints on which tourist modalities and which groups are more concerned for the impacts of climate change in Mediterranean tourist environments and could translate into more targeted adaptive and mitigation practices.  相似文献   
646.
Land use and cover changes trigger multi-factorial responses with tangible and intangible effects. Driving forces governing changes are scale-, place- and time-dependent; because of their complexity, a multi-scalar analysis is required to determine conjoint causation. Studies using multi-scalar approach in semiarid scrubland ecosystems are scanty. This paper investigates land use changes on the largest semiarid scrubland ecosystem of Mexico, the Baja California Peninsula, using a multi-scalar analysis approach. It further provides insight into the likely underlying causes for land use trends. Multi-temporal databases were compiled for 1978, 1990, 2000 and 2003 from various sources; population was projected for the same years. Land cover processes were validated through intensive fieldwork. Map overlapping with the aid of geographic information systems allowed computation of land cover transformation rates. New algorithms were developed to better understand land cover trends. Multi-variate analysis was also performed to provide a synthetic statistical overview. Results showed that land cover change occurred at different times, at variable scales, due to distinct drivers. As a consequence, the current regional scenario has been shaped by distinguishable socio-economic changes. The semiarid scrubland ecosystems in the Baja California Peninsula experienced contrasting trends detectable only at site and local scales. Regionally, the replacement of original vegetation (scrubland) for other land cover category is following trends similar to those in the rest of Mexico and most semiarid ecosystems worldwide. These findings support the hypothesis that land use and cover changes must be analyzed at different times and scales to deeply understand underlying forces.  相似文献   
647.
Superficial sediments collected from seven estuarine systems located along the Portuguese coast were analyzed for 7 polychlorinated dibenzo-p-dioxins (PCDDs), 10 polychlorinated dibenzofurans (PCDFs), and 12 dioxin-like polychlorinated biphenyls (dl-PCBs). Total PCDD/F concentration ranged from 4.6 to 464 pg g?1 dry weight (dw), while that of dl-PCBs varied from 26.6 to 8,693 pg g?1 dw. In general, the highest PCDD/F and dl-PCB concentrations were associated with densely populated and industrially impacted areas. Additionally, PCDD/F revealed a predominance of octachlorodibenzodioxin (OCDD) to total PCDD/Fs, while PCB 118 was the major contributor to total dl-PCBs. This study provided a global perspective of the contamination status of Portuguese estuaries by dioxin-like compounds and allowed a comparison between the investigated systems and other systems worldwide. PCDD/F and dl-PCB levels found in the collected sediments were lower than those of highly impacted areas from different parts of the globe. Nevertheless, comparison with guidelines and quality standards from other countries indicated that some Portuguese estuarine areas with a high industrialization level present PCDD/F and dl-PCB concentrations in superficial sediment that may constitute a risk to aquatic organisms.  相似文献   
648.
This study reports a combined method using solid phase extraction (SPE), followed by solid phase microextraction (SPME) to concentrate different pesticides, including chlorinated, organophosphorus, triazines, pyretroids and chloroacetamides, present at trace levels in water samples. Identification and quantification was carried out by gas chromatography coupled to Mass Spectrometry (GC–MS). The optimized methodology showed LOQs at ng L?1 levels (ranging 0.2–3.5 ng L?1) in addition to acceptable precision and robustness (recoveries ranged 63–104%, RSD from 4% to 23%), presenting a novel method to reach trace levels, similar to that obtainable using EC detector, with structural confirmation by MS during the analysis of a wide range of environmental pollutants.This method was applied to the study of temporal and spatial distribution of pesticides in the Suquía River basin (Córdoba-Argentina). As expected, highest levels of agrochemicals were observed in areas with intensive agricultural practices, being atrazine (max. = 433.9 ng L?1), alpha-cypermetrine (max. = 121.7 ng L?1) and endosulfan sulfate (max. = 106.7 ng L?1) predominant. In urban areas, the prevalent pesticide was alpha-cypermethrine. These results draw attention to the need of pesticide monitoring programs in rivers, considering both urban and rural sections.  相似文献   
649.
Principal component analysis (PCA) coupled with a multilinear regression analysis (MLRA) was applied to PM(10) speciation data series (2002-2005) from four sampling sites in a highly industrialised area (ceramic production) in the process of implementing emission abatement technology. Five common factors with similar chemical profiles were identified at all the sites: mineral, regional background (influenced by the industrial estate located on the coast: an oil refinery and a power plant), sea spray, industrial 1 (manufacture and use of glaze components, including frit fusion) and road traffic. The contribution of the regional background differs slightly from site to site. The mineral factor, attributed to the sum of several sources (mainly the ceramic industry, but also with minor contributions from soil resuspension and African dust outbreaks) contributes between 9 and 11 microg m(-3) at all the sites. Source industrial 1 entails an increase in PM(10) levels between 4 and 5 microg m(-3) at the urban sites and 2 microg m(-3) at the suburban background site. However, after 2004, this source contributed less than 2 microg m(-3) at most sites, whereas the remaining sources did not show an upward or downward trend along the study period. This gradual decrease in the contribution of source industrial 1 coincides with the implementation of PM abatement technology in the frit fusion kilns of the area. This relationship enables us to assess the efficiency of the implementation of environmental technologies in terms of their impact on air quality.  相似文献   
650.
Urban wastewater treatment plant efficiency, as well as biosolid quality, depends on urban wastewater quality, which can be affected by non domestic discharges (industrial, commercial etc.). The characterization of wastewater quality and non domestic discharge is complex, expensive and time consuming. However, these discharges must be controlled and reduced if possible. The development of a simple and fast methodology, namely based on alternative methods such as UV spectrophotometry, has been carried out and applied to different areas of a medium sized town of Southern Québec (Canada). Several autosamplers and on line/on site measurements have been used in critical control points of the network areas, for a dry weather campaign in four areas (industrial, commercial, hospital and university). The flow rate study, completed by the exploitation of conductivity measurements and the qualitative examination of UV spectra allows the discrimination of non domestic loads and their variability study from one point to another. The identification of critical discharges and organic shock loads has been possible with low investment, and mitigation actions have been proposed.  相似文献   
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