@article{BaumhauerBuscheSponholz1989,
  author    = {Baumhauer, Roland and Busche, Detlef and Sponholz, Barbara},
  title     = {Reliefgeschichte und Pal{\"a}oklima des saharischen Ost-Niger},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-55378},
  year      = {1989},
  abstract  = {Der gr{\"o}ßte Teil des zentralsaharischen Reliefs ist unter dem Einfluß nicht-arider Klimate gebildet worden. Andererseits gab es im Pleistoz{\"a}n {\"a}olisch gepr{\"a}gte aride Phasen, die extremer als heutige gewesen sind. Der Kenntnisstand zur Reliefgeschichte erlaubt es, daraus die Grundz{\"u}ge der Klimageschichte eines großen Teils der s{\"u}dlich-zentralen Sahara abzuleiten.},
  subject      = {Geographie},
  language  = {de}
}
@article{AyalaCarrilloFarfanCardenasNielsenetal.2022,
  author    = {Ayala-Carrillo, Mariana and Farf{\´a}n, Michelle and C{\´a}rdenas-Nielsen, Anah{\´i} and Lemoine-Rodr{\´i}guez, Richard},
  title     = {Are wildfires in the wildland-urban interface increasing temperatures? A land surface temperature assessment in a semi-arid Mexican city},
  series = {Land},
  volume    = {11},
  journal   = {Land},
  number    = {12},
  issn      = {2073-445X},
  doi       = {10.3390/land11122105},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-297308},
  year      = {2022},
  abstract  = {High rates of land conversion due to urbanization are causing fragmented and dispersed spatial patterns in the wildland-urban interface (WUI) worldwide. The occurrence of anthropogenic fires in the WUI represents an important environmental and social issue, threatening not only vegetated areas but also periurban inhabitants, as is the case in many Latin American cities. However, research has not focused on the dynamics of the local climate in the WUI. This study analyzes whether wildfires contribute to the increase in land surface temperature (LST) in the WUI of the metropolitan area of the city of Guanajuato (MACG), a semi-arid Mexican city. We estimated the pre- and post-fire LST for 2018-2021. Spatial clusters of high LST were detected using hot spot analysis and examined using ANOVA and Tukey's post-hoc statistical tests to assess whether LST is related to the spatial distribution of wildfires during our study period. Our results indicate that the areas where the wildfires occurred, and their surroundings, show higher LST. This has negative implications for the local ecosystem and human population, which lacks adequate infrastructure and services to cope with the effects of rising temperatures. This is the first study assessing the increase in LST caused by wildfires in a WUI zone in Mexico.},
  language  = {en}
}
@article{AtaeeMaghsoudiLatifietal.2019,
  author    = {Ataee, Mohammad Sadegh and Maghsoudi, Yasser and Latifi, Hooman and Fadaie, Farhad},
  title     = {Improving estimation accuracy of growing stock by multi-frequency SAR and multi-spectral data over Iran's heterogeneously-structured broadleaf Hyrcanian forests},
  series = {Forests},
  volume    = {10},
  journal   = {Forests},
  number    = {8},
  issn      = {1999-4907},
  doi       = {10.3390/f10080641},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-197212},
  year      = {2019},
  abstract  = {Via providing various ecosystem services, the old-growth Hyrcanian forests play a crucial role in the environment and anthropogenic aspects of Iran and beyond. The amount of growing stock volume (GSV) is a forest biophysical parameter with great importance in issues like economy, environmental protection, and adaptation to climate change. Thus, accurate and unbiased estimation of GSV is also crucial to be pursued across the Hyrcanian. Our goal was to investigate the potential of ALOS-2 and Sentinel-1's polarimetric features in combination with Sentinel-2 multi-spectral features for the GSV estimation in a portion of heterogeneously-structured and mountainous Hyrcanian forests. We used five different kernels by the support vector regression (nu-SVR) for the GSV estimation. Because each kernel differently models the parameters, we separately selected features for each kernel by a binary genetic algorithm (GA). We simultaneously optimized R\(^2\) and RMSE in a suggested GA fitness function. We calculated R\(^2\), RMSE to evaluate the models. We additionally calculated the standard deviation of validation metrics to estimate the model's stability. Also for models over-fitting or under-fitting analysis, we used mean difference (MD) index. The results suggested the use of polynomial kernel as the final model. Despite multiple methodical challenges raised from the composition and structure of the study site, we conclude that the combined use of polarimetric features (both dual and full) with spectral bands and indices can improve the GSV estimation over mixed broadleaf forests. This was partially supported by the use of proposed evaluation criterion within the GA, which helped to avoid the curse of dimensionality for the applied SVR and lowest over estimation or under estimation.},
  language  = {en}
}
@article{ArendtReinhardtImjelaSchulteetal.2021,
  author    = {Arendt, Robert and Reinhardt-Imjela, Christian and Schulte, Achim and Faulstich, Leona and Ullmann, Tobias and Beck, Lorenz and Martinis, Sandro and Johannes, Petrina and Lengricht, Joachim},
  title     = {Natural pans as an important surface water resource in the Cuvelai Basin — Metrics for storage volume calculations and identification of potential augmentation sites},
  series = {Water},
  volume    = {13},
  journal   = {Water},
  number    = {2},
  issn      = {2073-4441},
  doi       = {10.3390/w13020177},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-223019},
  year      = {2021},
  abstract  = {Numerous ephemeral rivers and thousands of natural pans characterize the transboundary Iishana-System of the Cuvelai Basin between Namibia and Angola. After the rainy season, surface water stored in pans is often the only affordable water source for many people in rural areas. High inter- and intra-annual rainfall variations in this semiarid environment provoke years of extreme flood events and long periods of droughts. Thus, the issue of water availability is playing an increasingly important role in one of the most densely populated and fastest growing regions in southwestern Africa. Currently, there is no transnational approach to quantifying the potential storage and supply functions of the Iishana-System. To bridge these knowledge gaps and to increase the resilience of the local people's livelihood, suitable pans for expansion as intermediate storage were identified and their metrics determined. Therefore, a modified Blue Spot Analysis was performed, based on the high-resolution TanDEM-X digital elevation model. Further, surface area-volume ratio calculations were accomplished for finding suitable augmentation sites in a first step. The potential water storage volume of more than 190,000 pans was calculated at 1.9 km\(^3\). Over 2200 pans were identified for potential expansion to facilitate increased water supply and flood protection in the future.},
  language  = {en}
}
@article{AppelHardaker2022,
  author    = {Appel, Alexandra and Hardaker, Sina},
  title     = {Einzelhandel als Katalysator f{\"u}r nachhaltige urbane Radlogistik? - W{\"u}Livery, ein Fallbeispiel aus W{\"u}rzburg},
  series = {Standort},
  volume    = {46},
  journal   = {Standort},
  number    = {1},
  issn      = {1432-220X},
  doi       = {10.1007/s00548-021-00758-y},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-268437},
  pages     = {9-15},
  year      = {2022},
  abstract  = {Die Covid-19-Pandemie gilt in vielen gesellschaftlichen Teilbereichen als Beschleuniger f{\"u}r Transformationsprozesse. Auch im Bereich der Organisation urbaner Logistik und Einzelhandelslandschaften etablieren sich neue Akteur*innen und Funktionen. Logistiker*innen integrieren lokale Onlinemarktpl{\"a}tze in ihre Profile und der station{\"a}re Einzelhandel generiert Wettbewerbsf{\"a}higkeit gegen{\"u}ber großen Onlineh{\"a}ndler*innen {\"u}ber die Nutzung lokaler Radlogistiknetzwerke, mittels derer Lieferungen noch am Tag der Bestellung (Same-Day-Delivery) verteilt werden k{\"o}nnen. Damit leisten die involvierten Akteur*innen potenziell auch einen Beitrag zur Nachhaltigkeitstransformation im Bereich urbaner Logistiksysteme. Im Fokus steht das Fallbeispiel W{\"u}Livery, ein Kooperationsprojekt des Stadtmarketingvereins, der Wirtschaftsf{\"o}rderung, Radlogistiker*innen sowie Einzelh{\"a}ndler*innen in W{\"u}rzburg, welches w{\"a}hrend des zweiten coronabedingten Lockdowns im November 2020 umgesetzt wurde. Die entstehenden Dynamiken und Organisationsformen werden auf Basis von 11 Expert*inneninterviews dargestellt und analysiert. Es kann gezeigt werden, dass st{\"a}dtische Akteur*innen grundlegende Mediator*innen f{\"u}r Transformationsprozesse darstellen und Einzelh{\"a}ndler*innen und lokale Onlinemarktpl{\"a}tze als Katalysator*innen fungieren k{\"o}nnen. Das ist auch vor dem Hintergrund planerischer und politischer Kommunikationsprozesse zur Legitimation neuer Verkehrsinfrastrukturen nutzbar, da die einzelnen Akteur*innengruppen in Austausch kommen und ein gesteigertes Bewusstsein f{\"u}r die jeweiligen Bedarfe entsteht.},
  language  = {de}
}
@article{AnsahAbuKleemannetal.2022,
  author    = {Ansah, Christabel Edena and Abu, Itohan-Osa and Kleemann, Janina and Mahmoud, Mahmoud Ibrahim and Thiel, Michael},
  title     = {Environmental contamination of a biodiversity hotspot — action needed for nature conservation in the Niger Delta, Nigeria},
  series = {Sustainability},
  volume    = {14},
  journal   = {Sustainability},
  number    = {21},
  issn      = {2071-1050},
  doi       = {10.3390/su142114256},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-297214},
  year      = {2022},
  abstract  = {The Niger Delta belongs to the largest swamp and mangrove forests in the world hosting many endemic and endangered species. Therefore, its conservation should be of highest priority. However, the Niger Delta is confronted with overexploitation, deforestation and pollution to a large extent. In particular, oil spills threaten the biodiversity, ecosystem services, and local people. Remote sensing can support the detection of spills and their potential impact when accessibility on site is difficult. We tested different vegetation indices to assess the impact of oil spills on the land cover as well as to detect accumulations (hotspots) of oil spills. We further identified which species, land cover types, and protected areas could be threatened in the Niger Delta due to oil spills. The results showed that the Enhanced Vegetation Index, the Normalized Difference Vegetation Index, and the Soil Adjusted Vegetation Index were more sensitive to the effects of oil spills on different vegetation cover than other tested vegetation indices. Forest cover was the most affected land-cover type and oil spills also occurred in protected areas. Threatened species are inhabiting the Niger Delta Swamp Forest and the Central African Mangroves that were mainly affected by oil spills and, therefore, strong conservation measures are needed even though security issues hamper the monitoring and control.},
  language  = {en}
}
@article{AkhundzadahSoltaniAich2020,
  author    = {Akhundzadah, Noor Ahmad and Soltani, Salim and Aich, Valentin},
  title     = {Impacts of climate change on the water resources of the Kunduz River Basin, Afghanistan},
  series = {Climate},
  volume    = {8},
  journal   = {Climate},
  number    = {10},
  issn      = {2225-1154},
  doi       = {10.3390/cli8100102},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-213199},
  year      = {2020},
  abstract  = {The Kunduz River is one of the main tributaries of the Amu Darya Basin in North Afghanistan. Many communities live in the Kunduz River Basin (KRB), and its water resources have been the basis of their livelihoods for many generations. This study investigates climate change impacts on the KRB catchment. Rare station data are, for the first time, used to analyze systematic trends in temperature, precipitation, and river discharge over the past few decades, while using Mann-Kendall and Theil-Sen trend statistics. The trends show that the hydrology of the basin changed significantly over the last decades. A comparison of landcover data of the river basin from 1992 and 2019 shows significant changes that have additional impact on the basin hydrology, which are used to interpret the trend analysis. There is considerable uncertainty due to the data scarcity and gaps in the data, but all results indicate a strong tendency towards drier conditions. An extreme warming trend, partly above 2 °C since the 1960s in combination with a dramatic precipitation decrease by more than -30\% lead to a strong decrease in river discharge. The increasing glacier melt compensates the decreases and leads to an increase in runoff only in the highland parts of the upper catchment. The reduction of water availability and the additional stress on the land leads to a strong increase of barren land and a reduction of vegetation cover. The detected trends and changes in the basin hydrology demand an active management of the already scarce water resources in order to sustain water supply for agriculture and ecosystems in the KRB.},
  language  = {en}
}
@article{AbdullahiWesselHuberetal.2019,
  author    = {Abdullahi, Sahra and Wessel, Birgit and Huber, Martin and Wendleder, Anna and Roth, Achim and Kuenzer, Claudia},
  title     = {Estimating penetration-related X-band InSAR elevation bias: a study over the Greenland ice sheet},
  series = {Remote Sensing},
  volume    = {11},
  journal   = {Remote Sensing},
  number    = {24},
  issn      = {2072-4292},
  doi       = {10.3390/rs11242903},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-193902},
  year      = {2019},
  abstract  = {Accelerating melt on the Greenland ice sheet leads to dramatic changes at a global scale. Especially in the last decades, not only the monitoring, but also the quantification of these changes has gained considerably in importance. In this context, Interferometric Synthetic Aperture Radar (InSAR) systems complement existing data sources by their capability to acquire 3D information at high spatial resolution over large areas independent of weather conditions and illumination. However, penetration of the SAR signals into the snow and ice surface leads to a bias in measured height, which has to be corrected to obtain accurate elevation data. Therefore, this study purposes an easy transferable pixel-based approach for X-band penetration-related elevation bias estimation based on single-pass interferometric coherence and backscatter intensity which was performed at two test sites on the Northern Greenland ice sheet. In particular, the penetration bias was estimated using a multiple linear regression model based on TanDEM-X InSAR data and IceBridge laser-altimeter measurements to correct TanDEM-X Digital Elevation Model (DEM) scenes. Validation efforts yielded good agreement between observations and estimations with a coefficient of determination of R\(^2\) = 68\% and an RMSE of 0.68 m. Furthermore, the study demonstrates the benefits of X-band penetration bias estimation within the application context of ice sheet elevation change detection.},
  language  = {en}
}