Soil hydraulic properties - Martin County

Lubbock scientists from the Wind Erosion and Water Conservation Research unit have an extensive project in Martin County in collaboration with various stakeholders/producers. Our main objective is to identify agronomic management systems that maximize dryland cotton lint yield per unit of water stored in the soil. In this process we use mechanistic simulation models as tools to help us understand the interactions between the soil, the crop, and the climate. A fundamental input to these simulation models is the soil physical properties for a given soil type/series. We collected soil cores, three replicates, as a function of depth at two sites, Massey and Odum. On each soil sample we measured soil texture (sand, silt, and clay), soil bulk density, soil organic matter and the saturated hydraulic conductivity. These measurements were done using well established methods. The relation between soil water potential and volumetric soil water content – the soil moisture release curve – and the relation between unsaturated hydraulic conductivity and volumetric soil water content were calculated using the Van Genuchten method. Further, input functions to the ENWATBAL model that characterize the soil hydraulic properties were tabulated in the required format. All measured and calculated values for the two sites at Odum and Massey are given in graphical and tabular format.