Keywords
Hydrology, water quality, remote sensing, modeling, large tropical watersheds, diarrheal diseases
Profile and skills required
We are looking for a candidate motivated by research in Earth science. She or he must have a Master or Engineer degree in one of the following disciplines: environmental sciences, hydrology, and/or hydrogeology, and have a proven experience with programing: data processing, remote sensing, hydrological models. He or she must be fluent in English, both written and spoken.
Application link : https://edd-projets.utoulouse.fr/
Niveau d’anglais requis: Intermédiaire supérieur: Vous pouvez utiliser la langue de manière efficace et vous exprimer précisément.
Project description
Waterborne diseases such as diarrhea are still a major concern in tropical regions and are most often caused by the ingestion of an infectious agent, like fecal pathogenic bacteria. Since the occurrence of fecal bacteria and their fate in the environment depend on biotic and abiotic drivers such as land use, soil type, climate, and hydrology, global change, namely climate change and land use change, alters the processes driving bacteria fate and transport in the environment. In general, few studies were conducted so far to assess the fate and transport of fecal bacteria in tropical environments. In Lao PDR, few studies were conducted on large rivers and the spatialization on the large catchment scale is still necessary to generalize processes and predict health risk, for example at national scale. In West Africa, pollution point-sources, that do not always coincide with suspended matter loads, have been shown to have an important impact, for example in urban areas. In addition, the extrapolation of the results beyond the studied sites remains a challenge, because of the large variability of the surface water characteristics and their environment.
This PhD thesis proposition aims at better understanding the transport and the fate of the fecal bacteria in tropical environments and for large spatial scales. The methodology suggested to implement this thesis will be based, on one hand, on the statistical analysis of the relationship between long-term monitoring in situ data from M-TROPICS and AMMA-CATCH CZOs, and remote sensing data (Sentinel-2 and 3, Landsat-8 and 9), and on the other hand, on numerical modeling, such as SWAT+, to describe the fate of fecal bacteria on large catchment scales (Mekong, Niger or Senegal). The model will allow testing scenarios and evaluate health risk.
The thesis will be jointly supervised by Laurie Boithias (GET, University of Toulouse) and by Kyunghwa Cho (E2AI, Korea University), and will be performed at the GET laboratory (https://www.get.omp.eu/), including a mandatory up-to-12-months mobility at the Environment and E2AI laboratory (https://weilunist.creatorlink.net/), and possible missions to Lao PDR and West Africa.
We are looking for a candidate motivated by research in Earth science. She or he must have a Master or Engineer degree in one of the following disciplines: environmental sciences, hydrology, and/or hydrogeology, and have a proven experience with programing: data processing, remote sensing, hydrological models. He or she must be fluent in English, both written and spoken.
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