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691.
Thorsten Zellmann Alexandra S. Bäuerle Reiner Doluschitz Dietmar Jahnke Detlef Marell 《Environmental Sciences Europe》1999,11(1):49-54
The farming community is today faced with requests by various interest groups to implement environmental management systems (EMS). The series of items shows principle theoretical questions of the method and the advantages of EMS (part I and II), presents the practical outcome (part III) and give a recommendation for potential users of EMS in agricultural systems (part IV). The study conducted outlines the method of the implementing an EMS according to the Environmental Management and Audit System (EMAS) and ISO 14001. Further advantages and disadvantages for the agricultural industry are addressed. Even though terms such as site can not easily be defined or problems with open material cycles and structural particularity of agricultural farms there appears to be a benefit to implement. The transparency and documentation of the material flow as well as the economical benefits of an optimized organization count towards the EMS. Further EMS can be a means to strengthen the argumentative position for example with the public, authorities, banks or insurance. This concurs with minimizing company liabilities and obtaining governmental privileges (deregulation). 相似文献
692.
Pesticide risk assessment and management in a globally changing world—report from a European interdisciplinary workshop 总被引:1,自引:1,他引:0
Marc Babut Gertie H. Arts Anna Barra Caracciolo Nadia Carluer Nicolas Domange Nikolai Friberg Véronique Gouy Merete Grung Laurent Lagadic Fabrice Martin-Laurent Nicolas Mazzella Stéphane Pesce Benoit Real Stefan Reichenberger Erwin W. M. Roex Kees Romijn Manfred Röttele Marianne Stenrød Julien Tournebize Françoise Vernier Eric Vindimian 《Environmental science and pollution research international》2013,20(11):8298-8312
693.
The Baltic Sea runoff events during 1970–2000 were analysed with non-linear estimation in order to find potential stability
and time-varying (non-constancy) properties of time series parameters. In the Baltic Sea area, the wintertime rainfall is
expected to increase, especially in the northern parts of the watershed; furthermore, seasonality is expected to decrease,
i.e. the runoffs will become more evenly distributed over seasons, mainly by decreasing springtime peaks. We found a general
increase in runoffs over the time period studied that consisted of a level shift upwards during the early 1980s. The runoffs
considerably resulted from inputs in the months of April to June (which points to the significance of winter precipitation)
and are biased to northern parts of the catchment. Our results suggest that this is connected with snow and ice melting in
the northern areas of the watershed, especially in the subarctic catchment area of the Neva River (the area includes, for
example, three of the four biggest lakes in Europe, Lake Ladoga, Lake Onega and Lake Saimaa, which are annually covered by
ice). The yearly variation in runoff is significantly stabilised by large N–S extension of the watersheds of these lakes.
The results are generally in accordance with the presented climatic expectations; however, decreasing seasonality was not
obvious in the series yet. However, we found potential implications of system change towards decreased seasonality. By better
understanding of ongoing processes in the sea, the results can give us an opportunity to better evaluate the system control,
predicted areal consequences and ecosystem effects of the climate change. The analysis proved to be a sensitive tool for studying
climatic variation in a relatively small area and over a short time span. 相似文献
694.
Thorsten Junge Nicola Claßen Andreas Schäffer Burkhard Schmidt 《Journal of environmental science and health. Part. B》2013,48(9):858-868
The fate of 14C-labeled difloxacin (14C-DIF) was studied in time course experiments after application on soil (Ap horizon of silt loam) and amendment of authentic DIF containing pig manure (146 mL kg?1; 4.17 MBq kg?1; 0.85 mg kg?1) or water (124 mL kg?1; 0.42 MBq kg?1; 0.09 mg kg?1) for 56 and 120 days of incubation, respectively. Mineralization of 14C-DIF was below 0.2% in both experiments after 56 days or 120 days. In the course of the experiments, portions of extractable radioactivity (Accelerated Solvent Extraction (ASE); acetonitrile-water) decreased to 19–21% depending only little on manure amendment. Non-extractable residues of 14C-DIF increased to 70–74% after 56 days and 120 days, respectively, and therefore were the main route of 14C-DIF in soil. According to radioanalytical HPLC and LC-MS/MS, only the parent compound was found in all extracts over the whole time of the experiment. According to fractionation of the non-extractable residues (NER) into particle size fractions, 14C portions were associated to the water used for fractionation, the silt and clay fractions, whereas no radioactivity was detected in the sand fraction. The majority of 14C was found within the clay fractions. Fractionation of humic components showed that radioactivity derived from 14C-DIF was associated with humic acids, fulvic acids, humins and minerals and very little with soluble, non-humic HCl fraction. The highest portions of radioactivity were found in the fulvic acid fraction. Results obtained by size exclusion chromatography (SEC) of the purified fulvic acids were similar for every sample analyzed. One large portion of 14C co-eluted with fulvic acids of a molecular weight below 910 g mol?1. Both fractionation methods demonstrated that the parent compound DIF or initial metabolites were rapidly integrated into humic materials and, thus, were major components of NER. 相似文献
695.
Ulrika Eriksson Anna Kärrman Anna Rotander Bjørg Mikkelsen Maria Dam 《Environmental science and pollution research international》2013,20(11):7940-7948
Diet and drinking water are suggested to be major exposure pathways for perfluoroalkyl substances (PFASs). In this study, food items and water from Faroe Islands sampled in 2011/2012 were analyzed for 11 perfluoroalkyl carboxylic acids (PFCAs) and 4 perfluoroalkane sulfonic acids (PFSAs). The food samples included milk, yoghurt, crème fraiche, potatoes, fish, and fish feed, and the water samples included surface water and purified drinking water. In total, nine PFCAs and four PFSAs were detected. Generally, the levels of PFAS were in the lower picogram per gram range. Perfluorobutanoic acid was a major contributor to the total PFASs concentration in water samples and had a mean concentration of 750 pg/L. Perfluoroundecanoic acid (PFUnDA) was predominating in milk and wild fish with mean concentrations of 170 pg/g. Perfluorooctane sulfonic acid (PFOS) was most frequently detected in food items followed by PFUnDA, perfluorononanoic acid, and perfluorooctanoic acid (PFOA). Levels of PFUnDA and PFOA exceeded those of PFOS in milk and fish samples. Prevalence of long-chain PFCAs in Faroese food items and water is confirming earlier observations of their increase in Arctic biota. Predominance of short-chain and long-chain homologues indicates exposure from PFOS and PFOA replacement compounds. 相似文献
696.
697.
Eric Rahn Peter Läderach María Baca Charlotte Cressy Götz Schroth Daniella Malin Henk van Rikxoort Jefferson Shriver 《Mitigation and Adaptation Strategies for Global Change》2014,19(8):1119-1137
There are worldwide approximately 4.3 million coffee (Coffea arabica) producing smallholders generating a large share of tropical developing countries’ gross domestic product, notably in Central America. Their livelihoods and coffee production are facing major challenges due to projected climate change, requiring adaptation decisions that may range from changes in management practices to changes in crops or migration. Since management practices such as shade use and reforestation influence both climate vulnerability and carbon stocks in coffee, there may be synergies between climate change adaptation and mitigation that could make it advantageous to jointly pursue both objectives. In some cases, carbon accounting for mitigation actions might even be used to incentivize and subsidize adaptation actions. To assess potential synergies between climate change mitigation and adaptation in smallholder coffee production systems, we quantified (i) the potential of changes in coffee production and processing practices as well as other livelihood activities to reduce net greenhouse gas emissions, (ii) coffee farmers’ climate change vulnerability and need for adaptation, including the possibility of carbon markets subsidizing adaptation. We worked with smallholder organic coffee farmers in Northern Nicaragua, using workshops, interviews, farm visits and the Cool Farm Tool software to calculate greenhouse gas balances of coffee farms. From the 12 activities found to be relevant for adaptation, two showed strong and five showed modest synergies with mitigation. Afforestation of degraded areas with coffee agroforestry systems and boundary tree plantings resulted in the highest synergies between adaptation and mitigation. Financing possibilities for joint adaptation-mitigation activities could arise through carbon offsetting, carbon insetting, and carbon footprint reductions. Non-monetary benefits such as technical assistance and capacity building could be effective in promoting such synergies at low transaction costs. 相似文献
698.
INTRODUCTION: The use of hand-held cellular (mobile) phones while driving has stirred more debate, passion, and research than perhaps any other traffic safety issue in the past several years. There is ample research showing that the use of either hand-held or hands-free cellular phones can lead to unsafe driving patterns. Whether or not these performance deficits increase the risk of crash is difficult to establish, but recent studies are beginning to suggest that cellular phone use elevates crash risk. METHODS: The purpose of this study was to assess changes in the rate of hand-held cellular phone use by motor-vehicle drivers on a statewide level in Michigan. This study presents the results of 13 statewide surveys of cellular phone use over a 4-year period. Hand-held cellular phone use data were collected through direct observation while vehicles were stopped at intersections and freeway exit ramps. Data were weighted to be representative of all drivers traveling during daylight hours in Michigan. RESULTS: The study found that driver hand-held cellular phone use has more than doubled between 2001 and 2005, from 2.7% to 5.8%. This change represents an average increase of 0.78 percentage points per year. The 5.8% use rate observed in 2005 means that at any given daylight hour, around 36,550 drivers were conversing on cellular phones while driving on Michigan roadways. The trend line fitted to these data predicts that by the year 2010, driver hand-held cellular phone use will be around 8.6%, or 55,000 drivers at any given daylight hour. CONCLUSIONS: These results make it clear that cellular phone use while driving will continue to be an important traffic safety issue, and highlight the importance of continued attempts to generate new ways of alleviating this potential hazard. 相似文献
699.
Laapotti S Keskinen E Hatakka M Hernetkoski K Katila A Peräaho M Salo I 《Traffic injury prevention》2006,7(3):232-237
OBJECTIVE: The study evaluated the accident risk of certain driving circumstances and driving motives among novice drivers. METHODS: Self-reported exposure and accidents according to driving circumstances and driving motives were compared between young (n = 6,847) and middle-aged (n = 942) male and female novice drivers. For young drivers, self-reported accidents were further compared to fatal accidents (n = 645) in terms of the driving conditions in which they occurred. The survey was conducted in 2002 and the questions regarding the quantity and quality of driving exposure and accidents covered the first four years of the novice drivers' driving career after licensing. Data on fatal accidents related to the period of 1990 to 2000. RESULTS: Leisure-time driving, driving just for fun, and driving with passengers and during evenings and at night was more typical for young drivers than for middle-aged drivers. For middle-aged drivers, the most typical driving was driving to or from work. Driving on errands was more typical for females than males. Nighttime driving was overrepresented in young drivers' self-reported and fatal accidents, compared to the share of young drivers' driving at night. Slippery road conditions were over-represented in young male drivers' self-reported accidents, but not in their fatal accidents, whereas for young females slippery road conditions seemed to increase the propensity of fatal accidents. CONCLUSIONS: The study concluded that some driving conditions increase the risk of certain types of accidents among certain driver groups, but not among all drivers. For example, slippery road conditions were overrepresented in young male drivers' minor (self-reported) accidents, but not in their fatal accidents. For young female drivers slippery road conditions seem to increase the propensity of fatal accidents. Driving circumstances are different in minor (self-reported) and fatal accidents. When drawing conclusions regarding accident risk, it is important to determine the seriousness of the accidents which take place. 相似文献
700.
Variation partitioning of species data matrices: estimation and comparison of fractions 总被引:22,自引:0,他引:22
Establishing relationships between species distributions and environmental characteristics is a major goal in the search for forces driving species distributions. Canonical ordinations such as redundancy analysis and canonical correspondence analysis are invaluable tools for modeling communities through environmental predictors. They provide the means for conducting direct explanatory analysis in which the association among species can be studied according to their common and unique relationships with the environmental variables and other sets of predictors of interest, such as spatial variables. Variation partitioning can then be used to test and determine the likelihood of these sets of predictors in explaining patterns in community structure. Although variation partitioning in canonical analysis is routinely used in ecological analysis, no effort has been reported in the literature to consider appropriate estimators so that comparisons between fractions or, eventually, between different canonical models are meaningful. In this paper, we show that variation partitioning as currently applied in canonical analysis is biased. We present appropriate unbiased estimators. In addition, we outline a statistical test to compare fractions in canonical analysis. The question addressed by the test is whether two fractions of variation are significantly different from each other. Such assessment provides an important step toward attaining an understanding of the factors patterning community structure. The test is shown to have correct Type I. error rates and good power for both redundancy analysis and canonical correspondence analysis. 相似文献