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451.
Making the concept of Reducing Emissions from Deforestation and Degradation (REDD+) ready to be a mechanism to combat tropical deforestation and associated greenhouse gas (GHG) emissions by compensating developing countries for income foregone in reducing their rates of deforestation, requires solutions for outstanding controversies. Existing opinions on REDD+ vary greatly. By using the Q-method as part of an action research approach, this paper investigates experts’ attitudes towards REDD+. Based on their responses to 41 statements, four attitudinal groups were identified, characterized as pragmatists, sceptics, conventionalists and optimists. Opinions between groups differed as to the level of application, credibility, eligibility, economic effectiveness, and public acceptability of REDD+ policy instruments. Three of the four groups were supportive of international REDD+ type policy interventions, but there was disagreement on the more concrete design issues of REDD+ projects, such as the allocation of responsibilities, the distribution of burdens and benefits, and whether or not co-benefits could be expected, or should be required. As the potential of REDD+ is shaped not only by international climate policy but also by national and regional policies and stakeholder perceptions, this paper suggests that participatory forms of decision-making may help to develop tailor-made solutions that are supported by the many different actors that are necessarily involved in REDD+ projects.  相似文献   
452.
In this study, the prevalence of different enteric viruses in commercial mussels was evaluated at the retail level in three European countries (Finland, Greece and Spain). A total of 153 mussel samples from different origins were analysed for human norovirus (NoV) genogroups I and II, hepatitis A virus (HAV) and hepatitis E virus (HEV). Human adenovirus (HAdV) was also tested as an indicator of human faecal contamination. A full set of controls (such as sample process control, internal amplification controls, and positive and negative controls) were implemented during the process. The use of a sample process control allowed us to calculate the efficiencies of extraction, which ranged from 79 to 0.5?%, with an average value of 10?%. Samples were positive in 41?% of cases, with HAdV being the most prevalent virus detected (36?%), but no significant correlation was found between the presence of HAdV and human NoV, HAV and HEV. The prevalences of human norovirus genogroup II, HEV and human NoV genogroup I were 16, 3 and 0.7?%, respectively, and HAV was not detected. The estimated number of PCR detectable units varied between 24 and 1.4?×?103?g?1 of digestive tract. Interestingly, there appeared to be a significant association between the type of mussel species (M. galloprovincialis) and the positive result of samples, although a complete overlap between country and species examined required this finding to be confirmed including samples of both species from all possible countries of origin.  相似文献   
453.
454.
Environmental Science and Pollution Research - Microplastic pollution is one of the greatest environmental concerns for contemporary times and the future. In the last years, the number of...  相似文献   
455.
456.
Multitracers were used to study water mixing in the Paraíba do Sul River estuary region in August 2007 (dry season) and March 2008 (rainy season) and to evaluate the reach of the river plume in the direction of the open ocean. Two sampling campaigns were carried out, each in a different season. Based on these results, it was possible to conclude that the multitracers used in this study (salinity, Si, Ba and U, as well as the radium isotopes 223Ra, 224Ra, 226Ra and 228Ra) presented satisfactory results toward defining the plume reach and determining the residence time and water-mixing processes in the estuary. A strong correlation was observed between tracers and the distance to the coast. During the low river water discharge period, the riverine water took about 10 days to reach open ocean waters (salinity ∼ 35). During the rainy period this value decreased to 6 days. Based on the radium results, it was possible to calculate diffusion coefficients (Kh) of 23 km2 d−1 and 38 km2 d−1 for 224Ra and 223Ra, respectively, during the dry season (winter). Values of 65 km2 d−1 and 68 km2 d−1 for 223Ra and 224Ra, respectively, were found for the rainy period (summer).  相似文献   
457.
Plant responses to abiotic stress can alter their response to biotic stress. We examined changes in the activity of several defense proteins in response to powdery mildew infection of garlic mustard (Alliaria petiolata) in the greenhouse and in the field. Second, we examined the effects of water limitation on the same defense protein responses, as well as on total soluble protein and glucose concentration, plant growth, and powdery mildew disease development. Similar increases in the activity of peroxidase, chitinase, and β-1-3-glucanase were observed in leaves of plants with substantial powdery mildew disease in both greenhouse- and field-grown plants. In the greenhouse, activities of chitinase and peroxidase as well as total soluble protein and glucose concentrations generally increased with the degree of water limitation. In turn, leaf growth and powdery mildew symptom development decreased as the degree of water limitation increased. This study revealed that plant chemical responses to water limitation and powdery mildew disease can overlap to a large extent, which, in addition to changing microenvironmental conditions and other indicators of plant quality, may underlie the ability of water limitation to inhibit powdery mildew disease symptom development in this wild plant pathosystem.  相似文献   
458.
In this paper, we compare the populations of the Lusitanian toadfish Halobatrachus didactylus along the Portuguese shore, using a putative fragment of the mitochondrial control region and the first intron of the S7 ribosomal protein gene. This demersal species ranges from the tropical West African coast to the Iberian Peninsula and the Mediterranean, having its northern limit in the Tagus River. For the putative control region, a single haplotype occurs in all fish from Tagus and Sado (the location immediately to the south) with a clear increase in diversity to the South, peaking at Algarve (south Portugal). The data seem to point to a very recent Holocenic colonization of Tagus and Sado from the South (possibly Algarve). We suggest that even small oscillations in sea surface temperature (SST) may cause local extinctions and subsequent recolonizations in populations of thermophilic fish that are at the cold limit of their distributions.  相似文献   
459.
Co-digestion of food waste with dairy manure is increasingly utilized to increase energy production and make anaerobic digestion more affordable; however, there is a lack of information on appropriate co-digestion substrates. In this study, biochemical methane potential (BMP) tests were conducted to determine the suitability of four food waste substrates (meatball, chicken, cranberry and ice cream processing wastes) for co-digestion with flushed dairy manure at a ratio of 3.2% food waste and 96.8% manure (by volume), which equated to 14.7% (ice-cream) to 80.7% (chicken) of the VS being attributed to the food waste. All treatments led to increases in methane production, ranging from a 67.0% increase (ice cream waste) to a 2940% increase (chicken processing waste) compared to digesting manure alone, demonstrating the large potential methane production of food waste additions compared to relatively low methane production potential of the flushed dairy manure, even if the overall quantity of food waste added was minimal.  相似文献   
460.
For decades, several native medicinal species have been used by the pharmaceutical industry in Brazil to create commercial products. In 1995, the Ministry of Health, following the recommendations of the World Health Organization, established herbal regulations (RDC 17) in order to improve the quality of such products. In fact, only plant species with conclusive results from pharmacological and toxicological studies can be used for creating medicines. In this study, we evaluated the consequences of RDC 17 on the use and conservation of native medicinal plants by comparing the plant material used by six companies in 1995/1996 and 10 years later (2005/2006). Eighty-three different species were used in 1995/1996, 50 of them native (60.2%), 16 exotic (19.3%), and 17 imported (20.5%). In 2005/2006, 44 species were used by the companies and only 19 (43.2%) were native. The category of plant material that saw the largest decrease in use was roots, and in 2005/2006 leaves were more used. The study shows a strong reduction in the collection of native species signalizing the importance of herbal regulations on their conservation. It also points to the need for pharmacological and toxicological studies of the Brazilian native medicinal flora, as well as studies on their ecology and conservation.  相似文献   
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