Examining the groundwater turnover in a lowland salt steppic oak forest

Over the past centuries, many changes have occurred in addition to climate change, from human encroachment to deforestation and drainage, and much more. Research has shown that lowland forests use a significant amount of groundwater, without which it is much harder to imagine their existence, even as a dominant source of water. It is therefore crucial to understand how much and how forests can be maintained under the expected conditions, because groundwater levels are sinking year by year in large parts of the Hungarian lowlands.

From a conservation perspective, it is also crucial to investigate the activities taking place in the Ohat oak forest, which is a remnant area along the Tisza. Two groundwater wells were drilled in the region in 2021, and automated measuring equipment was put in each of them to track the daily variations in groundwater levels. In order to estimate the groundwater abstraction from the forest, we will utilize the White method to compute the groundwater recharge during times when there is no precipitation.

Additionally, we will look at how the local conditions have changed in relation to the region's long-term meteorological data series. We will be able to compare the soil water recharge in various years thanks to the multi-year data series, and search for connections between the recharging and the monthly and yearly weather conditions. We will also compare the summer and winter periods of the recharging.

This three years are very good for the examination, because there was also drought and wet years, the groundwater level was deeply subslided, and after that, in 2023, it was recharged a lot, because of the rainy weather. These conditions caused a big difference between every year’s recharging, which is instructive for the ecosystem functioning.

The following joint projects (143972SNN project and the TKP2021-NKTA-43 project) supported the preparation of this paper. TKP2021-NKTA-43 has been implemented with the support provided by the Ministry of Innovation and Technology of Hungary (successor: Ministry of Culture and Innovation of Hungary) from the National Research, Development and Innovation Fund, financed under the TKP2021-NKTA funding scheme.