Team doc.funds AlpsChange: v.l.n.r..: Anja Hörger, Jörg Robl, Jan Habel, Martin Knoll, Jana Petermann, Christoph von Hagke, Jonas Eberle, Andreas Lang, Andreas Tribsch, Stefan Dötterl, Beate Apfelbeck, Wolfgang Meier, Karin Gross; Fachbereiche Umwelt und Biodiversität und Geschichte, Paris Lodron Universität Salzburg;
The Alps harbour high geo- and biodiversity and are highly impacted by past, present and future environmental changes. In our new doctoral program AlpsChange we join forces to develop a state-of-the-art interdisciplinary research and training agenda. With a consortium involving scientists across a wide range of disciplines including geology, geomorphology, ecological and evolutionary botany and zoology, as well as history, we ask: (1) What are the effects of environmental perturbations on geo- and biosystems, and how do changes in one system translate to the other system? (2) What are the feedback loops between geo- and biosystems? (3) Which past and future dynamics can be inferred when integrating data from geoscience, bioscience and history?
Our training program includes novel interdisciplinary educational offers and will facilitate the training of open-minded scientists fully aware of interactions between geo- and biosystems across a wide range of temporal and spatial scales. The new generation of experts will thus be able to bridge disciplinary gaps between the geo- and biosciences and to establish links to social sciences – skills that are essential to address the challenges caused by the ongoing climate and biodiversity crises.
Bedrock type has strong effects on the chemical and physical properties of alpine soils. Common across the European Alps are siliceous and carbonate rocks on which acid or basic soils develop over time. Most rock-/ soil types are characterised by specific plant communities and in many plant lineages closely related species or subspecies / ecotypes occur uniquely for the bedrock type they grow on, a phenomenon called edaphic vicariance. So far, little is known to what extent bedrock type contributes to floral diversification in these plants, which subsequently may drive speciation. We also have little understanding how nutrient availability and rock weathering / soil-development change over time in response to plant presence. We use the insect-pollinated cushion plant Silene acaulis with its vicarious subspecies (S. a. longiscapa, calcicolous; S. a. exscapa, silicicolous) to determine (1) the extent to which previously described differences in floral morphology and potential differences in other floral traits (e.g. scent, nectar) between the subspecies are due to phenotypic plasticity in response to the different rock types / soils and / or due to genetic differentiation, and (2) how the soil develops over time in the presence of the plants and if the different subspecies affect soil chemistry in differing ways.
Plants and microorganisms are important agents in weathering processes and soil formation, however the underlying mechanisms are not understood in detail. In this project, we aim to investigate the reciprocal interplay between plants and their abiotic habitat by quantifying the direct and indirect impact of the local vegetation on soil chemistry. As a model, we will use metallophyte plants exhibiting different metal uptake strategies and hypothesize that these impact the chemical and microbial composition of their belowground environments differently thus causing differences in weathering and soil formation rates, which can be quantified to assess the plants’ contribution to these processes. We will base our studies at natural sites and in common garden settings and will measure reciprocal element fluxes between soil and plants using inductively coupled plasma mass spectrometry, quantify weathering rates of the parent bedrock via X-ray fluorescence spectrometry and scanning electron microscopy, assess the composition of the local soil microbiome via metabarcoding and identify chemical components involved in microbial enrichment and rock weathering using for example thermal desorption GC-MS. Our results will reveal effects organisms may have on their abiotic surroundings and will shed light on the dynamics occurring at the interface between bio- and geosphere during the succession of disturbed habitats.
Climate change will have dramatic effects on water regimes above and below the ground. Specialist organisms occur in groundwater and colonize spring systems which may harbour a mixture of regular and accidental subterranean species as well as above-ground dispersers (e.g. insects). Thus, spring communities can be seen as model metacommunities with limited dispersal between them. In addition, many springs have very specific abiotic conditions that may drive their community composition. For these reasons, communities in springs may be used as “biotic tracers” of hydrogeological patterns. We will investigate spring habitats to address the following research questions: 1) What are the determinants of community composition of springs? 2) Can organisms be used as natural tracers and help to determine catchment areas of springs? 3) How will communities change with rapid changes in water regimes in the future? In two model sites in the Alps, we will generate hydrogeological maps and conceptual flow models, measure physico-chemical field parameters, hydrochemical and isotope composition and discharge variations. Tracer tests will be carried out in karst areas, where appropriate and possible. The springs will be sampled for organisms including crustacean and aquatic insect species. Samples will be analysed for living organisms as well as eggs and resting stages to allow an assessment of potential dispersal of organisms through the aquifers.
Under a rapidly changing climate, mountains react with increased erosion rates and consequently formation of open rock fractures. While on the one hand, such fractures may result in geohazards such as rock falls, they may on the other hand form local habitats and micro-climatic niches. While their geometry has been studied in detail, their time evolution is challenging to constrain. Particularly, it is unknown how rapidly these fracture networks evolve under changing climate. This knowledge is however vital for determining how such fractures develop into geohazards or into micro-habitats. on Indeed, micro-habitat evolution may be used to determine fracture growth rates. In turn, it is important to assess how ecosystems can adjust to different rates of fracture propagation and consequently evolving micro-habitats. We hypothesize that fracture growth in dynamically changing mountains forms local habitats in which different species can find niches sheltering them from large-scale landscape changes. They form local bio-diversity hotspots. In turn, the degree of soil formation, the diversity of inhabiting species as well as the type of species present provide information on the time evolution of fracture growth.
Climate change in mountains alters ecological altitudinal regimes by shifting species distributions, changing community compositions, and disrupting ecosystem dynamics. Cool scree slopes, characterized by loose, rocky terrains, produce their own microclimate by allowing cold winter air to enter the voids between the clasts and releasing this air in summer. As global temperatures rise, these slopes provide cooler microhabitats that support species unable to thrive in warmer conditions. The significance of cool scree slopes lies in their ability to harbor unique ecosystems, including cold-adapted flora and fauna, which are increasingly vulnerable to climate change. These areas act as thermal refuges, buffering species from the heat stress associated with rising temperatures, and thus play a crucial role in maintaining biodiversity. We seek to quantify the regional occurrence and geomorphological characteristics of cool scree slopes, assess their microclimate at different selected locations, and interlink climatic and geomorphic conditions to the distribution and characteristics of plant and animal communities under a changing climate. The project combines remote-sensing analysis with field work in climatology, geomorphology and biology. Understanding the ecological importance of these habitats in a warming climate is essential for conservation strategies aimed at preserving species diversity in the face of climate-induced changes.
Field observations from alpine catchments suggest that climate change has triggered a morphological (hillslope and river dynamics) and biotic (vegetation cover) response. Changes in the coupled bio-geo-system are also detectable at the mountain range scale by remote sensing data that have been recorded for decades by various sensors with increasing spatial, spectral and temporal resolution. These data provide climatic variables as well as geological and biotic factors that make system changes observed at study sites also detectable at the mountain range scale. This project is about identifying and predicting landscape sensitivity in the Alps to climate change by computing past, present, and future changes based on field observations, remote sensing time series and climate model projections.Starting from local keys sites representing the drainage- and hillslope system, we will employ Google Earth Engine (GEE) and its wealth of freely available data characterising both biotic and abiotic factors. (1) Due to upscaling from catchment- to mountain range scale we will compute spatio-temporal gradients of biotic and abiotic factors across the Alps via GEE and the novel HPC facility at Salzburg University. (2) We will determine changes in the erosional potential of Alpine torrents based on climate variables recorded over the past decades and for future conditions as predicted by climate models. (3) We will work with supervised deep learning to detect hillslopes close to a critical state of failure considering both physical and biotic factors. (4) By synthesizing our results, we aim deriving the sensitivity of the landscape to climate change.
Climatic changes cause altitudinal and longitudinal shifts of species distribution and might thereby cause decoupling of interacting species. This project is focusing on the butterfly species Cupido minimus and its host plant Anthyllis vulneraria. The study aims to understand how climate warming affects the distribution of these species and their habitat, calcareous grasslands, considering geomorphological, climatic, and land-use conditions. The research questions include:
1. What are the current and future distributions of C. minimus, A. vulneraria, and their ecosystem? 2. How do butterfly morphology, gene expression, and host selection behavior, as well as floral scent and color vary along an altitudinal gradient, and are there signs of local adaptation? 3. How do these traits change under different temperatures in a standardized setting?
The approach involves modeling current and future distributions, conducting in-situ experiments by transplanting food plants and butterflies to different altitudes, and performing ex-situ experiments in climate chambers to simulate various climate change scenarios. The study will analyze changes in floral scents and their attractiveness to butterflies, as well as butterfly morphology, host selection behavior, and genetic expressions to evaluate potential responses to climate change.
Supervisor team: Bernhard Salcher, Jan Habel, Andreas Tribsch, Anja Hörger, Jonas Eberle, Jörg Robl, Beate A. Apfelbeck, Mathias Hopfinger
Alpine habitats react very differently to climatic change and human induced modifications of the landscape. This project focuses on Alpine peatlands to analyse effects of rapid climate change and anthropogenically induced impacts of land-use on species diversity and species community composition. Peatlands are particularly sensitive to record these effects and are important archives to determine climate and environmental change over time periods often exceeding 10.000 years. With increasing altitude, ecosystems tend to become more sensitive to any disturbance, but resilience may also be controlled by the substrate, i.e. the alpine mire type, which is strongly conditioned by past glacial processes. Effects and controlling factors will be integratively analysed in East Alpine peat bogs of different type and at different elevation zones. Changes will be analysed based on past, historic and current data on e.g. land use, biodiversity, and climate. This will for example allow to investigate the response of selected species groups or analyse species persistence and identify tipping points for vital environments. The research approach involves lab- and field- based methods like e.g. GIS-based analysis of historic data and high-resolution aerial imagery as well as field mapping focusing on variations in vegetation, arthropods, geology and hydrology. Subsurface data will be derived from e.g. geophysical surveying and drill-core analysis.
The Alps were almost fully glaciated during the Last Glacial Maximum (LGM) and alpine species have mainly survived in refugia at the Eastern and Southern Alpine margin. Biogeographical patterns of the Alpine biodiversity still today bear signatures as high endemism in marginal areas. We can expect that the late Pleistocene and Early Holocene with the dynamic climate (e.g, the climatically cold and dry Younger Dryas period) also had great impact on high altitude ecosystems. Whereas the formation and changes of lowland communities after the LGM is well understood we still lack knowledge (1) how alpine LGM and late glacial plant communities were composed and geographically structured; (2) how fast (sub-) alpine grassland and scrubland were able to re-establish after deglaciation; (3) how environmental changes during late Pleistocene and Early Holocene caused alpine biodiversity dynamics in detail. Paleoenvironmental modelling techniques and sedimentary archives in alpine environments will be used to unravel past and predict future dynamics of bio- and geodiversity. Ancient DNA analyses from lake sediments and from other archives (sedaDNA, like doline fillings, along mountain ridges, alpine fens and lakes, deposition sites potentially containing ancient DNA-archives). Meta-DNA-Barcoding will be applied for estimation of plant species identity and diversity over time in refugia / once glaciated areas along an E/W-Gradient. Such a detailed understanding of historical vegetation dynamics will be essential for accurate prediction of future dynamics of bio- and geodiversity in the Alps.
Deeply dissected gully systems and badland morphologies are common features on slopes in today tree covered upland areas. The project will test if these fossilised dendritic gully systems result from erosion processes occurring during Late medieval and Early modern times. At that time and to provide wood fuel for salt production and ore processing hillslopes were clear-cut leaving them highly vulnerable to rainfall erosion. The situation changed with the introduction of fossil fuels and tree growth stabilised the deeply eroded landscapes. To quantify landscape dynamics during this period historical, geomorphological, geochronological, and dendrochronological approaches will be utilized to link economic transformation and environmental dynamics. Key catchments will be identified for which historical data is easily available. Erosional landforms and their depositional records will be localised from high resolution LIDAR data and analysed by sediment analysis and shallow geophysics. Historical records of wood consumption (including spatial information from cadastral archives) will be collated, age-distributions of trees growing in and around the erosional landforms will be established, and sedimentary deposits will be quantified and dated using 14C, OSL, 210 Pb. Integrating the different strands of information will allow quantifying landscape stabilisation after the massive shift in fuel economy and provide reliable time scales for post-disturbance woodland-recovery.
