TY - GEN A1 - Ma, Yunyao A1 - Weber, Bettina A1 - Raggio Quílez, José A1 - Colesie, Claudia A1 - Veste, Maik A1 - Bader, Maaike Y. A1 - Porada, Philipp T1 - Determining key drivers of the annual carbon budget of biocrusts in different climatic zones T2 - EGU General Assembly 2022, Vienna, Austria & Online | 23–27 May 2022 N2 - Biocrusts are distributed over all climate zones of the world and they substantially contribute to ecosystem functioning. Their growth, determined by their carbon balance, can be affected by various climatic drivers. The effects of individual drivers are clear from laboratory experiments, but the relative importance of different drivers along climatic gradients and their underlying mechanisms are largely unknown. Moreover, the effects of seasonal acclimation on the annual carbon balance are not fully understood either. Therefore, we aim at determining the level and variation of annual biocrust carbon balances and their connection to climatic drivers along environmental gradients. In addition, we explore the role that acclimation plays in the carbon balance of biocrusts KW - biocrusts, photosynthesis, carbon Y1 - 2022 UR - https://meetingorganizer.copernicus.org/EGU22/EGU22-3714.html U6 - https://doi.org/10.5194/egusphere-egu22-3714 ER - TY - GEN A1 - Ma, Yunyao A1 - Weber, Bettina A1 - Kratz, Alexandra A1 - Raggio, José A1 - Colesie, Claudia A1 - Veste, Maik A1 - Bader, Maaike Y. A1 - Porada, Philipp T1 - Exploring environmental and physiological drivers of the annual carbon budget of biocrusts from various climatic zones with a mechanistic data-driven model T2 - Biogeosciences N2 - Biocrusts are a worldwide phenomenon, contributing substantially to ecosystem functioning. Their growth and survival depend on multiple environmental factors, including climatic ones, and the relations of these factors to physiological processes. Responses of biocrusts to individual environmental factors have been examined in a large number of field and laboratory experiments. These observational data, however, have rarely been assembled into a comprehensive, consistent framework that allows quantitative exploration of the roles of multiple environmental factors and physiological properties for the performance of biocrusts, in particular across climatic regions. Here we used a data-driven mechanistic modelling framework to simulate the carbon balance of biocrusts, a key measure of their growth and survival. We thereby assessed the relative importance of physiological and environmental factors for the carbon balance at six study sites that differ in climatic conditions. Moreover, we examined the role of seasonal acclimation of physiological properties using our framework, since the effects of this process on the carbon balance of biocrusts are poorly constrained so far. We found substantial effects of air temperature, CO2 concentration, and physiological parameters that are related to respiration on biocrust carbon balance, which differ, however, in their patterns across regions. The ambient CO2 concentration is the most important factor for biocrusts from drylands, while air temperature has the strongest impact at alpine and temperate sites. Metabolic respiration cost plays a more important role than optimum temperature for gross photosynthesis at the alpine site; this is not the case, however, in drylands and temperate regions. Moreover, we estimated a small annual carbon gain of 1.5  by lichen-dominated biocrust and 1.9  by moss-dominated biocrust at a dryland site, while the biocrusts lost a large amount of carbon at some of the temperate sites (e.g. −92.1 for lichen-dominated and −74.7  for moss-dominated biocrust). These strongly negative values contradict the observed survival of the organisms at the sites and may be caused by the uncertainty in environmental conditions and physiological parameters, which we assessed in a sensitivity analysis. Another potential explanation for this result may be the lack of acclimation in the modelling approach, since the carbon balance can increase substantially when testing for seasonally varying parameters in the sensitivity analysis. We conclude that the uncertainties in air temperature, CO2 concentration, respiration-related physiological parameters, and the absence of seasonal acclimation in the model for humid temperate and alpine regions may be a relevant source of error and should be taken into account in future approaches that aim at estimating the long-term biocrust carbon balance based on ecophysiological data. Y1 - 2023 UR - https://bg.copernicus.org/articles/20/2553/2023/bg-20-2553-2023.html U6 - https://doi.org/10.5194/bg-20-2553-2023 SN - 1726-4189 VL - 20 IS - 13 SP - 2553 EP - 2572 ER - TY - GEN A1 - Porada, Philipp A1 - Bader, Maaike Y. A1 - Berdugo, Monica B. A1 - Colesie, Claudia A1 - Ellis, Christopher J. A1 - Giordani, Paolo A1 - Herzschuh, Ulrike A1 - Ma, Yunyao A1 - Launiainen, Samuli A1 - Nascimbene, Juri A1 - Petersen, Imke A1 - Raggio Quílez, José A1 - Rodríguez-Caballero, Emilio A1 - Rousk, Kathrin A1 - Sancho, Leopoldo G. A1 - Scheidegger, Christoph A1 - Seitz, Steffen A1 - Van Stan, John T. A1 - Veste, Maik A1 - Weber, Bettina A1 - Weston, David J. T1 - A research agenda for non-vascular photoautotrophs under climate change T2 - New Phytologist N2 - Non-vascular photoautotrophs (NVP), including bryophytes, lichens, terrestrial algae, and cyanobacteria, are increasingly recognized as being essential to ecosystem functioning in many regions of the world. Current research suggests that climate change may pose a substantial threat to NVP, but it is highly uncertain to what extent this will affect the associated ecosystem functions and services. Here, we propose a research agenda to address this urgent question, focusing on physiological and ecological processes that link NVP to ecosystem functions while also taking into account the substantial taxonomic diversity across multiple ecosystem types. Accordingly, we developed a new categorization scheme, based on microclimatic gradients, which simplifies the high physiological and morphological diversity of NVP and worldwide distribution with respect to several broad habitat types. We found that habitat-specific ecosystem functions of NVP will likely be substantially affected by climate change, and more quantitative process understanding is required on (1) potential for acclimation (2) response to elevated CO2 (3) role of the microbiome and (4) feedback to (micro)climate. We suggest an integrative approach of innovative, multi-method laboratory and field experiments and eco-physiological modelling, for which sustained scientific collaboration on NVP research will be essential. KW - biocrusts KW - climate change KW - ecosystem services KW - epiphytes KW - functional traits KW - lichens and bryophytes KW - model–data integration KW - nonvascular vegetation Y1 - 2022 U6 - https://doi.org/10.1111/nph.18631 SN - 0028-646X SN - 1469-8137 VL - 237 (2023) IS - 5 SP - 1495 EP - 1504 ER - TY - GEN A1 - Howell, Armin A1 - Tucker, Colin A1 - Grote, Ed A1 - Veste, Maik A1 - Belnap, Jayne A1 - Kast, Gerhard A1 - Weber, Bettina A1 - Reed, Sasha C. T1 - Manufacturing Simple and Inexpensive Soil Surface Temperature and Gravimetric Water Content Sensors T2 - Journal of Visualized Experiments N2 - Quantifying temperature and moisture at the soil surface is essential for understanding how soil surface biota responds to changes in its environment. However, at the soil surface these variables are highly dynamic and standard sensors do not explicitly measure temperature or moisture in the upper few millimeters of the soil profile. This manuscript describes methods for manufacturing simple, inexpensive sensors that simultaneously measure the temperature and moisture of the upper 5 mm of the soil surface. In addition to sensor construction, steps for quality control, as well as for calibration for various substrates, are explained. The sensors incorporate a Type E thermocouple to measure temperature and assess soil moisture by measuring the resistance between two gold-plated metal probes at the end of the sensor at a depth of 5 mm. The methods presented here can be altered to customize probes for different depths or substrates. These sensors have been effective in a variety of environments and have endured months of heavy rains in tropical forests as well as intense solar radiation in deserts of the southwestern U.S. Results demonstrate the effectiveness of these sensors for evaluating warming, drying, and freezing of the soil surface in a global change experiment. Y1 - 2019 U6 - https://doi.org/10.3791/60308 SN - 1940-087X VL - 154 ER -