Impact of the management of the lower level of urban greenery on water retention in urban ecosystems

The different vegetation covers and management play an important role in improving soil water retention properties. The present research was carried out on the campus lawns of the University of Agriculture , Krakow, Poland, from May to October 2023, to examine the impact of vegetation covers and management, including mowed (A) and non-mowed lawns (B) or flower meadows (C) on soil water retention properties. The experimental plot size for each type of cover was 5 × 5 m 2 . Soil samples were collected monthly to measure water retention properties, such as current water storage capacity (Sa) and water storage capacity after 4 and 24 hours (S4 and S24). The volumetric water content (VWC (%)), soil water infiltration (seconds), soil temperature (ᵒC), air temperature (ᵒC), and humidity (%) were also measured. Parameters related to soil repellency and soil chemical properties , such as the percent nitrogen and carbon, were also determined. The Kruskal-Walli’s test revealed that the air temperature (ᵒC), soil temperature (ᵒC), volumetric water content (%), infiltration (seconds), nitrogen (%), and Sa (%) were statistically different among different vegetation covers A, B, and C. However, air humidity (%), S4 and S24, and carbon (%) were not statistically different in vegetation covers. The flower meadows recorded lower air temperatures (25 ᵒC) and soil temperatures (23 ᵒC), while the mowed lawn recorded higher air and soil temperatures (28 ᵒC and 27 ᵒC). The non-mowed lawn stored maximum VWC (14 %), and the flower meadow plot took the longest time (100 seconds) to infiltrate the water. The highest mean Sa, around 34 %, was observed in flower meadows and non-mowed lawns, while the lowest Sa was calculated in mowed lawns (25.2 %). It is concluded from the results that the establishment of flower meadows and non-mowed lawns should be encouraged in urban areas to conserve soil water, but mainly to reduce the heat island effect and improve the microclimate .