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71.
The degradation of 12 fungicides (azoxystrobin, cymoxanil, cyproconazole, cyprodinil, fenarimol, fludioxonil, iprovalicarb, mepanipyrim, penconazole, pyrimethanil, tolclofos-methyl, triadimenol), commonly used in pest management strategies on Sardinian greenhouse tomato crops was studied. A different residue behaviour was observed between the studied cultivar. On the smaller, a "cherry" type tomato, field data showed an initial residue mostly higher than the "beefsteak" tomato. In any case, except for penconazole, all pesticide residues were below their maximum residue levels (MRLs) reaching the pre-harvest interval (PHI). On both cultivar, triadimenol and cymoxanil residues completely disappeared reaching their PHI, while iprovalicarb, fenarimol, and fludioxonil disappeared in a time of 17 to 24 days. On the contrary, azoxystrobin, cyproconazole, cyprodinil, penconazole, tolclofos-methyl, mepanipyrim, and pyrimethanil showed a long persistence on both tested cultivar and may have residual problems due to an accumulation effect if repeated field treatments will be performed. The first group of molecules according to their rapid degradation could be used in low pesticide-input management in order to obtain tomatoes with low or no detectable residues.  相似文献   
72.
In the present study, Life Cycle Assessment (LCA) methodology was applied to evaluate the energy consumption and environmental burdens associated with the production of protected crops in an agricultural district in the Mediterranean region. In this study, LCA was used as a 'support tool', to address local policies for sustainable production and consumption patterns, and to create a 'knowledge base' for environmental assessment of an extended agricultural production area. The proposed approach combines organisation-specific tools, such as Environmental Management Systems and Environmental Product Declarations, with the environmental management of the district. Questionnaires were distributed to producers to determine the life cycle of different protected crops (tomatoes, cherry tomatoes, peppers, melons and zucchinis), and obtain information on greenhouse usage (e.g. tunnel vs. pavilion). Ecoprofiles of products in the district were also estimated, to identify supply chain elements with the highest impact in terms of global energy requirements, greenhouse gas emissions, eutrophication, water consumption and waste production. These results of this study enable selection of the 'best practices' and ecodesign solutions, to reduce the environmental impact of these products. Finally, sensitivity analysis of key LCA issues was performed, to assess the variability associated with different parameters: vegetable production; water usage; fertiliser and pesticide usage; shared greenhouse use; substitution of plastics coverings; and waste recycling.  相似文献   
73.
Degradation of two fungicides (cyprodinil and fludioxonil) and two insecticides (cyfluthrin and pymetrozine) applied on iceberg and romaine lettuce under field conditions with different methods (portable mistblower and chemigation) was studied field data showed that both distribution methods and lettuce cultivar affect the degradation trends of examined pesticides. In these trials the residues of all active ingredients after pre-harvest time were less than fifty's maximum residue levels; the values in the romaine cultivar were generally higher than those in iceberg lettuce. After pre-harvest time residues of pesticides applied on romaine lettuce by portable motor sprayer were always higher than those obtained by the chemigation system.  相似文献   
74.
Polymer blends between lignin, a natural, widely available, no-cost material, and Poly(ε-caprolactone) (PCL), a biodegradable polymer, have been prepared using the ‘clean’, friendly to the environment, technique of the High Energy Ball Milling (HEBM). Two kinds of lignin have been used, Straw lignin, obtained through the Steam Explosion process (SE lignin), and/or Lignosulphonated one (LS lignin). The tensile mechanical tests have shown that, at certain specific compositions, the blends, in particular those with both SE and LS lignin, have good mechanical properties. In particular, by varying the blend composition it is possible to obtain materials with tuneable properties, therefore useful for different applications. Dynamic-Mechanical-Thermal Analysis (DMTA) reveals substantial immiscibility of the blends. Experiments of UV irradiation show that lignin acts as an UV stabilizer for PCL. The effect is higher with SE lignin, likely due to its low molecular weight, which allows the short lignin chains to diffuse more easily within the amorphous regions of PCL.  相似文献   
75.
Falco biarmicus feldeggii is one of the most threatened taxa in Europe. Its global population is estimated at a few hundred pairs unequally scattered in a vast and fragmented area stretching from Sicily to the Caspian Sea. Most recent counts showed that Italy hosts a large part (>25%) of the whole population. Consequently, Italian authorities promoted a national action plan. In this framework, we carried out the first national survey for the Lanner Falcon in Italy (2003-2004). Our study area covered the whole breeding range, i.e., Sicily and the Italian peninsula (n = 2909 cells 10 x 10 km). When possible, we considered also additional information from previous regional investigations (1993-2001). First, we estimated size and distribution of each breeding subpopulation. Then, we tried to identify, at landscape level, the main environmental features linked to the spatial distribution of the nesting sites. We found the Lanner Falcon in 184 cells (6.4% of the total grid map), but we estimated no more than 140-172 pairs (70-80 of which are in Sicily) in the same breeding season. Higher levels of isolation characterize the continental breeding cells whereas in Sicily cells are much more clustered. Altitude is the main factor influencing cell aggregations in Italy; nevertheless, other environmental variables, such as climate, precipitation, and vegetation may be important. Our results show that the conservation measures adopted in Italy are somewhat inadequate given the low number of breeding pairs included in protected areas (23%-28%). Many small and scattered special areas of conservation (SAC) devoted to conserve priority habitats fit the irregular spatial aggregations of Lanner Falcon sites better than several large special protection areas (SPA).  相似文献   
76.
Environmental Science and Pollution Research - In recent years, the proliferation of Harmful Cyanobacterial Blooms (CyanoHABs) has increased with water eutrophication and climate change, impairing...  相似文献   
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79.
The results obtained in the four seasonal cruises planned in the PRISMA II project are reported. These concern dissolved and colloidal organic carbon, free amino acids and total dissolved carbohydrates and heterotrophic activity. Main factors controlling organic matter degradation, resulting from laboratory tests not planned in the above project, are also discussed. Dissolved organic matter shows seasonal accumulation, which may be markedly different from year to year, and large contributions by colloidal and saccharide components. Heterotrophic activities play an important role in the carbon cycle, although laboratory runs highlight limitations caused by aging of organic matter and phosphorus deficiency.  相似文献   
80.
Feedstock and compost samples were collected from twenty composting plants and analysed from the microbiological point of view. Faecal indicator organisms were determined in order to evaluate the efficacy of processes for the removal of pathogenic micro-organisms with similar survival characteristics and to verify their suitability as appropriate markers of microbial quality of composted products. In addition to the classical bacterial indicators, selected organisms, such as Salmonella, Giardia, Cryptosporidium, Clostridium spores and helminth ova, were investigated. Statistically significant differences in the removal of the different micro-organisms were observed with regard to both the different composting plants (P < 0.05) and feedstock composition (P < 0.05). In fact, compost obtained by feedstock containing sewage sludge was shown to have a better hygienic quality in comparison with compost containing green discards and municipal solid waste as raw matter. Giardia cysts, Cryptosporidium oocysts and helminth ova were not effective indicators of hygienic quality of compost, whereas Clostridium perfringens spores, because of their high resistance to treatments, could be considered as an additional model for assessing the composting process, especially with regard to more resistant pathogen reduction.  相似文献   
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