Ökologische Mechanismen bei der Veränderung von Diversität entlang von Landnutzungsgradienten in temperaten Wäldern - vom Baum zur Waldlandschaft

• Antragsteller: Professor Dr.-Ing. Peter Krzystek; Professor Dr. Jörg Müller, seit 10/2017
• Fachliche Zuordnung: Ökologie und Biodiversität der Tiere und Ökosysteme, Organismische Interaktionen ; Forstwissenschaften
• Förderung: Förderung von 2017 bis 2021
• Projektkennung: Deutsche Forschungsgemeinschaft (DFG) - Projektnummer 323939992

• Erstellungsjahr: 2021

Zusammenfassung der Projektergebnisse

Land-use intensity in forests heavily alters the composition and architecture of trees, the structure of forest stands and the configuration of forest landscapes, all of which are assumed to heavily influence species diversity. However, it is disputed whether heterogeneity in forest structures only has positive effects, or whether it might also have negative effects on withinand between stand diversity. For now, finding a definite answer to this question has been hampered by the focus on only few species groups and by the lack of easy-to-assess structural information. Here, we compiled trait and phylogenetic information about a large set of species as well as structural measures across five forest regions, which should give a holistic overview of the relationships between diversity and forest structure. Moreover, we assessed the potential of RADAR to inform about forest structure at the stand level. Although it is not able to depict structural changes in the same resolution as ALS, the main axes of forest structure were good enough represented to model the diversity of the forests. The successful validation with external data further underlines its great potential of Radar as a tool in predicting biodiversity across space and time. We found that structural and floristic aspects of forests determine species turnover even at country-wide extents, though the relative importance of non-environmental filters, i.e. dispersal limitations, increase with decreasing dispersal ability of the species group. Within a region, variations in herb or tree species composition had on average a stronger influence on the turnover of species than forest physiognomy, though this influence became less important with increasing body size and trophic position. Though we already could assess the relative importance of physiognomy on species turnover, assessing whether heterogeneity affects turnover positively or negatively is ongoing work. Vertical and horizontal heterogeneity are the major facets of heterogeneity in forests and affect the species richness of groups from all guilds. However, we could not identify any generalizable mechanism based on trophic position or dispersal ability, which determines under which condition species richness shows positive, unimodal, or negative relationships with heterogeneity. Although both increased species richness of the majority of groups, some responded negatively, which cautions against a wide-ranging establishment of fine-scaled heterogeneity in forest structures. Unfortunately, the applicability of functional traits in predicting species responses to changes in physiognomy has been hindered by the lack of big trait databases for some of the groups and requires more measurements.

Projektbezogene Publikationen (Auswahl)

• (2019) Radar vision in the mapping of forest biodiversity from space. Nature Communications, 10, 1–10
  Bae, S., Levick, S.R., Heidrich, L., Magdon, P., Leutner, B.F., Wöllauer, S., Serebryanyk, A., Nauss, T., Krzystek, P., Gossner, M.M., Schall, P., Heibl, C., Bässler, C., Doerfler, I., Schulze, E.-D., Krah, F.- S., Culmsee, H., Jung, K., Heurich, M., Fischer, M., Seibold, S., Thorn, S., Gerlach, T., Hothorn, T., Weisser, W.W. & Müller, J.
  
• (2020) Heterogeneity–diversity relationships differ between and within trophic levels in temperate forests. Nature Ecology & Evolution, 4, 1204–1212
  Heidrich, L., Bae, S., Levick, S., Seibold, S., Weisser, W., Krzystek, P., Magdon, P., Nauss, T., Schall, P., Serebryanyk, A., Wöllauer, S., Ammer, C., Bässler, C., Doerfler, I., Fischer, M., Gossner, M.M., Heurich, M., Hothorn, T., Jung, K., Kreft, H., Schulze, E.-D., Simons, N., Thorn, S. & Müller, J.
  
• (2021) Dispersal ability, trophic position and body size mediate species turnover processes: Insights from a multi-taxa and multi-scale approach. Diversity & Distributions 27(3). 439– 453
  Bae, S., Heidrich, L., Levick, S. R., Gossner, M. M., Seibold, S., Weisser, W. W., Magdon, P. Serebryanyk, A., Bässler, C. Schäfer, D., Schulze, E.-D., Doerfler, I., Müller, J., Jung, K., Heurich, M., Fischer, M., Roth, N., Schall, P., Boch, S. Wöllauer, S., Renner, S.C. & Müller, J.
  
• (2021) The effect of environmental heterogeneity on communities, Dissertation Universität Würzburg
  Heidrich, L.