Water balance for different land use and crop sequences under semiarid environment

2014

Article

Mekki I., Zitouna Chebbi R., Jacob Frédéric, Masmoudi M., Prévot L., Ben Mechlia N., Voltz M., Albergel Jean

Revue des Régions Arides, 2014, 35 (No spécial), p. 769-775 ISSN 0330-7956

Aridoculture et Cultures Oasisennes : Gestion des Ressources et Applications Biotechnologiques en Aridoculture et Cultures Sahariennes : Perspectives pour un ; Développement Durable des Zones Arides : Meeting International, 4., Djerba (TUN), 2013/12/17-19

In semiarid agrosystems, improving management of soil and water resources requires developing reliable means for characterizing the temporal dynamics of soil water balance in a spatially distributed manner. The purpose of this study is to analyze soil water balance in relation to natural drivers (i.e. rainfall and soil properties) and anthropogenic forcing (i.e. land use and crop successions). We focuson a hilly watershed devoted to rainfed agriculture, so-called the Kamech watershed, which is located in the Cap Bon Peninsula, north-eastern Tunisia. The soil moisture analysis is based on in-situ data collected in different fields and during various crop growth cycles under the common cereals/legumes/pasture cropping systems. In-situ data include water balance components and vegetation parameters. The results show that annual rainfall is mainly converted into evapotranspiration during the growing cycle for different land uses. The runoff amounts, for most of the sites, correspond to less than 10% of the rainfall amount. The evapotranspiration ratio significantly differs in relation to soil properties and cumulated rainfall. We observe large differences in soil water dynamics among the legumes (fababean and chickpea) and cereals (wheat, oat, and triticale). Soil water is larger for legume crops, despite substantial plant growth during winter-spring. This is ascribed to the shallow root systems of fababean and chickpea that induces a restricted access to deep water. Despite drought conditions during summer, bare soil following annual pasture and legumes corresponded to larger amounts of soil water as compared to cereals. The amount of available water observed ranges from 0 mm to nearly 100 mm.

Constituants et propriétés des sols [068PROSOL] ; Etude du bilan hydrique et ses applications au suivi hydrique ry-farming et pilotage de l'irrigation [072AGRMET02]

BILAN HYDRIQUE ; EAU DU SOL ; UTILISATION DU SOL ; SYSTEME DE CULTURE ; CULTURE ; RESSOURCES EN EAU ; RESSOURCES EN SOL ; PLUIE ; HUMIDITE DU SOL ; PRECIPITATION ; VARIATION ANNUELLE ; EVAPOTRANSPIRATION ; RUISSELLEMENT ; BASSIN VERSANT ; COLLINE ; GESTION DE L'EAU

TUNISIE

Fonds IRD [F B010076325]

fdi:010076325