5,855 research outputs found
Lâhorticulture et lâarboriculture fruitiĂšres au QuĂ©bec
Lâhistoire de lâhorticulture et de lâarboriculture fruitiĂšres au QuĂ©bec sâinscrit dans le champ plus vaste des rapports sociaux Ă la nature et dans celui de la production des paysages domestiques. On tente dâabord de cerner les perceptions des EuropĂ©ens Ă lâĂ©gard de la nature sauvage et de ses ressources, pour mieux comprendre ensuite leurs motivations Ă introduire en Nouvelle-France les espĂšces fruitiĂšres qui leur sont les plus familiĂšres. Plusieurs faits culturels inĂ©dits apparaissent ainsi au fil de lâanalyse des sources variĂ©es, entre autres lâapport majeur des communautĂ©s religieuses et celui des prĂȘtres missionnaires qui vont manifestement utiliser lâhorticulture et lâarboriculture fruitiĂšres pour sĂ©dentariser et mieux Ă©vangĂ©liser les AmĂ©rindiens nomades. LâĂ©ducation et la conduite des arbres fruitiers comportent dans la tradition chrĂ©tienne des valeurs morales Ă©videntes : elles illustrent la victoire du bien sur le mal, en plus de participer Ă la quĂȘte de lâexcellence et Ă la louange du CrĂ©ateur. LâaccessibilitĂ© croissante du nouvel Ă©dulcorant quâest le sucre dâĂ©rable a aussi menĂ© les habitants du pays neuf Ă dĂ©velopper des habitudes alimentaires originales favorisant la consommation des fruits frais et en conserves. Finalement, la proximitĂ© et la domination agressive de la grande industrie agroalimentaire Ă©tatsunienne ont littĂ©ralement entraĂźnĂ© la production fruitiĂšre quĂ©bĂ©coise dans une mouvance productiviste Ă compter de la fin du 19eet du tournant du 20e siĂšcle, faisant disparaĂźtre les vergers de prunes, de cerises, de poires, de pĂȘches et de raisins. Ne survivent aujourdâhui, et encore difficilement, que les producteurs de petits fruits en zone pĂ©riurbaine et les pomiculteurs, menacĂ©s Ă leur tour par les importations venant cette fois de Nouvelle-ZĂ©lande et de Chine.Fruit growing history belongs to a wider field of social relations to nature and the making of domestic landscape. The way the Europeans perceived the wilderness helps us to understand the reasons of introducing familiar species and varieties of fruits. Many cultural facts emerge from the study of diversified sources, such as the role of the missionnaries who used the practice of fruit growing and gardening to sedentarize the Amerindians. Thus the long christian tradition of fruit growing symbolize the victory of the good being and manners over the bad one. Another fact concern the constant progress of sweet meals in the common regime of people due to the growing use of the maple sugar. At least, the development of a real continental fruit market, very near and closely related to the Montreal fruit producers finally caused the rapid abandon of many ancient culture such as plums, pears, peaches, cherries and table grapes. Today, even the apple growers must deal with the agressive marketing of fruits, now coming from so far as New Zealand and China
Architecture domestique et habitat rural de la Nouvelle-France
La production du paysage agricole dans le Nouveau monde a Ă©tĂ© une entreprise de trĂšs longue haleine, remplie dâembĂ»ches et parsemĂ©e de tant de difficultĂ©s imprĂ©vues quâelle a obligĂ© chacun des colons venus de France Ă revoir et adapter ses pratiques usuelles, voire Ă adopter de nouvelles stratĂ©gies dâĂ©tablissement
Log-normal Star Formation Histories in Simulated and Observed Galaxies
Gladders et al. have recently suggested that the star formation histories (SFHs) of individual galaxies are characterized by a log-normal function in time, implying a slow decline rather than rapid quenching. We test their conjecture on theoretical SFHs from the cosmological simulation Illustris and on observationally inferred SFHs. While the log-normal form necessarily ignores short-lived features such as starbursts, it fits the overall shape of the majority of SFHs very well. In particular, 85% of the cumulative SFHs are fitted to within a maximum error of 5% of the total stellar mass formed, and 99% to within 10%. The log-normal performs systematically better than the commonly used delayed-Ï model, and is superseded only by functions with more than three free parameters. Poor fits are mostly found in galaxies that were rapidly quenched after becoming satellites. We explore the log-normal parameter space of normalization, peak time, and full width at half maximum, and find that the simulated and observed samples occupy similar regions, though Illustris predicts wider, later-forming SFHs on average. The ensemble of log-normal fits correctly reproduces complex metrics such as the evolution of Illustris galaxies across the star formation main sequence, but overpredicts their quenching timescales. SFHs in Illustris are a diverse population not determined by any one physical property of galaxies, but follow a tight relation, where width â (peak time)^(3/2). We show that such a relation can be explained qualitatively (though not quantitatively) by a close connection between the growth of dark matter halos and their galaxies
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