@phdthesis{Rolf2020,
  author    = {Rolf, Werner},
  title     = {Peri-urban farmland included in green infrastructure strategies promotes transformation pathways towards sustainable urban development},
  doi       = {10.25932/publishup-47700},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-477002},
  school      = {Universit{\"a}t Potsdam},
  pages     = {IV, 116},
  year      = {2020},
  abstract  = {Urbanization and agricultural land use are two of the main drivers of global changes with effects on ecosystem functions and human wellbeing. Green Infrastructure is a new approach in spatial planning contributing to sustainable urban development, and to address urban challenges, such as biodiversity conservation, climate change adaptation, green economy development, and social cohesion. Because the research focus has been mainly on open green space structures, such as parks, urban forest, green building, street green, but neglected spatial and functional potentials of utilizable agricultural land, this thesis aims at fill this gap. This cumulative thesis addresses how agricultural land in urban and peri-urban landscapes can contribute to the development of urban green infrastructure as a strategy to promote sustainable urban development. Therefore, a number of different research approaches have been applied. First, a quantitative, GIS-based modeling approach looked at spatial potentials, addressing the heterogeneity of peri-urban landscape that defines agricultural potentials and constraints. Second, a participatory approach was applied, involving stakeholder opinions to evaluate multiple urban functions and benefits. Finally, an evidence synthesis was conducted to assess the current state of research on evidence to support future policy making at different levels. The results contribute to the conceptual understanding of urban green infrastructures as a strategic spatial planning approach that incorporates inner-urban utilizable agricultural land and the agriculturally dominated landscape at the outer urban fringe. It highlights the proposition that the linkage of peri-urban farmland with the green infrastructure concept can contribute to a network of multifunctional green spaces to provide multiple benefits to the urban system and to successfully address urban challenges. Four strategies are introduced for spatial planning with the contribution of peri-urban farmland to a strategically planned multifunctional network, namely the connecting, the productive, the integrated, and the adapted way. Finally, this thesis sheds light on the opportunities that arise from the integration of the peri- urban farmland in the green infrastructure concept to support transformation towards a more sustainable urban development. In particular, the inherent core planning principle of multifunctionality endorses the idea of co-benefits that are considered crucial to trigger transformative processes. This work concludes that the linkage of peri-urban farmland with the green infrastructure concept is a promising action field for the development of new pathways for urban transformation towards sustainable urban development. Along with these outcomes, attention is drawn to limitations that remain to be addressed by future research, especially the identification of further mechanisms required to support policy integration at all levels.},
  language  = {en}
}
@phdthesis{Schmitz2023,
  author    = {Schmitz, Se{\´a}n},
  title     = {Using low-cost sensors to gather high resolution measurements of air quality in urban environments and inform mobility policy},
  doi       = {10.25932/publishup-60105},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-601053},
  school      = {Universit{\"a}t Potsdam},
  pages     = {180},
  year      = {2023},
  abstract  = {Air pollution has been a persistent global problem in the past several hundred years. While some industrialized nations have shown improvements in their air quality through stricter regulation, others have experienced declines as they rapidly industrialize. The WHO's 2021 update of their recommended air pollution limit values reflects the substantial impacts on human health of pollutants such as NO2 and O3, as recent epidemiological evidence suggests substantial long-term health impacts of air pollution even at low concentrations. Alongside developments in our understanding of air pollution's health impacts, the new technology of low-cost sensors (LCS) has been taken up by both academia and industry as a new method for measuring air pollution. Due primarily to their lower cost and smaller size, they can be used in a variety of different applications, including in the development of higher resolution measurement networks, in source identification, and in measurements of air pollution exposure. While significant efforts have been made to accurately calibrate LCS with reference instrumentation and various statistical models, accuracy and precision remain limited by variable sensor sensitivity. Furthermore, standard procedures for calibration still do not exist and most proprietary calibration algorithms are black-box, inaccessible to the public. This work seeks to expand the knowledge base on LCS in several different ways: 1) by developing an open-source calibration methodology; 2) by deploying LCS at high spatial resolution in urban environments to test their capability in measuring microscale changes in urban air pollution; 3) by connecting LCS deployments with the implementation of local mobility policies to provide policy advice on resultant changes in air quality. In a first step, it was found that LCS can be consistently calibrated with good performance against reference instrumentation using seven general steps: 1) assessing raw data distribution, 2) cleaning data, 3) flagging data, 4) model selection and tuning, 5) model validation, 6) exporting final predictions, and 7) calculating associated uncertainty. By emphasizing the need for consistent reporting of details at each step, most crucially on model selection, validation, and performance, this work pushed forward with the effort towards standardization of calibration methodologies. In addition, with the open-source publication of code and data for the seven-step methodology, advances were made towards reforming the largely black-box nature of LCS calibrations. With a transparent and reliable calibration methodology established, LCS were then deployed in various street canyons between 2017 and 2020. Using two types of LCS, metal oxide (MOS) and electrochemical (EC), their performance in capturing expected patterns of urban NO2 and O3 pollution was evaluated. Results showed that calibrated concentrations from MOS and EC sensors matched general diurnal patterns in NO2 and O3 pollution measured using reference instruments. While MOS proved to be unreliable for discerning differences among measured locations within the urban environment, the concentrations measured with calibrated EC sensors matched expectations from modelling studies on NO2 and O3 pollution distribution in street canyons. As such, it was concluded that LCS are appropriate for measuring urban air quality, including for assisting urban-scale air pollution model development, and can reveal new insights into air pollution in urban environments. To achieve the last goal of this work, two measurement campaigns were conducted in connection with the implementation of three mobility policies in Berlin. The first involved the construction of a pop-up bike lane on Kottbusser Damm in response to the COVID-19 pandemic, the second surrounded the temporary implementation of a community space on B{\"o}ckhstrasse, and the last was focused on the closure of a portion of Friedrichstrasse to all motorized traffic. In all cases, measurements of NO2 were collected before and after the measure was implemented to assess changes in air quality resultant from these policies. Results from the Kottbusser Damm experiment showed that the bike-lane reduced NO2 concentrations that cyclists were exposed to by 22 ± 19\%. On Friedrichstrasse, the street closure reduced NO2 concentrations to the level of the urban background without worsening the air quality on side streets. These valuable results were communicated swiftly to partners in the city administration responsible for evaluating the policies' success and future, highlighting the ability of LCS to provide policy-relevant results. As a new technology, much is still to be learned about LCS and their value to academic research in the atmospheric sciences. Nevertheless, this work has advanced the state of the art in several ways. First, it contributed a novel open-source calibration methodology that can be used by a LCS end-users for various air pollutants. Second, it strengthened the evidence base on the reliability of LCS for measuring urban air quality, finding through novel deployments in street canyons that LCS can be used at high spatial resolution to understand microscale air pollution dynamics. Last, it is the first of its kind to connect LCS measurements directly with mobility policies to understand their influences on local air quality, resulting in policy-relevant findings valuable for decisionmakers. It serves as an example of the potential for LCS to expand our understanding of air pollution at various scales, as well as their ability to serve as valuable tools in transdisciplinary research.},
  language  = {en}
}
@techreport{Schrauth2022,
  type      = {Working Paper},
  author    = {Schrauth, Philipp},
  title     = {The Causal Effect of Cycling Infrastructure on Traffic and Accidents},
  series = {CEPA Discussion Papers},
  journal   = {CEPA Discussion Papers},
  number    = {48},
  issn      = {2628-653X},
  doi       = {10.25932/publishup-55335},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-553359},
  pages     = {56},
  year      = {2022},
  abstract  = {This paper analyzes the effect of new bicycle lanes on traffic volume, congestion, and accidents. Crucially, the new bike lanes replace existing car lanes thereby reducing available space for motorized traffic. In order to obtain causal estimates, I exploit the quasi-random timing and location of the newly built cycle lanes. Using an event study design, a two-way fixed effects model and the synthetic control group method on geo-coded data, I show that the construction of pop-up bike lanes significantly reduced average car speed by 8 to 12 percentage points (p.p.) and up to 16 p.p. in peak traffic hours. In contrast, the results for car volume are modest, while the data does not allow for a conclusive judgment of accidents.},
  language  = {en}
}
@phdthesis{SvirejevaHopkins2004,
  author    = {Svirejeva-Hopkins, Anastasia},
  title     = {Urbanised territories as a specific component of the global carbon cycle},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-0001512},
  school      = {Universit{\"a}t Potsdam},
  year      = {2004},
  abstract  = {Wir betrachten folgende Teile: die zus{\"a}tzlichen Kohlenstoff(C)-emissionen, welche aus der Umwandlung von nat{\"u}rlichem Umland durch Stadtwachstum resultieren, und die {\"A}nderung des C-Flusses durch 'urbanisierte' {\"O}kosysteme, soweit atmosph{\"a}risches C durch diese in umliegende nat{\"u}rliche {\"O}kosysteme entlang der Kette \“Atmosph{\"a}re -> Vegetation -> abgestorbene organische Substanzen\” gepumpt wird: d.h. C-Export; f{\"u}r den Zeitraum von 1980 bis 2050. Als Szenario nutzen wir Prognosen der regionalen Stadtbev{\"o}lkerung, welche durch ein 'Hybridmodell' generiert werden f{\"u}r acht Regionen. Alle Sch{\"a}tzungen der C-Fl{\"u}sse basieren auf zwei Modellen: das Regression Modell und das sogenannte G-Modell. Die Siedlungsfl{\"a}che, welche mit dem Wachstum der Stadtbev{\"o}lkerung zunimmt, wird in 'Gr{\"u}nfl{\"a}chen' (Parks, usw.), Geb{\"a}udefl{\"a}chen und informell st{\"a}dtisch genutzte Fl{\"a}chen (Slums, illegale Lagerpl{\"a}tze, usw.) unterteilt. Es werden j{\"a}hrlich die regionale und globale Dynamik der C-Emissionen und des C-Exports sowie die C-Gesamtbilanz berechnet. Dabei liefern beide Modelle qualitativ {\"a}hnliche Ergebnisse, jedoch gibt es einige quantitative Unterschiede. Im ersten Modell erreicht die globale Jahresemission f{\"u}r die Dekade 2020-2030 resultierend aus der Landnutzungs{\"a}nderung ein Maximum von 205 Mt/a. Die maximalen Beitr{\"a}ge zur globalen Emission werden durch China, die asiatische und die pazifische Region erbracht. Im zweiten Modell erh{\"o}ht sich die j{\"a}hrliche globale Emission von 1.12 GtC/a f{\"u}r 1980 auf 1.25 GtC/a f{\"u}r 2005 (1Gt = 109 t). Danach beginnt eine Reduzierung. Vergleichen wir das Emissionmaximum mit der Emission durch Abholzung im Jahre 1980 (1.36 GtC/a), k{\"o}nnen wir konstatieren, daß die Urbanisierung damit in vergleichbarer Gr{\"o}sse zur Emission beitr{\"a}gt. Bezogen auf die globale Dynamik des j{\"a}hrlichen C-Exports durch Urbanisierung beobachten wir ein monotones Wachstum bis zum nahezu dreifachen Wert von 24 MtC/a f{\"u}r 1980 auf 66 MtC/a f{\"u}r 2050 im ersten Modell, bzw. im zweiten Modell von 249 MtC/a f{\"u}r 1980 auf 505 MtC/a f{\"u}r 2050. Damit ist im zweiten Fall die Transportleistung der Siedlungsgebiete mit dem C-Transport durch Fl{\"u}sse in die Ozeane (196 .. 537 MtC/a) vergleichbar. Bei der Absch{\"a}tzung der Gesamtbilanz finden wir, daß die Urbanisierung die Bilanz in Richtung zu einer 'Senke' verschiebt. Entsprechend dem zweiten Modell beginnt sich die C-Gesamtbilanz (nach ann{\"a}hernder Konstanz) ab dem Jahre 2000 mit einer fast konstanten Rate zu verringern. Wenn das Maximum im Jahre 2000 bei 905MtC/a liegt, f{\"a}llt dieser Wert anschliessend bis zum Jahre 2050 auf 118 MtC/a. Bei Extrapolation dieser Dynamik in die Zukunft k{\"o}nnen wir annehmen, daß am Ende des 21. Jahrhunderts die \“urbane\” C-Gesamtbilanz Null bzw. negative Werte erreicht.},
  language  = {en}
}
@article{WrightUlkeFontetal.2020,
  author    = {Wright, Stephanie L. and Ulke, Jannis and Font, Anna and Chan, Ka Lung Andrew and Kelly, Frank J.},
  title     = {Atmospheric microplastic deposition in an urban environment and an evaluation of transport},
  series = {Environment international},
  volume    = {136},
  journal   = {Environment international},
  publisher = {Elsevier, Pergamon Press},
  address   = {New York, NY [u.a.]},
  issn      = {0160-4120},
  doi       = {10.1016/j.envint.2019.105411},
  pages     = {7},
  year      = {2020},
  abstract  = {Microplastics are a global environmental issue contaminating aquatic and terrestrial environments. They have been reported in atmospheric deposition, and indoor and outdoor air, raising concern for public health due to the potential for exposure. Moreover, the atmosphere presents a new vehicle for microplastics to enter the wider environment, yet our knowledge of the quantities, characteristics and pathways of airborne microplastics is sparse. Here we show microplastics in atmospheric deposition in a major population centre, central London. Microplastics were found in all samples, with deposition rates ranging from 575 to 1008 microplastics/m(2)/d. They were found in various shapes, of which fibrous microplastics accounted for the great majority (92\%). Across all samples, 15 different petrochemical-based polymers were identified. Bivariate polar plots indicated dependency on wind, with different source areas for fibrous and non-fibrous airborne microplastics. This is the first evidence of airborne microplastics in London and confirms the need to include airborne pathways when consolidating microplastic impacts on the wider environment and human health.},
  language  = {en}
}