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81.
The purpose of this study is to offer an analysis of how two UN Conferences of Parties, COP15 in Copenhagen 2009 and COP21 in Paris 2015, were covered and debated in Swedish newspapers. Two national and two regional newspapers were selected for the study, and a qualitative frame analysis was conducted on 309 articles. A typology of frames applicable to science-related policy and climate change debates was used and its relevance for global climate summit context was discussed. Having territory in the Arctic region, indigenous populations affected by climate change measures, and political and public sensitivity to environmental issues, the climate debate has particular significance in the Swedish case. Findings indicate a trust in the role of national and supra-national governance to address climate change problems, but also that newspapers in Sweden maintained a focus on the global aspects of the two meetings, rather than framing them as surrogate battlefields for domestic politics.  相似文献   
82.
Several community gardens have been developed in Edinburgh over the past five years, which reflects renewed interest in “grow your own” projects, and the recognition of the associated environmental and social health benefits they provide. Community gardens have been included in a range of policy documents at national and local levels, acknowledging their contribution to sustainable food systems, health and well-being and environment and biodiversity. This research explores how public policy influences community garden practice and, reflexively, how organisations running community gardens in the third sector are represented in public policy frameworks. A mixed methodology of desk-based research of policy documents, associated reports and academic literature; and informal interviews with community gardens staff and organisers was utilised. It was found that while community gardens are represented in policy, at a national level the framing of community gardens and related food growing projects as “alternative” hinders their full potential. Community gardens fulfil a wide range of policy goals, particularly in the health, social capital and well-being sectors which can minimise their capacity to contribute to local food production in a substantial way. It is proposed that community gardens could be normalised by promoting gardens in visible locations in neighbourhoods and within local plans; and through reflexive strategic and community action utilising a reasoning backwards approach to planning and funding.  相似文献   
83.
84.
Genotoxic potential of two environmental compartments (water and sediment) from the Upper Silesia Coal Basin (USCB), Poland were evaluated and compared by employing root meristem cells of Allium cepa. The clear genotoxic effect of water and sediment sampled was shown, with an important contribution of severe types of cytogenetic abnormalities. The most biologically relevant pollutants were revealed through multivariate statistical analysis of relationships between biological effects registered and the environment contamination. Overall, results of simultaneous use of conventional monitoring methods and biological tests suggested that contemporary levels of persistent pollutants in post-mining areas of the USCB may enhance the risk both for human health and biological components of natural ecosystems.  相似文献   
85.
Increasing eutrophication and algal bloom events in the Yangtze River Three Gorges Reservoir, China, are widely discussed with regard to changed hydrodynamics and nutrient transport and distribution processes. Insights into water exchange and interaction processes between water masses related to large-scale water level fluctuations in the reservoir are crucial to understand water quality and eutrophication dynamics. Therefore, confluence zones of tributaries with the Yangtze River main stream are dedicated key interfaces. In this study, water quality data were recorded in situ and on-line in varying depths with the MINIBAT towed underwater multi-sensor system in the confluence zone of the Daning River and the Yangtze River close to Wushan City during 1 week in August 2011. Geostatistical evaluation of the water quality data was performed, and results were compared to phosphorus contents of selective water samples. The strongly rising water level throughout the measurement period caused Yangtze River water masses to flow upstream into the tributary and supply their higher nutrient and particulate loads into the tributary water body. Rapid algal growth and sedimentation occurred immediately when hydrodynamic conditions in the confluence zone became more serene again. Consequently, water from the Yangtze River main stream can play a key role in providing nutrients to the algal bloom stricken water bodies of its tributaries.  相似文献   
86.
System stability and performance of high-solids anaerobic co-digestion of dewatered sludge (DS) and food waste (FW) in comparison with mono digestions were investigated. System stability was improved in co-digestion systems with co-substrate acting as a diluting agent to toxic chemicals like ammonia or Na+. For high-solids digestion of DS, the addition of FW not only improved system stability but also greatly enhanced volumetric biogas production. For high-solids digestion of FW, the addition of DS could reduce Na+ concentration and help maintain satisfactory stability during the conversion of FW into biogas. System performances of co-digestion systems were mainly determined by the mixing ratios of DS and FW. Biogas production and volatile solids (VSs) reduction in digestion of the co-mixture of DS and FW increased linearly with higher ratios of FW. A kinetic model, which aimed to forecast the performance of co-digestion and to assist reactor design, was developed from long-term semi-continuous experiments. Maximum VS reduction for DS and FW was estimated to be 44.3% and 90.3%, respectively, and first order constant k was found to be 0.17 d?1 and 0.50 d?1, respectively. Experimental data of co-digestion were in good conformity to the predictions of the model.  相似文献   
87.
Thirty four phytoterpenoids were evaluated for their nematicidal effect using the model nematode Caenorhabditis elegans. Nematicidal activities of the tested compounds at concentrations of 50 μg/mL showed wide variation in their effects ranging from no effect, weak, moderate and strong effects. Terpenoids exerting 50% or higher mortality at 50 μg/mL were further tested at five different concentrations to calculate the concentration that will kill 50% of the nematode population (LC50). Among the most effective terpenoids were carvacrol, thymol, nerolidol, α-terpinene, geraniol, citronellol, farnesol, limonene, pseudoionone and eugenol in a descending order. These compounds exhibited a dose-dependent effect. The results suggest that the selected monoterpenoids and essential oils with a high concentration of these compounds mayprovide potential natural nematicides and merit further study as botanical nematicides for the control of both plant and animal parasitic nematodes. In general, oxygenated terpenoids and phenolic terpenoids exhibited higher nematicidal activity than hydrocarbons terpenoids.  相似文献   
88.
Previous research has shown that plant diversity influences N and P cycles. However, the effect of plant diversity on complete ecosystem N and P budgets has not yet been assessed. For 20 plots of artificially established grassland mixtures differing in plant diversity, we determined N and P inputs by bulk and dry deposition and N and P losses by mowing (and subsequent removal of the biomass) and leaching from April 2003 to March 2004. Total deposition of N and P was 2.3 +/- 0.1 and 0.2 +/- 0.01 g m(-2) yr(-1), respectively. Mowing was the main N and P loss. The net N and P budgets were negative (-6.3 +/- 1.1 g N and -1.9 +/- 0.2 g P m(-2) yr(-1)). For N, this included a conservative estimate of atmospheric N(2) fixation. Nitrogen losses as N(2)O were expected to be small at our study site (<0.05 g m(-2) yr(-1)). Legumes increased the removal of N with the harvest and decreased leaching of NH(4)-N and dissolved organic nitrogen (DON) from the canopy. Reduced roughness of grass-containing mixtures decreased dry deposition of N and P. Total dissolved P and NO(3)-N leaching from the canopy increased in the presence of grasses attributable to the decreased N and P demand of grass-containing mixtures. Species richness did not have an effect on any of the studied fluxes. Our results demonstrate that the N and P fluxes in managed grassland are modified by the presence or absence of particular functional plant groups and are mainly driven by the management.  相似文献   
89.
Bivalves have a known ability to accumulate different contaminants from ambient water and can therefore serve as bioindicators. The paper analyses certain biochemical and physiological parameters of blue mussels in response to varying oil product concentrations. The heart rate (HR) of blue mussels from the sublittoral zone exposed to different levels of oil products was investigated in a long-term experiment using non-invasive monitoring. A sharp rise in HR was observed at oil concentrations of 8.0 and 38.0 mg/l. A decreasing in mussel HR under the effect of lower concentrations (0.4 and 1.9 mg/l) was significant on the fourth day. Strong fluctuations of the cardiac activity were noted under all concentrations. After 6 days of oil treatment, tissues of the mussels were sampled to determine the total lipid composition. Low concentrations of oil products produced no reliable changes in the lipid composition whereas high concentrations induced significant changes in the ratio of lipid components (cholesterol and phospholipids).  相似文献   
90.
Fluorinated compounds (FC) are high-global warming potential (GWP) greenhouse gases used and emitted during the manufacture of silicon semiconductor devices. Following the U.S. EPA's PFC Emissions Vintage Model (PEVM), uncontrolled FC emissions are modeled as proportional to total manufactured layer area (TMLA) of silicon. FC emissions of World Semiconductor Council (WSC) charter member countries (Europe, Japan, Korea, Taiwan and the United States), which voluntarily committed in 1999 to lower FC emissions by 2010 to 10% of baseline year emissions, are modeled for the period 1995–2020. For this same period, emissions from Chinese manufacturers under alternative emission reduction scenarios are modeled. If Chinese manufacturers were to adopt a baseline year of 2005 and a reduction target of 10% below baseline year emissions to be achieved by 2020, emissions would be 3.4 MMTCO2eq, comparable to the similarly projected controlled emissions of an average WSC charter member country (=16.3/5 MMTCO2eq) in 2020. The relative stringency of the alternative reduction scenarios considered for China vary between 50 and 95% reduction compared to business as usual (BAU). This is comparable to the stringency of the WSC charter members’ goals for which FC emission reduction technologies are currently available.  相似文献   
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