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381.
Changes in soil heavy metal extractability following the cessation of biosolids applications were studied in a long-term field experiment. Two anaerobically digested biosolids from wastewater treatment plants in Madrid (Sur and Viveros) were applied to cropland from 1983 to 1990. Soil samples were collected in the 1st, 5th and 9th year after the last biosolids application. Soil pH did not vary significantly after biosolids applications. Organic matter and total heavy metals (Zn, Pb, Cd, Ni, Cr and Cu) concentrations initially increased but then declined over time, mostly after the first 5 years following biosolids application. Metal extracted with DPTA increased in Sur treatments during the 1st year and diminished thereafter. However, in Viveros treatments, heavy metals extracted increased during the 1st year, declined in 1995, and showed a slight increase in 1999. These changes in heavy metal extractability were widely observed in the percentage of extractable metal recovery (EMR). The differences observed in the pattern of the two sources of biosolids applied could be due to the different rates of decomposition of their organic matter.  相似文献   
382.
383.
The microalgae genus Scenedesmus is commonly found in freshwater bodies, wastewater facilities and water polluted with heavy metals. Phenotypic plasticity in Scenedesmus has been documented in response to a wide variety of conditions; however, heavy metals have not been comprehensively documented as phenotypic plasticity inducers. In this study, we report the phenotypic plasticity of Scenedesmus incrassatulus (a non-spiny, four-cell coenobium forming species) in response to EC50 value of copper, cadmium and hexavalent chromium. S. incrassatulus was grown in batch cultures in the presence of each metal. Chlorophyll-a content, cell size, parameters derived from the schematic energy-flux model for photosystem II, and morphotype expressions were recorded. Divalent cation metals induced unicellular forms, and hexavalent chromium produced out-of-shape coenobia corresponding to various stages of autospore formation. The changes induced by divalent metals were interpreted as phenotypic plasticity, because they were always associated to population doublings and were reversible when toxicant pressure was removed (only for Cu). Copper was the best inductor of unicellular forms and also affected significantly all the photosynthetic parameters measured. The developed morphotypes could confer ecological advantages to S. incrassatulus in metal stressed environments.  相似文献   
384.
Objective: A zero tolerance alcohol restriction law was adopted in Brazil in 2008. In order to assess the effectiveness of this intervention, the present study compares specific mortality in 2 time series: 1980–2007 and 2008–2013.

Methods: Data on mortality and population were gathered from official Brazilian Ministry of Health information systems. Segmented regression analyses were carried out separately for 3 major Brazilian capitals: Belo Horizonte, Rio de Janeiro, and São Paulo.

Results: In 2 cities (Belo Horizonte and Rio de Janeiro) there were no significant changes in mortality rate trends in 2 periods, 1980 to 2007 and 2008 to 2013, where the observed rates did not differ significantly from predicted rates. In São Paulo, a decreasing trend until 2007 unexpectedly assumed higher levels after implementation of the law.

Conclusion: There is no evidence of reduced traffic-related mortality in the 3 major Brazilian capitals 5.5 years after the zero tolerance drinking and driving law was adopted.  相似文献   

385.
Agriculture, pesticides, food security and food safety   总被引:2,自引:0,他引:2  
Decades ago, agrochemicals were introduced aiming at enhancing crop yields and at protecting crops from pests. Due to adaptation and resistance developed by pests to chemicals, every year higher amounts and new chemical compounds are used to protect crops, causing undesired side effects and raising the costs of food production. Eventually, new techniques, including genetically modified organisms (GMOs) resistant to pests, could halt the massive spread of agrochemicals in agriculture fields. Biological chemical-free agriculture is gaining also more and more support but it is still not able to respond to the need for producing massive amounts of food. The use of agrochemicals, including pesticides, remains a common practice especially in tropical regions and South countries. Cheap compounds, such as DDT, HCH and lindane, that are environmentally persistent, are today banned from agriculture use in developed countries, but remain popular in developing countries. As a consequence, persistent residues of these chemicals contaminate food and disperse in the environment. Coordinated efforts are needed to increase the production of food but with a view to enhanced food quality and safety as well as to controlling residues of persistent pesticides in the environment.  相似文献   
386.
This paper describes an integrated approach to transform an industrial park into an eco-industrial park by combining three interconnected goals, namely, the consolidation of industrial symbiosis, the promotion of sustainable accessibility and the development of multi-functionalities. The result is an interdependent approach where industrial and territorial ecosystems are jointly planned, seeking a more sustainable level of development that considers industrial activity, the transportation of people and goods and the spatial articulation with the neighbouring environment and urban areas. The critical points and challenges for improving the territorial integration of the French industrial park of Salaise-Sablons are discussed, providing lessons for the future. Regardless of the specificities of the case study, this approach has the potential to be adopted in similar industrial parks.  相似文献   
387.
388.
Current studies indicate a need to integrate environmental management with manufacturing strategy, including topics like cross-functional integration, environmental impact, and waste reduction. Nevertheless, such studies are relatively rare, existing still a need for research in specific regional contexts. At the same time, the results found are not unanimous. Due to these gaps, the objective of this article is to analyze if environmental management can be considered a new competitive priority for manufacturing enterprises located in Brazil. A cross-sectional survey was conducted with Brazilian companies certified by ISO 14001. Sixty-five valid questionnaires were analyzed through Structural Equation Modelling (SEM). The first conclusion is that environmental management presents a preventive approach in the sample analyzed, focused on eco-efficiency, what potentially do not to create a competitive advantage. This preventive approach inhibits environmental management from being regarded as a new competitive manufacturing priority, in the full sense as defined by the literature. Another important result is that environmental management, although following a preventive focus, may influence positively the four manufacturing priorities: cost, quality, flexibility and delivery.  相似文献   
389.
Socio-economic, environmental, and governance impacts of illegal logging   总被引:2,自引:1,他引:1  
This article examines the main impacts of the illegal logging activities with emphasis on the most important timber production regions. Although the discussion is focused on the environmental, socio-economic and governance impacts, it must be stressed that the term forest governance is the umbrella where the economy, the environmental values, and welfare of forest-dependent communities are sheltered. Considering the effects/impacts of the illegal logging as a whole, we can summarize the following negative key points: (1) Degradation of the most valuable forest stands threatening biodiversity, including rare and endangered species. (2) Increase in soil erosion and landslides. Increase in CO2 release and climatic changes. (3) Human rights abuses and disrespect of the basic needs of local communities and their culture. (4) Corruption, crime, coercion, and money laundering. (5) Reduction of royalties, taxes, and other charges paid by logging companies to the producer States. (6) Depreciation of legal activities due to the unfair concurrence. Despite multiple efforts, the results in the combat of illegal logging are far from satisfactory. Increase the certification area in parallel with an accurate control, devolve the state land to the ancient local owners, increase the cooperation between civil society and forest authorities, and finally strongly improve forest governance, particularly anti-money laundering laws, are crucial aspects in the combat of illegal logging. Furthermore, governments and businesses must implement the triple bottom line concept in order to reach sustainability.  相似文献   
390.
The determination of 210Po and 210Pb was performed in marine organisms from the seashore to abyssal depths, encompassing a plethora of species from the microscopic plankton to the sperm whale. Concentrations of those radionuclides ranged from low values of about 5 × 10−1 Bq kg−1 (wet wt.) in jellyfish, to very high values of about of 3 × 104 Bq kg−1 (wet wt.) in the gut walls of sardines, with a common pattern of 210Po > 210Pb.These radionuclides are primarily absorbed from water and concentrated by phyto- and microzooplankton, and then are transferred to the next trophic level along marine food chains. Investigation in epipelagic, mesopelagic, bathypelagic and abyssobenthic organisms revealed that 210Po is transferred in the marine food webs with transfer factors ranging from 0.1 to 0.7, and numerically similar to those of the energy transfer in the marine food chains. As 210Po preferentially binds to amino acids and proteins, its transfer in food chains likely traces protein transfer and, thus, 210Po transfer factors are similar to ecotrophic coefficients. 210Pb is transferred less efficiently in marine food chains and this contributes to increased 210Po:210Pb activity ratios in some trophic levels.  相似文献   
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