These data correspond to a non-systematic monitoring of dissolved, particulate or total organic carbon contents in water (rain, surface overflow, underground water) in the Roujan catchment area.

The physico-chemical parameters measured in the Roujan basin and accessible via the data portal concern the measurement of elements such as pH, redox potential, temperature and conductivity, carried out during sampling in the basin.

The Kamech basin is located north of Cap-Bon, in the governorate of Nabeul, on the border between the sub-humid and semi-arid Mediterranean climates. The average inter-annual rainfall is about 640 mm and the potential evapotranspiration is 1300 mm. The outlet of the basin is occupied by a hilly lake built in 1994 (140,000 m3 of initial capacity). The inter-annual flow coefficient is of the order of 10%-15% and the erosion of 15 t/ha/year. Land use is characterised by a cultivation rate close to 75% with, in order of importance: cereals, legumes and irrigated market gardening. This basin has been the subject of a monitoring of anthropogenic activities (land use and management, agricultural practices...), of agro-climatic variables, and of runoff and erosion since 1994 (+ pesticides more recently) at its outlet and since 2005 on 4 substations. This watershed is part of a network of 27 watersheds monitored under an agreement with the Tunisian Ministry of Agriculture (DGACTA).

The water table depth from the soil surface is measured at different points in the Kamech catchment. In Kamech site, the groundwater is shallow with a free surface water table rising and falling in the soil and subsoil layers. The measurements are made at different points in the catchment with piezometers. A piezometer is a perforated PVC tube at its base installed in the soil through a borehole. In every piezometer, the water table depth is measured by manual piezometric probe or monitored at high frequency (~15') with autonomous and automatic probe integrating acquisition units. Through the OMERE data portal accessible from this website, the data can be downloaded from an interactive map.

Pesticide contents are determined on the suspended matter extracted by filtration (0,7µm) in runoff water. Contents allow quantification of particula transport of pesticides and allow too compare it to solute transport.

Runoff and stream flow discharge have been monitored since 1994 at the outlet of the Kamech catchment, and since 2005 at four sub-catchment hydrological stations. Automatic sensors continuously collected and transmitted water level time series to servers in Montpellier (France). Verification and correction processes on the raw data, as well as the generation of elaborated data (e.g. calculation of runoff, discharge from water levels, modification of time steps, etc) are applied before integration of the data sets into the HYSAE database. The time series can be downloaded from an interactive map through the OMERE data portal accessible from this page.

A flow tower is installed on the watershed of Roujan as well as a meteorological station of the AgroClim service unit (INRAE). At these points a set of sensors are arranged in order to collect various meteorological variables such as wind speed, air humidity and temperature, global radiation or evapotranspiration. Just like the other measurements made on the basin by sensors, data acquisition units record the values which are transmitted several times a day to our servers at the INRAE centre in Montpellier or retrieved via Agroclim's webservice. R routines are then used to process these data and prepare them for integration into the HYSAE database of the LISAH, thus integrating them into the information system for OMERE. Through the OMERE data web portal, the address of which is given in this fact sheet, the data can be consulted and downloaded.