A century-long change in vegetation in Zdrojowa Gora interdunal depression, Niepust range, Kampinos National Park (central Poland)

Long-term studies can provide a better understanding of vegetation dynamics. However, the shortage of older datasets means such studies remain uncommon. An exception is the work by Professor Roman Kobendza, who in the 1920s prepared a high-quality sketch of vegetation of the Zdrojowa Gora interdunal depression in Kampinos National Park (KNP), central Poland. He identified 11 plant communities, consisting mainly of open mire, bog, sedge, and meadow vegetation, and drew six 1-m elevation isolines. In the 1920s the area was a wet pasture. Nowadays, the site is abandoned and covered by shrub and forest vegetation arising from sec- ondary succession. The aim of this study was to describe the present state of the vegetation and interpret its past dynamics. The historical spatial vegetation data was georeferenced primarily using microtopography derived from a high-resolution Digital Elevation Model. Fieldwork was carried out in 2022, ca. 100 years after the inventory made by Kobendza, including aerial pho- togrammetry, ground vegetation sampling, and mapping with a high-resolution orthophotomap. Changes in habitat were assessed using environmental indicators values. Significant shifts in vegetation were observed since the original survey, 100-years previously. Non-forest communi- ties were replaced by scrub and forest vegetation. The study area was dominated by Frangula alnus and Betula pubescens. Two plant associations were identified: optimal and terminal phases of buckthorn scrub (Frangulo-Rubetum plicati) and the initial phase of mixed oak-pine forest (Querco-Pinetum). Secondary succession process was interpreted. Based on ecological indicator values, there were registered decreases in light and moisture and an increase in fertility. These results confirm trends of environmental changes taking place in ecosystems at KNP. The study shows that microtopography can be successfully used during geoprocessing of historic surface vegetation data.