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1.
Glob Chang Biol ; 24(2): e485-e495, 2018 02.
Article in English | MEDLINE | ID: mdl-28892277

ABSTRACT

Large wild ungulates are a major biotic factor shaping plant communities. They influence species abundance and occurrence directly by herbivory and plant dispersal, or indirectly by modifying plant-plant interactions and through soil disturbance. In forest ecosystems, researchers' attention has been mainly focused on deer overabundance. Far less is known about the effects on understory plant dynamics and diversity of wild ungulates where their abundance is maintained at lower levels to mitigate impacts on tree regeneration. We used vegetation data collected over 10 years on 82 pairs of exclosure (excluding ungulates) and control plots located in a nation-wide forest monitoring network (Renecofor). We report the effects of ungulate exclusion on (i) plant species richness and ecological characteristics, (ii) and cover percentage of herbaceous and shrub layers. We also analyzed the response of these variables along gradients of ungulate abundance, based on hunting statistics, for wild boar (Sus scrofa), red deer (Cervus elaphus) and roe deer (Capreolus capreolus). Outside the exclosures, forest ungulates maintained higher species richness in the herbaceous layer (+15%), while the shrub layer was 17% less rich, and the plant communities became more light-demanding. Inside the exclosures, shrub cover increased, often to the benefit of bramble (Rubus fruticosus agg.). Ungulates tend to favour ruderal, hemerobic, epizoochorous and non-forest species. Among plots, the magnitude of vegetation changes was proportional to deer abundance. We conclude that ungulates, through the control of the shrub layer, indirectly increase herbaceous plant species richness by increasing light reaching the ground. However, this increase is detrimental to the peculiarity of forest plant communities and contributes to a landscape-level biotic homogenization. Even at population density levels considered to be harmless for overall plant species richness, ungulates remain a conservation issue for plant community composition.


Subject(s)
Biodiversity , Forests , Plants/classification , Animals , Deer/physiology , France , Herbivory , Population Density , Soil , Sus scrofa/physiology
3.
J Hist Med Allied Sci ; 66(4): 546-70, 2011 Oct.
Article in English | MEDLINE | ID: mdl-21037320

ABSTRACT

By focusing on funding methods, this paper considers the way in which medical research eventually led to the science-based medicine that is prevalent in France today. This process seems to have taken place in three stages during the second half of the twentieth century. In the 1940s and 1950s, two major events occurred. The first was the creation of a national health insurance fund in France, which opened up new reasons for, and ways of, funding medical research. The second was the development of antibiotics, which triggered a revival of clinical medicine. In the 1960s and 1970s, a proactive government science policy allowed the life sciences and medical research to come together in the wake of a burgeoning new science: molecular biology. Thus, in 1964, the creation of the National Health and Medical Research Institute (Institut national de la santé et de la recherche médicale or INSERM), destined to "molecularize" medical research, was seen as the fulfillment of the government's ambitious research policy. Today, with medicine irreversibly embedded in scientific and technical rationality, health has become a major issue in modern societies. This paper therefore touches on some of the key features of biomedical research, including the revival of funding systems for clinical research and the development of a system of research grants that was made possible by patient organizations and the creation of new funding agencies.


Subject(s)
Academies and Institutes/history , Biomedical Research/history , Research Support as Topic/history , Bibliometrics , Biological Science Disciplines/economics , Biological Science Disciplines/history , Biomedical Research/economics , France , Genomics/history , History, 20th Century , National Health Programs/history , Social Medicine/history
4.
Tree Physiol ; 25(11): 1437-46, 2005 Nov.
Article in English | MEDLINE | ID: mdl-16105811

ABSTRACT

We studied the effects of two fertilization treatments (N and NPKCa) on wood nitrogen (N) isotope composition (delta(15)N), water-use efficiency (WUE) estimated by carbon isotope composition (delta(13)C) analyses, and ring width of trees in 80-year-old beech (Fagus sylvatica L.) stands in the forest of Fougères, western France. Four replicates were fertilized in two successive years (1973 and 1974), 20 years before core sampling. Unfertilized control trees displayed a decreasing delta(15)N trend with time. The N and NPKCa treatments both increased delta(15)N compared with the control treatment. Wood extraction by organic solvents enhanced the delta(15)N signal. Thus, N addition to the beech ecosystem, even in moderate amounts, could be traced back in tree-ring delta(15)N, suggesting that wood N isotope analysis is a promising tool for studying the long-term effects of N deposition on forests. Although WUE decreased for about 6 years after N fertilization, WUE in NPKCa-treated trees did not differ significantly from that in control trees. Results were similar whether based on cellulose or total wood delta(13)C analysis, suggesting that extraction of cellulose is not necessary when studying fertilization impacts on WUE. The NPKCa treatment had a large impact on radial growth, causing a significant long-lasting increase of 29% compared with the control treatment. Nitrogen alone did not change radial growth significantly.


Subject(s)
Fagus/growth & development , Trees/growth & development , Carbon Isotopes , Fertilizers , Nitrogen Isotopes , Plant Stems/growth & development , Soil
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