@phdthesis{Trappe2022, author = {Trappe, Julian}, title = {The influence of medieval building activity on relief development within the Spessart uplands, Germany. A sedimentological, geophysical and GIS-based approach at different castle and mining sites}, edition = {1. Auflage}, publisher = {W{\"u}rzburg University Press}, address = {W{\"u}rzburg}, isbn = {978-3-95826-184-6}, issn = {0510-9833}, doi = {10.25972/WUP-978-3-95826-185-3}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-261499}, school = {W{\"u}rzburg University Press}, pages = {XXI, 250}, year = {2022}, abstract = {In the Spessart, a low mountain range in central Germany, a feud during the Middle Ages led to the construction of numerous castles in this region. This study analyzes the mutual influence of (paleo-)relief development and medieval building activity using a geomorphological and geoarchaeological multimethod approach to expand the knowledge of human-environmental interactions during this time. For this purpose, GIS-based terrain analysis and geophysical measurements were conducted and combined with sedimentological information to create 1D-3D models of the subsurface and to assess knowledge of the landscape and relief evolution at various medieval castle and mining sites. The interpretation of all these data led to the answering of numerous site-specific questions on various geomorphological, geoarchaeological, geologic, and archaeological topics that have been explored in this work and have greatly increased our knowledge of each study site. In addition to these key contributions to the archaeological and geomorphological interpretation of individual study sites, a quantification of the anthropogenic influence on the relief development was conducted, a generalized model of the influence was derived, and new methodological and interpretative approaches were developed. Overall, this study links geomorphological/geological and (geo-)archaeological investigations at five medieval sites and delivers important information on human-environmental interactions within the Spessart and beyond.}, subject = {Geoarch{\"a}ologie}, language = {en} } @article{KleemannZamoraVillacisChiluisaetal.2022, author = {Kleemann, Janina and Zamora, Camilo and Villacis-Chiluisa, Alexandra Belen and Cuenca, Pablo and Koo, Hongmi and Noh, Jin Kyoung and F{\"u}rst, Christine and Thiel, Michael}, title = {Deforestation in continental Ecuador with a focus on protected areas}, series = {Land}, volume = {11}, journal = {Land}, number = {2}, issn = {2073-445X}, doi = {10.3390/land11020268}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-262078}, year = {2022}, abstract = {Forest conservation is of particular concern in tropical regions where a large refuge of biodiversity is still existing. These areas are threatened by deforestation, forest degradation and fragmentation. Especially, pressures of anthropogenic activities adjacent to these areas significantly influence conservation effectiveness. Ecuador was chosen as study area since it is a globally relevant center of forest ecosystems and biodiversity. We identified hotspots of deforestation on the national level of continental Ecuador between 1990 and 2018, analyzed the most significant drivers of deforestation on national and biome level (the Coast, the Andes, The Amazon) as well as inside protected areas in Ecuador by using multiple regression analysis. We separated the national system of protected areas (SNAP) into higher and lower protection levels. Besides SNAP, we also considered Biosphere Reserves (BRs) and Ramsar sites. In addition, we investigated the rates and spatial patterns of deforestation in protected areas and buffer zones (5 km and 10 km outwards the protected area boundaries) using landscape metrics. Between 1990 and 2018, approximately 4\% of the accumulated deforestation occurred within the boundaries of SNAP, and up to 25.5\% in buffer zones. The highest rates of deforestation have been found in the 5 km buffer zone around the protected areas with the highest protection level. Protected areas and their buffer zones with higher protection status were identified as the most deforested areas among SNAP. BRs had the highest deforestation rates among all protected areas but most of these areas just became BRs after the year 2000. The most important driver of deforestation is agriculture. Other relevant drivers differ between the biomes. The results suggest that the SNAP is generally effective to prevent deforestation within their protection boundaries. However, deforestation around protected areas can undermine conservation strategies to sustain biodiversity. Actions to address such dynamics and patterns of deforestation and forest fragmentation, and developing conservation strategies of their landscape context are urgently needed especially in the buffer zones of areas with the highest protection status.}, language = {en} } @article{SognoTraidlHoffmannKuenzer2020, author = {Sogno, Patrick and Traidl-Hoffmann, Claudia and Kuenzer, Claudia}, title = {Earth Observation data supporting non-communicable disease research: a review}, series = {Remote Sensing}, volume = {12}, journal = {Remote Sensing}, number = {16}, issn = {2072-4292}, doi = {10.3390/rs12162541}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-211113}, year = {2020}, abstract = {A disease is non-communicable when it is not transferred from one person to another. Typical examples include all types of cancer, diabetes, stroke, or allergies, as well as mental diseases. Non-communicable diseases have at least two things in common — environmental impact and chronicity. These diseases are often associated with reduced quality of life, a higher rate of premature deaths, and negative impacts on a countries' economy due to healthcare costs and missing work force. Additionally, they affect the individual's immune system, which increases susceptibility toward communicable diseases, such as the flu or other viral and bacterial infections. Thus, mitigating the effects of non-communicable diseases is one of the most pressing issues of modern medicine, healthcare, and governments in general. Apart from the predisposition toward such diseases (the genome), their occurrence is associated with environmental parameters that people are exposed to (the exposome). Exposure to stressors such as bad air or water quality, noise, extreme heat, or an overall unnatural surrounding all impact the susceptibility to non-communicable diseases. In the identification of such environmental parameters, geoinformation products derived from Earth Observation data acquired by satellites play an increasingly important role. In this paper, we present a review on the joint use of Earth Observation data and public health data for research on non-communicable diseases. We analyzed 146 articles from peer-reviewed journals (Impact Factor ≥ 2) from all over the world that included Earth Observation data and public health data for their assessments. Our results show that this field of synergistic geohealth analyses is still relatively young, with most studies published within the last five years and within national boundaries. While the contribution of Earth Observation, and especially remote sensing-derived geoinformation products on land surface dynamics is on the rise, there is still a huge potential for transdisciplinary integration into studies. We see the necessity for future research and advocate for the increased incorporation of thematically profound remote sensing products with high spatial and temporal resolution into the mapping of exposomes and thus the vulnerability and resilience assessment of a population regarding non-communicable diseases.}, language = {en} } @article{SaddiqueUsmanBernhofer2019, author = {Saddique, Naeem and Usman, Muhammad and Bernhofer, Christian}, title = {Simulating the impact of climate change on the hydrological regimes of a sparsely gauged mountainous basin, northern Pakistan}, series = {Water}, volume = {11}, journal = {Water}, number = {10}, issn = {2073-4441}, doi = {10.3390/w11102141}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-193175}, year = {2019}, abstract = {Projected climate changes for the 21st century may cause great uncertainties on the hydrology of a river basin. This study explored the impacts of climate change on the water balance and hydrological regime of the Jhelum River Basin using the Soil and Water Assessment Tool (SWAT). Two downscaling methods (SDSM, Statistical Downscaling Model and LARS-WG, Long Ashton Research Station Weather Generator), three Global Circulation Models (GCMs), and two representative concentration pathways (RCP4.5 and RCP8.5) for three future periods (2030s, 2050s, and 2090s) were used to assess the climate change impacts on flow regimes. The results exhibited that both downscaling methods suggested an increase in annual streamflow over the river basin. There is generally an increasing trend of winter and autumn discharge, whereas it is complicated for summer and spring to conclude if the trend is increasing or decreasing depending on the downscaling methods. Therefore, the uncertainty associated with the downscaling of climate simulation needs to consider, for the best estimate, the impact of climate change, with its uncertainty, on a particular basin. The study also resulted that water yield and evapotranspiration in the eastern part of the basin (sub-basins at high elevation) would be most affected by climate change. The outcomes of this study would be useful for providing guidance in water management and planning for the river basin under climate change.}, language = {en} } @article{ThonfeldGessnerHolzwarthetal.2022, author = {Thonfeld, Frank and Gessner, Ursula and Holzwarth, Stefanie and Kriese, Jennifer and da Ponte, Emmanuel and Huth, Juliane and Kuenzer, Claudia}, title = {A first assessment of canopy cover loss in Germany's forests after the 2018-2020 drought years}, series = {Remote Sensing}, volume = {14}, journal = {Remote Sensing}, number = {3}, issn = {2072-4292}, doi = {10.3390/rs14030562}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-255306}, year = {2022}, abstract = {Central Europe was hit by several unusually strong periods of drought and heat between 2018 and 2020. These droughts affected forest ecosystems. Cascading effects with bark beetle infestations in spruce stands were fatal to vast forest areas in Germany. We present the first assessment of canopy cover loss in Germany for the period of January 2018-April 2021. Our approach makes use of dense Sentinel-2 and Landsat-8 time-series data. We computed the disturbance index (DI) from the tasseled cap components brightness, greenness, and wetness. Using quantiles, we generated monthly DI composites and calculated anomalies in a reference period (2017). From the resulting map, we calculated the canopy cover loss statistics for administrative entities. Our results show a canopy cover loss of 501,000 ha for Germany, with large regional differences. The losses were largest in central Germany and reached up to two-thirds of coniferous forest loss in some districts. Our map has high spatial (10 m) and temporal (monthly) resolution and can be updated at any time.}, language = {en} } @article{DirscherlDietzKneiseletal.2021, author = {Dirscherl, Mariel and Dietz, Andreas J. and Kneisel, Christof and Kuenzer, Claudia}, title = {A novel method for automated supraglacial lake mapping in Antarctica using Sentinel-1 SAR imagery and deep learning}, series = {Remote Sensing}, volume = {13}, journal = {Remote Sensing}, number = {2}, issn = {2072-4292}, doi = {10.3390/rs13020197}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-222998}, year = {2021}, abstract = {Supraglacial meltwater accumulation on ice sheets can be a main driver for accelerated ice discharge, mass loss, and global sea-level-rise. With further increasing surface air temperatures, meltwater-induced hydrofracturing, basal sliding, or surface thinning will cumulate and most likely trigger unprecedented ice mass loss on the Greenland and Antarctic ice sheets. While the Greenland surface hydrological network as well as its impacts on ice dynamics and mass balance has been studied in much detail, Antarctic supraglacial lakes remain understudied with a circum-Antarctic record of their spatio-temporal development entirely lacking. This study provides the first automated supraglacial lake extent mapping method using Sentinel-1 synthetic aperture radar (SAR) imagery over Antarctica and complements the developed optical Sentinel-2 supraglacial lake detection algorithm presented in our companion paper. In detail, we propose the use of a modified U-Net for semantic segmentation of supraglacial lakes in single-polarized Sentinel-1 imagery. The convolutional neural network (CNN) is implemented with residual connections for optimized performance as well as an Atrous Spatial Pyramid Pooling (ASPP) module for multiscale feature extraction. The algorithm is trained on 21,200 Sentinel-1 image patches and evaluated in ten spatially or temporally independent test acquisitions. In addition, George VI Ice Shelf is analyzed for intra-annual lake dynamics throughout austral summer 2019/2020 and a decision-level fused Sentinel-1 and Sentinel-2 maximum lake extent mapping product is presented for January 2020 revealing a more complete supraglacial lake coverage (~770 km\(^2\)) than the individual single-sensor products. Classification results confirm the reliability of the proposed workflow with an average Kappa coefficient of 0.925 and a F\(_1\)-score of 93.0\% for the supraglacial water class across all test regions. Furthermore, the algorithm is applied in an additional test region covering supraglacial lakes on the Greenland ice sheet which further highlights the potential for spatio-temporal transferability. Future work involves the integration of more training data as well as intra-annual analyses of supraglacial lake occurrence across the whole continent and with focus on supraglacial lake development throughout a summer melt season and into Antarctic winter.}, language = {en} } @article{OttingerBachoferHuthetal.2021, author = {Ottinger, Marco and Bachofer, Felix and Huth, Juliane and Kuenzer, Claudia}, title = {Mapping aquaculture ponds for the coastal zone of Asia with Sentinel-1 and Sentinel-2 time series}, series = {Remote Sensing}, volume = {14}, journal = {Remote Sensing}, number = {1}, issn = {2072-4292}, doi = {10.3390/rs14010153}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-252207}, year = {2021}, abstract = {Asia dominates the world's aquaculture sector, generating almost 90 percent of its total annual global production. Fish, shrimp, and mollusks are mainly farmed in land-based pond aquaculture systems and serve as a primary protein source for millions of people. The total production and area occupied for pond aquaculture has expanded rapidly in coastal regions in Asia since the early 1990s. The growth of aquaculture was mainly boosted by an increasing demand for fish and seafood from a growing world population. The aquaculture sector generates income and employment, contributes to food security, and has become a billion-dollar industry with high socio-economic value, but has also led to severe environmental degradation. In this regard, geospatial information on aquaculture can support the management of this growing food sector for the sustainable development of coastal ecosystems, resources, and human health. With free and open access to the rapidly growing volume of data from the Copernicus Sentinel missions as well as machine learning algorithms and cloud computing services, we extracted coastal aquaculture at a continental scale. We present a multi-sensor approach that utilizes Earth observation time series data for the mapping of pond aquaculture within the entire Asian coastal zone, defined as the onshore area up to 200 km from the coastline. In this research, we developed an object-based framework to detect and extract aquaculture at a single-pond level based on temporal features derived from high-spatial-resolution SAR and optical satellite data acquired from the Sentinel-1 and Sentinel-2 satellites. In a second step, we performed spatial and statistical data analyses of the Earth-observation-derived aquaculture dataset to investigate spatial distribution and identify production hotspots at various administrative units at regional, national, and sub-national scale.}, language = {en} } @phdthesis{Rodrian2009, author = {Rodrian, Philipp T.}, title = {Das Erbe der deutschen Kolonialzeit in Namibia im Fokus des "Tourist Gaze" deutscher Touristen}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-231424}, school = {Universit{\"a}t W{\"u}rzburg}, pages = {210}, year = {2009}, abstract = {Die Studie besch{\"a}ftigt sich mit der Wahrnehmung des deutschen Kolonialerbes in Namibia aus Sicht deutscher Touristen. Namibia ist das Land in Afrika welches die st{\"a}rkste Durchdringung mit Elementen der deutschen Kolonialzeit aufweist. Dar{\"u}ber hinaus zeichnet sich dieses Land durch eine sehr hohe touristische Bedeutung des deutschen Quellmarktes aus. Weiterhin ist die gemeinsame koloniale Vergangenheit weder bilateral noch innerhalb Namibias aufgearbeitet, was der Thematik eine gesellschaftspolitische Komponente verleiht. Die Analyse der touristischen Wahrnehmung basiert auf 103 qualitativen Interviews mit deutschen Touristen in Namibia. Neben der Perspektive der Reisenden werden Akteure untersucht, welche den ‚Blick' der Touristen lenken und beeinflussen. Dabei kommen eine Inhaltsanalyse von deutschsprachiger Reiseliteratur sowie teilnehmende Beobachtungen bei Stadtf{\"u}hrungen mit lokalen Reiseleitern in der Stadt zum Einsatz. Die Resultate zeigen, dass die Touristen das Erbe der deutschen Kolonialzeit als sehr heterogenes Ph{\"a}nomen interpretieren. Durch das Aufsummieren der vielf{\"a}ltigen Erfahrungen mit gelebtem und gebautem Kolonialerbe wird die Wahrnehmung geographisch wirksam, da die Eindr{\"u}cke auf R{\"a}ume und Menschen {\"u}bertragen werden und nicht auf punktuellen Elementen verharren. Aufgrund von Unterdr{\"u}ckung und Verbrechen in der Kolonialzeit sehen die befragten Touristen das deutsche Erbe in Namibia als ein ‚schwieriges' an, das kaum nostalgische Gef{\"u}hle ausl{\"o}st, sondern eher zu einer kritischen Auseinandersetzung mit der Geschichte anregt. Der Grad dieser Dissonanz ist stark davon abh{\"a}ngig, in wie weit die koloniale Thematik nach Ansicht der Touristen in aktuellem Bezug steht oder aber als nicht mehr relevante Vergangenheit interpretiert wird. Neben der ‚Dissonanz' k{\"o}nnen die Touristen anhand der beiden weiteren Indikatoren ‚Interesse' - im Sinne einer Auseinandersetzung und Informiertheit - sowie ‚Attraktion' - als touristische Bedeutung - typologisiert werden. Die entscheidende Determinante f{\"u}r die Charakterisierung der Befragten stellt das Maß der empfundenen Dissonanz dar. Weiterhin l{\"a}sst sich eine Differenzierung in Touristen mit einer vorbereiteten und organisierten und solche mit einer unvorbereiteten und spontanen Konfrontation mit dem deutschen Erbe vornehmen. Insgesamt k{\"o}nnen f{\"u}nf Typen - ‚klassische Heritage-Touristen', ‚spontane Heritage-Touristen, ‚Kritiker', ‚historische motivierte Touristen' und ‚Sightseeing-Touristen' - identifiziert werden, wobei den drei erstgenannten eine Wahrnehmung als ‚schwieriges', dissonantes Erbe immanent ist.}, subject = {Namibia}, language = {de} } @phdthesis{Poppitz2022, author = {Poppitz, Hanka}, title = {Untersuchungen zur Alteration von R{\"u}ckstandshalden der Kaliindustrie im Werratal}, doi = {10.25972/OPUS-25380}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-253802}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2022}, abstract = {Im Zuge der Aufbereitung von Kalirohsalzen fallen weltweit feste R{\"u}ckst{\"a}nde an, die auf Großhalden entsorgt werden. Die Aufhaldung und die von den R{\"u}ckstandshalden ausgehenden Umweltauswirkungen unterliegen in Deutschland der Kontrolle durch die zust{\"a}ndigen Bergbeh{\"o}rden. Um die Emissionen besser quantifizieren zu k{\"o}nnen und die Eignung technischer Minderungsmaßnahmen zu beurteilen, erfolgte im Rahmen der Genehmigungsverfahren zur Erweiterung der R{\"u}ckstandshalden an den Standorten Hattorf und Wintershall die Erkundung des Haldenk{\"o}rpers durch Bohrungen mit Fokus auf die darin ablaufenden Str{\"o}mungsprozesse. Eine Modellvorstellung zur Zonierung der Halde im Hinblick auf Str{\"o}mungsprozesse war zun{\"a}chst anhand von Haldenbohrungen am Standort Hattorf entwickelt worden. Das Ziel dieser Arbeit war, mittels der Bohrergebnisse einer weiteren Haldenbohrung am Standort Wintershall die {\"U}bertragbarkeit der zuvor in Hattorf gefundenen Gegebenheiten zu {\"u}berpr{\"u}fen und den Kenntnisstand zu Str{\"o}mungs- und Alterationsprozessen innerhalb der Halde zu verbessern. Im Zuge der Haldenbohrungen erfolgten bohrbegleitende Untersuchungen (Abflussmessungen, Kamerabefahrungen, geophysikalische und geohydraulische Untersuchungen), und an dem Bohrkernmaterial und den Haldenl{\"o}sungen wurde ein umfangreiches Laboruntersuchungsprogramm ausgef{\"u}hrt, das chemische und mineralogische Analysen sowie Untersuchungen der physikalischen und hydraulischen Eigenschaften des R{\"u}ckstands umfasste. Zus{\"a}tzlich wurden erg{\"a}nzende Gef{\"u}geuntersuchungen (D{\"u}nnschliffuntersuchungen am Rasterelektronen-Mikroskop und exemplarische CT-Untersuchungen) an Probenmaterial der Halde Hattorf durchgef{\"u}hrt, um mittels visueller Untersuchungen insbesondere die Rolle {\"u}bersch{\"u}tteter ehemaliger Haldenoberfl{\"a}chen f{\"u}r das Str{\"o}mungsgeschehen im Haldenk{\"o}rper zu erkunden. Unter Ber{\"u}cksichtigung aller Ergebnisse wurden die Str{\"o}mungs- und Alterationsprozesse im R{\"u}ckstand beschrieben. Die maßgebliche Erkenntnis im Hinblick auf das Str{\"o}mungsgeschehen im Haldenk{\"o}rper ist, dass in dessen Porenraum keine S{\"a}ttigung besteht und dieser in allen Bereichen mit einem Gemisch aus L{\"o}sung und Luft gef{\"u}llt ist, so dass die Gesetzm{\"a}ßigkeiten der Zweiphasenstr{\"o}mung maßgeblich sind. Die bislang zur Bewertung von Str{\"o}mungsprozessen {\"u}blichen Durchl{\"a}ssigkeitsbeiwerte sind damit ungeeignet, da sie f{\"u}r ges{\"a}ttigte Bereiche gelten. {\"U}bereinstimmend wurde mit einer Reihe von Ergebnissen belegt, dass die Str{\"o}mungsprozesse im Haldenk{\"o}rper an bevorzugte Wegsamkeiten gebunden sind, bei denen es sich ausweislich der Gef{\"u}geuntersuchungen um ein System miteinander verbundenen Sekund{\"a}rporen handelt. Der R{\"u}ckstand ist zu charakterisieren als ein Nebeneinander aus diesen Wegsamkeiten und unbeeinflussten, aggregierten Bereichen. Des Weiteren wurde gezeigt, dass der Niederschlagseinfluss zur Teufe hin abnimmt, und es wurden Kriterien zum Nachweis von Niederschlagsunbeeinflussten Bereichen formuliert. Die Arbeit hat damit auch gezeigt, dass die Modellvorstellung, welche die Halde in eine f{\"u}r die Str{\"o}mungsprozesse maßgebliche Haldenmantelzone, eine gering durchl{\"a}ssige Kernzone und eine dazwischen befindliche {\"U}bergangszone mit gradueller {\"A}nderung der Eigenschaften unterteilt, grunds{\"a}tzlich auch auf den Standort Wintershall {\"u}bertragbar ist. Das Modell des Haldenk{\"o}rpers wurde weiter detailliert und zus{\"a}tzliche Kriterien zur Verortung der einzelnen Zonen im Haldenk{\"o}rper abgeleitet. Insbesondere wurde im Haldenmantelbereich eine charakteristische Randzone ausgehalten, welche im Ergebnis einer intensiven Durchstr{\"o}mung mit un- bzw. teilges{\"a}ttigten L{\"o}sungen selektiv an Wertstoff-Restgehalten abgereichert ist. Sie 2 wird von den unterlagernden reaktiven Zonen durch die L{\"o}sungsfronten f{\"u}r Kalium und Magnesium abgegrenzt. Aufbauend auf der erweiterten Modellvorstellung wurde die Zonierung f{\"u}r die Haldenbohrung am Standort Wintershall abgeleitet. Besonderes Augenmerk galt im Rahmen aller Untersuchungen der Wirkung von {\"u}bersch{\"u}tteten ehemaligen Haldenoberfl{\"a}chen, die als Sch{\"u}ttfl{\"a}chen bezeichnet werden. Es zeigte sich anhand der Untersuchungen, dass die Relevanz von Sch{\"u}ttfl{\"a}chen f{\"u}r das Str{\"o}mungsgeschehen abh{\"a}ngig von der Sch{\"u}tthistorie ist, und dass diese, selbst wenn sie aktiv am Str{\"o}mungsgeschehen teilnehmen, die Gegebenheiten im Haldenk{\"o}rper nur lokal {\"u}berpr{\"a}gen. Das Ziel der Aufstellung eines Modells zu Str{\"o}mungsprozessen im Haldenk{\"o}rper besteht in der Beurteilung der von diesen Halden ausgehenden Umweltauswirkungen. Dar{\"u}ber hinaus dienen die Erkenntnisse der Einsch{\"a}tzung der Wirksamkeit der bereits ergriffenen bzw. noch zu ergreifenden Schutz- und Emissionsminderungsmaßnahmen sowie der Planung zuk{\"u}nftiger Maßnahmen zur Wiedernutzbarmachung der Tagesoberfl{\"a}che und zur Erstellung von Prognosen. In diesem Sinne wurden aus den Ergebnissen der Arbeit abschließend Empfehlungen f{\"u}r technische Konzepte und den Haldenbetrieb abgeleitet.}, subject = {Kaliindustrie}, language = {de} } @article{PhilippWegmannKuebertFlock2021, author = {Philipp, Marius and Wegmann, Martin and K{\"u}bert-Flock, Carina}, title = {Quantifying the Response of German Forests to Drought Events via Satellite Imagery}, series = {Remote Sensing}, volume = {13}, journal = {Remote Sensing}, number = {9}, issn = {2072-4292}, doi = {10.3390/rs13091845}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-239575}, year = {2021}, abstract = {Forest systems provide crucial ecosystem functions to our environment, such as balancing carbon stocks and influencing the local, regional and global climate. A trend towards an increasing frequency of climate change induced extreme weather events, including drought, is hereby a major challenge for forest management. Within this context, the application of remote sensing data provides a powerful means for fast, operational and inexpensive investigations over large spatial scales and time. This study was dedicated to explore the potential of satellite data in combination with harmonic analyses for quantifying the vegetation response to drought events in German forests. The harmonic modelling method was compared with a z-score standardization approach and correlated against both, meteorological and topographical data. Optical satellite imagery from Landsat and the Moderate Resolution Imaging Spectroradiometer (MODIS) was used in combination with three commonly applied vegetation indices. Highest correlation scores based on the harmonic modelling technique were computed for the 6th harmonic degree. MODIS imagery in combination with the Normalized Difference Vegetation Index (NDVI) generated hereby best results for measuring spectral response to drought conditions. Strongest correlation between remote sensing data and meteorological measures were observed for soil moisture and the self-calibrated Palmer Drought Severity Index (scPDSI). Furthermore, forests regions over sandy soils with pine as the dominant tree type were identified to be particularly vulnerable to drought. In addition, topographical analyses suggested mitigated drought affects along hill slopes. While the proposed approaches provide valuable information about vegetation dynamics as a response to meteorological weather conditions, standardized in-situ measurements over larger spatial scales and related to drought quantification are required for further in-depth quality assessment of the used methods and data.}, language = {en} }