Biology subjects

Schaumberger, A.

Publications and source records attributed to Schaumberger, A..

3 recordsLinked to original sources

bioRxiv2025

Global Change Factors differentially impact Floral and Leaf Economic Traits

Background and AimsSince the Industrial Revolution, rising atmospheric CO{square}, warming, and more frequent droughts have significantly impacted ecosystems. While the response of leaf functional traits to these climate change factors have been widely studied, reproductive traits remain relatively understudied, despite their key role in the diversification and distribution of flowering plants. Here, we investigated how elevated CO{square}, warming, drought, and their interactions affect floral, leaf and seed traits in two model grassland species. We also examined how these factors influence trait coordination. MethodsTwo common grassland species, Lotus corniculatus and Crepis capillaris, were sampled from a 10-year climate manipulation experiment. We measured resource economic traits related to organ size, construction cost, and dry matter content in both leaves and flowers, along with seed size and number. Univariate and multivariate analyses were used to assess trait responses, and rank-abundance curves were employed to visualize changes in trait coordination across treatments. Key ResultsTrait responses to climate change factors varied between species. Drought emerged as the most influential factor, affecting only leaf traits in L. corniculatus, but impacting leaf, floral, and seed traits in C. capillaris. Across both species, climate change conditions increased leaf construction costs and reduced flower size. In addition, it led to larger leaves in L. corniculatus, and fewer seeds in C. capillaris. Under extreme climate change conditions, trait coordination became stronger in both species, although C. capillaris showed no coordination response specifically to drought. ConclusionOur results show that floral economic traits, like leaf traits, are responsive to individual and combined effects of climate change factors. This highlights their importance in shaping plant strategies under environmental stress and emphasizes the need to better integrate floral traits into the whole-plant economic framework.

ecology↗

bioRxiv2024

Climate change shapes richness-evenness relationships in a subalpine grassland experiment

Grasslands face an uncertain future due to climate change. Although there is increased interest in the interdependencies of different biodiversity components, the effects of climate change on these relationships remain understudied. One of these is the richness-evenness relationship (RER), which is sensitive to altered species abundances in relation to richness. This relationship may be important as evenness and richness jointly shape diverse ecosystem functions, such as stability and productivity. As evenness affects productivity differently in low and high richness communities, the richness-evenness relationship is important to investigate, especially under climate change. Here, we assess the effects of increased CO2 concentrations, temperature, and drought on the RER in a subalpine long-term (2010 - ongoing) grassland climate change experiment, and test whether these effects can be buffered by reseeding. We provide evidence that climate change alters the RER in our experiment, and that these changes occur independently of changes in richness and evenness separately. Reseeding erases the differences in RER between treatments and controls but fails to restore the negative RER initially found in controls. Further, we show that the dominant grass species in our system (Arrhenatherum elatius) responds differently to each climate change factor, with opposite effects in high vs. low richness plots, thereby largely determining the direction of the RER. These results suggest that the RER can reveal additional insights on community responses to climate change and represents a different signal than evenness or richness alone. A more nuanced approach integrating evenness and maximizing richness in seed mixtures could be an important step forward to better match restoration treatments to particular community types and global change drivers.

ecology↗

bioRxiv2023

Soil fungi remain active and invest in storage compounds during drought independent of future climate conditions

Microbial growth is central to soil carbon cycling. However, how microbial communities grow under climate change is still largely unexplored. In an experiment simulating future climate conditions (increased atmospheric CO2 and temperature) and drought, we traced 2H or 18O applied via water-vapor exchange into fatty acids or DNA, respectively, allowing to measure community- and group-level adjustments in soil microbial physiology (replication, storage product synthesis, and carbon use efficiency, CUE). We show, that while overall community-level growth decreased by half during drought, fungal growth remained stable demonstrating an astonishing resistance of fungal activity against soil moisture changes. In addition, fungal investment into storage triglycerides increased more than five-fold under drought. CUE (the balance between anabolism and catabolism) was unaffected by drought but decreased in future climate conditions. Our results highlight that accounting for different growth strategies can foster our understanding of soil microbial contribution to C cycling and feedback to climate change.

microbiology↗