TY - GEN A1 - Bendix, Jörg A1 - Aguire, Nicolay A1 - Beck, Erwin A1 - Bräuning, Achim A1 - Brandl, Roland A1 - Breuer, Lutz A1 - Böhning‑Gaese, Katrin A1 - Paula, Mateus Dantas de A1 - Hickler, Thomas A1 - Homeier, Jürgen A1 - Inclan, Diego A1 - Leuschner, Christoph A1 - Neuschulz, Eike L. A1 - Schleuning, Matthias A1 - Suarez, Juan P. A1 - Trachte, Katja A1 - Wilcke, Wolfgang A1 - Windhorst, David A1 - Farwig, Nina T1 - A research framework for projecting ecosystem change in highly diverse tropical mountain ecosystems T2 - Oecologia N2 - Tropical mountain ecosystems are threatened by climate and land-use changes. Their diversity and complexity make projections how they respond to environmental changes challenging. A suitable way are trait-based approaches, by distinguishing between response traits that determine the resistance of species to environmental changes and effect traits that are relevant for species' interactions, biotic processes, and ecosystem functions. The combination of those approaches with land surface models (LSM) linking the functional community composition to ecosystem functions provides new ways to project the response of ecosystems to environmental changes. With the interdisciplinary project RESPECT, we propose a research framework that uses a trait-based response-effect-framework (REF) to quantify relationships between abiotic conditions, the diversity of functional traits in communities, and associated biotic processes, informing a biodiversity-LSM. We apply the framework to a megadiverse tropical mountain forest. We use a plot design along an elevation and a land-use gradient to collect data on abiotic drivers, functional traits, and biotic processes. We integrate these data to build the biodiversity-LSM and illustrate how to test the model. REF results show that aboveground biomass production is not directly related to changing climatic conditions, but indirectly through associated changes in functional traits. Herbivory is directly related to changing abiotic conditions. The biodiversity-LSM informed by local functional trait and soil data improved the simulation of biomass production substantially. We conclude that local data, also derived from previous projects (platform Ecuador), are key elements of the research framework. We specify essential datasets to apply this framework to other mountain ecosystems. KW - Biodiversity-land surface model KW - Functional traits KW - High mountains KW - Research framework KW - Response-effect-framework Y1 - 2021 U6 - https://doi.org/10.1007/s00442-021-04852-8 SN - 0029-8549 SN - 1432-1939 VL - 195 IS - 3 SP - 589 EP - 600 ER - TY - CHAP A1 - Breuer, Lutz A1 - Exbrayat, Jean-François A1 - Plesca, Ina A1 - Buytaert, Wouter A1 - Ehmann, Theresa A1 - Peters, Thorsten A1 - Timbe, Edison A1 - Trachte, Katja A1 - Windhorst, David T1 - Global Climate Change Impacts on Local Climate and Hydrology T2 - Ecosystem Services, Biodiversity and Environmental Change in a Tropical Mountain Ecosystem of South Ecuador N2 - An interdisciplinary research unit consisting of 30 teams in the natural, economic and social sciences analyzed biodiversity and ecosystem services of a mountain rainforest ecosystem in the hotspot of the tropical Andes, with special reference to past, current and future environmental changes. The group assessed ecosystem services using data from ecological field and scenario-driven model experiments, and with the help of comparative field surveys of the natural forest and its anthropogenic replacement system for agriculture. The book offers insights into the impacts of environmental change on various service categories mentioned in the Millennium Ecosystem Assessment (2005): cultural, regulating, supporting and provisioning ecosystem services. Examples focus on biodiversity of plants and animals including trophic networks, and abiotic/biotic parameters such as soils, regional climate, water, nutrient and sediment cycles. The types of threats considered include land use and climate changes, as well as atmospheric fertilization. In terms of regulating and provisioning services, the emphasis is primarily on water regulation and supply as well as climate regulation and carbon sequestration. With regard to provisioning services, the synthesis of the book provides science-based recommendations for a sustainable land use portfolio including several options such as forestry, pasture management and the practices of indigenous peoples. In closing, the authors show how they integrated the local society by pursuing capacity building in compliance with the CBD-ABS (Convention on Biological Diversity - Access and Benefit Sharing), in the form of education and knowledge transfer for application. Y1 - 2013 SN - 978-3-642-38137-9 U6 - https://doi.org/10.1007/978-3-642-38137-9_19 SP - 265 EP - 274 PB - Springer-Verlag GmbH CY - Berlin [u.a.] ET - 1 ER - TY - GEN A1 - Limberger, Oliver A1 - Homeier, Jürgen A1 - Farwig, Nina A1 - Pucha-Cofrep, Franz A1 - Fries, Andreas A1 - Leuschner, Christoph A1 - Trachte, Katja A1 - Bendix, Jörg T1 - Classification of Tree Functional Types in a Megadiverse Tropical Mountain Forest from Leaf Optical Metrics and Functional Traits for Two Related Ecosystem Functions T2 - Forests N2 - Few plant functional types (PFTs) with fixed average traits are used in land surface models (LSMs) to consider feedback between vegetation and the changing atmosphere. It is uncertain if highly diverse vegetation requires more local PFTs. Here, we analyzed how 52 tree species of a megadiverse mountain rain forest separate into local tree functional types (TFTs) for two functions: biomass production and solar radiation partitioning. We derived optical trait indicators (OTIs) by relating leaf optical metrics and functional traits through factor analysis. We distinguished four OTIs explaining 38%, 21%, 15%, and 12% of the variance, of which two were considered important for biomass production and four for solar radiation partitioning. The clustering of species-specific OTI values resulted in seven and eight TFTs for the two functions, respectively. The first TFT ensemble (P-TFTs) represented a transition from low to high productive types. The P-TFT were separated with a fair average silhouette width of 0.41 and differed markedly in their main trait related to productivity, Specific Leaf Area (SLA), in a range between 43.6 to 128.2 (cm2/g). The second delineates low and high reflective types (E-TFTs), were subdivided by different levels of visible (VIS) and near-infrared (NIR) albedo. The E-TFTs were separated with an average silhouette width of 0.28 and primarily defined by their VIS/NIR albedo. The eight TFT revealed an especially pronounced range in NIR reflectance of 5.9% (VIS 2.8%), which is important for ecosystem radiation partitioning. Both TFT sets were grouped along elevation, modified by local edaphic gradients and species-specific traits. The VIS and NIR albedo were related to altitude and structural leaf traits (SLA), with NIR albedo showing more complex associations with biochemical traits and leaf water. The TFTs will support LSM simulations used to analyze the functioning of mountain rainforests under climate change. KW - ecosystem productivity KW - energy fluxes KW - leaf hyperspectra KW - functional traits KW - tree functional types KW - tropical forest Y1 - 2021 U6 - https://doi.org/10.3390/f12050649 SN - 1999-4907 VL - 12 IS - 5 ER - TY - GEN A1 - Knerr, Isabel A1 - Trachte, Katja A1 - Egli, Sebastian A1 - Barth, Johannes A. C. A1 - Bräuning, Achim A1 - Garel, Emilie A1 - Häusser, Martin A1 - Huneau, Frédéric A1 - Juhlke, Tobias R. A1 - Santoni, Sébastien A1 - Szymczak, Sonja A1 - Geldern, Robert van A1 - Bendix, Jörg T1 - Fog - low stratus (FLS) regimes on Corsica with wind and PBLH as key drivers T2 - Atmospheric Research N2 - The French Mediterranean island of Corsica is already today confronted with a clear tendency towards water shortage, leading not only to socio-economical, but also to ecological problems. A potential, but not very widespread source of water is the presence of near-ground clouds, mostly fog. In this study, we investigate fog-low stratus (FLS) frequencies in Corsica, derived from a data set of Meteosat Second Generation SEVIRI, whereby a distinction between fog and low stratus is hardly feasible using remote sensing data. The FLS frequency was studied with respect to its interaction with distinct locally-generated wind and its dependence on the planetary boundary layer height (PBLH) obtained by ERA5 reanalysis (the fifth generation of the European Centre for Medium-Range Weather Forecasts, ECMWF). Results show that radiation FLS is formed in coastal areas at sunrise, with low PBLH. On the other hand, in the interior of the island at sunset, a maximum of advection FLS is formed, fostered by locally-generated and related transport of moisture. On the east side of the island, FLS frequency is lower throughout the year due to frequent lee situations. This situation is reinforced by reduced synoptic moisture transport by westerly winds, so that westerly exposed slopes benefit from moisture input by FLS formation. KW - Corsica KW - Mediterranean KW - Fog Low Stratus KW - Meteosat Second Generation (MSG) KW - Planetary Boundary Layer KW - Locally-generated wind Y1 - 2021 U6 - https://doi.org/10.1016/j.atmosres.2021.105731 SN - 0169-8095 VL - 261 ER - TY - CHAP A1 - Trachte, Katja A1 - Ahmadpour, Somayeh T1 - Europe and the Middle East T2 - Regional Climates Y1 - 2024 U6 - https://doi.org/10.1175/2024BAMSStateoftheClimate_Chapter7.1 VL - 105 (2024) IS - 8 SP - 371 EP - 484 PB - American Meteoroligal Society ER - TY - GEN A1 - Trachte, Katja T1 - Recent progress in atmospheric modeling over the Andes – part II: projected changes and modeling challenges T2 - Sec. Atmospheric Science Y1 - 2024 U6 - https://doi.org/10.3389/feart.2024.1427837 VL - 12 (2024) SP - 1 EP - 21 PB - Frontiers in Earth Science ER - TY - GEN A1 - Trachte, Katja T1 - Recent progress in atmospheric modeling over the Andes – part I: review of atmospheric processes T2 - Atmospheric Science Y1 - 2024 U6 - https://doi.org/10.3389/feart.2024.1427783 VL - 12 (2024) SP - 1 EP - 23 PB - Frontiers in Earth Science ER - TY - JOUR A1 - Ahmed, Rezwan A1 - Zafor, Md. Abu A1 - Trachte, Katja T1 - Land-use and land-cover changes in Cottbus City and Spree-Neisse District, Germany, in the last two decades: a study using remote sensing data and Google Earth Engine JF - Remote Sensing N2 - Regular detection of land-use and land-cover (LULC) changes with high accuracy is necessary for natural resources management and sustainable urban planning. The produced LULC maps from Google Earth Engine (GEE) also illustrate the transformation of the LULC for the respective landscape over time. The selected study area, Cottbus City and the Spree-Neisse district in northeastern Germany, has undergone significant development over the past decades due to various factors, including urbanization and industrialization; also, the landscape has been converted in some areas for post-mining activities. Detection of LULC changes that have taken place over the last few decades thus plays a vital role in quantifying the impact of these factors while improving the knowledge of these developments and supporting the city planners or urban management officials before implementing further long-term development initiatives for the future. Therefore, the study aims to (i) detect LULC changes for the time slices 2002 and 2022, testing machine learning (ML) algorithms in supervised and unsupervised classification for Landsat satellite imageries, and (ii) validate the newly produced LULC maps with the available regional database (RDB) from the federal and state statistical offices, Germany, and the Dynamic World (DW) near real-time 10 m global LULC data set powered by artificial intelligence (AI). The results of the Random Forest (RF) and the Smilecart classifiers of supervised classification using Landsat 9 OLI-2/TIRS-2 in 2022 demonstrated a validation accuracy of 88% for both, with Kappa Index (KI) of 83% and 84%, respectively. Moreover, the Training Overall Accuracy (TOA) was 100% for both years. The wekaKMeans cluster of the unsupervised classification also illustrated a similar transformation pattern in the LULC maps. Overall, the produced LULC maps offered an improved representation of the selected region’s various land-cover classes (i.e., vegetation, waterbodies, built areas, and bare ground) in the last two decades (20022 to 2022). Y1 - 2024 U6 - https://doi.org/10.3390/rs16152773 SN - 2072-4292 VL - 16 IS - 15 SP - 1 EP - 16 PB - MDPI AG ET - 2nd edition ER - TY - GEN A1 - Fenner, Daniel A1 - Christen, Andreas A1 - Grimmond, Sue A1 - Meier, Fred A1 - Morrison, William A1 - Zeeman, Matthias A1 - Barlow, Janet A1 - Birkmann, Jörn A1 - Blunn, Lewis A1 - Chrysoulakis, Nektarios A1 - Clements, Matthew A1 - Glazer, Russell A1 - Hertwig, Denise A1 - Kotthaus, Simone A1 - König, Kai A1 - Looschelders, Dana A1 - Mitraka, Zina A1 - Poursanidis, Dimitris A1 - Tsirantonakis, Dimitris A1 - Bechtel, Benjamin A1 - Benjamin, Kit A1 - Beyrich, Frank A1 - Briegel, Ferdinand A1 - Feigel, Gregor A1 - Gertsen, Carlotta A1 - Iqbal, Nimra A1 - Kittner, Jonas A1 - Lean, Humphrey A1 - Liu, Yiqing A1 - Luo, Zhiwen A1 - McGrory, Megan A1 - Metzger, Swen A1 - Paskin, Matthew A1 - Ravan, Marvin A1 - Ruhtz, Thomas A1 - Saunders, Bethany A1 - Scherer, Dieter A1 - Smith, Stefan Thor A1 - Stretton, Megan A1 - Trachte, Katja A1 - Van Hove, Melania T1 - urbisphere-Berlin campaign: investigating multi-scale urban impacts on the atmospheric boundary layer T2 - Bulletin of the American Meteorological Society N2 - For next-generation weather and climate numerical models to resolve cities, both higher spatial resolution and sub-grid parameterizations of urban canopy-atmosphere processes are required. Key is to better understand intra-urban variability and urban-rural differences in atmospheric boundary layer (ABL) dynamics. This includes upwind-downwind effects due to cities’ influences on the atmosphere beyond their boundaries. To address these aspects a network of >25 ground-based remote-sensing sites was designed for the Berlin region (Germany), considering city form, function, and typical weather conditions. This allows investigation of how different urban densities and human activities impact ABL dynamics. As part of the interdisciplinary European Research Council Grant urbisphere, the network was operated from Autumn 2021 to Autumn 2022. Here we provide an overview of the scientific aims, campaign setup, and results from two days, highlighting multi-scale urban impacts on the atmosphere in combination with high-resolution numerical modeling at 100 m grid-spacing. During a spring day, the analyzes show systematic upwind-city-downwind effects in ABL heights, largely driven by urban-rural differences in surface heat fluxes. During a heatwave day, ABL height is remarkably deep, yet spatial differences in ABL heights are less pronounced due to overall dry soil conditions, resulting in similar observed surface heat fluxes. Our modeling results provide further insights into ABL characteristics not resolved by the observation network, highlighting synergies between both approaches. Our data and findings will support modeling to help deliver services to a wider community from citizens to those managing health, energy, transport, land-use and other city infrastructure and operations. Y1 - 2024 U6 - https://doi.org/10.1175/BAMS-D-23-0030.1 SN - 0003-0007 SN - 1520-0477 VL - 105 PB - American Meteorological Society ER - TY - GEN A1 - Häusser, Martin A1 - Aryal, Sugam A1 - Barth, Johannes A. C. A1 - Bendix, Jörg A1 - Garel, Emilie A1 - Geldern, Robert van A1 - Huneau, Frédéric A1 - Juhlke, Tobias R. A1 - Knerr, Isabel A1 - Santoni, Sébastien A1 - Szymczak, Sonja A1 - Trachte, Katja A1 - Bräuning, Achim T1 - Xylem formation patterns from Mediterranean to subalpine climate conditions reveal high growth plasticity of pine species on Corsica T2 - Trees N2 - Investigating seasonal wood formation is crucial to understand tree growth responses to climate impact. The present study quantifies the variability of xylogenesis along an elevation gradient on the Mediterranean island of Corsica, where two native pine species (Pinus nigra Arnold ssp. laricio Maire and Pinus pinaster Aiton) grow from the upper tree line to sea level, partly in sympatry. We extracted microcores from 35 trees at 5 sites along an East–West transect from the coasts (10 m asl) to the island's central mountain ridge (1600 m asl) during bi-weekly sampling campaigns between 2017 and 2019. We applied generalised additive models to detect radial growth differences in elevation and species along with minimum temperatures for growth initiation. We found that trees in low elevations experienced over 2 months longer growth periods with higher maximum growth rates than in high elevations. The results show a 1-month delay for the beginning of tracheid formation between the low, mid and high-elevation belts but comparable timing for its termination. At the sites where both species co-occur, P. nigra accumulates more radial cells in a shorter time than P. pinaster. Trees at the two contrasting coastal sites have similar growth period lengths, but exhibit a time shift of over a month. Minimum temperatures around growth initiation vary between 3.1 °C for P. nigra and 9.9 °C for P. pinaster. These findings emphasise the high plasticity in the growth behaviour of one of the most widespread tree genera in Mediterranean and temperate zones. KW - Generalised additive models (GAM) KW - Corsican black pine KW - Maritime pine KW - Cambial dynamics KW - Xylogenesis KW - Mediterranean Y1 - 2023 U6 - https://doi.org/10.1007/s00468-023-02402-8 SN - 0931-1890 SN - 1432-2285 VL - 37 IS - 4 SP - 1027 EP - 1039 PB - Springer Berlin Heidelberg ER - TY - GEN A1 - Murkute, Charuta A1 - Sayeed, Mostafa A1 - Pucha-Cofrep, Franz A1 - Carrillo-Rojas, Galo A1 - Homeier, Jürgen A1 - Limberger, Oliver A1 - Fries, Andreas A1 - Bendix, Jörg A1 - Trachte, Katja T1 - Turbulent energy and carbon fluxes in an Andean Montane Forest—energy balance and heat storage T2 - Forests N2 - High mountain rainforests are vital in the global energy and carbon cycle. Understanding the exchange of energy and carbon plays an important role in reflecting responses to climate change. In this study, an eddy covariance (EC) measurement system installed in the high Andean Mountains of southern Ecuador was used. As EC measurements are affected by heterogeneous topography and the vegetation height, the main objective was to estimate the effect of the sloped terrain and the forest on the turbulent energy and carbon fluxes considering the energy balance closure (EBC) and the heat storage. The results showed that the performance of the EBC was generally good and estimated it to be 79.5%. This could be improved when the heat storage effect was considered. Based on the variability of the residuals in the diel, modifications in the imbalances were highlighted. Particularly, during daytime, the residuals were largest (56.9 W/m 2 on average), with a clear overestimation. At nighttime, mean imbalances were rather weak (6.5 W/m 2 ) and mostly positive while strongest underestimations developed in the transition period to morning hours (down to −100 W/m 2 ). With respect to the Monin–Obukhov stability parameter ((z − d)/L) and the friction velocity (u*), it was revealed that the largest overestimations evolved in weak unstable and very stable conditions associated with large u* values. In contrast, underestimation was related to very unstable conditions. The estimated carbon fluxes were independently modelled with a non-linear regression using a light-response relationship and reached a good performance value (R 2 = 0.51). All fluxes were additionally examined in the annual course to estimate whether both the energy and carbon fluxes resembled the microclimatological conditions of the study site. This unique study demonstrated that EC measurements provide valuable insights into land-surface–atmosphere interactions and contribute to our understanding of energy and carbon exchanges. Moreover, the flux data provide an important basis to validate coupled atmosphere ecosystem models. KW - energy balance closure KW - heat storage KW - carbon fluxes KW - eddy covariance KW - Andes Mountains Y1 - 2024 U6 - https://doi.org/10.3390/f15101828 SN - 1999-4907 VL - 15 IS - 10 PB - MDPI ER - TY - GEN A1 - Trachte, Katja A1 - Raffelsbauer, Volker T1 - Trees with anisohydric behavior as main drivers of nocturnal evapotranspiration in a tropical mountain rainforest T2 - PLoS ONE Y1 - 2023 U6 - https://doi.org/10.1371/journal.pone.0282397 VL - 18 (3) SP - 1 EP - 21 ER - TY - GEN A1 - Grigusova, Paulina A1 - Limberger, Oliver A1 - Murkute, Charuta A1 - Pucha-Cofrep, Franz A1 - Gonzalez-Jaramillo, Victor Hugo A1 - Fries, Andreas A1 - Windhorst, David A1 - Breuer, Lutz A1 - Dantas de Paula, Mateus A1 - Hickler, Thomas A1 - Trachte, Katja A1 - Bendix, Jörg T1 - Radiation partitioning in a cloud-rich tropical mountain rain forest of the S-Ecuadorian Andes for use in plot-based land surface modelling T2 - Dynamics of atmospheres and oceans : planetary fluid, climatic and biogeochemical systems N2 - Understanding the partitioning of downward shortwave radiation into direct and diffuse components is essential for modeling ecosystem energy fluxes. Accurate partitioning functions are critical for land surface models (LSMs) coupled with climate models, yet these functions often depend on regional cloud and aerosol conditions. While data for developing semi-empirical partitioning functions are abundant in mid-latitudes, their performance in tropical regions, particularly in the high Andes, remains poorly understood due to scarce ground-based measurements. This study analyzed a unique dataset of shortwave radiation components from a tropical mountain rainforest (MRF) in southern Ecuador, developing and testing a locally adapted partitioning function using Random Forest Regression. The model achieved high accuracy in predicting the percentage of diffuse radiation (%Dif; R²=0.95, RMSE = 5.33, MAE = 3.74) and absolute diffuse radiation (R²=0.99, RMSE = 5.30, MAE = 14). When applied to simulate upward shortwave radiation, the model outperformed commonly used partitioning functions achieving the lowest RMSE (8.62) and MAE (5.82) while matching the highest R² (0.97). These results underscore the importance of regionally adapted radiation partitioning functions for improving LSM performance, particularly in complex tropical environments. The adapted LSM will be further utilized for studies on heat fluxes and carbon sequestration. Y1 - 2025 U6 - https://doi.org/10.1016/j.dynatmoce.2025.101553 SN - 0377-0265 VL - 110 SP - 1 EP - 16 PB - Elsevier CY - Amsterdam ER - TY - GEN A1 - Bendix, Jörg A1 - Limburger, Oliver A1 - Breuer, Lutz A1 - Dantas de Paula, Mateus A1 - Fries, Andreas A1 - Gonzalez-Jaramillo, Victor Hugo A1 - Grigusova, Paulina A1 - Hickler, Thomas A1 - Murkute, Charuta A1 - Pucha-Cofrep, Franz A1 - Trachte, Katja A1 - Windhorst, David T1 - Simulation of latent heat flux over a high altitude pasture in the tropical Andes with a coupled land surface framework T2 - The science of the total environment N2 - Latent heat flux is a central element of land-atmosphere interactions under climate change. Knowledge is particularly poor in the biodiversity hotspot of the Andes, where heat flux measurements using eddy covariance stations are scarce and land surface models (LSMs) often oversimplify the complexity of the ecosystems. The main objective of this study is to perform latent heat flux simulations for the tropical South Eastern (SE) Ecuadorian Andes using a coupled LSM framework, and to test the performance with heat flux and soil moisture data collected from a tropical high-altitude pasture. Prior to testing, we applied multi-criteria model calibration of sensitive model parameters, focusing on improving simulated soil water conditions and radiation fluxes as a prerequisite for proper heat flux simulations. The most sensitive parameters to improve soil moisture and radiation flux simulations were soil porosity, saturated hydraulic conductivity, leaf area index, soil colour and NIR (Near Infrared) leaf optical properties. The best calibrated model run showed a very good performance for half-hourly latent heat flux simulations with an R² of 0.8 and an RMSE of 34.0 W m⁻², outperforming simulations with uncalibrated and uncoupled LSM simulations in comparable areas. The slight overall overestimation in the simulated latent heat flux can be related to (i) simulation uncertainties in the canopy heat budget, (ii) an imbalance in the observed flux data and (iii) slight overestimations in the simulated soil moisture. Although our study focuses on latent heat fluxes and their relation to simulated radiation fluxes and soil moisture, model outputs of sensible heat fluxes were also discussed. The systematic overestimation of sensible heat flux in the model seems to be mainly a result of overestimated canopy temperatures. The improved simulation for latent heat flux has a high translational potential to support land use strategies in the tropical Andes under climate change. Y1 - 2025 U6 - https://doi.org/10.1016/j.scitotenv.2025.179510 SN - 1879-1026 VL - 981 SP - 1 EP - 21 PB - Elsevier CY - Amsterdam ER - TY - GEN A1 - Limberger, Oliver A1 - Homeier, Jürgen A1 - Gonzalez-Jaramillo, Victor A1 - Fries, Andreas A1 - Murkute, Charuta A1 - Trachte, Katja A1 - Bendix, Jörg T1 - Foliar trait retrieval models based on hyperspectral satellite imagery perform well in a biodiversity hotspot of the SE Ecuadorian Andes T2 - International journal of remote sensing N2 - The determination of the spatial distribution of canopy traits is crucial for understanding the spatio-temporal dynamics of ecosystem functions, such as carbon sequestration, water and energy fluxes in tropical montane forests. Especially in remote areas such as the Andes of south-east Ecuador, remote sensing using satellites has been proven to provide valuable information on canopy traits. However, the performance of the multispectral models to date is limited. Here, we analyse the potential of DESIS (DLR Earth Sensing Imaging Spectrometer) hyperspectral surface reflectance data for the prediction of specific leaf area (SLA), foliar toughness, nitrogen (N) and phosphorus (P) content by calibrating a PLSR model for each foliar trait. Model validation showed a high explanation of variance (R2 : 0.78–0.92) and a low model error (mean-normalized RMSE: 8–13%) for all traits, showing an improved performance compared to models based on multispectral imagery and ancillary data within the same forest type. Hyperspectral models predicting foliar traits from individual tree crowns showed a lower performance for most traits, probably related to the difference in spatial resolution compared to this study. Given the high species richness of the Andean biodiversity hotspot and the complex topography, the high quality of the DESIS models is remarkable, considering that the multispectral models from the region require topographic predictors in addition to reflectances to achieve a good performance. The spatial trait maps generated by our models based on the reflectances only show clear relationships with terrain elevation. Thus, the hyperspectral trait maps from satellite orbit are capable of supporting large-scale ecological analyses between features, diversity and ecosystem functions. Y1 - 2025 U6 - https://doi.org/10.1080/01431161.2025.2511211 SN - 1366-5901 SP - 1 EP - 19 PB - Taylor & Francis CY - London ER - TY - GEN A1 - Saravia, Christian A1 - Trachte, Katja T1 - Spatiotemporal analysis of NH₃ emission sources and their relation to land use types in the Eastern German lowlands T2 - Atmosphere N2 - Ammonia (NH₃) emissions, which are key precursors of fine particulate matter, pose significant environmental challenges. This study investigated the spatiotemporal variations in NH₃ emissions across the eastern German lowlands from 2013 to 2022 using IASI-B satellite data. Five major Land Cover Classes (LCC) –tree, grassland, cropland, built-up areas, and water bodies– were analyzed. The results showed distinct diurnal variations, with nighttime NH₃ concentrations exceeding 2.0 × 10¹⁶ molecules cm⁻² in the peak months. Seasonal patterns indicated significant emissions in March (1.2 × 10¹⁶ molecules cm⁻²), April (1.1 × 10¹⁶ molecules cm⁻2), and August (9.6 × 10¹⁵ molecules cm⁻²), while the lowest concentrations occurred in September (0.6 × 10¹⁵ molecules cmv²). Persistent hotspots were identified in the northwestern region, where emissions peaked in spring (1.8 × 10¹⁶ molecules cm⁻²) and summer (1.3 × 10¹⁶ molecules cm⁻²), primarily due to agricultural activities. Over the study period, the annual NH₃ concentration peaked in 2015, 2018, and 2022. Using k-means clustering, three distinct emission zones were identified, with Cluster 3 showing the highest NH₃ emission values, particularly in urban centers, and agricultural zones were identified, covering less than 20% of the study area, where cropland predominates (8%). Meteorological factors significantly influenced NH₃ levels, with negative correlations obtained for precipitation, wind speed, and evaporation, while solar radiation, boundary layer height, and instantaneous moisture fluxes showed positive correlations. A case study from March 2022, employing the HYSPLIT trajectory model, confirmed that agricultural practices are the dominant NH₃ source, with emissions reaching 3.2 × 10¹⁶ molecules cm⁻² in hotspot regions. Y1 - 2025 U6 - https://doi.org/10.3390/atmos16030346 SN - 2073-4433 VL - 16 SP - 1 EP - 21 PB - MDPI CY - Basel ER - TY - GEN A1 - Ahmadpour, Somayeh A1 - Bayzidi, Yasin A1 - Trachte, Katja T1 - Spatio-temporal patterns of evapotranspiration in the temperate Eastern German lowlands and its response to climate and land use change T2 - Theoretical and applied climatology N2 - Evapotranspiration (ET) is a key factor in the water and energy cycle, playing a critical role, especially in agricultural regions. The eastern German lowlands, with their continental climate, are one of the driest regions in Germany, yet agriculture is the dominant land use. This study investigates the spatio-temporal variability of ET and its response to climate and land use/land cover change (LUCC) using MODIS remote sensing products and in-situ measurements over the period 2000-2020. The results show a slight increase in the mean annual ET, with local increases of up to 7.2% in the southern and southeastern parts of Brandenburg. LUCC revealed a 22.2% decrease in grassland to cropland conversion, leading to a decline in ET of 21%, while conversion from grassland to cropland increased by 14.8%, resulting in a 10% increase in ET. The strongest relationship with ET was found for vapor pressure deficit (VPD), temperature (Temp), and relative humidity (RH), which contributed 25.2%, 30.9%, and 23.2%, respectively, to its total variability. In addition to atmospheric factors soil moisture (SM) also contributed 17.7% to ET, but only in grassland. LUCC played a minor role as 22% of the study area was under conversion. Consequently, climate change, represented by the temporal change of the climatic factors, was identified as the dominant driver of ET in the study area, accounting for 97% of its variability. Accordingly, these findings underscore the importance of Temp, RH, and SM in agricultural and water resource management. Y1 - 2025 U6 - https://doi.org/10.1007/s00704-025-05529-5 SN - 1434-4483 VL - 156 SP - 1 EP - 19 PB - Springer ER - TY - GEN A1 - Laux, Patrick A1 - Feldmann, David A1 - Marra, Francesco A1 - Feldmann, Hendrik A1 - Kunstmann, Harald A1 - Trachte, Katja A1 - Peleg, Nadav T1 - Future precipitation extremes and urban flood risk assessment using a non-stationary and convection-permitting climate-hydrodynamic modeling framework T2 - Journal of hydrology N2 - Urban planners and engineers rely on historical climate data to plan and design flood protection infrastructure that should withstand extreme flooding events with 1% annual exceedance probability (the 100-year flood). Here, we examine how hourly precipitation extremes are expected to change as temperatures rise and how this will affect urban flooding. The changes to short-duration rainfall extremes, often insufficiently considered in practice, are addressed utilizing a new temperature conditional extreme precipitation scaling approach and a novel regional climate convection-permitting model ensemble for +2 °C and +3 °C global warming scenarios. Based on hydrodynamic modeling, we estimate how future precipitation extremes translate into flood risks in two pre-alpine communes in Germany. Ignoring the impacts of climate change may lead to severe underestimations of flood risks. The +3 °C global warming scenario translates into an increase of 60% of affected buildings by the highest flood risk category (water level of 1 m and above). The increase in flow intensities will be greater in the commune characterized by steeper terrain. The results suggest that recently planned or implemented infrastructure projects may not be adequately equipped to cope with the anticipated effects of climate change in the coming decades. KW - Urban pluvial flooding KW - Non-stationary precipitation extremes KW - Clausius-Clapeyron KW - TENAX KW - Convection-permitting models KW - Hydrodynamic modeling KW - Flood hazard Y1 - 2025 U6 - https://doi.org/10.1016/j.jhydrol.2025.133607 SN - 1879-2707 VL - 661, Part B SP - 1 EP - 14 PB - Elsevier CY - Amsterdam ER - TY - GEN A1 - Gerwin, Werner A1 - Raab, Thomas A1 - Hinz, Christoph A1 - Letmathe, Peter A1 - Leuchner, Michael A1 - Roß-Nickoll, Martina A1 - Rüde, Thomas A1 - Trachte, Katja A1 - Wätzold, Frank A1 - Lehmkuhl, Frank T1 - Perspectives of lignite post‑mining landscapes under changing environmental conditions: what can we learn from a comparison between the Rhenish and Lusatian region in Germany? T2 - Environmental Sciences Europe N2 - Background The decision of the German federal government to cease lignite mining until 2038 or—if possible— already earlier until 2030, will cause manifold transition processes in the remaining lignite mining districts of Germany. The two largest districts are located in geographically opposite regions: The Rhineland in the western part and Lusatia in the east of Germany. As particularly these two mining districts will experience severe changes in their socioeconomic as well environmental conditions, the federal government has adopted comprehensive economic support measures. However, the environmental changes will also cause altered ecosystem functions and services to be provided by the future post-mining landscapes. Results In this paper, the two main lignite-producing regions of Germany are compared with regard to their natural and cultural settings. The economic situation and its history are reflected and differences are outlined. Part of the disparities in the cultural development can be explained by very different natural conditions, especially edaphic factors and climatic situation. Because of dissimilar geological settings, different mining technologies were developed and are in use in the two regions with distinct effects on the resulting post-mining landscapes. Conclusion The long-standing and manifold lignite mining activities have radically restructured the landscapes in Lusatia and the Rhineland. With the ongoing decline of the mining industry and its complete cessation, presumably within the next decade, both regions will alter their faces significantly. These changes offer both challenges but also opportunities with respect to the post-mining landscapes and their ecosystem services they are going to provide. The prerequisites for a positive socioeconomic development and for sustainable land-use concepts that also consider ecological aspects are different for both regions. However, or especially because of these differences, the knowledge exchange and experience transfer between both mining regions are pivotal for the success of this extensive transformation process. KW - Lignite mining KW - Ecosystem services KW - Post-mining landscapes KW - Transformation processes Y1 - 2023 U6 - https://doi.org/10.1186/s12302-023-00738-z SN - 2190-4715 VL - 35 ER - TY - GEN A1 - Lehmkuhl, Frank A1 - Gerwin, Werner A1 - Raab, Thomas A1 - Birkhofer, Klaus A1 - Hinz, Christoph A1 - Letmathe, Peter A1 - Leuchner, Michael A1 - Roß-Nickoll, Martina A1 - Rüde, Thomas R. A1 - Trachte, Katja A1 - Wätzold, Frank T1 - Perspectives for the lignite post-mining landscapes of the lignite mining landscapes under changing environmental conditions - what can we learn from a comparison between the Rhenish and the Lusatian regions in Germany? : EGU General Assembly 2024, Vienna, Austria & Online | 14–19 April 2024 N2 - The German government's decision to phase out lignite mining by 2038 or earlier, as recently 2030 has been agreed for the Rhineland, will trigger a number of transition processes in Germany's remaining lignite mining areas. The two largest lignite mining areas are located in geographically different regions: Rhineland in the west and Lusatia in the east. As the socio-economic and environmental conditions in these two mining areas are set to change dramatically, the German government has adopted extensive economic support measures. However, the environmental changes will also lead to changes in the ecosystem functions and services provided by the future post-mining landscapes. Gerwin et al. (2023) compare the two main lignite producing regions of Germany in terms of their natural and cultural environments. The economic situation and its history are reflected and differences are outlined. Part of the differences in cultural development can be explained by the natural conditions, especially the edaphic factors and the climatic situation. Because of the specific geological settings, tailored mining technologies were developed and used in the two regions, with different effects on the resulting post-mining landscapes. We conclude that the landscapes of Lusatia and the Rhineland have been radically restructured by the long and varied history of lignite mining. Both regions will change significantly as the mining industry continues to decline and is expected to cease altogether within the next decade. These changes in the post-mining landscapes and the ecosystem services will provide both challenges and opportunities. The preconditions for positive socio-economic development and for sustainable land use concepts that also consider ecological aspects are different for the two regions. The exchange of knowledge and experience between the two mining regions is crucial to the success of this major transformation process, despite, or perhaps because of, these differences. Gerwin, W., Raab, T., Birkhofer, K., Hinz, C., Letmathe, P., Leuchner, M., Roß-Nickoll, M., Rüde, T., Trachte, K., Wätzold, F., Lehmkuhl, F. (2023): Perspectives of lignite post-mining landscapes under changing environmental conditions: what can we learn from a comparison between the Rhenish and Lusatian region in Germany? Environmental Sciences Europe 35:36. https://doi.org/10.1186/s12302-023-00738-z Y1 - 2024 U6 - https://doi.org/10.5194/egusphere-egu24-2791 PB - Copernicus GmbH ER - TY - GEN A1 - Veste, Maik A1 - Grey, Kerry-Anne A1 - Gottschalk, Nadine A1 - Trachte, Katja A1 - Midgley, Guy F. T1 - Can shelterbelt trees reduce evapotranspiration and ecophysiological stress in irrigated vineyards and citrus orchards? A transcontinental experiment in the Western Cape, South Africa and Lower Lusatia, Germany T2 - Landscape 2021 - Diversity for Sustainable and Resilient Agriculture N2 - In the context of ongoing climate change and increasing population, there is an urgent need to optimize the water consumption of surface and groundwater in agricultural production. In recent years, intensive irrigated viticulture and horticulture have faced increasing demand pressure in many water-limited areas including the Western Cape Province in South Africa. Shelterbelts of trees are often used to reduce wind speed and water demands as an eco-engineering measure directly influencing soil evaporation and crop transpiration. Objectives are (i) to evaluate the extent of impacts of wind speed from shelterbelts at canopy level in citrus orchards and vineyards (ii) to assess the wind effects at leaf level including leaf temperature and related ecophysiological performance in irrigated vineyards. Y1 - 2021 U6 - https://doi.org/10.13140/RG.2.2.34333.03043 ER -