Král, Přemysl, Jan Douda, Ferenc Horváth, Remigiusz Pielech, Michal Slezák (2023): Alder carrs in Central Europe - NERVE4 monitoring project. Faculty of Environmental Sciences, Czech University of Life Sciences Prague


The Network Establishment for V4 Wetland Forest Protection (NERVE4 Action) is an innovative project focused on safeguarding the wetland forests within the Visegrád Four (V4) nations: the Czech Republic, Slovakia, Poland, and Hungary. This initiative was born out of an increasing awareness of the need for wetland forest conservation and the potential threats posed by climate change to these native habitats and species. To this end, NERVE4 Action has worked on monitoring the changes in alder carrs under varying environmental conditions, sharing insights into biodiversity loss, and fostering collaboration in scientific research. Such efforts are crucial for developing informed, effective conservation strategies. 

In each participating country, a specific site has been designated for ongoing environmental monitoring and seasonal vegetation analysis. Our methodology, adapted from Douda (2021), involves the annual sampling of ten randomly selected hummocks at each site. These hummocks are further segmented into zones based on 20 cm intervals, differing in water availability. Additionally, an 8-meter diameter area surrounding each hummock is examined to capture the broader vegetation characteristics of the site. To accurately measure environmental variables, TOMST loggers with protective cages are installed at the top and bottom of each hummock to track humidity, while Solinst Level loggers are employed at each site to continually monitor water levels. Our observations indicate significant interseasonal water level fluctuations. We also gather data on light availability and hummock density. The primary objective is to link species variations with changes in water levels across diverse climatic zones. 

For the most recent updates and information about the project, please visit our website at:


Ócsai Turjános Forest Reserve – Hungarian site 

Water level fluctuations at Ócsa, 2022-2023

Other hungarian sites described briefly:
Csörnyeberek and Baláta-tó Forest Reserves


ER Archívum - digitális
Alder carrs in Central Europe
Első szerző
Přemysl Král