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  • 1
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    Sociologie et normativité scientifique (2021)
    Presses universitaires du Midi
    Details
    Publication Date: 2023-12-20
    Description: La question de la capacité de la sociologie à se constituer comme science est banale et revient régulièrement. Comme souvent dans un tel cas, la multiplicité des réponses obscurcit d’autant plus le débat que chacun le croit définitivement tranché et se sent autorisé à camper sereinement sur ses positions. Le dossier est ici à nouveau ouvert, dans une perspective non plus polémique mais analytique. L’idée de normativité scientifique – c’est-à-dire de système de normes commentant l’activité des chercheurs – en est le fil conducteur. Divers auteurs, sociologues pour la plupart, mais aussi philosophe comme Gilles Gaston Granger ou Pierre Livet, ont accepté de confronter des points de vue issus des diverses traditions et pratiques de la recherche sociologique. Quantitativisme et qualitativisme, phénoménologie et positivisme, ces étiquettes qui, parmi tant d’autres, définissent souvent des camps retranchés et des langages irréductibles, ne sont ici que des positions également pertinentes à partir desquelles les divers auteurs engagent le dialogue. L’enjeu n’est pas de consacrer le triomphe d’une approche sur une autre ni de mettre en scène une sociologie rêvée, mais de procéder au travail commun de réflexivité qu’exige son exercice quotidien.
    Keywords: H1-99 ; science ; norme ; sociologie ; bic Book Industry Communication::H Humanities
    Language: French
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    E-BOOK
  • 2
    Electronic Resource
    Electronic Resource
    Additive effects of genotype, nutrient availability and type of tissue damage on the compensatory response of Salix planifolia ssp. planifolia to simulated herbivory (1996)
    Springer
    Oecologia 107 (1996), S. 373-378 
    Details
    ISSN: 1432-1939
    Keywords: Nutrient addition ; Plant compensation ; Plant tolerance ; Relative growth rate ; Stomatal resistance
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Plant responses to herbivory include tolerance (i.e. compensatory growth) and defense. Several factors influence the tolerance of a plant following herbivory, including plant genetic identity, site nutrient availability, and previous and/or concurrent herbivory. We studied the effects of these factors on the compensatory response of Salix planifolia ssp. planifolia, a shrub species common in the boreal and subarctic regions of North America. We cloned several genets of S. planifolia and submitted them to simulated root and/or leaf herbivory while varying the nutrient availability. Simulated leaf herbivory was more detrimental to the plant than simulated root herbivory, reducing both above- and below-ground tissue production. Leaf demography was unaffected by either simulated herbivory treatment. There was some compensatory growth following simulated leaf and root herbivory, but only the root compartment responded to increased nutrient availability. Simulated leaf herbivory increased leaf transpiration and reduced stomatal resistance, suggesting increased carbon fixation. The unexpected finding of the experiment was the absence of interactions among factors (genotype, nutrient availability and type of tissue damage) on the compensatory response of S. planifolia. These factors thus have additive effects on the species' compensatory ability.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00328454
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    Paper (German National Licenses)
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  • 3
    Electronic Resource
    Electronic Resource
    Seasonal variation and annual fluctuation in granite outcrop plant communities (1989)
    Springer
    Plant ecology 80 (1989), S. 25-35 
    Details
    ISSN: 1573-5052
    Keywords: Arenaria ; Competitive release ; Dominance shift ; Drought ; Sedum ; Senecio ; Southeastern USA ; Viguiera
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Permanent quadrats in granite outcrop plant communities allowed us to monitor seasonal variation and annual fluctuation in community structure. Seasonal species turn-over was significant in communities on shallow soil, but not in communities on deeper soil where seasonal dominance shifts were common. Exceptional meteorological events appeared to mediate phenomena of competitive release in some island communities. A decrease in the abundance of Arenaria uniflora in Lichen-annual island communities, following a spring drought, was correlated with an increase in the abundance of Sedum smallii, a shallower-soil species. Richness in Annual-perennial island communities was higher in spring 1985 than in 1984 or 1986, and this occurred as the dominant species, Senecio tomentosus, temporarily declined in importance following a severe drought in late summer 1984. Significant annual fluctuation in the cover of Viguiera porteri could also be related to variations in the summer precipitation regime. Overall, plant responses to drought were individualistic and depended largely on the timing of these meteorological events in relation to the life-stages and/or the physiological status of the plants.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00049138
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    Paper (German National Licenses)
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  • 4
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    Spring-flowering herbaceous plant species of the deciduous forests of eastern Canada and 20th century climate warming (2007)
    Canadian Science Publishing
    Details
    Publication Date: 2007-02-01
    Description: Increases in the emission of greenhouse gases, particularly during the second half of the 20th century, have been associated with climate warming at the global scale. High latitude areas have been reported to be particularly sensitive to such changes, with significant impacts on plant phenology. The objectives of the present study were to (i) estimate changes in the flowering dates of 18 spring-flowering herbaceous plant species typical of the deciduous forests of eastern North America in three areas of eastern Canada (Gatineau–Ottawa, Montréal, and Québec) from 1900 to 2000 and (ii) associate these changes with those of annual and spring local temperatures. My results show a 2–6 days advance in flowering date over 100 years, depending on the region considered (corresponding to a ~2–3 days advance per 1 °C); these values are somewhat lower than those published in other studies, but still support the increasing body of literature on the effects of climate warming on plant phenology. Shifts in flowering phenology were particularly evident for Montréal, a large metropolitan region; this suggests that global climate warming, and its effects on plant phenology, may be exacerbated by local conditions, particularly those associated with large urban areas. Furthermore, species-specific responses to climate warming, as those presented here, might lead to significant changes in community composition and ecosystem functions.
    Print ISSN: 0045-5067
    Electronic ISSN: 1208-6037
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Published by Canadian Science Publishing
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  • 5
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    Nutrient availability and plant gender influences on the short-term compensatory response of Salix planifolia ssp. planifolia to simulated leaf herbivory (1999)
    Canadian Science Publishing
    Details
    Publication Date: 1999-01-01
    Print ISSN: 0045-5067
    Electronic ISSN: 1208-6037
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Published by Canadian Science Publishing
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  • 6
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    Growth patterns of sugar maple seedlings and mature trees in healthy and in declining hardwood stands (1990)
    Canadian Science Publishing
    Details
    Publication Date: 1990-07-01
    Description: Openings created in the forest canopy as a result of the decline of sugar maple (Acersaccharum Marsh.) may increase microsite heterogeneity and favor the growth of tree seedlings on the forest floor and possibly neighboring healthy trees because of resource release. To corroborate these hypotheses, I studied the growth of sugar maple seedlings and mature trees, and some microsite characteristics, in healthy and in declining hardwood stands. Sampling was carried out in 400-m2 quadrats in four stands of similar composition. In two of the stands, the trees showed no apparent symptoms of decline (healthy stands), but in the other two (declining stands), dieback had caused tree cover to be reduced by ≈25 to 30%. Photosynthetically active radiation below the canopy was significantly lower and less variable in the healthy than in the declining stands, under both cloudy and sunny conditions. In one of the declining stands, soil pH was higher and soil organic matter content was lower than in both healthy stands. Stem elongation of sugar maple seedlings did not differ among the stands prior to 1984, but following that date it was significantly higher and more variable among seedlings in the declining stands. Ring width of apparently healthy trees decreased markedly in the early 1980s and increased somewhat during the 1985–1987 period on the declining sites. Microsite heterogeneity and growth of tree seedlings on the forest floor were thus greater in the declining than in the healthy stands. Neighboring healthy trees did not necessarily respond to the opening of the canopy (as a result of dieback) by increased ring width; this possibly resulted from the hierarchical position within the canopy, the differential time of reaction, and the age and (or) the health status of each individual.
    Print ISSN: 0045-5067
    Electronic ISSN: 1208-6037
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Published by Canadian Science Publishing
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  • 7
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    Nutrient availability and plant gender influences on the short-term compensatory response of Salix planifolia ssp. planifolia to simulated leaf herbivory (1999)
    Canadian Science Publishing
    Details
    Publication Date: 1999-12-15
    Description: Males and females of dioecious plants often differ in their biochemistry, physiology, morphology, and (or) ecology. For example, growth rates often are higher for males than for females. Because the ability of plants to compensate for herbivory frequently varies with growth rate, we may expect males and females of dioecious plants to differ in their compensatory ability (hypothesis 1). However, environmental factors such as nutrient availability may influence the expression of such a response (hypothesis 2). For example, low nutrient availability may reduce growth rate and thus restrict compensation. To test these hypotheses, I cloned male and female genets of Salix planifolia Pursh ssp. planifolia from a natural population in northeastern Canada. I then submitted the plants of each sex to two levels of simulated leaf herbivory in combination with two levels of nutrient availability. Contrary to the first hypothesis, plant gender had no significant effect on the compensatory response to simulated leaf herbivory. However, nutrient availability modulated the compensatory ability of plants of both sexes, therefore supporting hypothesis 2. Herbivory may thus be more detrimental to the performance of S. planifolia individuals in low-nutrient environments, such as on dunes or rock outcrops.
    Print ISSN: 0045-5067
    Electronic ISSN: 1208-6037
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Published by Canadian Science Publishing
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  • 8
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    Temporal variations in the rooting ability of cuttings of Populusbalsamifera and Salixplanifolia from natural clones–populations of subarctic Quebec (1993)
    Canadian Science Publishing
    Details
    Publication Date: 1993-12-01
    Description: Temporal variations in the rooting ability of cuttings from five clones of Populusbalsamifera L. and five populations of Salixplanifolia Pursh from the Great Whale River valley in subarctic Quebec were determined. Cuttings were sampled monthly from May through October and rooted in a greenhouse. Root number and length of the longest root per cutting were determined 35 days after planting. There were significant variations among the six sampling dates in the rooting potential of cuttings of both species. A higher percentage of cuttings formed adventitious roots in May and June before or shortly after bud break than later, during the growing season; root number and length followed a similar trend. There was an increase in the rooting ability of cuttings of both species towards the fall period. Salixplanifolia produced more roots per cutting than P. balsamifera early in the season (i.e., May and June), but later in the season the differences between the two species were not great; root length showed no such trend. Differences among clones–populations in the rooting potential of cuttings were large for both species. Coefficients of variation for root number were lower in spring than later, during the growing season, for both P. balsamifera and S. planifolia. Seasonal trends in coefficients of variation for root length were not as evident as for root number. These results have significant implications for site restoration in the Subarctic. To optimize the rooting ability of cuttings and minimize the differences among clones–populations in rooting potential, cuttings should be sampled early in the season before bud break or shortly thereafter.
    Print ISSN: 0045-5067
    Electronic ISSN: 1208-6037
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Published by Canadian Science Publishing
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  • 9
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    Fertilizing and mulching influence on the performance of four native woody species suitable for revegetation in subarctic Quebec (1994)
    Canadian Science Publishing
    Details
    Publication Date: 1994-12-01
    Description: Two plantations were established in the village of Whapmagoostui-Kuujjuaraapik to determine the effects of two types of fertilizer (fast or slow release) and two types of mulch (plastic or organic) on native woody species growth and survival in subarctic Quebec. In the first plantation, the species tested were Salixplanifolia Pursh, Alnuscrispa (Ait.) Pursh, Piceaglauca (Moench) Voss, and Pinusbanksiana Lamb. Four growing seasons after planting, cuttings of S. planifolia had the highest survival of all four species (96% in control plots) and a very good growth (4.8 mm and 5.7 cm growth in diameter and height, respectively). The performance of A. crispa was also very good (77% survival in control plots; 5.1 mm and 7.5 cm growth in diameter and height, respectively), while Piceaglauca (17% survival in control plots; 0.6 mm and −9.0 cm growth in diameter and height, respectively) and Pinusbanksiana (31% survival in control plots; 2.4 mm and 5.7 cm growth in diameter and height, respectively) performance was poor. The application of a slow-release fertilizer enhanced plant growth of all four species, but reduced the survival of A. crispa, particularly when a plastic mulch was used. Otherwise, mulching had no significant effect on either growth or survival of any of the other species. In the second plantation, established on a more exposed site, the survival of S. planifolia was lower (77% in control plots) than in the first plantation, and the application of a fast-release fertilizer there had a negative effect on plant growth. These latter results appear to be related to freezing injuries and winter killing of vegetative buds. Organic mulching did not influence plant growth on this second site, but the utilization of Alnus wood chips increased the survival of S. planifolia cuttings. We recommend the use of S. planifolia and also of A. crispa for revegetation purposes in subarctic Quebec. Application of a slow-release fertilizer can increase plant growth, but should not be combined with the use of plastic mulches, as plant survival is then negatively affected.
    Print ISSN: 0045-5067
    Electronic ISSN: 1208-6037
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Published by Canadian Science Publishing
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  • 10
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    The spatial pattern of a Juniperus communis var. depressa population on a continental dune in subarctic Québec, Canada (1999)
    Canadian Science Publishing
    Details
    Publication Date: 1999-04-01
    Description: We performed a nearest-neighbor analysis to determine the population dispersion pattern and the association between males and females in a Juniperus communis L. var. depressa Pursh population occupying a continental dune in subarctic Quebec, Canada. The overall dispersion pattern was contagious, and males (or females) were proportionately as likely to have a male as they were to have a female nearest neighbor. Crown size was positively related to nearest-neighbor distance for the male-male comparison only, suggesting a somewhat stronger intrasex competition between males. Nearest-neighbor distance increased with crown size (significantly related to age) suggesting a change in the intensity of aggregation with age possibly related to self-thinning. Higher mortality as a result of stronger male-male competition could explain the female-biased sex ratio and the absence of spatial segregation between sexes. The overall contagious dispersion pattern in the population may be related to the fact that most seed cones fall directly underneath the mother plant. Birds can eat the cones of J. communis and thus disperse seeds. However, these seeds are deposited in clumps, a process that may also explain contagion within the population.
    Print ISSN: 0045-5067
    Electronic ISSN: 1208-6037
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Published by Canadian Science Publishing
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