Monitoring of soil moisture response as part of the ecohydrological cycle

Ecohydrological cycle in addition to common hydrological components such as rainfall, runoff and evaporation, strongly focuses also on ecological elements, i.e. elements of the nature and their role in the water cycle. As such we have addressed the role of two natural elements in the water balance of the study plot: vegetation (trees) through rainfall interception process and the soil through water infiltration and soil moisture dynamics. The study plot covers small urban park in the city of Ljubljana, Slovenia and includes the opening with low-cut grass, group of birch trees and group of pine trees. There we are monitoring rainfall and its characteristics, as well as throughfall and stemflow under each group of trees since the year 2014. Additionally, in 2021 we have started to measure also soil moisture (volumetric water content; VWC) at three depths (16 cm, 51 cm and 74 cm) and at three locations: in the open, under the birch and under the pine trees. During the measurements of soil moisture, we have captured the distinctly dry period of spring and summer of 2022, as well as excess of rainfall amount according to the long-term average during September 2022. For the collected data set we have used statistical approaches to analyse influence of vegetation (rainfall interception) on values and response of soil moisture as well as influence of pre-event conditions on the response and dynamics of soil moisture.

Acknowledgments: Results are part of the CELSA project entitled “Interception experimentation and modelling for enhanced impact analysis of nature-based solution” and research programmes and projects P2-0180, J6-4629, and N2-0313 financed by the Slovenian Research Agency (ARRS).