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791.
Ross N. Cuthbert Sven Bacher Tim M. Blackburn Elizabeta Briski Christophe Diagne Jaimie T. A. Dick Franz Essl Piero Genovesi Phillip J. Haubrock Guillaume Latombe Bernd Lenzner Yves Meinard Aníbal Pauchard Petr Pyšek Anthony Ricciardi David M. Richardson James C. Russell Daniel Simberloff Franck Courchamp 《Conservation biology》2020,34(6):1579-1582
Article impact statement: In an era of profound biodiversity crisis, invasion costs, invader impacts, and human agency should not be dismissed. 相似文献
792.
Biswas Bhabananda Labille Jérôme Prelot Benedicte 《Environmental science and pollution research international》2020,27(31):38381-38383
Environmental Science and Pollution Research - 相似文献
793.
The implementation of land-use planning (LUP) impacts on the environment and may degrade regional environmental quality due to the changes in land-use patterns. To minimize the environmental impact of non-LUP driven (NPD) land-use background changes (LUBC), we propose an NPD land-use background change (NPD-LUBC) methodology to improve the LUP environmental impact assessment (LUPEA) process. With the application of the state-impact-state (SIS) framework and spatial information technologies including remote sensing and geographic information system (GIS), the methodology was tested on the eastern Chinese city of Lianyungang. The results indicate that (1) our proposed methodology is capable of distinguishing the environmental impact in implementing a target LUP, i.e. a LUP scheme to be assessed, from those driven by NPD-LUBC; (2) the prediction of NPD Land-use pattern simulated through the discrimination of NPD forces provides the basic data to support the LUPEA using our proposed methodology; (3) SO2, PM10, and COD emitted into the atmosphere and water are the major pollutants considered in the LUPEA of the city; and (4) despite the positive impacts of the comprehensive land-use change under the direction of target LUP, the implementation of LUP would have negative impacts on the regional environment in the entire study area and in individual counties/districts respectively in 2020. Our proposed methodology provides a new and operable way for the areas with data to simulate NPD land-use pattern and predict the individual indicator values for the assessment. 相似文献
794.
Combustible dust explosions continue to present a significant threat toward operating personnel and pneumatic conveyance equipment in a wide variety of processing industries. Following ignition of suspended fuel within a primary enclosure volume, propagation of flame and pressure fronts toward upstream or downstream interconnected enclosures can result in devastating secondary explosions if not impeded through an appropriate isolation mechanism. In such occurrences, an accelerated flame front may result in flame jet ignition within the secondary vessel, greatly increasing the overall explosion severity. Unlike an isolated deflagration event with quantifiable reduced pressures (vent sizing according to NFPA 68 guidance), oscillation of pressure between primary and secondary process vessels leads to uncertain overpressure effects. Dependent on details of the application such as relative enclosure volumes, relief area, fuel type, suspended concentration, duct size, and duct length, the maximum system pressure in both interconnected vessels can be unpredictable. This study proposes the use of FLame ACceleration Simulator (FLACS) computational fluid dynamics (CFD) modeling to provide reliable consequence predictions for specific case scenarios of dust deflagrations involving interconnected equipment. Required minimum supplement to the originally calculated relief area (Av) was determined through iterative simulation, allowing for reduced explosion pressures (Pred) to be maintained below theoretical enclosure design strengths (Pes). 相似文献
795.
Radium isotopes are widely used in marine studies (eg. to trace water masses, to quantify mixing processes or to study submarine groundwater discharge). While 228Ra and 226Ra are usually measured using gamma spectrometry, short-lived Ra isotopes (224Ra and 223Ra) are usually measured using a Radium Delayed Coincidence Counter (RaDeCC). Here we show that the four radium isotopes can be analyzed using gamma spectrometry. We report 226Ra, 228Ra, 224Ra, 223Ra activities measured using low-background gamma spectrometry in standard samples, in water samples collected in the vicinity of our laboratory (La Palme and Vaccarès lagoons, France) but also in seawater samples collected in the plume of the Amazon river, off French Guyana (AMANDES project). The 223Ra and 224Ra activities determined in these samples using gamma spectrometry were compared to the activities determined using RaDeCC. Activities determined using the two techniques are in good agreement. Uncertainties associated with the 224Ra activities are similar for the two techniques. RaDeCC is more sensitive for the detection of low 223Ra activities. Gamma spectrometry thus constitutes an alternate method for the determination of short-lived Ra isotopes. 相似文献
796.
Luke D. Ziemba Jack E. Dibb Robert J. Griffin L. Gregory Huey Pieter Beckman 《Atmospheric environment (Oxford, England : 1994)》2010,44(13):1649-1657
Observations of particle size distributions suggest that particles grow significantly just above the snow surface at a remote, Arctic site. Measurements were made at Summit, Greenland (71.38°N and 31.98°W) at approximately 3200 m above sea level. No new particle formation was observed locally, but growth of ultrafine particles was identified by continuous evolution of the geometric mean diameter (GMD) during four events. The duration of the growth during events was between 24 and 115 h, and calculated event-average growth rates (GR) were 0.09, 0.30, 0.27, and 0.18 nm h?1 during each event, respectively. Four-hour GR up to 0.96 nm h?1 were observed. Events occurred during below- and above-average temperatures and were independent of wind direction. Correlation analysis of hourly-calculated GR suggested that particle growth was limited by the availability of photochemically produced precursor gases. Sulfuric acid played a very minor role in particle growth, which was likely dominated by condensation of organic compounds, the source of which was presumably the snow surface. The role of boundary layer dynamics is not definite, although some mixing at the surface is necessary for the observation of particle growth. Due to the potentially large geographic extent of events, observations described here may provide a link between long-range transport of mid-latitude pollutants and climate regulation in the remote Arctic. 相似文献
797.
David D. Cohen Jagoda Crawford Eduard Stelcer Vuong Thu Bac 《Atmospheric environment (Oxford, England : 1994)》2010,44(31):3761-3769
Fine particulate matter (PM2.5), source fingerprints and their contributions have been measured and reported previously at Hanoi, Vietnam, from 25 April 2001 to 31 December 2008. In this study back trajectories are used to identify long range transport into Hanoi for two of these sources, namely, windblown dust (Soil) from 12 major deserts in China and emissions from 33 coal fired power plants (Coal) in Vietnam and China. There were 28 days of extreme Soil events with concentrations greater than 6 μg m?3 and 25 days of extreme Coal with concentrations greater than 30 μg m?3 from a total of 748 sampling days during the study period. Through the use of back trajectories it was found that long range transport of soil from the Taklamakan and Gobi desert regions (more than 3000 km to the north west) accounted for 76% of the extreme events for Soil. The three local Vietnamese power stations contributed to 15% of the extreme Coal events, while four Chinese power stations between 300 km and 1700 km to the north-east of Hanoi contributed 50% of the total extreme Coal events measured at the Hanoi sampling site. 相似文献
798.
F.J. de Ruijter J.F.M. Huijsmans B. Rutgers 《Atmospheric environment (Oxford, England : 1994)》2010,44(28):3362-3368
Agricultural systems can lose substantial amounts of nitrogen (N). To protect the environment, the European Union (EU) has adopted several directives that set goals to limit N losses. National Emission Ceilings (NEC) are prescribed in the NEC directive for nitrogen oxides and ammonia. Crop residues may contribute to ammonia volatilization, but sufficient information on their contribution to the national ammonia volatilization is lacking. Experiments were carried out with the aim to assess the ammonia volatilization of crop residues left on the soil surface or incorporated into the soil under the conditions met in practice in the Netherlands during late autumn and winter.Ammonia emission from residues of broccoli, leek, sugar beet, cut grass, fodder radish (fresh and frozen) and yellow mustard (frozen) was studied during two winter seasons using volatilization chambers. Residues were either placed on top of soil or mixed with soil. Mixing residues with soil gave insignificant ammonia volatilization, whereas volatilization was 5–16 percent of the N content of residues when placed on top of soil.Ammonia volatilization started after at least 4 days. Total ammonia volatilization was related to C/N-ratio and N concentration of the plant material. After 37 days, cumulative ammonia volatilization was negligible from plant material with N concentration below 2 percent, and was 10 percent of the N content of plant material with 4 percent N. These observations can be explained by decomposition of plant material by micro-organisms. After an initial built up of the microbial population, NH4+ that is not needed for their own growth is released and can easily emit as NH3 at the soil surface.The results of the experiments were used to estimate the contribution of crop residues to ammonia volatilization in the Netherlands. Crop residues of arable crops and residues of pasture topping may contribute more than 3 million kg NH3–N to the national ammonia volatilization of the Netherlands, being more than 3 percent of the national emissions in 2005. This contribution should therefore be considered when focusing on the national ceilings for ammonia emissions. 相似文献
799.
Francis Stoessel 《Process Safety and Environmental Protection》2009,87(2):105-112
A systematic approach to the assessment of thermal risks linked with the performance of exothermal reactions at industrial scale was proposed a long time ago. The approach consisted of a runaway scenario starting from a cooling failure and a classification of these scenarios into criticality classes. In the mean time these tools became quite popular and many chemical companies use them. Recently, the international standard IEC 61511 required the use of protection systems with reliability depending on the risk level. Since the criticality classes were developed as a tool for the choice of risk reducing measures as a function of the criticality, it seems obvious that the criticality classes may be used in the context of the standard IEC 61511, which provides a relation between the risk level and the reliability of protection systems.Firstly, the runaway scenario and the criticality classes will be shortly described. Secondly, the assessment criteria for severity and probability of occurrence of a runaway scenario will be described together with the required data and their interpretation in terms of risk. Thirdly, the assessment procedure is exemplified for the different criticality classes. Finally, the design of protection measures against runaway and the required IPL and SIL are based on the risk assessment obtained from the criticality classes. This approach allows minimising the required data set for the safety assessment and for the definition of the protection system designed in order to avoid the development of the runaway. 相似文献
800.
C.P. Lin H.K. Chang Y.M. Chang S.W. Chen C.M. Shu 《Process Safety and Environmental Protection》2009,87(6):353-360
In the past two decades, there has been continuous investment and expansion of semiconductor, photoelectric panel, or solar cell plants in the high-tech industry. For example, establishing a semiconductor plant costs about US$ 3 billion. In addition, the output value of integrated circuits (IC) of Taiwan as a whole is estimated to be about US$ 5.215 billion, and globally of US$ 275.2 billion in 2008. A large amount and a variety of specialty gases or chemicals are applied during processes in high-tech facilities and these chemicals are characterized by inflammability, toxicity, and corrosiveness. Accidents may result once errors or leaks occur in any part of the supply chain, which consists of storage facilities, supply equipment, process machines, and tail gas elimination devices. Personnel casualties can result in serious situations. This study discusses the emergency response procedures and common response defects in semiconductor plants with a view to enhancing emergency response effects and capabilities, avoiding casualties, reducing property loss and shortening operation interruption. 相似文献