Dissertations / Theses on the topic 'Compétition de croissance'
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Dreyfus, Philippe. "Compétition et croissance dans de jeunes peuplements résineux. Aspects biologiques, écologiques et sylvicoles." Aix-Marseille 3, 1988. http://www.theses.fr/1988AIX30015.
Full textLarcher, Marièle. "Stimulation de la croissance du colza par Phyllobacterium sp. : mode d'action et impact de la compétition bactérienne." Montpellier, ENSA, 2002. http://www.theses.fr/2002ENSA0024.
Full textCruz, Pablo. "Relations de compétition dans une association luzerne-dactyle : étude des dynamiques de la croissance et des prélèvements d'azote." Paris 11, 1985. http://www.theses.fr/1985PA112210.
Full textThis work analyses intra and interspecific competition relations within an alfalfa (cv. Lutèce)-orchardgrass (cv. Lutetia) mixture and within corresponding pure stands. Dynamics of growth of aerial biomass and nitrogen uptake was studied along successive regrowths. We were not able to find any improvement of the grass nitrogen nutrition by the presence of the legume. Alfalfa proved strongly competitive for mineral nitrogen utilization in the periods of its rapid growth. Nitrogen given to the mixture is then actually absorbed by the species whose growth is faster at the time of leaf area establishment. Competition for light is the determining factor of the ability to respond nitrogen fertilization. Consequences on grass-legume mixtures utilization as forage crops are discus sed. The yield of the mixture can be enhanced by nitrogen fertilization, but this increases the utilization of mineral nitrogen by the legume and exaggerates the dominance of one partner on the other
Miquel, Jean-Charles. "Modélisation des effets de la compétition interspécifique et des pratiques sylvicoles sur la croissance de jeunes plants forestiers." Electronic Thesis or Diss., Paris, AgroParisTech, 2020. http://www.theses.fr/2020AGPT0003.
Full textPlanting is an interesting tool for implementing forest management strategies and is also a critical step in the forest management cycle. During this period, site preparation is very often used to ensure the success of the plantation by alleviating constraints such as competition from accompanying vegetation.Growth models have been widely used for many years and are effective tools for simulating the impact of silvicultural operations and competition. However, there is currently no tree growth model in France to assess or compare silvicultural operations carried out during young stages, even for commonly cultivated commercial species. Most of them are phenomenological models describing the dendrometric variables as a function of the technical characteristics of the silvicultural operations carried out. These models generally produce robust predictions that are difficult to extrapolate outside of their application conditions. Other models, said to be functional, are based on ecophysiological processes in order to estimate the growth of the seedlings but however require a number of parameters which can be difficult to obtain and, in addition, produce tree growth forecasts which are not always accurate. Hybrid models that combine measurement methods and ecophysiological methods are a promising approach that allows the use of functional relationships expressing tree growth while obtaining a robust prediction of growth.The eagle fern (Pteridium aquilinum L. Kuhn) is one of the problematic species for the success of young plantions. It reacts quickly to the opening of the canopy and is very competitive for the resources of the environment (especially water and light), thus being able to delay the development of young trees for several years
Bugnicourt, Ghislain. "Adhésion, croissance et polarisation de neurones sur substrats micro-et nano-structurés." Phd thesis, Université de Grenoble, 2011. http://tel.archives-ouvertes.fr/tel-00665074.
Full textGnanou, Nathalie. "Effet de la taille et de la composition de la population initiale sur la croissance de Listeria Monocytogenes." Compiègne, 2004. http://www.theses.fr/2004COMP1543.
Full textListeria Monocytogenes is a foodborne pathogen causing 20 to 30% lethality. A better knowledge of the parameters having an impact on its growth in food is of great importance in Listeria Monocytogenes quantitative risk analysis. Our objective was to evaluate the effect of Listeria spp. Population on L. Monocytogenes growth. It appeared that interactions between Listeria cells from the same strain or from different strains and species had a low impact on their growth. Nevertheless, the initial L. Monocytogenes population density influence the final contamination levels and the time necessary to attain this final concentration. Hence, it is an important factor to be taken into account in quantitative risk analysis. During this study, an enumeration method adapted to low L. Monocytogenes contamination levels was developped
Lesage, Isabelle. "Effets d'un gradient de lumière et de compétition intraspécifique sur la croissance et la morphologie de la cime du sapin baumier (Abies Balsamea (L.) Mill.)." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp04/mq25794.pdf.
Full textPineau, Adrian. "Modélisation 3D de structures de grains par une approche automate cellulaire. Application à la compétition de croissance dendritique et à la cristallisation du silicium polycristallin." Thesis, Paris Sciences et Lettres (ComUE), 2019. http://www.theses.fr/2019PSLEM042.
Full textGrains structures obtained during solidification processes strongly influence the properties of technical products. It is specially the case for cast parts in metallic alloys, or for silicon photovoltaic cells. The CA-FE (Cellular Automaton - Finite Elements) method aims to model grain structure evolution during solidification at a macroscopic scale, but also requires approximations at smaller scales. In this work, two distinct studies are proposed. First, CA simulations of growth competition among columnar dendritic grains are carried out for a succinonitrile-0.4 wt% acetone alloy. This is achieved by computing the grain goundary orientation during directional solidification. Comparisons are subsequently conducted with recent phase field results derived under the same conditions. An excellent agreement is found with phase field simulations results within arange of intermediate cell size centered around the maximum step between primary stationary dendrite tips of the two competing grains. The Esaka configuration, corresponding to a dendritic growth competition for a succinonitrile-1.3 wt% acetone alloy, is also studied. Polycristalline silicon growth was investigated within the ANR CrySaLID project. The CA method was enriched to allow facets growth and grains in twin relationship modeling. These developements use a geometrical approach based on in situ and ex situ experimental observations. The resulting numerical model was applied to experimental configurations and good qualitative and quantitative agreements were found. Simulations over a cubic and centimetric domain were lastly conducted. It was found that facets growth and twin nucleations strongly modify the grains structure compared to a dendritic microstructrure
Pinto, Paulina. "Ecologie et croissance de Abies alba Mill. en peuplements purs et mélangés dans le Massif Vosgien (Nord-est de la France)." Phd thesis, ENGREF (AgroParisTech), 2006. http://pastel.archives-ouvertes.fr/pastel-00003643.
Full textAdili, Boutheina. "Croissance, fructification et régénération naturelle des peuplements artificiels de Pin pignon (Pinus pinea L.) au nord de la Tunisie." Phd thesis, Université Blaise Pascal - Clermont-Ferrand II, 2012. http://tel.archives-ouvertes.fr/tel-00856265.
Full textCollet, Catherine. "Effet compétitif de deux graminées forestières sur des jeunes chênes sessiles en conditions contrôlées : interaction avec une sécheresse édaphique." Nancy 1, 1994. http://www.theses.fr/1994NAN10029.
Full textBuhler, Susanne. "Utilisation du seigle d'automne (Secale cereale) comme culture de couverture dans la lutte contre les mauvaises herbes dans la citrouille (Cucurbita pepo) au Québec." Thesis, Université Laval, 2009. http://www.theses.ulaval.ca/2009/26258/26258.pdf.
Full textBlandin-Morisot, Virginie. "Etude pharmacologique et fonctionnelle des antagonistes des récepteurs endothélines : mise en évidence d'inhibiteurs allostériques." Paris 11, 2001. http://www.theses.fr/2001PA11T14B.
Full textThe discovery of endothelins, potent vasoconstrictor peptides and nitric oxide at the end of the eighties point out a new role of the vascular endothelium. Endothelin-1 (ET-1) is mainly secreted by endothelial cells and acts via two G protein-coupled receptors, ET-A and ET-B. ET-1 is supposed to play an important role in several cardiovascular diseases and cancer. Consequently, pharmaceutical companies are interested in developping receptor antagonists but their action remains unclear in most cases. Actions of ET receptor antagonists have often be described as atypical, in the sense they cannot be interpreted using classical pharmacological reasonning. They have suggested existence of novel forms of receptors or of various forms of cross-talk mechanisms. The first part of this work was to demonstrate that atypical actions of receptor antagonists arise whenever second order binding conditions prevail. In instance BQ-123 insensitive actions of ET-1 can be documented in cells that express functional ET-A and ET-B receptors. One of the main properties of endothelin is its almost irreversible binding to its receptors. This simple fact limits the action of antagonists. The second part of this work was to show that it is possible to overcome the irreversibility of ET-1 binding by using allosteric inhibitors. Aspirin and salicylic acid are such inhibitors. A detailed structure activity relationship study led to identification of 3,5 dibromosalicylic acid as a potent allosteric inhibitor for ET-A receptors. It inhibits ET-1 binding in an apparently competitive manner and potentiates actions of true competitive receptor antagonists
Hébert, François. "Perspective écophysiologique de l'envahissement des éricacées dans le sous-domaine de la pessière noire à mousses de l'Est du Québec." Thesis, Université Laval, 2010. http://www.theses.ulaval.ca/2010/27303/27303.pdf.
Full textEricaceous shrubs are known to impair black spruce (Picea mariana (Mill.) [B.S.P.]) growth by creating a strong competition for below and aboveground resources. Opening of the forest canopy with harvest can intensify this competition and lead to enroachment of ericaceous shrub. Our objective was to explain, through evaluation response of functional traits, ericaceous potential enroachment after logging and stagnant growth of black spruce advance regeneration in the Quebec’s eastern black spruce-feathermoss sub-domain. The first chapter demonstrated the rapid acclimation of bog Labrador tea (Rhododendron groenlandicum [Oeder] Kron & Judd) to higher light availability created by logging, especially in the more intense treatements, through a modification of both physiological leaf traits. On the other hand, black spruce leaf traits did not respond to changes in environement associated with logging; this may indicate either an absence or a delay in acclimation. In a second field experiment, black spruce photosynthetic rate was negatively influenced by ericaceous shrub presence on the cutting area, regardless of the site fertility quality. The lower photosynthesis rate of black spruce, when associated with ericaceous shrubs, could be resulting of a lower mineral soil nitrogen availability created by a greater belowground competition for ressources form the ericaceous shrubs. A third experiment under greenhouse conditions showed that Rhododendron and Kalmia leaf mass per unit of area (LMA) was reduced by shading, but was similar for black spruce. There were few differences in trait response to N addition among species. Black spruce showed higher absorption rate and specific absorption rate at higher N levels, compared to the two ericads. Plasticity to light was higher for Kalmia (except for LMA) and plasticity for nitrogen addition was higher for Rhododendron black spruce suggesting that trait plasticity is in accordance with successional status of these species.
Mdawar, Ola. "Les accrus de frêne (Fraxinus excelsior L.) à l'interface environnement/sylviculture dans les Pyrénées Centrales : distribution spatiale et croissance." Thesis, Toulouse, INPT, 2009. http://www.theses.fr/2009INPT016A/document.
Full textThe changes of pastoral management practices in the Central Pyrenees are at the origin of the colonization process of grasslands by the ash (Fraxinus excelsior L.). This colonization process leads to the establishment of very dense and frequent patches of ashes in the Pyrenean landscape. The research is focused on the study of the current and future distribution of these forest patches resulting of the extension of ash trees by natural seeding called "the accrues" and on their potentiality of growth in relation to the nutritional factors which can be limiting from the point of view of an economic valorization of these new forest patches. The study of the tree growth was carried out on different levels: growth in height according to the fertility, and growth in diameter according to the climate and the competition. For this last factor, the growth was studied on in situ tree settlements without intervention and with two levels of thinning. The recognition of ash patches patterns within the mountain landscape was not possible using the traditional tools of remote sensing (SPOT) and should have require new technologies such as LIDAR or multispectral aero data which were out of reach during the PhD work. Exploratory field work has shown that at the landscape level, the presence of ash patches is a function of the topography and the land use history. With regard to the diameter growth of these increased, it is modulated by the strength of the trees, the level of competition and the climate. The maximum temperatures of April and the minimal temperatures of September or August influence the growth on the surface of tree ring. The ash reacts to the first year to thinning, especially for recent settlements and young trees. The effect of the mineral nutrition on the tree growth in height is not significant. The results on spatial pattern dynamics and the references on ash growth in a wide range of soil conditions obtained during this work constitutes a tool to help to manage ash patches within the studied area mainly with an economic point of view
Faivre, Robert. "Éléments de modélisation de la structure d'un peuplement de blé d'hiver avant installation de la compétition : étude des variations inter-plantes du mécanisme de tallage et de développement foliaire et modélisation de la croissance des talles." Paris 11, 1986. http://www.theses.fr/1986PA112367.
Full textThe modelling of wheat growth and development, before competition among plants occurs, is considered by means of the evolution of the stand structure. In chapter 1, we compare some simulation models. There are too much directed to model a mean behavior to be used here. In chapter 2, a data base is built after analyzing two DBMS. The management system is chosen with respect to the relational and partially hierarchical structure of our data. The tillering and the foliar development mechanisms are studied in chapter 3. An automatic clustering of plants is proposed. The robustness of the classes is computed. We cannot determine time-robust clusters. We define three types of plants according to the abortion of tillers T1 or T1p. The first leaf length, observed just after the emergence, discriminate quite well these groups. Except when tillers abort, the pattern of appearance of the leaves and tillers fits in well with the evolution of the foliar system. The deviations between observed and predicted foliar stages are lower than 1/2 leaf. The differences between types are small, except for tiller T1. In chapter 4, the potential growths in dry weight of successive tillers are compared for two types of plants. Several growth models were tried: the best one corresponds to a simple expression y=a exp(b T), whatever the tiller. Two methods for modelling the variance are compared; one in which the variance does not depend on the parameters a and b, another in which the variance is a function of the expectation. The main conclusions are : - b, the relative growth rate, increases with the rank of the tiller, and for homologous tillers, is slower for the plants whose tiller T1 has not developed - a is relatively stable for the first four primary tillers. - both methods for modelling the variance lead to similar results
Valdès, Gomez Hector. "Relations entre états de croissance de la vigne et maladies cryptogamiques sous différentes modalités d’entretien du sol en région méditerranéenne." Montpellier, ENSA, 2007. http://www.theses.fr/2007ENSA0012.
Full textMillien, Virginie. "Taille des incisives et structure de taille des communautés de rongeurs : aspects écologiques et évolutifs en milieu insulaire." Montpellier 2, 1999. http://www.theses.fr/1999MON20225.
Full textFruleux, Alexandre. "Développement racinaire du hêtre (Fagus sylvatica) en interaction avec d’autres espèces forestières et en fonction de la disponibilité en eau : conséquences sur la croissance et le fonctionnement hydrique et carboné." Thesis, Université de Lorraine, 2017. http://www.theses.fr/2017LORR0047/document.
Full textThe link between species diversity and ecosystem productivity is a central issue in ecology. Numerous studies have shown a positive relationship between forest diversity and productivity, as well as a greater resistance to various stresses such as droughts. On the other hand, few studies demonstrated the mechanisms behind the benefits observed in multi-species forests compared to monospecific ones. In particular, the role of belowground interactions among species in explaining the origin of positive effects of species diversity on ecosystem functioning is unknown. The aim of my PhD work was to study the influence of tree species interactions on the root development of beech (Fagus sylvatica) under different levels of water conditions. We showed that at the seedling stage, underground competition between beech, oak and pine was strong and that mixing these species could influence the growth of the beech. Water availability had a strong impact on the growth of beech seedlings, but the presence of seedlings of other species competing with beech did not particularly improve its response to drought. At the adult stage, in a forest plantation, we showed that maple trees competing with beech did not strongly modify the mean depth of soil water extraction of beech trees or the vertical distribution of beech roots. We conclude that (i) there was no separation of the underground ecological niches of these two species, both spatially and functionally (with respect to water acquisition), and (ii) that the mechanisms of belowground interaction between these two species do not seem to explain the origin of the higher productivity in the mixture than in the monoculture zone. Finally, the richest fungal communities were found in the mixed species zone: we hypothesize that greater fungal community richness in the mixture may improve water and nutrient acquisition and then contribute to higher productivity in the mixed species zone. My work suggests that underground interactions between beech and other forest species are probably not the main mechanism explaining beneficial effects of mixtures on productivity
Tandjaoui, Amina. "Solidification dirigée du silicium multi-cristallin pour les applications photovoltaïques : caractérisation in situ et en temps réel par imagerie X synchrotron." Thesis, Aix-Marseille, 2013. http://www.theses.fr/2013AIXM4319/document.
Full textWe studied in situ and real-time the grain structure of multi-crystalline silicon from directional solidification using synchrotron X-ray imaging techniques. X-ray Radiography gives information on the evolution, dynamics and morphology of the solid/liquid interface. X- ray Topography gives more information on the grain structure, strains and defects that occur during solidification step. We showed the importance of the preparation of the initial stage of solidification in particular in the experiments where solidification is initiated from seed. The analysis of the solid/liquid interface morphology allowed us to characterize the kinetic undercooling of the solidification front, to understand the evolution of the grains boundary grooves and to analyze the mechanisms of grain competition and also to reveal the impurities impact on the grain structure formed at the end of the solidification. We also observed twinning phenomenon in our experiments and we demonstrated that twins in multi-crystalline silicon can be growth twins. Two kinds of silicon twins have been identified and the grain competition phenomenon with twins studied
Guillemot, Joannès. "Productivity and carbon allocation in European forests : a process-based modelling approach." Thesis, Paris 11, 2015. http://www.theses.fr/2015PA112091/document.
Full textThe processes that underlie forest productivity and C allocation dynamics in trees are still poorly understood. Forest growth has for long been thought to be C limited, through a hypothesized causal link between C supply and growth (source control). This C-centric paradigm underlies most of the C allocation rules formalized in process-based models (PBMs). However, the source limitation of growth has been questioned by several authors, arguing that meristem activities are more sensitive than C assimilation to environmental stresses (e.g., water deficit and low temperatures). Moreover, the effect of management, which strongly affects forest functioning and wood growth, is not accounted for in most of the PBMs used to project the future terrestrial C sink. Our main objective in this thesis was to move forward into our understanding of the constraints that affect - or will affect - the wood productivity in European forests, from present to the end of the 21 st century. We addressed this objective through the improvement of the representation of the forest productivity and C allocation in the CASTANEA PBM, building on a detailed analysis of the key drivers of annual wood productivity in French forests over the last 30 years (the species studied are Fagus sylvatica, Quercus ilex, Quercus petraea, Quercus robur and Picea abies). Our results supported the premise that the annual wood growth of the studied species is under a complex control including both source and sink limitations. The inter-site variability in the fraction of C allocatedto stand wood growth was predominantly driven by an age-related decline. At the tree level, we showed that annual wood growth was well predicted by the individual size. The size-asymmetry of growth, i.e., the advantage of big trees in the competition for resources, increased consistently with the whole stand productivity at both inter-site and inter-annual scales. On the basis of our findings, we developed a new C allocation scheme in the CASTANEA PBM, which integrate a combined source-sink limitation of wood growth. The new calibrated model captured both the inter-annual and inter-site changes in stand wood growth that was observed across national environmental gradients. The model was also successfully evaluated against a meta-analysis of carbohydrate reserve pools in trees and satellite-derived leaf area index estimates. Our results indicated that the representation of the environmental control of sink activity does not affect the qualitative predictions of the future of the European forest productivity previously obtained from source-driven PBMs. However, the current, source-driven generation of PBMs probably underestimates the spatial heterogeneity of the effects of climate change on forest growth that arise from sink limitations.Further, we successfully used our findings regarding the dependences of annual wood growth at tree level (i.e., empirical rules of tree growth competition) to calibrate a module for the simulation of the individual growth of trees in the CASTANEA model. The coupled model was used to assess the potential effects of management on forest functioning and wood growth across France. We identified the areas where management efforts may be concentrated in order to mitigate near-future drought impact on national forest productivity. Around a quarter of the French temperate oak and beech forests are currently in zones of high vulnerability, where management could thus mitigate the influence of climate change on forest yield
Achard, Raphaël. "Etude du fonctionnement d'associations entre le bananier et une couverture vivante ; évaluation des potentialités et stratégies d'utilisation de plantes de service pour contrôler les adventices." Thesis, Université Paris-Saclay (ComUE), 2016. http://www.theses.fr/2016SACLA036/document.
Full textThe objective of this PhD thesis was to provide an approach to identify suitable cover crops (Pds) for weed control use in banana plantations. Firstly, we quantified the reciprocal effects between the banana crop and a grass cover controlled by mowing, for Brachiaria decumbens or Cynodon dactylon. These cover crops have had similar depressive effects on the nitrogen nutrition and on the productivity of the first cycle, but not afterward during the second cycle. Second step, we carried out a field characterization of eight legume cover crops, on isolated plants, under a range of light intensity. In non-limited light growth conditions, the biomass growth corresponded to an exponential dynamic, mathematically defined for each species by the biomass 14 days after sowing, and the relative growth rate (RGR). When affected by the shade, the RGR was reduced and the ratio between Leaf area and aerial plant biomass increased. We defined four adaptive strategies of the cover crops to the shade, what constitute criteria guidelines for cover crop use in banana cropping systems. For three of these species, on the basis of the response of the radiation use efficiency, we are proposing a plant growth model without any limiting factor other than light resource. In stands with the presence of weeds, neither of this cover crops was able to control the tall gramineous, but Stylosanthes guianensis and Centrosema pascuorum reduced the biomass of other weeds by 60%. Finally, in banana plantations, the two evaluated species provided a control of the weeds but reduced the productivity of the first cycle. Our results are comforting for the use of cover crops in banana plantation as a mean for weed control
Bedoussac, Laurent. "Analyse du fonctionnement des performances des associations blé dur-pois d'hiver et blé dur-féverole d'hiver pour la conception d'itinéraires techniques adaptés à différents objectifs de production en systèmes bas-intrants." Phd thesis, Toulouse, INPT, 2009. http://oatao.univ-toulouse.fr/7855/1/bedoussac.pdf.
Full textGomis, François. "Les nouveaux défis et enjeux de la politique étrangère de la France en Afrique francophone subsaharienne." Thesis, Paris 5, 2014. http://www.theses.fr/2014PA05D020.
Full textFrom 1960s to the end of the cold war, even beyond, the influence even the supremacy of France in the French-speaking territories in Sub-Saharan Africa is almost total. However, in this 21st century, the world competition in the research of new markets and the security of the energy supply leads inexorably the great powers to enter in “conflict of interests” by the mutual penetration of the “back-yards”. This is particularly true for France which has countries such as the United States, China, India, Brazil, Turkey, the Gulf Arab States, etc., to make a dramatic entrance in a geographical area where she judged it for a long time as her “exclusive domain” considering the historical, linguistic and political links. These new challenges and issues for the African policy of France are measured from now on, in the light of the transformations at work in the world with the globalization and the emergence of new powers of the South. The challenges and the issues are important for the external action of France and its place in the World, considering the fierce competition between new stakeholders and the ongoing African society changes. Nevertheless it still has economic, diplomatic and strategic assets which enable him to elaborate, thanks to the francophone cultural center, an original project, ambitious and promising. With this aim in mind, it will be necessary to answer to the two following questions: How to reform this traditional policy based on close and privileged relationships with African leaders without compromising, however, the comparative advantages of France on the spot? Which political strategy has to be implemented in order to identify the real common interests of the French and the French-speaking Africans, by taking into account the opportunities and threats, and to develop them in a mutually beneficial partnership?
Markgraf, Rudiger. "Abundance and growth of shrub and tree species in the balsam fir-yellow birch domain, under varying levels of landscape spatial heterogeneity." Mémoire, 2012. http://www.archipel.uqam.ca/5818/1/M12556.pdf.
Full textTeasdale, Valérie. "Établissement de couverts végétaux visant à inhiber la germination, la croissance et la survie de la Berce du Caucase (Heracleum mantegazzianum)." Thèse, 2017. http://hdl.handle.net/1866/19133.
Full textGiant Hogweed (Heracleum mantegazzianum) is an invasive species that causes human skin photodermatitis after contact with the sap. Control techniques of the plant often produced a soil devoid of vegetation cover, which facilitates reinvasion. The objective of my project was to evaluate the effect (competition) of plant seeding on the establishment of Giant Hogweed. First, I conducted a mesocosm experiment using five herbaceous plant mixtures in order to test the effect of composition and associated cover on germination, growth and survival of Giant Hogweed. Three mixtures, especially those with Solidago canadensis, reduced germination rate. Every mixture reduced growth and survival of Giant Hogweed seedlings. In order to identify the mechanism responsible for this phenomenon, I tested the effect of allelopathic substances, extracted from leaves and roots of S. canadensis, on germination of Giant Hogweed seeds. Although an allelopathic effect on a model species (radish) was detected, the substances did not impede Giant Hogweed germination. Considering germination occurs in darkness, a mechanism other than light or allelopathy would be responsible for the reduction of germination rate in certain plant mixtures. However, the reduction of light through plant cover would likely be the cause for the decrease of growth and survival of Giant Hogweed seedlings. A seed mixture mostly composed of grasses and rapidly producing a dense plant cover has a good potential for restoration following weeding.
Larose, Laurence. "Modélisation de la croissance architecturale et radiale du pin blanc dans l’est du Canada selon des facteurs environnementaux et climatiques." Thèse, 2018. http://hdl.handle.net/1866/21272.
Full textBilodeau-Gauthier, Simon. "Shoot and root responses of hybrid poplars to interspecific competition and soil fertility." Thèse, 2011. http://www.archipel.uqam.ca/4349/1/D2245.pdf.
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