Effects of hydrological regime and land use on in-stream Escherichia coli concentration in the Mekong basin, Lao PDR

In the basin of Mekong, over 70 million people rely on unimproved surface water for their domestic requirements. Surface water is often contaminated with fecal matter and yet little information exists on the underlying mechanisms of fecal contamination in tropical conditions at large watershed scales. The objectives of this paper were to (1) investigate the seasonality of fecal contamination using Escherichia coli as fecal indicator bacteria (FIB), and (2) establish links between the fecal contamination in stream water and its controlling factors (hydrology and land use). The results show the presence of fecal contamination at most of the sampled sites, with a seasonality characterized by higher and extreme E. coli concentrations occurring during the rainy season. The highest E. coli concentrations, strongly correlated with total suspended sediment concentrations, were measured in catchments dominated by unstocked forest areas, especially in mountainous northern Lao PDR and in Vientiane province.

The paper, led by Paty Nakhle, PhD student at GET, was published open access in the Scientific Reports journal.

More news

Articles

Agricultural groundwater with high nitrates and dissolved salts given to pregnant mice alters brain development in the offspring

This new paper, at the interface between environment and health, shows that groundwater contaminated by agricultural inputs from the Indian site of Berambadi (M-TROPICS observatory), significantly impacts the brain development of mice when given to pregnant or lactating mice: fewer neurons, fewer astrocytes (white blood cells in the brain), and more dead cells in the […]

19.08.2021

Articles

Decay Rate of Escherichia coli in a Mountainous Tropical Headwater Wetland

Fecal indicator bacteria like Escherichia coli (E. coli) are widely used to assess water contamination, but their behavior in tropical ecosystems is poorly documented. The main objectives of this study led by Paty Nakhle, PhD student at GET in collaboration with iEES Paris, were to: (i) evaluate decay rates (k) of the total, particle-attached and […]

30.07.2021

Articles

The M-TROPICS CZO releases long-term meteorological, hydrological, sedimentary geochemical, and land use datasets in Cameroon, Lao PDR, and India

The CZO M-TROPICS (Multiscale TROPIcal CatchmentS) investigates the response of tropical catchments to global change based on long-term collection of meteorological, hydrological, sedimentary, geochemical, and land use data in partnership with academic and governmental institutions in various tropical countries. M-TROPICS includes in particular the experimental watersheds of Nyong in Cameroon (1994-), Houay Pano in Lao […]

25.05.2021

Search