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221.
Cristina Dutra Vieira Maria Auxiliadora Roque de Carvalho Noil Amorim de Menezes Cussiol Maria Eugênia Alvarez-Leite Simone Gonçalves dos Santos Renata Maria da Fonseca Gomes Marcos Xavier Silva Luiz de Macêdo Farias 《Waste management (New York, N.Y.)》2009,29(4):1388-1391
When developing proper waste management strategies, it is essential to characterize the volume and composition of solid waste. The aim of this work was to evaluate the composition of dental waste produced by three dental health services in Belo Horizonte, Minas Gerais State, Brazil. Two universities, one public and one private, and one public dental health service were selected. Waste collection took place from March to November 2007. During this period, three samples were collected from each dental health service. The total amount of dental waste produced in one day of dental work was manually separated into three categories: infectious and potentially infectious waste, accounting for 24.3% of the total waste; non-infectious waste, accounting for 48.1%; and domestic-type waste, accounting for 27.6% (percentages are for mean weights of solid waste). Our results showed that most of the waste considered as biomedical may be misclassified, consequently making the infectious waste amount appear much larger. In addition, our results suggest that the best waste minimization method is recycling, and they help to define an appropriate waste management system in all three of the dental health services involved in this study. 相似文献
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Rui Lourenço Vincenzo Penteriani Maria del Mar Delgado Michela Marchi-Bartolozzi João Eduardo Rabaça 《Behavioral ecology and sociobiology》2011,65(9):1709-1714
Intraguild predation (IGP) has been explained in terms of competitor-removal, food-stress and predator-removal hypotheses.
Only the first two hypotheses have been fairly well studied. To test the predator-removal hypothesis as a force determining
IGP in avian predators, we performed a field experiment to simulate the presence of an IG predator (eagle owl Bubo bubo dummy) in the surrounding of the nests of four potential IG prey (black kite Milvus migrans, red kite Milvus milvus, booted eagle Aquila pennata and common buzzard Buteo buteo). To discard the possibility that an aggressive reaction towards the eagle owl was not related to the presence of the IG
predator, we also presented a stuffed tawny owl Strix aluco, which is a potential competitor but cannot be considered an IG predator of the studied diurnal raptors considered in the
experiment. While almost always ignoring the tawny owl, raptors chiefly showed an interspecific aggressive behaviour towards
their IG predator. Our results seem to support the predator-removal hypothesis, as the IG prey may take advantage of the diurnal
inactivity of the IG predator to remove it from their territory. However, the recorded behaviour may be also considered as
a special variety of mobbing (i.e. a prey’s counter-strategy against its predator), where the mobber is sufficiently powerful
to escalate predator harassment into deliberate killing attempts. In their turn, eagle owls can respond with an IG predatory
behaviour aimed at removing IG prey species which are highly aggressive mobbers. 相似文献
223.
Nicolae Scarlat Milan Martinov Jean-François Dallemand 《Waste management (New York, N.Y.)》2010,30(10):1889-1897
This paper provides a resource-based assessment of the available agricultural crop residues for bioenergy production in the European Union, at the level of the 27 Member States. The assessment provides the amount of the residues produced, collected, their present uses and the residues left available for bioenergy. This study considers the crop production and yields and multi-annual yield variation for each crop. The calculation was based on specific residues to product ratios, which were determined, depending on the crop type and crop yield. Sustainable removal rates were considered in order to protect soil fertility. The results show large spatial and temporal variations of available crop residues within EU27. The average amount of crop residues available for bioenergy in EU27 was estimated at 1530 PJ/year, with a variation between 1090 and 1900 PJ/year. The average value represents about 3.2% in final energy consumption in the EU27 while the variation 2.3–4%. This variation, which is even larger at the level of Member States, may result in shortages in biomass supply in some years, when crop residues are available in a lower amount than the average. 相似文献
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Kamran Moradkhani Laurence Cuisset Pierre Boisseau Olivier Pichon Marine Lebrun Houda Hamdi-Rozé Marie-Laure Maurin Nicolas Gruchy Marie-Christine Manca-Pellissier Perrine Malzac Frédéric Bilan Marie-Pierre Audrezet Pascale Saugier-Veber Anne-Laure Fauret-Amsellem Chantal Missirian Paul Kuentz Gregory Egea Agnès Guichet Isabelle Creveaux Caroline Janel Ines Harzallah Renaud Touraine Carole Goumy Nicole Joyé Jacques Puechberty Emmanuelle Haquet Sandra Chantot-Bastaraud Sébastien Schmitt Philippe Gosset Bénédicte Duban-Bedu Bruno Delobel Philippe Vago François Vialard Denise Molina Gomes Jean-Pierre Siffroi Jean-Paul Bonnefont Jean-Michel Dupont Philippe Jonveaux Martine Doco-Fenzy Damien Sanlaville Cédric Le Caignec 《黑龙江环境通报》2019,39(11):986-992
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Franois Gillet Florian Kohler Charlotte Vandenberghe Alexandre Buttler 《Agriculture, ecosystems & environment》2010,135(1-2):34-41
Cattle activity greatly influences plant species composition and biomass production of grassland ecosystems. Dung deposition by cattle together with grazing and trampling can be considered as one of the important factors driving vegetation dynamics in pastures. The objective of this study was to investigate at 10-cm and 1-month resolution the plant community dynamics induced by dung deposition in two plant communities (a mesotrophic and an oligotrophic grassland) in a pasture of the Swiss Jura Mountains. Vegetation was sampled four or three times during the vegetation period in contiguous 10 cm × 10 cm quadrats from the centre of the dung pat to a distance of 60 cm. A lower grazing intensity near the dung pat was recorded for all observation periods. In the mesotrophic grassland the canopy was higher near the dung pat already one week after dung deposition. Vegetation around dung pats was submitted to two opposite fertilizing and grazing gradients, which induced changes in vegetation texture and structure at fine scale and short term. We observed a positive rank correlation between species turnover and distance to the dung for both communities, suggesting a seasonal stabilizing effect of dung on the plant composition of their direct surroundings (0–10 cm) likely due to cattle avoidance. Since dung pats are dropped every year in different locations, they create in the pasture a shifting mosaic of nutrient availability and grazing intensity inducing at seasonal scale micro-successions in plant communities. 相似文献
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