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José Maria Villela Pádua Kaio Olímpio Das Graças Dias Maria Marta Pastina João Cândido de Souza Valéria Aparecida Vieira Queiroz Rodrigo Veras da Costa Maria Beatriz Pereira da Silva Carlos Alexandre Gomes Ribeiro Claudia Teixeira Guimarães Salvador Alejandro Gezan Lauro José Moreira Guimarães 《Euphytica》2016,211(3):277-285
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Nuno Figueiredo Corina Carranca Henrique Trindade José Pereira Piebiep Goufo João Coutinho Paula Marques Rosa Maricato Amarilis de Varennes 《Paddy and Water Environment》2015,13(4):313-324
The present field experiment was conducted during two consecutive cropping seasons in central Portugal to study the effects of simultaneous elevation of carbon dioxide concentration ([CO2]) (550 μmol mol?1) and air temperature (+2–3 °C) on japonica rice (Oryza sativa L. “Ariete”) yield, crop duration, and SPAD-values across the seasons compared with the open-field condition. Open-top chambers were used in the field to assess the effect of elevated air temperature alone or the combined effect of elevated air temperature and atmospheric [CO2]. Open-field condition was assessed with randomized plots under ambient air temperature and actual atmospheric [CO2] (average 382 μmol mol?1). Results obtained showed that the rice “Ariete” had a moderate high yielding under open-field condition, but was susceptible to air temperature rise of +2–3 °C under controlled conditions resulting in reduction of grain yield. The combined increase of atmospheric [CO2] with elevated air temperature compensated for the negative effect of temperature rise alone and crop yield was higher than in the open-field. SPAD-readings at reproductive stage explained by more than 60 % variation the straw dry matter, but this finding requires further studies for consolidation. It can be concluded that potential increase in air temperature may limit rice yield in the near future under Mediterranean areas where climate change scenario poses a serious threat, but long term field experiments are required. 相似文献
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Angelia S. M. Vanderlaan Alex R. Hanke Joël Chassé John D. Neilson 《Fisheries Oceanography》2014,23(1):83-100
The Atlantic bluefin tuna (Thunnus thynnus) population in the western Atlantic supports substantial commercial and recreational fisheries. Despite quota establishment and management under the auspices of the International Commission for the Conservation of Atlantic Tunas, only small increases in population growth have been estimated. In contrast to other western bluefin tuna fisheries indices, contemporary estimates of catch per unit effort (CPUE) in the southern Gulf of St. Lawrence have increased rapidly and are at record highs. This area is characterized by the Cold Intermediate Layer (CIL) that is defined by waters <3°C and located at depths of 30–40 m in September. We investigated the influence of several in situ environmental variables on the bluefin tuna fishery CPUE using delta‐lognormal modelling and relatively extensive and consistent oceanographic survey data, as well as dockside monitoring and mandatory logbook data associated with the fishery. Although there is considerable spatial and temporal variation of water mass characteristics, the amount of available habitat in the southern Gulf of St. Lawrence (assuming a > 3°C thermal ambit) for bluefin tuna has been increasing. The percentage of the water column occupied by the CIL was a significant environmental variable in the standardization of CPUE estimates. There was also a negative relationship between the spatial extents of the CIL and the fishery. Properties of the CIL account for variation in the bluefin tuna CPUE and may be a factor in determining the amount of available feeding habitat for bluefin tuna in the southern Gulf of St. Lawrence. 相似文献
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Arbutus unedo L. (strawberry tree, Ericaceae) is a woody species with a circum-Mediterranean distribu-tion. It has considerable ecological relevance in southern... 相似文献
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D.H. Kim P.N. Seong S.H. Cho J.H. Kim J.M. Lee C. Jo D.G. Lim 《Livestock Science》2009,120(1-2):96-102
Current study investigated the effect of feeding systems (conventional vs organic rearing) on carcass characteristics, meat quality and fatty acid composition of Musculus longissimus dorsi of Korean native black barrows (KNP). Thirty pigs were reared under a conventional feeding system at indoor area of 1 m2 per head, while another thirty pigs were fed an indoor area with organic saw dusts of 1 m2 and an outdoor area with free ranges of 1 m2 for each pig for organic system. Diet for the organic rearing was also provided according to the guideline for organic pork products. Warner–Bratzler shear force was lower and water holding capacity was higher for pork produced under the organic guidelines. However, pork produced by an organic system did not affect sensory traits compared to pork produced by a conventional one. In addition, longissimus muscle from organically reared pigs had significantly (P < 0.05) higher myoglobin content and consequently higher CIE a?-values compared with those for the conventionally-reared pigs (P < 0.05). The organic pork resulted in significantly (P < 0.05) higher polyunsaturated fatty acid (PUFA) and unsaturated fatty acid contents, as well as a higher n-3 PUFA than the conventional one (P < 0.05). 相似文献