Traditionally focussed on maximising productivity, forest management increasingly has to consider other functions performed by the forest stands, such as biodiversity conservation. Terrestrial plant communities typically possess a hump-back relationship between biomass productivity and plant species richness. However, there is evidence of a reverse relationship in forests dominated by beech, one of the most competitive and widespread tree species in temperate Europe. To fully explore the tree productivity-species richness relationship, we investigated above- and below-ground drivers of understorey plant species richness. We focussed on managed beech forests growing along an elevation gradient in Central Europe. We found that the lowest understorey plant diversity was under conditions optimal for beech. Tree fine root mass, canopy openness, soil C/N ratio, the interaction between tree fine root mass and stoniness, and stand structural diversity explain the variation of understorey species richness. We show that the competition for soil resources is the main driver of plant species diversity in managed forests; maximising beech growth in optimal conditions may thus come at the expense of understorey plant richness.

• Klíčová slova
• Below-ground competition, Biomass-richness relationship, Fagus sylvatica, Fine roots, Understorey vascular plant richness,
• MeSH
• biodiverzita MeSH
• buk (rod) * MeSH
• lesy MeSH
• půda chemie   MeSH
• stromy * MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• půda MeSH

QUESTION: What is the impact of simulated historical tree litter removal on understorey plants and soil properties in a temperate deciduous forest? What is the role of seasonal timing of tree litter removal on understorey plants? LOCATION: Podyjí National Park, Czech Republic. METHODS: We conducted an experiment in a randomized complete block design of 45 plots (5 × 5 m). Each block (N = 15) consisted of one plot for each of the three treatments. Treatments consisted of (i) tree litter removal during spring, (ii) tree litter removal during autumn, or (iii) no litter removal as control treatment. These treatments were repeated for a duration of four years. In each plot we recorded the understorey plant species composition and collected soil samples prior to treatment (year 0) and in each subsequent year (years 1-4). Temporal trends in species richness were analysed using repeated measures ANOVAs. The impact of the treatments on vegetation composition over time was analysed using Principal Response Curves. RESULTS: Total species richness per plot significantly changed over time, but this was not related to treatment. Annual species richness increased significantly, but only for the autumn treatment. Annual species also showed the highest inter-annual variation. Endangered species were not affected. When compared to the control treatment, the effect of autumn raking on species composition was stronger than the effect of spring raking. Although the amount of removed nutrients substantially exceeded ambient nitrogen input, no changes in soil conditions were detected. CONCLUSIONS: The season in which tree litter removal took place had a small but significant impact on the understorey vegetation, in particular affecting the germination and establishment of annual species. The large inter-annual variation in species richness calls for a long-term field experiment. The removal of nutrients via litter raking greatly exceeds atmospheric nutrient deposition, warranting a further investigation of litter raking as a potential tool for forest conservation.

• Klíčová slova
• Central Europe, Conservation management, Litter raking, Permanent plots, Species diversity, Temperate woodland, Traditional management, Vascular plants,
• Publikační typ
• časopisecké články MeSH