Vapor flow control in dune sediments under dry bare soil conditions

Sci Total Environ. 2021 Sep 10:786:147404. doi: 10.1016/j.scitotenv.2021.147404. Epub 2021 Apr 30.

Abstract

The study presents daily values of inward and outward vapor flux crossing the soil-atmosphere boundary in dependence on meteorological parameters and soil moisture. Measurements of vapor flux, soil moisture and meteorological parameters were evaluated during days without rainfall between 2015 and 2019. Vapor flux data were obtained at 1 min intervals by a precision lysimeter installed in the Doñana National Park, southwest Spain. Meteorological data were measured on-site at 10-min intervals, including temperature, relative humidity, wind velocity and net radiation. After manual and automatic noise elimination of the lysimeter data, time series of a summer and winter period were generated for selected relevant parameters. Furthermore, daily cumulative data of inward and outward vapor flux were calculated for the entire period and analyzed for their control by meteorological parameters and soil moisture. Results show moderate correlations of daily outward vapor flux on the diurnal amplitudes of temperature and humidity whereas daily inward vapor indicates moderate correlations with temperature and soil moisture. A correction coefficient for potential evaporation to estimate actual evaporation was determined based on soil moisture and air temperature.

Keywords: Doñana; Evaporation measurements; Nonrainfall-precipitation, bare soil; Precision lysimeter; Vapor adsorption.