Analisi della stabilità temporale dell’umiditá del suolo in un piccolo bacino dolomitico - Temporal stability of surface soil moisture in a small alpine catchment.

This paper aims at assessing the temporal stability of soil water content in a small alpine basin located in the Italian Dolomites. Soil moisture data were collected within two experimental hillslopes over two field campaigns carried out in summer 2005 and 2006. An impedance probe, which allows measurement of volumetric water content at 6 cm depth, was used. In the paper spatial distribution of soil moisture patterns is observed and analyzed by different approaches: i) visually, by comparing interpolated maps of soil moisture at different times; ii) statistically, by assessing the ranking stability and analyzing autocorrelation values and linear regression parameters. Results show that soil moisture patterns are temporally stable over the two experimental hillslopes both in 2005 and 2006. The ranking stability analysis allows to detect, at least in one site, a CASMM area (Catchment Average Soil Moisture Monitoring sites), which is representative of the average soil moisture conditions of the whole hillslope. The linear regression analysis and the high autocorrelation values suggest a strong temporal stability of moisture patterns; correlations are higher for 2005 data reflecting a different distribution of rainfall events between the two years studied.