Dissertations / Theses on the topic 'Carbone organique des sols'
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Follain, Stéphane. "Effet du réseau bocager sur l'organisation des sols. Redistributions des sols et stockage en carbone organique." Phd thesis, Agrocampus - Ecole nationale supérieure d'agronomie de rennes, 2005. http://tel.archives-ouvertes.fr/tel-00130432.
Full textLes objectifs de ce travail étaient de comprendre et de quantifier à l'échelle d'un paysage bocager, l'effet du système talus/haie sur l'organisation des sols et sur les stocks de carbone organique associés, ainsi que de décrire la dynamique des processus spatiaux qui ont conduit aux organisations observées.
Pour y parvenir, la démarche adoptée a combiné trois approches complémentaires. Tout d'abord, nous avons conduit une étude de terrain dans un paysage bocager historiquement documenté et offrant des conditions topo-paysagères contrastées avec pour but une caractérisation spatiale de l'effet du réseau bocager qui prenne en compte l'action de l'homme et la nature tridimensionnelle de la couverture pédologique à l'échelle du paysage.
Ensuite, nous avons couplé des approches de datation relative (analyse de documents historiques et géométrie des horizons) et absolue (carbone-14, césium-137), complémentaires des approches spatiales, pour dater les sols et analyser la dynamique des processus à l'origine des modifications de leur
organisation spatiale.
Cette prise en compte de la dimension temporelle était nécessaire pour améliorer notre compréhension des processus de redistribution en sol et nous permettre d'engager une modélisation spatiale et temporelle simulant des évolutions du paysage bocager en fonction de différents scénarii d'occupation des sols.
Follain, Stéphane. "Effet du résesau bocager sur l'organisation des sols. : Redistributions des sols et stockage en carbone organique." Rennes, Agrocampus Ouest, 2005. http://www.theses.fr/2005NSARD046.
Full textThe effect of hedgerow network on soil organisation at landscape scale is still unclear as most studies have been done in 2D focusing on situations with hedges perpendicular to the steepest slope. Therefore extrapolation at the whole landscape induces a wrong estimation of the hedgerow network effect at the landscape scale. Aims of this study were to understand and quantify at landscape scale, the effect of the hedgerwo network on soil organisation and on asociated soil organic carbon stocks and to desribe the dynamic of spatial processes responsible for these organisations. The adopted strategy has combined three complementary approaches. First a field study was carried out in an hedgerow network landscape historically documented, having contrated topographical and landscape situations. This in order to obtain a spatial caracterisation of hedgerow networks which take into account human activities and three dimensional nature of the pedological covre at landscape scale. We combined relative dating approaches (analysis of historical documents and of soil geometry) and absolute dating technique (14-carbon, 137-Caesium), complementary to the spatial approaches. These techniques allowed us to date the organo-mineral horizons of the soil cover and to analyse the dynamic of processes responsible for modifications of the soil spatial organisation
Follain, Stéphane. "Effet du réseau bocager sur l'organisation des sols : redistributions des sols et stockage en carbone organique /." Rennes : Éd. de Géosciences Rennes, 2006. http://catalogue.bnf.fr/ark:/12148/cb401902122.
Full textContient aussi un texte en anglais. Bibliogr. p. 217-228. Résumé en français et en anglais.
Doupoux, Cédric. "Caractérisation et modélisation de la dynamique des stocks de matière organique profonde des sols amazoniens." Thesis, Toulon, 2017. http://www.theses.fr/2017TOUL0003/document.
Full textRecent results have shown that equatorial podzols store large amounts of carbon in their deep Bh horizons. This leads to two main questions: (1) how and at what kinetics these soils were formed, (2) how climate change could induce atmospheric carbon production that could impact the global climate system.In this context, we have developed a model that allows to constrain carbon fluxes both by the observed C stocks and their 14C age. In a sufficiently simplified situation, we have established a formal relationship between the C stock evolution and its 14C age. Applied to Amazonian podzols, our model has brought new and unexpected results. It has been shown that the surface horizons of the most hydromorphic podzolized areas are the largest contributors of MOD transferred to the hydrographic network then to the sea. It is observed that the formation of Bh is only possible by considering two compartments, fast and slow. The estimate of their formation time (low estimate) allowed to differentiate between relatively young podzols (formation time 15 – 25 ky) developed on relatively recent Holocene sediments and old podzols (formation 180 – 290 ky) developed on older sediments. The carbon accumulation rate in the studied podzols ranges from 0.54 to 3.17 gC m-2 y-1, which corresponds to a carbon sequestration around 3 1011 gC an-1, which is significant at the geological scales.Column percolation experiments allowed us to show the reactivity of the Bh material and the presence, despite very high C/N ratios (63 on average), of a significant bacterial activity which modifies the nature of the MOD which percolates through it. This MOD has the capacity to transport Al and Fe in the form of complex organometallic complexes capable of migrating through very kaolinitic materials. These results contribute to the understanding of the transfers of pedologically formed MOD in the deep aquifers.Under the hypothesis of the appearance of a climate with contrasting seasons, we have been able to show that a 90-day period without rain after the disappearance of the perched water-table would not allow to reach the point of entry of air by drying of superficial horizons. Nevertheless, assuming an air entry, the extrapolation of the experimentally measured mineralization rates under oxic conditions results in a production of atmospheric C around 2.0 1014 g of CO2 per year, which may involve a positive feedback from the global climate system
Rogeon, Hervé. "Influence de la gestion des sols sur la structure et la dynamique du carbone organique." Poitiers, 2010. http://theses.edel.univ-poitiers.fr/theses/2010/Rogeon-Herve/2010-Rogeon-Herve-These.pdf.
Full textCarbon dioxide sequestration in plant and carbon storage in soil and biomass could be considered as a complementary solution against the increase in concentration of gases responsible for climate change. The aim of this work is to understand the mechanisms of organic matter stabilization in the deepest horizons of soils. The influence of landuse, minerals and amendment with organic matter (compost) on the carbon dynamic has been studied. Four soils representing different landuses (grassland, forest and arable soil) were characterized. The organic matter decreases in amount with depth and becomes more refractory. The relatively high amount of organic matter in deep horizons is probably related to the strong presence of clays and to the low biological activity. The different vegetations seem to influence strongly the quantity of soil organic carbon while affecting slightly its quality. Indeed, the structural study of organic matter shows weak differences whereas the amount of carbon and lipids are more important in arable soil. The study of organomineral associations revealed that the bacterial contribution is more important in fine fractions. Amendment with organic matter of an arable soil affects the biological activity and improves its structural stability. The distribution of the different forms of organic matter has been modified and the presence of molecules originating from the compost in lipids and humic substances show an incorporation of exogenous carbon
Cardinael, Rémi. "Stockage de carbone et dynamique des matières organiques des sols en agroforesterie sous climat méditerranéen et tempéré." Thesis, Université Paris-Saclay (ComUE), 2015. http://www.theses.fr/2015SACLA003/document.
Full textAgroforestry is a land use type where trees are associated with crops and/or animals within the same field. This agroecosystem could help mitigating climate change, and also contribute to its adaptation. The goal of this thesis was to evaluate the potential of soil organic carbon storage under agroforestry systems. This study was performped at the oldest experimental site in France, a trial supervised by INRA since 1995, but also at farmers' fields. Soil organic carbon stocks were compared between agroforestry and agricultural plots, down to 2 m soil depth. All organic inputs to the soil were quantified (tree roots, leaf litter, crop roots and residues). The stability of additionnal stored carbon was caracterised with soil organic matter fractionation, and soil incubations. A model of soil organic carbon dynamic was described in order to better undrestand this dynamic in agroforestry, especially in deep soil layers. This study revealed the interest and the potential of agroforestry systems in increasing soil organic carbon stocks, with accumulation rates of 0.09 to 0.46 t C ha -1 yr -1. It also reveals the role of tree rows in this storage, and the importance of carbon inputs from root mortality. However, it raises concerns about the stability of this storage
Cambou, Aurélie. "Evaluation du stock et de la stabilité du carbone organique dans les sols urbains." Thesis, Rennes, Agrocampus Ouest, 2018. http://www.theses.fr/2018NSARD086/document.
Full textSoils are the largest terrestrial pool oforganic carbon and thus play a key role in mitigatingclimate change. The urban soils account for 3% of theworld’s territory and urbanization is currently theprimary cause of land use change. The increase ofartificial areas have led to a growing interest in theurban soil ability to store organic carbon. This workaimed to understand the contribution of urban soils tothe global organic carbon stock and to propose astandardized method for its monitoring. The researchalso focused on studying the stability of organic carbonin urban soils and modeling its dynamics. A databasewas built using data available at the French territorylevel as well as using additional measurements acquired in three French cities.The organic carbon stock in urban open soils aresimilar between cities, and equivalent, or even higherin depth, than that of surrounding forest soils. Thestock in open soils is particularly dependent upon themanagement methods of the urban green spaces,and on the specific site history. Thus, open urban soilsare characterized by a high proportion of labileorganic matter at 0-44 cm depth. Conversely, sealedsoils have very low carbon stocks. They arecharacterized by a high proportion of stable organicmatter whose evolution (storage or mineralization)depends on the dormant state of the microbialcommunities. A conceptual model of carbon dynamicsfor these two soil types has been developed. Finally,recommendations for optimizing carbon monitoringand urban soil management have been proposed
Lefèvre, Romain. "Matière organique stable du sol : dynamique et mécanismes de (dé)stabilisation." Thesis, Paris 6, 2015. http://www.theses.fr/2015PA066261/document.
Full textTo understand the fate of stable soil organic carbon (SOC) in a warmer world is a major challenge to be able to predict future atmospheric CO2 concentrations. To do so, it is of prime importance to understand what the stable SOC is exactly and how its mineralization rate is modulated by temperature. This thesis proposed to study (1) the temperature sensitivity of stable SOC mineralization; (2) the response of soil microbial communities to temperature and (3) to establish a link between SOC decomposability and its age. Soil samples from four long term bare fallow experiments were used for work. We incubated soils sampled at the beggining of each experiment and after several decades of bare fallow at different temperatures for 427 days and we regularly monitored soil respiration. At the end of the incubation, soil microbial communities were assessed using pyrosequencing techniques. Finally, we determined the age of soil organic carbon by radiocarbon dating in soil samples from the chrono-sequence located at Versailles, France. The results obtained brought evidence for a general relationship between the mineralization rate of soil organic carbon and its temperature sensitivity. We also found that microbial communities linked to stable organic carbon are more diverse but also more sensitive to a temperature increase. Some bacterial phyla were particularly impacted by the temperature increase and the organic resource rarefaction. Finally, this thesis highlighted the difficulties met with the radiocarbon dating technique
Gobé, Valérie. "Matière organique complexe du sol ; structure et rôle dans les processus d'humification du carbone xénobiotique." Poitiers, 1998. http://www.theses.fr/1998POIT2316.
Full textTiruta-Barna, Ligia. "Thermodynamique des mélanges compose organique - solvant supercritique : application a la décontamination des sols pollués." Lyon, INSA, 1995. http://www.theses.fr/1995ISAL0109.
Full textCarbon dioxide super critical extraction is applied to the remediation of soils contaminated by organic compounds. We have studied three aspects of the extraction process: 1) The calculation of solubility of organic compounds in super critical fluids. W e proposed a thermodynamic model which is based on the relations existing between the Helmholtz energy of pure components and the excess Helmholtz energy in a mixing process at constant packing fraction. The components may intervene in the equation of state of the mixture with varied equations of state. This model was applied to solid-fluid and liquid-fluid equilibria. A group contribution method was developed for hydrocarbon-carbon dioxide mixtures. 2) The adsorption equilibrium of biphenyl in soil in the presence of super critical carbon dioxide was studied experimentally and represented with the Bragg Williams lattice model. The adapted model allows adsorption calculation for a given set of temperature-pressure-fluid composition 3) For the kinetic study of the extraction, we used a soil artificially contaminated with biphenyl. In the soil, the pollutant is distributed between a precipitated phase and an adsorbed phase. Thus, the extraction model contains a dissolution kinetic term and a desorption kinetic term. The model parameters (the dissolution rate coefficient, the overall mass transfer coefficient between soil particles and the fluid and the fraction of precipitated biphenyl from the total quantity in soil) was estimated by fitting with experimental extraction data
Bortoluzzi, Edson Campanhola. "Nature des constituants, propriétés chimiques et physiques des sols : modélisation des charges superficielles dans des sols sableux au Sud du Brésil." Paris, Institut national d'agronomie de Paris Grignon, 2003. http://www.theses.fr/2003INAP0003.
Full textPeltre, Clément. "Potentialité de stockage de carbone dans les sols par apport de matières organiques exogènes." Phd thesis, AgroParisTech, 2010. http://pastel.archives-ouvertes.fr/pastel-00602825.
Full textL'étude de la composition chimique de la fraction dite soluble du fractionnement biochimique Van Soest a révélé que la nature chimique de cette fraction de MO change lors du traitement par compostage des MOEs: elle est très riche en polysaccharides en début de compostage et s'enrichit en MO riche en composés azotés stabilisés au cours du compostage.
Le potentiel d'utilisation de la spectroscopie proche infra-rouge (SPIR) pour caractériser les MOEs et leur devenir dans le sol a été étudié. Des prédictions satisfaisantes ont été obtenues pour les teneurs en C et N des MOEs ainsi que pour les fractions biochimiques Van Soest des MOEs. L'indicateur de stabilité de la MO (ISMO), estimateur de la fraction résiduelle de la MO des MOEs à long terme dans les sols, a été prédit de manière satisfaisante.
La potentialité de stockage de C à long terme dans un sol soumis à des apports répétés de MOEs a été étudiée en utilisant des résultats de 4 essais au champ de moyenne et longue durées. les apports répétés de MOEs ont entrainé des augmentations significatives des stocks de C dans les sols qui ont pu être reproduites de façon satisfaisante avec le modèle RothC qui a été ainsi paramétrés pour pouvoir simuler des apports de MOEs de types divers.
L'étude des changements dans la composition de la MOS suite à ces apports répétés de MOEs dans l'essai Qualiagro a révélé une modification préférentielle de la fraction de MOS particulaire de taille > 50 µm, en particulier par un enrichissement en lignine. La composition de la fraction de taille 0-50 µm est également modifiée mais dans une moindre mesure et de façon moins directement liée à la composition des MOEs apportées.
Sallih, Zaher. "Relations entre activité rhizosphérique et décomposition de la matière organique des sols au niveau de la biomasse microbienne et de la minéralisation du carbone et de l'azote." Montpellier 2, 1990. http://www.theses.fr/1990MON20138.
Full textPayandi-Rolland, Dahédrey. "Biogéochimie du carbone organique dans les eaux de tourbières à pergélisols : une approche expérimentale." Thesis, Toulouse 3, 2020. http://www.theses.fr/2020TOU30266.
Full textThe anthropogenic emissions of carbon dioxide (CO2) into the atmosphere are held responsible for the current global warming experienced by the Earth. Given the amplified effect of warming in the northern regions, the main objective of this thesis is to assess the factors that could influence the organic matter (OM) degradation within a carbon-rich permafrost peatland. For this purpose, we studied the effect of biological and geochemical parameters, which are directly or indirectly influenced by climate change, on the degradation of OM. Field studies and experiments were carried out in discontinuous permafrost areas of Eastern Siberia and Sweden, along with laboratory experiments using substrates from these regions and from peatlands of NE Europe. Experiments were conducted as a function of temperature, bacterial biomass, OM origins, water bodies heterogeneity, vegetation type, freezing and thawing cycles, anoxic conditions and soil depths. The originality of this work consists in the combination of various (bio)geochemical analyses using both fieldwork and laboratory approaches linking the different systems controlling OM degradation in the natural environment (mainly microbiology and geochemistry). After an introduction dealing with possible positive feedback of OM degradation in northern peatlands on climate warming, the first chapter is dedicated to a general context giving an insight of the OM in the arctic region under climate change challenges and presenting all the techniques, analyses and methods employed for this thesis. The second chapter describes the three studied sites and the general fieldwork, which involved the study of OM behaviour during diel cycles. The third chapter tackles the origin of OM and the water bodies heterogeneity effect on the biodegradation of OM. The fourth chapter investigates the impact of freeze-thaw cycles of peatland water bodies on OM degradation during transitional periods, such as early spring and late autumn. Finally, the last chapter reports the result of aerobic and anaerobic experiments. The aerobic experiment tests the effect of temperature and heterotrophic bacteria on biodegradation, while the anaerobic experiment deals with the potential production of greenhouse gases from a soil profile collected in a peatland. The main results of this thesis highlight that i) during the night, small thermokarst lakes release up to three times more CO2 compared to day-time, and big lakes become a source of CO2 rather than a sink; ii) along a hydrological continuum, from supra-permafrost water to rivers through thermokarst lakes, the degradation rate of OM decreases and the biodegradability of waters increases; iii) recurrent freeze-thaw cycles during early spring and late autumn do not influence the degradation of carbon but favor the OM-metals complexes in neutral pH waters of large lakes and rivers; iv) temperatures during these transitional periods (4 °C) exhibit the same effect on biodegradation than the summer temperatures (25 °C); and v) when frozen peat thaws, it does not release a significantly different amount of CH4 and CO2 from biodegradation processes compared to the active layer. The studies carried out in this work bring an overview of the various direct and/or indirect effects of climate change on the OM transformation by biotic and abiotic factors in a discontinuous permafrost area. Furthermore, the study of carbon behaviour in wetlands soils and waters, as well as CO2 and CH4 emissions, may help to determine the influence of climate change on the interactions of biodegraded carbon from pedo- and hydrosphere with the atmosphere
Jolivet, Claudy. "Le carbone organique des sols des Landes de Gascogne : variabilité spatiale et effets des pratiques sylvicoles et agricoles." Dijon, 2000. http://www.theses.fr/2000DIJOS064.
Full textLutfalla, Suzanne. "Persistance à long terme des matières organiques dans les sols : caractérisation chimique et contrôle minéralogique." Thesis, Université Paris-Saclay (ComUE), 2015. http://www.theses.fr/2015SACLA008/document.
Full textSoils store three times more carbon than the atmosphere, under the form of a complex mixture of molecules called soil organic matter (SOM). Some of these molecules have been standing in the soil for hundreds to thousands of years. Three main mechanisms are invoked to explain this long term carbon persistence in soils, (i) chemical recalcitrance, (ii) physical protection in aggregates and (iii) protection by adsorption on mineral surfaces. One of the major challenges in SOM science is to better understand the relative importance of each mechanism, that is the aim of this PhD project. Here, we use samples from by long term bare fallows (5 sites across Europe). These experimental plots have been kept free of vegetation by manual or chemical weeding for several decades and have been regularly sampled and stored. As the duration of the bare fallow increases, biodegradation occurs and samples get enriched in persistent carbon.First experiments consisted in testing the efficiency of chemical oxidations (two reagent were tested, sodium hypochlorite –NaOCl- and hydrogen peroxide –H2O2) on the longest bare fallow. We concluded that oxidation methods were not able to efficiently isolate a pool of persistent carbon at the centennial timescale. In terms of mechanisms of persistence, the obtained results show that chemical recalcitrance does not seem to be the major mechanism. Indeed, over the duration of the bare fallow, the chemical composition of SOM, as seen by synchrotron based NEXAFS spectroscopy, shows little changes. There is a consistent increase in carboxylics for all sites (12% increase on average) though it is significant for 2 out of the 4 selected sites. We also studied the particular persistence of soil pyrogenic carbon, which is thought to be at least five times more persistent than bulk SOM. Results show that pyrogenic carbon lacks long term persistence. Indeed the BPCA-estimated mean residence time of pyrogenic carbon (116 years) is on average 1.6 times longer than MRT for bulk SOM (73 years). Finally, the study of mineralogical control of the persistence of SOC showed that clay minerals containing potassium (illite) seemed to protect less carbon. As seen by NEXAFS-STXM, more mineral surfaces with very little SOM appear with the duration of bare fallow. C:N ratio decreased in all clay fractions, suggesting a preferential persistence of N-rich compounds. Presence of microaggregates in the coarser clay fraction led to the coexistence of two protection mechanisms: adsorption and physical protection
Naisse, Christophe. "Potentiel de séquestration de carbone des biochars et hydrochars, et impact après plusieurs siècles sur le fonctionnement du sol." Thesis, Paris 6, 2014. http://www.theses.fr/2014PA066518/document.
Full textBiochars and hydrochars production can form amendments enriched in aromatic carbon, potentially recalcitrant against microbial degradation, while massively producing renewable energy. These amendments are aimed to increase soil organic matter (SOM) quantity, and soil fertility. However, due to the diversity of their feedstock and production processes, misunderstandings exist on the potential of these materials to store C in soil at short and long term. In addition, methods to rapidly evaluate the long-term stability of these materials remain to be developed, in order to allow users to determine the quality of these new amendments. This work was consisted for assessing the stability of biochar and hydrochars, biologically by soil incubations, and chemically by oxidation with acid dichromate. The biochar showed a high level of biological and chemical stability, allowing to storage a large amount of carbon throughout the century. In opposite, the hydrochars might not allow sequestering massively carbon beyond the decade, due to its lower biological and chemical stability. The hydrochars induced a positive priming effect (stimulation) while biochar induced a negative priming effect (protection). Physical weathering of both materials led to an increase of stability and a decrease of the priming effect, highlighting the importance of environmental factors in evaluation of strategies for sequestering carbon. Charcoal kiln soils were used as a model for long-term study of the input of biochar in soil after several centuries. Their analysis showed that the contribution of biochar sustainably improves the physicochemical properties of the soil, such as clay content, cation exchange capacity (CEC), amount of nitrogen, phosphorus, and soluble carbon. However, after several centuries of biochar amendment, microbial communities showed no specific adaptation to the degradation of a new biochar input. In this soil model, the input of plant residues resulted in a negative priming effect. Thus, the contribution of biochar in generating specific conditions, allows the maintenance of microbial communities with the ability to switch of substrates, for a new source of substrates more easily degradable. Further works are needed to assess the stability of biochar in soil-plant system
Lavaud, Aurélien. "Extraction et caractérisation de la matière organique soluble des horizons profonds d'un sol arable." Poitiers, 2010. http://theses.edel.univ-poitiers.fr/theses/2010/Lavaud-Aurelien/2010-Lavaud-Aurelien-These.pdf.
Full textThe increase in the atmospheric CO2 concentration due to the combustion of the fossil resources and deforestation is the major environmental problems today. To store carbon and thus to decrease the concentration of CO2 emitted by human activity in the atmosphere, it would be necessary to be able to operate the carbon sinks located in the continental biosphere. The largest carbon surface reservoir of the continental biosphere is the soil, which stores 1500 Mt carbon. The potential of French soil to store carbon is currently being evaluated for the plowed horizon, i. E the first 30 cm. However, recent studies showed that a significant proportion of soil carbon is stored in horizons B and C. The precise role of soluble organic carbon or DOC (Dissolved Organic Carbon) in the stabilization and / or destabilization of carbon deep horizons is indispensable to adapt the methods of land management and cropping systems to increase the stock of carbon in soils. Despite abundant literature, studies on DOC are mainly limited to soils of forest ecosystems and especially in laboratory scale. The results were never confirmed on the ground. The overall objective of this thesis is to better define the proportion of soluble organic matter of different horizons of arable soil and indicate their main structural features. This work takes into account the importance of the mode of cultural practice and the impact of prolonged drought particularly in deep horizons. Different analytical techniques (spectrofluorimetry, chromatography size exclusion, pyrolysis GC / MS, 13C NMR) were used on waters collected at the lysimeter plates and porous candles but also HPO, TPH and HPI extracts, for characterizing the OM of deep horizons, while being based on existing work on surface water. The work showed that the OM of the deep horizons was characterized by low aromaticity, a lower molecular weight and by the presence of compound lignins types and terpenoids
Phan, Ha Hai An. "Transfert d’eau et de matière sur un petit bassin versant agricole du Nord Vietnam : suivis à l’échelle pluriannuelle et à l’échelle de la crue." Paris 6, 2009. http://www.theses.fr/2009PA066718.
Full textQuibel, Edouard. "Impacts de la préparation du sol lors de la phase de plantation sur la dynamique des matières organiques et la fonction de stockage du Carbone dans les sols forestiers Impact du travail du sol localisé sur le stock de carbone organique du sol et la communauté microbienne en condition de plantation en forêt tempérée Changes in soil organic carbon stock by mechanical site preparation in oak and pine plantations on an acidic soil Impact du travail du sol localisé sur le stock de carbone organique du sol et la communauté microbienne en condition de plantation sur sol à engorgement temporaire en eau." Thesis, Normandie, 2020. http://www.theses.fr/2020NORMR017.
Full textIn the current context of climate change, forests are seen as a carbon sinj, i. e. they can contribute to C storage. This storage can take place in the medium term in woody biomass and in the longer term in soils. In order to preserve forests and their C storage capacity, foresters have to carry out artificial regeneration (i. e. planting) to adapt stands to future conditions. To ensure the success of this planting stage, it is sometimes necessary to remove some constraints such as the presence of blocking vegetation, compaction or waterlogging of soil. To do this, a Mechanical Soil Preparation (MSP) can be carried out prior to plantin. This PMS work may cause a Soil Organic Carbon (SOC) loss by mineralization. In order to limit the negative effects of PMS, tools have been developed to prepare the soil only in a localized area, on the future line of plants. These tools have been developed to respond to some situations. The Reversible Scarifier® (RS) tool and the Multifunction Subsoiler (MFSS) are designed to prepare soils compacted and/or invaded by eagle fern (Pteridium aquilinum). The Razherb® (RAZ) and the Culti 3B® (C3B) tools are designed to prepare compacted and/or waterlogged soils invaded by Molinia caerulea (Molinia caerulea). First, based on 6 sites belonging to the ALTER network, the impact of the RS tool alone and in combination with MFSS on COS was evaluated 5 years after the PMS. This evaluation therefore focused on the quantity and quality of SOC. The impact of the tools on the microbial functioning of the soil was also tested. This part showed a decrease in the stock of C and mineralized C by the microbial community under controlled conditions localized to the prepared area but impacts at the forest stand scale depend on soil characteristics. Second, based on 3 sites belonging to the PILOTE network, the impact of the combination of RAZ+C3B tools on SOC stocks and potential mineralization was evaluated. On these soils with temporary waterlogging, adecrease in SOC stock was observed in the prepared area only in the topsoil (0-30 cm). On the other hand, both SOC stock on the full profile and the potential mineralization did not have a significant effect on the prepared area. At the forest stand scale, the RAZ+C3B combination had no effect on SOC stock or potential mineralization. This thesis work suggests that although they had an impact on the prepared area, the tools used in this study had low influence on the soil at the forest plot scale. However, these observations may vary according to the soil type and have a significant impact on the forest plot
Soto, Gerardo. "Statut organique des sols en milieu aride : étude de la région de Coquimbo (Chili)." Phd thesis, Université d'Orléans, 2009. http://tel.archives-ouvertes.fr/tel-00444588.
Full textGauthier, Anthony. "Production et devenir des matières organiques dissoutes dans les hydrosystèmes faiblement anthropisés." Phd thesis, Université de Bourgogne, 2009. http://tel.archives-ouvertes.fr/tel-00450229.
Full textQuilici, Laeticia. "Le carbone organique dans les mâchefers d'incinération d'ordures ménagères : extraction, structures et rôle sur l'environnement." Toulon, 2001. http://www.theses.fr/2001TOUL0010.
Full textLn France, about 50 % of municipal solid wastes are incinerated (with or without energy recuperation). The main solid residue from incineration process is bottom ash. Municipal Solid Waste Incineration (MSWI) bottom ash storage or valorisation poses an ecological and economic problem for industrials and local communities. This study is about characterisation of organic fraction present in MSWI bottom ash as well as its influence in short and long term behaviour of bottom ash. Differentia] Scanning Calorimetry (DSC) is applied to speciation and evaluation of carbon in MSWI residues. This innovative recognition approach highlights and quantifies different types of carboned materials in bottom ash: Labile Organic Carbon (LOG) and Refractory Carbon (RC). Characterisation and dosage of organic compounds (paraffins, carboxylic acids, polycyclic aromatic hydrocarbons) are realised with various extraction (traditional extraction (Soxhlet) and Supercritical Fluid Extraction (SFE)) and identification (Gas Chromatography coupled with mass spectrometer detector (GC-MSD)) methods. This fine characterisation of organic matter has permitted to evaluate the short and long term available and mobilisable organic reservoir, and also the complexation possibility of some metals with carboxylic acids generously present in bottom ash. Moreover, any ecotoxicity tests performed on studied residues gets a new approach of bottom ash characterisation. A direct correlation with bottom ash physico-chemical parameters (usually studied) and its biotests responses is not possible. In opposite, a relation with carboxylic acids content and ecotoxic indice bottom ash is highlight
Tete, Kwami Emmanuel. "Dynamique intra-annuelle de la minéralisation du carbone organique dans les sols minéraux hydromorphes et à l’échelle du versant agricole." Rennes, Agrocampus Ouest, 2014. http://www.theses.fr/2014NSARD075.
Full textGlobal warming is expected to affect soil water regime and their impact on soil organic matter dynamics. Hydromorphic minerals soils characterized by the alternation of water saturation and non-saturation conditions are the places of specific biogeochemical processes, regimes of carbon supply and they play an important role in carbon sequestration. However, very few studies have addressed the dynamics of organic carbon (C) mineralization in these soils and the role of water regime. The general objective of the thesis is to characterize the effects of hydromorphic soil water regime on the dynamics of C mineralization to the intra-annual scale and in an agricultural context. The studied site is an agricultural hillslope which is one of the sites of Environment research Observatory (ORE AgrHys) located in the Kerrolland locality (Naizin, France). It presents a juxtaposition of poorly-drained hydromorphic area and well-drained area, with different soil water regimes. The effects of the durations of saturation and transient saturation conditions (alternation of saturation and non-saturation conditions), characteristics of hydromorphic minerals soils, on C dynamics (dynamics of mineralization rate, dynamics of CO2 emissions, organic and inorganic dissolved dynamics and coupled nitrogen dynamics) were evaluated through incubation experiments. Furthermore, in-situ measurements of soil CO2 effluxes during one year, were performed in order to characterize the effects of soil drainage and hydromorphic gradient on the spatio-temporal variability of C mineralization across the studied hillslope. In incubation conditions, C mineralization in saturation conditions was two times lower than non-saturation conditions. In saturations conditions, C mineralization dynamics was unaffected by the durations of saturation, contrary to the dynamics of C mineralization during desaturation. Saturation conditions favored production and accumulation of labile organic compounds whose rapid mineralization during desaturation resulted in flush of CO2 emissions. Therefore, more the duration of previous saturation conditions is long more the C mineralization rate during desaturation is high. Transient saturation conditions resulted in an increase in the total amount of C mineralized, that reached the same orders of magnitude than that of soils maintained in non-saturation conditions. In-situ, depending on the season, well-drained soil CO2 effluxes were two to five times higher than that of hydromorphic minerals soils. At annual-scale, the soil water regime of hydromorphic minerals soils induced 37 to 41% reduction in CO2–C emissions compared with well-drained soils. This study contributes to understand the role of soil water regime in the dynamics of C mineralization in hydromorphic minerals soils. These results may be used to identify the role of hydromorphic soils
Fujisaki, Kenji. "Devenir des stocks de carbone organique des sols après déforestation et mise en culture : une analyse diachronique en contexte amazonien." Thesis, Montpellier, SupAgro, 2014. http://www.theses.fr/2014NSAM0036/document.
Full textSoil organic carbon is a key component of soil quality, and represents a large part of the terrestrial carbon stock, sensitive to human perturbations including land-use change. In Amazonia, deforestation induces greenhouse gases (GHG) emissions due to vegetation burning, but SOC stocks also change, which can induce GHG emissions. We show that these changes are misunderstood at the biome scale, because of the chronosequence approach that induces uncertainties, and because of the lack of management data of the agrosystems established after deforestation. We studied here an agronomic trial with a diachronic approach in French Guiana, deforested with a fire-free method that returned large amount of forest organic matter. Three agrosystems were set up: a grassland and two annual crop systems (maize/soybean) with and without soil tillage. We aimed to measure the fate of forest carbon and of SOC in the agrosystems. SOC stocks fluctuations were assessed up to 5 years after deforestation in the layer 0-30 cm, and a comparison forest-agroecosystems in the layer 0-100 cm was done at 5 years. Decomposition of woody debris buried in the soil after deforestation was assessed by mass loss approach and Rock-Eval pyrolysis. SOC distribution in granulometric fractions was measured 4 years after deforestation. δ13C methods were used in the grassland soil to distinguish the carbon derived from forest or grassland. We found that carbon inputs from deforestation increased SOC stocks, but only at short-term because woody debris decomposition was fast and did not induce a mid-term SOC storage. Five years after deforestation SOC stocks in grassland are similar to the forest, thanks to carbon inputs from root activity. In the annual crops SOC stocks decrease of about 18 %, and no difference is found according to the soil tillage. The decay of forest soil carbon, which affected the whole granulometric fractions of SOC, is thus offset in grassland but not in annual crops. RothC model could be validated in our study, but slightly overestimated SOC stocks in annual crops. Replaced in the Amazonian context, our results showed that the SOC decrease here was lower than other studies across humid tropics. This can probably be explained by the optimal management of the agrosystems, and the short time lapse studied
Juarez, Sabrina. "Régulations biotiques et abiotiques de la décomposition des matières organiques des sols." Phd thesis, AgroParisTech, 2013. http://pastel.archives-ouvertes.fr/pastel-01049725.
Full textKeraval, Benoît. "Les métabolismes oxydatifs extracellulaires : une nouvelle vision des processus de minéralisation du carbone organique du sol." Thesis, Clermont-Ferrand 2, 2016. http://www.theses.fr/2016CLF22740/document.
Full textHellequin, Eve. "Effets des biostimulants sur le fonctionnement biologique de sols d’agrosystèmes : réponses des communautés microbiennes et dynamique de minéralisation du carbone organique." Thesis, Rennes 1, 2019. http://www.theses.fr/2019REN1B029.
Full textModern agriculture is undergoing important changes toward agroecological practices that rely on biodiversity and ecological processes. In agrosystems, the organic matter is the key of the soil fertility and an important reserve of carbon. Organic fertilization by crop residues is therefore an agricultural practice that improve the organic matter content in soil. Soil microorganisms have an important role in the organic carbon (orgC) dynamic because they are key players of its mineralization and are involved in the nutrients recycling. Thus, the use of agricultural biostimulant (BS) intended to enhance this microbial function is proposed as an alternative solution to improve indirectly plant growth while reducing chemical inputs. This thesis aimed to i) identify the effect of soil biostimulant on heterotrophic microbial communities, the orgC mineralization and the nutrient releases, ii) evaluate its genericity by testing different experimental conditions and iii) identify the environmental filters that control both the microbial communities and the mineralization function. We showed that the orgC dynamic was different according to contrasted physico-chemical and biological characteristics of different soils. We showed that plants can also influence the orgC dynamic by returning litter to the soil and through its root effect on the bacterial and fungal communities. Unlike plants, the amount of orgC provided by the two tested BS was negligible. However, we evaluated the effect of one BS as at least similar or even higher than those of plant on active bacterial and fungal abundances, richness and diversity. Among the two BS tested we showed that one enhanced the orgC mineralization by recruiting indigenous soil bacterial and fungal decomposers and that the other did not affect the orgC mineralization but activated indigenous soil plant-growth-promoting bacteria as well as soil bacterial and fungal decomposers. Furthermore, our study call for new normative methodological and systemic approach by monitoring simultaneously several descriptors for advancing our knowledge on BS action on microbial soil functioning
Scheiner, Javier David Revel Jean-Claude Guiresse Agnès Maritchù. "Spéciation du carbone, de l'azote et du phosphore de différentes boues de stations d'épuration au cours de leurs incubations contrölées dans deux types de sol." Toulouse : INP Toulouse, 2008. http://ethesis.inp-toulouse.fr/archive/00000379.
Full textPaul, Alexia. "Dynamique couplée de l’hydrogène et du carbone organiques des sols : approches par isotopes stables pour la prévision du devenir du 3H, 2H, 13C et 14C." Thesis, Aix-Marseille, 2017. http://www.theses.fr/2017AIXM0068/document.
Full textRadiocarbon (14C) and tritium (3H) are naturally released into the environment but also through nuclear activities. The releases are expected to persist for the next decades, it is important to predict their fate and their residence time in soils. The objective of this thesis is to propose a quantitative prediction and a simple modeling of the fate of 14C and 3H in soil organic matter (SOM). The originality of this work is twofold: first, we hypothesize that the incorporation and fate of NEH atoms in the soil are coupled to the carbon dynamics. Second, we chose to trace carbon and hydrogen by natural or artificial 13C and 2H tracing.Through natural in situ 13C tracing, we quantified the carbon recently incorporated by vegetation in few decades. Deep horizons contain a large part of this carbon (typically 20 to 30%). We adapted the RothC model to the deep soil C dynamics. This allowed us to predict that 10% of C will persist for several centuries in the deeper layers. The labelling experiments showed that the microbial activity is driving the incorporation of hydrogen from water into SOM, and allowed us to establish the CH stoichiometry of biotransformations. These experiments were a mean to propose a model of the coupled C and H dynamics of the SOM in the short and medium term (decades). The results of this thesis contribute as well to the improvement of the interpretation of natural abundances in 13C and 2H stable isotopes. A meta-analysis of the correlations between the 13C and 14C concentrations of global soils has demonstrated that the 13C enrichment of deep organic matter can be fully explained by the 13C/12C ratio of the vegetation from which they are derived
Moni, Christophe. "Stabilisation physique et physico-chimique de la matière organique dans les horizons profonds du sol." Paris 6, 2008. http://www.theses.fr/2008PA066196.
Full textVenkatapen, Corinne. "Étude des déterminants géographiques et spatialisation des stocks de carbone des sols de la Martinique." Thesis, Antilles-Guyane, 2012. http://www.theses.fr/2012AGUY0513/document.
Full textSoils elements stocks, and particularly those of carbon, are in constant evolution under natural factors effect (climate, vegetation, clays content, etc) and anthropic factors effect (soils uses, etc). Our objective is thus, (i) to better understand the relations between soil, farming system and stored carbon quantity, (ii) to study the consequences of soils uses changes and of soils managements changes on organic matter shapes in soil and (iii) to specify organic matter role on soil properties physics.Representative agri-pedological situations of the three great mineralogical models of tropical soils (allophonic soils (not crystallized clays), 1:1 clay soils and 2:1 clay soils) and presenting agricultural systems of various levels of intensification (intensive monocultures intended for export, slightly intensified farming systems, etc) were thus selected in the soils of Martinique. In addition, to limit the effects of their former uses, we generally chose to the minimum 3 years old farming situations.The analysis of the various lands carbon stocks reveals different behaviors: in allophonic soils, a correlation exists between carbon content (or organic stock) and texture (or fine elements content), as well for not cultivated as for cultivated situations. Variations ranges (reduction) of carbon stocks observed under various management soils systems effect, also depends on texture: in sandy soils, carbon sequestration potentiality is low or null, on the other hand, carbon storage potentialities are higher in clay soils.The estimation of total carbon stocks on the scale of Martinique, for one meter of depth and for and average situation between the use soils charts of 1969/70 and 1979/80, rises to 11,859 Mt of C calculated for 95,8% of the surface.Soil organic matter distribution varies with soil texture: in sandy soils, with low contents of organic matter, organics matters are mainly associated with the sandy fractions; in clay soils, richer in organic matters, 50 to 60% of the organic matters are associated with the argillaceous fraction. In the same way, the organic matter dynamics also depends on soil texture: in sandy soils, organic stocks variations are primarily due to carbon loss or accumulation of the sandy fraction; in clay soils, the argillaceous fraction takes part in a dominating way in organic stocks variations of these soils at the time of their setting in culture or meadow; the sand-clay soils have an intermediate behavior between these two poles.Structural stability varies with mineralogy. Andosols (or ALL) present a high degree of aggregation and stability, due to the presence of allophones and their particular association with the organics compounds. In crystallized clay soils, aggregation stability is higher in 1:1 clay soils (or LAC); the lowest values are generally observed in the lands on 2:1 clay soils (or HAC). Moreover, culture setting generally results in aggregation stability reduction.Cultures intensification (frequent ploughings, low organic matter restitutions to the soil, etc) accentuates aggregation stability loss caused by culture setting, particularly in lands on 2:1 clay soils (or HAC)
Hedde, Mickaël. "Etude de la relation entre la diversité des macro-invertébrés et la dynamique de la matière organique des sols limoneux de Haute-Normandie." Rouen, 2006. http://www.theses.fr/2006ROUES043.
Full textTwo hypothesis were tested in loamy soils located in Haute-Normandie (France) : firstly (H1) macro-detritivore diversity and soil OM are influenced by agricultural and silvicultural managements and secondly (H2) macro-detritivore assemblages influence soil OM dynamics. Relationships were investigated at stand scale and in laboratory microcosms. In forest soils, no relationship between macro-detritivore diversity and C stocks appeared from these empirical results, it arose that macro-detritivore diversity and some holorganic fractions are linked. Results from experimental manipulations show that macro-detritivore effects on beech leaf biodegradation can be split into distinct effects groups. Furthermore, functional diversity, assessed through morphological dissimilarity, rather than species diversity better explains assemblage performances. In agricultural soils, no link clearly appears between these parameters. Regarding laboratory experiments results, eathworm effects on C-CO2 release and soil aggregate OM content and stability depend on species identity and initial soil OM. Furthermore, in low OM soil, increasing species diversity stabilizes C mineralisation and but led to an increase of both aggregate OM content and stability. In conclusion, field results show that macro-detritivore species diversity is driven by soil occupancy rather by system dynamics, thus refuting (H1) hypothesis. Furthermore, soil C stock do not vary during forest rotation while it increase with pasture age, refuting and validating the (H1) hypothesis, respectively. On the other hand, microcosm experiments show that macro-detritivores diversity influences soil OM dynamics, validating (H2) hypothesis
Chen, SongChao. "Cartographie à haute résolution de propriétés du sol à l’échelle de la France métropolitaine : application au carbone organique du sol et à ses potentiels additionnels de séquestration et de stockage." Thesis, Rennes, Agrocampus Ouest, 2019. http://www.theses.fr/2019NSARD088.
Full textThis thesis is a contribution to Digital Soil Mapping (DSM) at broad scale, with applications on the French mainland territory. In Chapter 1, I discussed the main drivers for the rise and development of DSM and gave a brief history about DSM. In Chapter 2, I made a general review about broad-scale DSM by reviewing 160 selected articles from 2003 to mid-2019. I synthetized and discussed the main achievements and challenges for the DSM community. Then I decided to focus on soil organic carbon (SOC) because of its main importance for ecosystem services and global carbon cycle. In Chapter 3, I showed how to improve a national SOC map by merging various SOC maps and provided inputs on how to take advantage of global predictions in ‘data-poor’ countries using a low cost and efficient sampling strategy. Then in Chapters 4 and 5, I focused onthe validity domain of pedotransfer functions used for bulk density predictions and on developing a novel approach to deal with soil thickness prediction over France. I also proposed efficient sampling strategies to improve the accuracy of their predictions. I moved from DSM to Digital Soil Assessment (DSA), exemplified by SOC sequestration potential in Chapter 6 and SOC storage potentials in Chapter 7. They contribute to improving some aspects related to DSM and GlobalSoilMap. In Chapter 8, I finished this thesis by discussing the most important findings of my work and relating them to main challenges of Pedometrics. I outlined the inputs that my work provided to reaching these challenges and highlighted the remaining issues to be solved in
Perveen, Nazia. "Intégration de l'écologie microbienne dans les modèles biogéochimiques : conséquences pour les prévisions du stockage du Carbone et la fertilité des sols." Thesis, Paris 6, 2014. http://www.theses.fr/2014PA066340.
Full textIntegration of the priming effect* (PE) in ecosystem models is crucial to better predict the consequences of global change on ecosystem carbon (C) dynamics and its feedbacks on climate. Over the last decade, many attempts have been made to model PE in soil. However, some basic knowledge to model the PE is lacking such as the relationship between decomposition rate of soil organic matter (SOM) and microbial biomass (MB). Moreover, the PE has never been inserted in a plant-soil model to analyze its role on plant-soil interactions. The main objectives of this thesis were to 1) integrate the activity, biomass and diversity of soil microorganisms in models of ecosystem C and nitrogen (N) dynamics in order to simulate the PE, and 2) determine the consequence of this integration for ecosystem functioning and response to global change. These objectives were achieved thanks to the combination of diverse approaches such as modeling, experimentation and statistical. In a lab experiment, I show that the rate of SOM decomposition increases 1) linearly with MB, and 2) with a saturating effect with SOM content. The linear response of SOM decomposition to MB is explained by the very limited microbial colonization of SOM reserves. However, the positive effect of SOM content on decomposition rate indicates that the local availability of SOM may be limiting for microbial mineralization. The observed co-limitation of SOM decomposition was accurately modeled with the Michaelis-Menten equation. Finally, incorporating this equation in a simple model of soil C dynamics explained how carbon often continuously accumulates in undisturbed soils whereas it reaches steady state in cultivated soils. Moreover, I present the first parameterized PE embedding plant-soil model (SYMPHONY) which provides realistic predictions on forage production, soil C storage and N leaching for a permanent grassland. SYMPHONY also shows that plant persistence depends on a fine adjustment of microbial mineralization of SOM to plant nutrient uptake. This fine adjustment was modeled by considering the destruction of SOM through PE and the interactions between two microbial functional groups: SOM-decomposers and SOM-builders. Moreover, consistent with recent observations, SYMPHONY explains how elevated CO2 induce modification of soil microbial communities leading to an intensification of SOM mineralization and a decrease in the soil C stock
Bernoux, Martial. "Stocks de carbone des sols de l’Amazonie occidentale et leur dynamique lors de la conversion de la foret en pâturage." Orléans, 1998. http://www.theses.fr/1998ORLE2004.
Full textDerrien, Delphine. "Dynamique des sucres neutres dans la rhizosphère et les sols : quantification par approche isotopique et modélisation." Aix-Marseille 3, 2005. http://www.theses.fr/2005AIX30077.
Full textUntil now, only few studies on soil organic matter have coupled dynamic and chemical approaches. Our objective was to achieve this kind of coupled approaches, studying a particular macromolecular class : the soil neutral saccharides. We performed 13C labelling and developed a methodology to quantify 13C in monosaccharides, using GC-C-IRMS. Thus, we were able to quantify the nature, the fluxes and kinetics of rhizodeposition and microbial biosyntheses of neutral sugars. On the long term, we also quantified, in situ, the turn-over of sugars in soils. We synthesized these results, building an innovative model of dynamics of neutral sugar carbon insoils, on time scales ranging from the month to the century
Cauwet, Gustave. "Dynamique de la matière organique dans les milieux marin et polyhalins : son rôle dans les processus géochimiques aux interfaces." Perpignan, 1985. http://www.theses.fr/1985PERP1066.
Full textForest-Drolet, Julie. "Répartition du carbone et de l’azote des fractions de la matière organique du sol sous différents types de rotations, de travail de sol et de sources fertilisantes dans le nord du Québec : effets à long terme." Master's thesis, Université Laval, 2020. http://hdl.handle.net/20.500.11794/66701.
Full textJaffrezic, Anne. "Géochimie des éléments métalliques, des nitrates et du carbone organique dissous dans les eaux et les sols hydromorphes : agriculture intensive et qualité des eaux dans les zones humides en Bretagne /." Rennes : Géosciences Rennes, 1997. http://catalogue.bnf.fr/ark:/12148/cb36176164s.
Full textSaenger, Anaïs. "Caractérisation et stabilité de la matière organique du sol en contexte montagnard calcaire : proposition d'indicateurs pour le suivi de la qualité des sols à l'échelle du paysage." Thesis, Grenoble, 2013. http://www.theses.fr/2013GRENS010/document.
Full textMountain soils are major reservoirs of carbon (C), potentially vulnerable to climate and land use changes that affect them significantly. However, the great variability of these soils, their limited accessibility and the lack of appropriate measurement tools restrict our knowledge. Today, our comprehension of the biogeochemistry of mountain soils remains very incomplete regarding stocks, chemistry and reactivity of soil organic carbon (SOC). Yet this information is necessary to understand the evolution of soil carbon in the current context of global change. The objectives of this work were (i) to gain a better understanding of the nature, stability and vulnerability of SOC in a mosaic of ecosystems in a calcareous massif in the Alps (Vercors massif), (ii) to search for fast and reliable characterization tools, suitable for the study and monitoring of COS at the landscape scale, and (iii) to propose indicators for the assessment and monitoring of soil quality in mountain regions. As a first step, we tested the application of Rock-Eval pyrolysis for the study of COS at large-scale on a set of ecosystem units. Then, we compared the Rock-Eval approach to two conventional techniques for soil organic matter (SOM) study: the particle-size fractionation of SOM, and the mid-infrared spectroscopy. These coupled analytical approaches allowed us to quantify C stocks across the study area, and explain the stability and the vulnerability of COS at various angles. Factors responsible for the patterns observed in the different eco-units are discussed. This work also confirmed the relevance of the Rock-Eval tool to achieve our previous objectives. Biological approaches allowed us to assess the significance of microbial pool in these soils. Finally, indices assessing the status of SOM (SOC storage, soil fertility, vulnerability COS) were proposed and constituted interesting management tools for decision-makers
AITA, CELSO. "Couplage des cycles du carbone et de l'azote dans les sols cultives : etude, au champ, des processus de decomposition apres apport de matiere organique fraiche." Paris 6, 1996. http://www.theses.fr/1996PA066731.
Full textGuenet, Bertrand. "Interactions entre les entrées de matières organiques fraîches et la minéralisation des matières organiques des sols." Paris 6, 2009. http://www.theses.fr/2009PA066445.
Full textClavelin, Pierre. "Contribution à l’étude de la pollution des sols par des composés organochlorés : : préparation de mélanges témoins - : Etude comparative de techniques d'extraction." Lyon, INSA, 1993. http://www.theses.fr/1993ISAL0088.
Full textIn a first step, we have tried to prepare dry or humidified mixtures composed with clays or real soils homogeneously spiked by organochlorine pollutants (Pyralène Tl, chlorophenols). Beyond the homogeneity aspect, we wanted to know if the preparation procedure allow to obtain pollutant adsorption on the absorbent. Finally we propose a protocol (with a rotary evaporator) satisfying the homogeneity critter. However, we observe some pollutant losses and we show that, for dry mixtures, the pollutant is not adsorbed but only coats soil particles. We demonstrate the water effect on adsorption. In a second step, with these synthetic mixtures, we compared the efficiency of four types of extraction techniques: thermal way (micro sublimation, thermal desorption, pyro-injection), by liquid organic solvents (Soxhlet, Soxtec), by carbon dioxide (liquid, gas or supercritical) and by water leaching (at various temperature and pression conditions). Good recoveries are found with techniques using temperature and/or pressure (micro-sublimation) an and an solvent (water, carbon dioxide or organic solvent). As well as adsorption, water influences desorption quality
Noirot-Cosson, Paul-Emile. "Optimisation de l'insertion des Produits Résiduaires Organiques dans les systèmes de cultures d'un territoire francilien : évolution des stocks de carbone organique et substitution des engrais minéraux." Thesis, Paris, AgroParisTech, 2016. http://www.theses.fr/2016AGPT0011/document.
Full textThe use of Exogenous Organic Matter (EOM) in agriculture could be an efficient way to substitute mineral fertilisation and increase soil organic matter (SOM) enhancing soil fertility and storing carbon (C). It could also cause nitrogen (N) pollutions such as nitrate leaching and gas emissions. Better understanding of C and N fate after EOM applications on cropped soils would allow improving these benefits while limiting environmental impacts. This thesis aims at: (i) predicting EOM impacts when applied on cropped soils, (ii) studying the effects of various scenarios of EOM applications in terms of C storage, synthetic N saving and N pollutions in the context of the Plain of Versailles region (221 km²) and taking into account soil diversity, crop successions and soil organic C contents, (ii) studying the potential for improving these benefits at the regional scale with an optimal distribution of EOM. The CERES-EGC crop model was used to simulate the effects of repeated applications of EOM over 13 years on both soil C and N dynamics in the soil-crop-water-air system of the long-term field experiment QualiAgro located within the region. The sub-model NCSOIL was parameterised from C and N mineralisation kinetics of EOM measured in laboratory conditions. When transposing the parameters into the CERES-EGC model, C storage at the field scale was well simulated, together with crop N uptake and yields, as well as soil mineral N contents. The kinetics of C and N mineralisation of the 18 EOM available in the region were used along with EOM biochemical fractionations for parameterising the NCSOIL model. The soil type did not significantly change EOM parameters. Four groups of EOM were distinguished based on their C and N dynamics: (i) stable composts, (2) more reactive and less mature composts and stable manures, (3) manures with reactive OM corresponding to horse manures and (4) very reactive EOM as sludges, litters that should be used as fertilisers. Numerous scenarios of EOM applications, constrained on the phosphorus and N quantities they bring (and limiting the input in trace elements), were simulated for 20 years in all regional contexts of soil, crop successions and soil organic C contents. The soil type was the main factor controlling C storage and N leaching while it was crop successions for N saving. Some composts allowed C storage up to 1.1 t C ha-1 yr -1 reaching 63% of C applied. N saving of 74 kg N ha-1 yr -1 were possible with a dried sewage sludge and a compost. N substitution could reach more than 90% of N applied with EOM, these high percentages being related with the indirect effect of EOM on soil OM and the hypothesis made for N substitution An optimisation model was developed to select EOM application scenario for each crop plot (soil x crop succession x initial soil OC content x area) accounting for EOM availability in the region with the objectives of maximising C storage or synthetic N saving or minimising N leaching at the regional scale. Applying preferentially the most stable EOM on soils with the highest potential for C storage i.e. with the highest calcareous and clay contents, up to 0.47 t C ha-1 yr-1 could be stored. Applying preferentially fertilising EOM on crop succession with maize and amending EOM on succession with rapeseed, up to 53 kg N ha-1 yr -1 could be saved
Zaouche, Mounia. "Modélisation spatiale multi-sources de la teneur en carbone organique du sol d'une petite région agricole francilienne." Thesis, Université Paris-Saclay (ComUE), 2019. http://www.theses.fr/2019SACLS080.
Full textIn this thesis, we are interested in the spatial estimation of the topsoil organic carbon(SOC) content over a small agricultural area located West of Paris. The variability of the SOC contenthas been identified as one of the main sources of prediction uncertainty of SOC stocks, whose increasepromotes soil fertility and mitigates greenhouse gas emissions. We use data issued from heterogeneoussources defined at different spatial resolutions (soil samples, soil map, multispectral satellite images, etc)with the aim of providing on the one hand an exhaustive spatial information, and on the other accurateestimates of the SOC content in the study region and an assessment of the related uncertainties. Severaloriginal models, some of which incorporate the change of support, are built and several approaches andprediction methods are considered. These include recent and powerful Bayesian methods enabling notonly the inference of sophisticated models integrating jointly data of different spatial resolutions butalso the exploitation of large data sets. In order to optimize the quality of prediction of the multi-sourcedata modellings, we also propose an efficient and fast approach : it allows to increase the influence of animportant but under-represented type of data, in the set of all initially integrated data
Barnier, Christophe. "Disponibilité des HAP dans les sols de friches industrielles et influence des conditions rhizosphériques." Thesis, Vandoeuvre-les-Nancy, INPL, 2009. http://www.theses.fr/2009INPL102N/document.
Full textPAHs are present in many industrial wasteland soils. Their remediation using biological techniques remains limited because of their low availability. This work identifies some of the factors controlling this availability in soil and proposes management strategies able to modify it, focusing on plant assisted treatment. First, we have shown that PAHs availability can be estimated by a 30 hours extraction using a Tenax® resin. The analysis of PAHs availability for three wasteland soils showed that the size of black carbon particles, which is the main PAHs reservoir, and the aggregation intensity are the two main availability controlling factors. Laboratory experimentation also showed that this availability can be influenced by rhizosphere parameters. Acidification of a calcareous soil, in dissolving the carbonated cement, can increase PAHs availability by desaggregation. Soil alkalinisation, in decreasing sorption forces between PAHs and the solid matrix, may also increase availability. Citric acid has an effect even more pronounced than the pH alone. Its chelating properties can increase PAHs availability by 40%. Some of these laboratory results have been confirmed by in situ experiments. Indeed, a white lupine culture was able to increase anthracene dissipation for one of the tested wasteland soil over a 5 months period
Belhadj, Brahim Ali. "Influence des constituants alumineux et ferriques non cristallins sur les cycles du carbone et de l'azote dans les sols montagnards acides." Grenoble 2 : ANRT, 1987. http://catalogue.bnf.fr/ark:/12148/cb376027521.
Full textCrème, Alexandra. "Impacts de la gestion des prairies sur le stockage du carbone et la nature biogéochimique des matières organiques du sol." Thesis, Poitiers, 2016. http://www.theses.fr/2016POIT2275/document.
Full textSoil C sequestration reduces the effects of climate change, improves soil quality and food security. Soil organic matter (SOM) could be enhanced by introduction of ley grassland into the cropping cycle. The objective of this PhD thesis was to evaluate the effect of management practices of ley grassland on the quantity, composition and stabilization processes of SOM and greenhouse gas emissions (GHG). My data showed legacy effects of duration and fertilization of the temporary grassland phase on SOM after 3 years of cropping. The duration of grassland phase influenced the quantity and composition of the microbial biomass as well as the nature of SOM. N fertilization during the grassland phase is necessary for soil C sequestration in soil without increasing GHG emissions.To replace mineral N fertilization, legumes may be used in forage production systems. Consequently, I was interested in the effect of introduction of lucerne on C, N and P forms in soils under lucerne-grass mixtures. My results indicate similar soil C stocks under mixtures and grass monocultures, despite the high productivity of lucerne. Molecular biomarkers indicated that the introduction of lucerne in grassland influenced the degradation of the SOM more than its stabilization. Moreover, the presence of lucerne influenced P forms in soils under mixtures.In conclusion, the introduction of ley grasslands into cropping cycles requires careful evaluation of the management practices in order to optimize C storage, GHG emissions and N fertilizer use
Zayani, Hayfa. "Estimations spatiale et temporelle des teneurs en carbone organique des sols agricoles par proxy- détection et télédétection satellitaire : Application à deux sites d’étude en Bretagne et en Tunisie centrale." Electronic Thesis or Diss., Rennes, Agrocampus Ouest, 2023. http://www.theses.fr/2023NSARD104.
Full textProxy-detection and remote sensing sensors in different spectral ranges can contribute to regular quantification of soil organic carbon (OC) content. The aim of this thesis was to assess the ability of Vis-NIR spectroscopic proxy-detection data and/or optical and radar satellite data to predict the spatial distribution and/or temporal evolution of OC content in agricultural soils in two contrasting pedoclimatic contexts, in France and Tunisia. At the study site in Brittany (France), Vis-NIR spectroscopy allowed to identify the direction of variation in OC content over time, as soon as the range of temporal variation was > 2 g.kg-1. In the same study context, the radar signal from Sentinel-1 (S1) could be used to estimate volumetric soil moisture of soils using a linear model (R² = 0.47 - 0.72), with rather high errors (RMSE = 6.1 - 6.5%) but allowing mapping the broad soil moisture conditions within this agricultural landscape.The performance of OC content prediction models, based on Sentinel-2 (S2) images acquired on different dates, appears to be optimal when considering dates corresponding to intermediate (15-18%) to high (>25%) mean volumetric soil moisture content. The use of a time series of S2 data trained by machine-learning models on ground measurements, improved the accuracy of predictions both in Brittany and Tunisia. Furthermore, the coupling of remote sensing data with indices calculated from spectra obtained under laboratory conditions improved OC content prediction performance, particularly in situations where remote sensing time series are not widelyavailable