The surface of the floodplain serves as a vadose zone boundary where water infiltrates, evaporates, or returns to the river, and sediments accumulate or are eroded. The discharge of the Middle Rio Grande has been altered by the construction of Cochiti Dam and the implementation of levees. Hydraulic connectivity in the Middle Rio Grande floodplain is perhaps most apparent at a small local wetland and a low-lying trough with a high water table capable of causing seeping floods. The objective of this study was to determine if inundation patterns impact the hydraulic and physical properties of floodplain soils. A study was designed that would test the soil texture, infiltration rates, and hydraulic conductivity at flooding and non-flooding areas within the Middle Rio Grande Floodplain. The statistical difference among the variables with respect to flooding frequency was determined by non-parametric Mann Whitney U tests. No significant difference was found among saturated hydraulic conductivity values or infiltration rates. A greater distinction among flooding and non-flooding areas was noted between the infiltration rates measured under unsaturated conditions than under saturated conditions. The infiltration rates measured under unsaturated conditions were, in general, greater at the non-flooding areas. The difference in the percent of fine particles in flooding and non-flooding areas was significant, suggesting one way in which inundation patterns affect the physical properties of floodplain soils.
floodplain, inundation patterns, Middle Rio Grande
Stauffer, Sophie J.. "Inundation Patterns and Their Effect on the Physical and Hydraulic Properties of Floodplain Soils in the Middle Rio Grande Floodplain." (2014). http://digitalrepository.unm.edu/wr_sp/125