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121.
The environmental, socioeconomic and cultural significance of glaciers has motivated several countries to regulate activities on glaciers and glacierized surroundings. However, laws written to specifically protect mountain glaciers have only recently been considered within national political agendas. Glacier Protection Laws (GPLs) originate in countries where mining has damaged glaciers and have been adopted with the aim of protecting the cryosphere from harmful activities. Here, we analyze GPLs in Argentina (approved) and Chile (under discussion) to identify potential environmental conflicts arising from law restrictions and omissions. We conclude that GPLs overlook the dynamics of glaciers and could prevent or delay actions needed to mitigate glacial hazards (e.g. artificial drainage of glacial lakes) thus placing populations at risk. Furthermore, GPL restrictions could hinder strategies (e.g. use of glacial lakes as reservoirs) to mitigate adverse impacts of climate change. Arguably, more flexible GPLs are needed to protect us from the changing cryosphere.  相似文献   
122.
Regional Environmental Change - Mediterranean forests are found in the Mediterranean basin, California, the South African Cape Province, South and southwestern Australia and parts of Central Chile....  相似文献   
123.
One of the main sources of reactive nitrogen pollution is animal manure. The disposal of digestate (material remaining after the anaerobic digestion of a biodegradable feedstock) in agricultural soils could solve both the problems of soil fertilization and waste removal, but the fate of digestate in the environment must be assessed carefully before its massive utilization. To investigate whether digestate could be safely employed as a soil fertilizer, an agricultural field located in Monastier di Treviso (Northern Italy) and characterized by the presence of low hydraulic conductivity clay soils, was selected to be amended with bovine digestate. The experimental site was intensively monitored by a three-dimensional array of probes recording soil water content, temperature, and electrical conductivity, to solve the water and bulk mass fluxes in the unsaturated zone. High-resolution soil coring allowed the characterization of soil water composition over two hydrological years. Chloride, found in high concentrations in the digestate, was used as environmental tracer to track the fate of the percolating water. The study concluded that digestate could be confidently employed in short rotation buffer areas at an average rate of 195 ± 26 kg-N/ha/year in low hydraulic conductivity soils not affected by diffuse fracturing during dry periods.  相似文献   
124.
We describe an action-research project whose objective was to help stakeholders at different organisational levels achieve sustainable land management by developing mediation models and tools. We chose to test a specific approach called companion modelling in the framework of a multidisciplinary research partnership and a formal local partnership (a ‘users committee’) involving an array of stakeholders at different organisational levels. The study area covers 10,000 km2 of agro-pastoral land around Lake Guiers in northern Senegal. We conducted studies to update the knowledge base of the area and organised six field workshops that clearly revealed three important tool functions to support decision-making on land use at different scales, i.e. understanding maps, monitoring and evaluating land tenure, and foreseeing changes in land use. We found that a toolbox approach was the best way to implement the three functions and overcome the constraints faced by the research team and those linked to the timing of the project. Therefore, we produced five simple complementary tools aimed at various users: a farm-level optimisation model (for researchers and technical services), a database for land allocations and a discussion tool to assess the impact of land allocation decisions (for the rural council), a paper atlas (for local players) and a regional land use change simulation model (for regional and national planners). Participants were able to work with paper maps, to interpret computer-generated simulations of land use change and understand the strengths and limitations of each. Self-assessment of the research process emphasised the importance of the context and the critical role played by social capital at both the research and the field level, which, in turn, emphasised the need for major improvements in the design and implementation of a quality process for participatory modelling. It turns out that action-research may be an effective way to undertake sustainability science.  相似文献   
125.
Awareness of groundwater protection has increased substantially in recent decades. In the Province of Quebec, Canada, the Groundwater Catchment Regulation (GWCR) was promulgated in 2002 to protect water quality in public wells. The goal of the present study was to document groundwater protection in the context of emerging regulations and identify factors explaining the propensity of municipalities applying protection strategies. Two types of information were used in this study: data from a questionnaire-based survey conducted among 665 municipalities in the Province of Quebec and complementary information gathered from various sources. Data from the survey revealed that fewer than half of the municipalities have been able to comply with the GWCR, mainly because of financial limitations. Also, close to half of the municipalities have either identified or are expecting land use conflicts to arise between protection areas required by the GWCR and other land usage, with agriculture being the main conflicting activity. Multivariate logistic regression models served to identify factors explaining the likelihood of municipalities to take groundwater protection measures. Those factors were municipality revenue, history of water contamination in distribution systems, land use near wellheads, location of municipalities within a provincial priority watershed and the importance of groundwater use in a region. Results of the study may prove helpful for government authorities in better understanding the groundwater protection issue and in implementing strategies that improve the ability of municipalities to protect groundwater.  相似文献   
126.
Dioxin analysis in food and feed can be characterized as an analytical application where very high accuracy is required at very low levels of contamination. Gas chromatography (GC) in combination with 13C-label isotope dilution (ID) high resolution mass spectrometry (HRMS) is the reference congener-specific technique characterized by pronounced selectivity, precision and trueness at parts-per-trillion (ppt) and sub-parts-per-trillion (sub-ppt) levels. The quality of the analytical data produced routinely by a laboratory should be adequate for its intended purpose, i.e., one will seek a compromise between the cost and time needed and the consequences of incorrect decisions due to erroneous results. The requirements for reproducibility are usually dependent on the analyte concentrations and have been expressed in various empirical functions. While Horwitz or modified functions are widely useful for many purposes, it would be difficult to expect these functions to cover every analytical problem. This study reports on precision characteristics achieved by the GC-ID-HRMS reference method for polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs) and dioxin-like polychlorinated biphenyls (DL-PCBs) in food and feed in two interlaboratory method-performance studies among expert laboratories with long-standing experience in this field. Striking linear functions in log scale between reproducibility standard deviation and congener's level over a concentration range of 10(-8)-10(-14)g per g fresh weight are observed. The data fit very well to a Horwitz-type function of the form sR=0.153c0.904, where sR and c are dimensionless mass ratios expressed in pg g(-1) on fresh weight, regardless of the nature of the toxic congeners, food and feed matrices, or sample preparation methods. We demonstrate that the proposed function is suitable for use as a fitness-for-purpose criterion for proficiency assessment in interlaboratory comparisons on dioxins and related compounds in food.  相似文献   
127.
A French monitoring study was initiated to evaluate the exposure of fetus and newborn to brominated flame retardants (BFR). A previously developed multi-residue analytical method was used for measuring the main classes of BFR (tetrabromobisphenol-A, and tri- to decabomodiphenyl ethers) in various human biological matrices. Analyzed samples (maternal and cord serum, adipose tissue and breast milk) were collected from 93 volunteer women during caesarean deliveries. TBBPA was detected in 44% of the analyzed breast milk samples, at levels varying from 0.06 to 37.34 ng g(-1) lipid weight, but was not detected in adipose tissue. This compound was also detected in 30% of the analyzed serum samples, with similar average values in maternal and cord serum (154 pg g(-1) fresh weight versus 199 pg g(-1) fresh weight, respectively). The interpretation of the collected data permitted the demonstration of (1) a significant exposure to TBBPA both for mothers and fetuses and (2) a possible risk of overexposure of newborns through breastfeeding.  相似文献   
128.
129.
Because mycorrhizal fungi are intimately associated with plant roots, their importance in radionuclide (RN) recycling and subsequent dispersion into the biosphere has received an increasing interest. Recently, the capacity of arbuscular mycorrhizal fungi to take up and translocate radiocaesium to their host was demonstrated. However, the relative contribution of these processes in comparison to the ones of roots remains unknown. Here, the respective contributions of the hyphae of a Glomus species and the transformed carrot (Daucus carota L.) roots on radiocaesium uptake and translocation were compared and quantified. We observed that radiocaesium uptake by hyphae was significantly lower as compared to that of the roots, while the opposite was noted for radiocaesium translocation/uptake ratio. We also observed that the intraradical fungal structures might induce a local accumulation of radiocaesium and concurrently reduce its translocation within mycorrhizal roots. We believe that intraradical fungal structures might induce the down-regulation of radiocaesium channels involved in the transport processes of radiocaesium towards the xylem.  相似文献   
130.
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