Assessing the Effects of Urbanization on Soil Hydrology in Hungary

While the effects of urbanization are widely studied, the effects of soil sealing, particularly in the case of Hungary, have only received limited attention in recent years. Our study aimed at understanding the underutilized capacity of urban soils at the national level. We have applied a 20 m resolution, spatially explicit daily water balance-based methodology to calculate the potential water dynamics for the top 75 cm of the soils currently covered by urban fabric in Hungary, for the time period of 1971–2024. We aimed to utilize primarily publicly available data and open-source software to support further use and development. Our results indicated that these (currently sealed) soil surfaces could allow between 0.14 and 0.29 km3 of water to infiltrate into the soil, equaling about 7% of the estimated annual water withdrawal in Hungary. The on-site evaporation from these surfaces would produce about 400 PJ of total cooling service annually, corresponding to an average of 145 MJ/m2. Our findings highlighted the water storage potential of soils in Hungary, particularly in urban areas, supporting the future application of nature-based solutions and blue-green infrastructure.