رسالة جامعية
Characterization and contribution of colloidal fraction in the mobility and bioavailability of sedimentary phosphorus ; Caractérisation et contribution de la fraction colloïdale dans la mobilité et la (bio)disponibilité du phosphore sédimentaire
| العنوان: | Characterization and contribution of colloidal fraction in the mobility and bioavailability of sedimentary phosphorus ; Caractérisation et contribution de la fraction colloïdale dans la mobilité et la (bio)disponibilité du phosphore sédimentaire |
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| المؤلفون: | Nguyen, Ngoc Diep |
| المساهمون: | PEIRENE (PEIRENE), Institut Génomique, Environnement, Immunité, Santé, Thérapeutique (GEIST), Université de Limoges (UNILIM)-Université de Limoges (UNILIM), Université de Limoges, Véronique Deluchat, Malgorzata Grybos |
| المصدر: | https://theses.hal.science/tel-03905225Test ; Earth Sciences. Université de Limoges, 2020. English. ⟨NNT : 2020LIMO0078⟩. |
| بيانات النشر: | HAL CCSD |
| سنة النشر: | 2020 |
| المجموعة: | Université de Limoges: HAL |
| مصطلحات موضوعية: | Dam reservoir, Organic matter, Iron, Redox, Drying/rewetting, Anoxia, Water-level fluctuation, Spatial variability, Bioavailability, Mobility, Phosphorus, Colloid, Sediment, Phosphore, Colloïde, Sédiment, Retenue de barrage, Matière organique, Fer, Oxydo-réduction, Cycle séchage/humidification, Anoxie, Marnage, Variabilité spatiale, Biodisponibilité, Mobilité, [SDU.STU]Sciences of the Universe [physics]/Earth Sciences |
| الوصف: | The mobilization of phosphorus (P) from sediment is a persistent internal nutrient source sustaining eutrophication, especially in reservoir. Current knowledge about sedimentary P release does not consider colloidal form, although it is well-known for its efficiency as P-carrier, its high mobility and potentially bioavailability. This thesis provides new constraints to place sedimentary colloids and sedimentary colloidal P into light concerning their important stock and release potential in the reservoir. Colloids are shown to be an intrinsic component of reservoir sediment, and their recovery under sediment resuspension indicated the contribution of water mobilizable colloids up to 2.3 % of the sediment mass in Champsanglard dam reservoir (Creuse, France). The amount of P associated with colloids was up to 6 % of total sedimentary P and 80 % of water-mobilizable P. After the application of different protocols for colloid extraction, separation and for sediment storage, a framework for selecting appropriated method for colloid recovering from a sediment is proposed. The recommendation for colloid recovery is to work with wet sediment, avoid using high-power extraction protocol (i.e. sonication), using filtration with pre-separation step instead of successive centrifugation to avoid under or overestimation in quantity and quality of recovered colloids. The quantity and quality of sedimentary colloids and associated P varied spatially in the reservoir according to sediment size grain distribution and the influence of flow hydrodynamics, the presence of tributaries and fluctuations in the water-level. The highest content of water mobilizable colloids and especially large colloids (0.2 - 1 μm) were found in lacustrine bottom sediments, downstream of the tributary confluence. Bank sediments impacted by water-level fluctuations released P in bioavailable forms (dissolved P and small/nano P-colloids). Under anoxic condition, the potential of sediment to mobilize colloidal P was significantly higher than truly dissolved ... |
| نوع الوثيقة: | doctoral or postdoctoral thesis |
| اللغة: | English |
| العلاقة: | NNT: 2020LIMO0078; tel-03905225; https://theses.hal.science/tel-03905225Test; https://theses.hal.science/tel-03905225/documentTest; https://theses.hal.science/tel-03905225/file/2020LIMO0078.pdfTest |
| الإتاحة: | https://theses.hal.science/tel-03905225Test https://theses.hal.science/tel-03905225/documentTest https://theses.hal.science/tel-03905225/file/2020LIMO0078.pdfTest |
| حقوق: | info:eu-repo/semantics/OpenAccess |
| رقم الانضمام: | edsbas.EA7A8F2B |
| قاعدة البيانات: | BASE |
| الوصف غير متاح. |