Moss abundance increased along a gradient of postfire interventions from high to low intensity after a forest fire in Brandenburg, Germany

Abstract

Abstract The intensity and frequency of forest fires are increasing in the cultural landscape of central Europe as the climate is becoming warmer and drier. This requires an understanding of natural regeneration processes in forests and the effects of traditional and new approaches to restoring fire-damaged forests; however, it warrants more research in Germany, where large-scale stand-replacing fire is a new phenomenon in recent times. Specifically, early successional plant pioneer communities, such as mosses, influence the regenerating forest system, by providing viable conditions and habitats for subsequent plant species. The present work focuses on the processes that take place in the moss communities undergoing management interventions of a gradient of intervention intensities after fire disturbance. In a plot-based field inventory, we investigated early successional moss communities three years after a forest fire in Brandenburg, Germany. The study area was subjected to various postfire interventions: high intensity site preparation and dense row planting, natural regeneration (no intervention), and a moderate site preparation in combination with low-density group planting approach. Utilizing Bray–Curtis-based nonmetric multidimensional scaling to assess similarities among postfire moss communities, a simplification of moss communities under high-intensity postfire intervention was observed. We found that the diversity and abundance of mosses decreased with the application of high-intensity postfire intervention but increased with the application of moderate postfire interventions. Furthermore, we found a higher share of light-demanding pioneer mosses in areas under high intensity postfire intervention. In areas under moderate or no postfire intervention, more shade-tolerant species were present. We conclude that moderate interventions with low-intensity site preparation and group planting resulted in reduced losses of moss species and coverage in the successional moss community.