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131.
During the past 30 years, safety and environmental topics have moved up on the list of society’s significant concerns. Administrations and regulatory bodies have to publish rules for the protection of the public, decide whether to authorize the use of a chemical product or the construction of a new plant, limit the environmental impact, regulate waste disposal, etc. All these rules i.e. the legislative, normative and procedural corpus of a country, a state, a city or a factory can be designated to a barrier function. These barriers are indispensable and play an important role in industrial safety management. In developed countries, growth during the past few years in the number of laws directed at regulating environmental and safety aspects in industry is well known to everyone. Now the definition, classification and performance of the legislative and normative barriers definitely allow the management of technological risks. So it is possible to permit the identification of the flux of hazard and to perform risk reduction in order to enhance the acceptability in a regional context. A systemic risk analysis methodology was applied to Colombian industrial sectors. The current legislation was analyzed with three scenarios. A global panorama of the different existing instruments allowing future management opportunities was suggested. The obtained analysis results propose a point of view, which could be useful for a local government or a whole national system to evaluate or improve the risk legislative and normative barriers. This modeling can be applied to other countries and to other industrial sectors.  相似文献   
132.
Field investigations were conducted to measure subsoil trace element content and factors influencing content in an intensive periurban market garden in Chenggong County, Yunnan Province, South-West China. The area was divided into three di erent geomorphological units: specifically, mountain (M), transition (T) and lacustrine (L). Mean trace element content in subsoil were determined for Pb (58.2 mg/kg), Cd (0.89 mg/kg), Cu (129.2 mg/kg), and Zn (97.0 mg/kg). Strong significant relationships between trace element content in topsoil and subsoil were observed. Both Pb and Zn were accumulated in topsoil (RTS (ratio of mean trace element in topsoil to subsoil) of Pb and Zn >1.0) and Cd and Cu in subsoil (RTS of Cd and Cu 61.0). Subsoil trace element content was related to relief, stoniness, soil color, clay content, and cation exchange capacity. Except for 7.5 YR (yellow-red) color, trace element content increased with color intensity from brown to reddish brown. Significant positive relationships were observed between Fe content and that of Pb and Cu. Trace element content in mountain unit subsoil was higher than in transition and lacustrine units (M > T > L), except for Cu (T > M > L). Mean trace element content in calcareous subsoil was higher than in sandstone and shale. Mean trace element content in clay texture subsoil was higher than in sandy and sandy loam subsoil, and higher Cu and Zn content in subsoil with few mottles. It is possible to model Pb, Cd, Cu, and Zn distribution in subsoil physico-chemical characteristics to help improve agricultural practice.  相似文献   
133.
INTRODUCTION: Companies that use forklifts to load and unload trucks at loading docks are well aware of the main danger associated with this type of activity (i.e., the possibility of the forklift falling or tipping over when the truck suddenly moves away from the dock). Even if various truck restraint measures can be implemented to reduce the possibility of this type of accident, a number of hazardous incidents that result in a forklift tipping over from a loading dock still do occur regularly in day-to-day activities. This situation has brought experts to examine and evaluate the effectiveness of different measures and systems depending on the context in which they are used. METHODS: The present study touched upon both the technical and the organizational aspects of the restraint measures that could have an impact on safety. Certain elements were examined very closely, especially the failure of mechanical devices and their relation to the environment in which they are used, as well as the systemic interaction between people and the various restraint measures in use in a given context. CONCLUSION: This article presents a safety evaluation tool regarding restraint measures or systems for trucks docked at loading platforms - a tool that, of course, would take into consideration both the specific contextual aspects related to the docking bay itself, and to the plant. IMPACT ON INDUSTRY: This tool is designed to help companies choose the optimal safety measures to implement, while remaining realistic in terms of the technical and economic aspects of any given situation.  相似文献   
134.
135.
The contamination of the environment by explosives is a worldwide problem resulting in part from 2,4,6-trinitrotoluene (TNT) production. In situ phytoremediation is an appropriate, alternative, cost-effective technology to detoxify extended contamination of surface soil. The ability of rice (Oriza sativa) to both tolerate and assimilate 14C-labeled TNT was investigated over a 40-day exposure period. The germination rate decreased at 500 mg/kg TNT whereas root and shoot length increased significantly at high TNT concentrations, from 150 to 500 mg/kg. Rice took up TNT residues from soil and accumulated most in roots. Less than 25% of radioactivity taken up was translocated to aerial parts. Above 200 mg/kg TNT, the concentration of TNT residues in roots reached a maximum of approximately 0.7 mg/g. No TNT was found in plant extracts, good evidence for rapid metabolism of TNT. More than 60% of 14C activity was found as unextractable residues in roots. It was concluded that TNT metabolized and subsequently sequestered by roots could not be translocated to aerial parts.  相似文献   
136.
Longitudinal sampling of four cohorts of Neopomacentrus filamentosus, a common tropical damselfish from Dampier Archipelago, Western Australia, revealed the evolution of size structure after settlement. Light traps collected premetamorphic individuals from the water column ("settlers") to establish a baseline for each cohort. Subsequently, divers collected benthic juveniles ("recruits") at 1-3-month intervals to determine the relative impacts of post-settlement mortality during the first three months. Growth trajectories for individual fish were back-calculated from otolith records and compared with nonlinear mixed-effects models. Size-selective mortality was detected in all cohorts with the loss of smaller, slower growing individuals. Three months after settlement, recruits showed significantly faster growth as juveniles, faster growth as larvae, and larger sizes as hatchlings. The timing and intensity of post-settlement selection differed among cohorts and was correlated with density at settlement. The cohort with the greatest initial abundance experienced the strongest selective mortality, with most of this mortality occurring between one and two months after settlement when juveniles began foraging at higher positions in the water column. Significant genetic structure was found between settlers and three-month-old recruits in this cohort as a result of natural selection that changed the frequency of mtDNA haplotypes measured at the control region. The extent of this genetic difference was enlarged or reduced by artificially manipulating the intensity of size-based selection, thus establishing a link between phenotype and haplotype. Sequence variation in the control region of the mitochondrial genome has been linked to mitochondrial efficiency and weight gain in other studies, which provides a plausible explanation for the patterns observed here.  相似文献   
137.
The European legislation on ambient air quality introduces the concepts of spatial representativeness of a monitoring station and spatial extent of an exceedance zone. Spatial representativeness is an essential macro-scale siting criterion which should be evaluated before the setting-up and during the life of a monitoring point. As for the exceedance area, it has to be defined each time an environmental objective is exceeded in an assessment zone. No specific approach is prescribed to delimit such areas. A probabilistic methodology is presented, based on a preliminary kriging estimation of atmospheric concentrations at each point of the domain. It is applied to NO2 pollution on the urban scale. In the proposed approach, a point belongs to the area of representativeness of a station if its concentration differs from the station measurement by less than a given threshold. To take the estimation uncertainty into account, the standard deviation of the kriging error is used in a probabilistic framework. The choice of the criteria used to deal with overlapping areas is first tested on NO2 annual mean concentration maps of France, built by combining surface monitoring observations and outputs from the CHIMERE chemistry transport model. At the local scale, data from passive sampling surveys and high -resolution auxiliary variables are used to provide a more precise estimation of the background pollution in different French cities. The traffic-related pollution can also be accounted for in the map by additional predictors such as distance to the road, and traffic-related NOx emissions. Similarly, the proposed approach is implemented to identify the points, at a given statistical risk, where the NO2 concentration is above the annual limit value.  相似文献   
138.
Biodiversity monitoring surveys are rarely optimised statistically before being initiated. Here, we optimised the monitoring of plants in a temperate forest. The total inventory cost, the number and size of quadrats were optimised to detect a 10% change in species richness over 5 years with α = β = 0.05, using data from ongoing long-term floristic monitoring programs. The procedure showed that the inventory cost would be ca 15% lower using 100-, 200-m2 quadrats instead of 300- or 400-m2 quadrats. Despite the cost associated with the optimisation (e.g. gathering preliminary data) and the imprecise estimates (due to the typically small sample size of the pilot studies), optimisation would often be a better option than expert opinion when designing a monitoring survey.  相似文献   
139.
Wildlife tourism has become increasingly popular and is one of the fastest growing sectors of the tourism industry. A radio-acoustic positioning system was deployed to monitor the fine-scale movements of 21 white sharks (Carcharodon carcharias) and investigate the effects of shark cage-diving activities on their swimming behaviour and space use. This study contributes towards improving our understanding of the complex relationship between wildlife tourism and its effects on sharks, and assesses how tourism targeting sharks affects behaviour at a finer spatial scale than previously investigated. Our study demonstrated that shark cage-diving operators (SCDO) influenced the fine-scale three-dimensional spatial distribution and the rate of movement of white sharks at the Neptune Islands. White sharks stayed more than 30 m away from the SCDO on 21 % of the days detected, but spent a significant amount of time in close proximity to the SCDO on the remaining days. Individual variation was detected, with some sharks behaviourally responding to SCDO more than others. The degree of variation between individual sharks and the different levels of interaction (e.g. presence, proximity to SCDO, and consumption of tethered bait) highlights the complexity of the relationships between SCDO and the effects on sharks. To improve our understanding of these relationships, future monitoring of shark cage-diving operations requires proximity to SCDO to be recorded in addition to the presence within the area. Further work is needed to assess whether the observed behavioural changes would affect individual fitness and ultimately population viability, which are critical information to unambiguously assess the potential impacts of wildlife tourism targeting sharks.  相似文献   
140.
A method using Ion Chromatography hyphenated to an Inductively Coupled Plasma-Mass Spectrometer has been developed to accurately determine arsenite (As(III)), arsenate (As(V)), mono-methylarsonic acid (MMAA(V)), dimethylarsinic acid (DMAA(V)) and arsenobetaine (AsBet) in different water matrices. The developed method showed a high sensitivity with detection limits for each arsenic species close to 0.4pg injected. Arsenite and arsenate were the major species found in surface and well waters, but AsBet and DMAA(V) were found in some surface waters, which has never been reported before, while in some natural mineral waters located in volcanic region, the arsenic content exceeded the maximal admissible arsenic content by European legislation standards and the predominant form was As(V).  相似文献   
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