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581.
This study was undertaken to evaluate the degradation and mobility of the herbicide tebuthiuron (N-[5-(1,1-dimethylethyl)-1,3,4-thiadiazol-2-yl]-N,N'-dimethylurea) in soil under field conditions, and its potential for leaching and groundwater contamination. A watershed, Espraiado, located over a recharge area in Brazil, was chosen for soil and water studies. At Espraiado, water samples were collected from seven wells at intervals of three months from March 2004 to June 2006 and analyzed for tebuthiuron. Other samples were taken from city wells located outside of the recharge area. To assess the potential movement to the aquifer, tebuthiuron was also applied to trial plots at the recommended label rate of 1.0 kg/ha a.i. in May of 2004, with and without sugarcane coverage, on sandy soil. Soil samples were collected during the years of 2004 and 2005, at depths intervals of 20 cm from soil surface down to 120 cm and analyzed for tebuthiuron at zero, 3, 30, 60, 90, 120, 150, 180, 240, and 300 days after application. There was no clear effect of sugarcane coverage on the tebuthiuron degradation in soils, but it moved faster into the soil where there was no cover. After 180 days there were no measurable residues in the soil, and tebuthiuron was not found below 40 cm depth in any time. Tebuthiuron had a half-life of 20 days under those conditions. No tebuthiuron residue was found in ground water samples at any sampling time.  相似文献   
582.
583.
The EMAS Regulation (Reg 761/01 EC) is EU scheme implemented by the European Commission since 1993 and it is for the implementation of an Environmental Management System (EMS) by any organization. The EMS was originally proposed by the European Commission and by the ISO as the frontrunner of a series of policy tools that enable companies to simultaneously pursue environmental objectives and competitive targets in a synergetic way.Based on the unique dataset of the EVER project, this paper investigates whether or not an EMS implemented within the EMAS Regulation has any effect on firm performance both from an environmental and a competitive point of view. Our econometric analysis shows the positive impact of a well-designed environmental management system on environmental performance and, as a consequence, on technical and organizational innovations. Effects on other competitive variables such as market performance, resource productivity and intangible assets are not strongly supported.  相似文献   
584.
A questionnaire on the perception of climate change and the impact of climate change was distributed among winegrowers in France, Germany, and Italy. These countries are located in three macro-climatic regions that experienced different patterns of climatic change in the twentieth century—Atlantic, transition to Continental and Mediterranean. The majority of winegrowers perceived changing climatic conditions in the last few decades. The characterization of these changes is consistent with results obtained by the analysis of long-term trends in climatic records. The winegrowers noted impacts on harvestable quantities (mainly in Italy), must quality, and risks of pests and diseases. The majority of respondents (66%) indicated an impact on wine quality, which was perceived as quality improvement in 55% of the cases. Perceived impacts on pests and diseases were reported in 56% of the responses. A strong majority of this group (80%) also reported increasing threats. Perceived climatic change and its noticeable impacts has led to growing interest in adaptation options, combined with a need for more information, among winegrowers. Thus, the transfer of technical knowledge from scientific research to practice is necessary for adaptation. Plans for adaptation by a change of wine varieties were reported with substantially different results among the regions. A majority of German growers said they would consider changing varieties to adapt to warming temperatures, while only a minority of the Italian and French growers said they would consider such changes. However, readiness to adopt adaptation measures is correlated with the degree of changes already planned, independent of climatic change.  相似文献   
585.
Environmental Fluid Mechanics - Linear stability analysis is used to investigate the behavior of small perturbations of a uniform flow in a straight channel with an erodible bed composed by a...  相似文献   
586.
Environmental Science and Pollution Research - The surface coating present on a marble Piety dating to the Renaissance period and stored at the Castello Sforzesco-Museum of Ancient Art (Milan,...  相似文献   
587.
Environmental Science and Pollution Research - Cyclodextrin nanosponges (CD-NS) are cross-linked cyclodextrin polymers characterized by a nanostructured three-dimensional network. CD-NSs in the...  相似文献   
588.
Journal of Material Cycles and Waste Management - In this work, the synthesis of biochar from several biomass wastes to act as matrix for urea was investigated. The objective was to select the most...  相似文献   
589.
Climate change severely impacts on the natural and socio-economic systems of the Pacific Islands. Samoa, a small insular state of the region, is characterized by widespread awareness of climate change reflected by its leading international role. This also makes Samoa a potentially exemplary reference for the Pacific Islands. Against this backdrop, the overall aim of this article is to investigate the notion of social vulnerability and measure its dimensions in Samoa through a specific index: the Samoa Social Vulnerability Index (SSVI). The SSVI may yield better understanding of the characteristics and dynamics of social vulnerability, as well as information for fostering adaptation strategies in Samoa and in the Pacific Islands. In particular, the article first outlines the major vulnerabilities to climate change in Samoa and then analyses the composite notion of social vulnerability. On this basis, the article methodologically specifies, designs and constructs the SSVI. Afterwards, it uses such index for measuring the dimensions of social vulnerability in Samoa’s districts. Finally, some considerations are made concerning the policy relevance of the SSVI and its potential regional role.  相似文献   
590.
Environmental Science and Pollution Research - The installation of district heating (DH) systems constitutes an advantage from the energetic, climate, and air quality aspects. However, the...  相似文献   
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