Browsing by Subject "URBAN"

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  • Cavalli, F.; Alastuey, A.; Areskoug, H.; Ceburnis, D.; Cech, J.; Genberg, J.; Harrison, R. M.; Jaffrezo, J. L.; Kiss, G.; Laj, P.; Mihalopoulos, N.; Perez, N.; Quincey, P.; Schwarz, J.; Sellegri, K.; Spindler, G.; Swietlicki, E.; Theodosi, C.; Yttri, K. E.; Aas, W.; Putaud, J. P. (2016)
    Although particulate organic and elemental carbon (OC and EC) are important constituents of the suspended atmospheric particulate matter (PM), measurements of OC and EC are much less common and More uncertain than measurements of e.g. the ionic components of PM. In the framework of atmospheric research infrastructures supported by the European Union, actions have been undertaken to determine and mitigate sampling artefacts, and assess the comparability of OC and EC data obtained in a network of 10 atmospheric observatories across Europe. Positive sampling artefacts (from 0:4 to 2.8 mu g C/m(3)) and analytical discrepancies (between -50% and +40% for the EC/TC ratio) have been taken into account to generate a robust data set, from which we established the phenomenology of carbonaceous aerosols at regional background sites in Europe. Across the network, TC and EC annual average concentrations range from 0.4 to 9 mu g C/m(3), and from 0.1 to 2 mu g C/m(3), respectively. TC/PM10 annual mean ratios range from 0.11 at a Mediterranean site to 0.34 at the most polluted continental site, and TC/PM2.5 ratios are slightly greater at all sites (0.15-0.42). EC/TC annual mean ratios range from 0.10 to 0.22, and do not depend much on PM concentration levels, especially in winter. Seasonal variations in PM and TC concentrations, and in TC/PM and EC/TC ratios, differ across the network, which can be explained by seasonal changes in PM source contributions at some sites. (C) 2016 The Authors. Published by Elsevier Ltd.
  • Sokhi, Ranjeet S.; Singh, Vikas; Querol, Xavier; Finardi, Sandro; Targino, Admir Creso; Andrade, Maria de Fatima; Pavlovic, Radenko; Garland, Rebecca M.; Massague, Jordi; Kong, Shaofei; Baklanov, Alexander; Ren, Lu; Tarasova, Oksana; Carmichael, Greg; Peuch, Vincent-Henri; Anand, Vrinda; Arbilla, Graciela; Badali, Kaitlin; Beig, Gufran; Carlos Belalcazar, Luis; Bolignano, Andrea; Brimblecombe, Peter; Camacho, Patricia; Casallas, Alejandro; Charland, Jean-Pierre; Choi, Jason; Chourdakis, Eleftherios; Coll, Isabelle; Collins, Marty; Cyrys, Josef; da Silva, Cleyton Martins; Di Giosa, Alessandro Domenico; Di Leo, Anna; Ferro, Camilo; Gavidia-Calderon, Mario; Gayen, Amiya; Ginzburg, Alexander; Godefroy, Fabrice; Alexandra Gonzalez, Yuri; Guevara-Luna, Marco; Haque, Sk Mafizul; Havenga, Henno; Herod, Dennis; Horrak, Urmas; Hussein, Tareq; Ibarra, Sergio; Jaimes, Monica; Kaasik, Marko; Kousa, Anu; Kukkonen, Jaakko; Kulmala, Markku; Kuula, Joel; Petäjä, Tuukka (2021)
    This global study, which has been coordinated by the World Meteorological Organization Global Atmospheric Watch (WMO/GAW) programme, aims to understand the behaviour of key air pollutant species during the COVID-19 pandemic period of exceptionally low emissions across the globe. We investigated the effects of the differences in both emissions and regional and local meteorology in 2020 compared with the period 2015-2019. By adopting a globally consistent approach, this comprehensive observational analysis focuses on changes in air quality in and around cities across the globe for the following air pollutants PM2.5, PM10, PMC (coarse fraction of PM), NO2, SO2, NOx, CO, O-3 and the total gaseous oxidant (O-X = NO2 + O-3) during the pre-lockdown, partial lockdown, full lockdown and two relaxation periods spanning from January to September 2020. The analysis is based on in situ ground-based air quality observations at over 540 traffic, background and rural stations, from 63 cities and covering 25 countries over seven geographical regions of the world. Anomalies in the air pollutant concentrations (increases or decreases during 2020 periods compared to equivalent 2015-2019 periods) were calculated and the possible effects of meteorological conditions were analysed by computing anomalies from ERA5 reanalyses and local observations for these periods. We observed a positive correlation between the reductions in NO2 and NOx concentrations and peoples' mobility for most cities. A correlation between PMC and mobility changes was also seen for some Asian and South American cities. A clear signal was not observed for other pollutants, suggesting that sources besides vehicular emissions also substantially contributed to the change in air quality. As a global and regional overview of the changes in ambient concentrations of key air quality species, we observed decreases of up to about 70% in mean NO2 and between 30% and 40% in mean PM2.5 concentrations over 2020 full lockdown compared to the same period in 2015-2019. However, PM2.5 exhibited complex signals, even within the same region, with increases in some Spanish cities, attributed mainly to the long-range transport of African dust and/or biomass burning (corroborated with the analysis of NO2/CO ratio). Some Chinese cities showed similar increases in PM2.5 during the lockdown periods, but in this case, it was likely due to secondary PM formation. Changes in O-3 concentrations were highly heterogeneous, with no overall change or small increases (as in the case of Europe), and positive anomalies of 25% and 30% in East Asia and South America, respectively, with Colombia showing the largest positive anomaly of similar to 70%. The SO2 anomalies were negative for 2020 compared to 2015-2019 (between similar to 25 to 60%) for all regions. For CO, negative anomalies were observed for all regions with the largest decrease for South America of up to similar to 40%. The NO2/CO ratio indicated that specific sites (such as those in Spanish cities) were affected by biomass burning plumes, which outweighed the NO2 decrease due to the general reduction in mobility (ratio of similar to 60%). Analysis of the total oxidant (OX = NO2 + O-3) showed that primary NO2 emissions at urban locations were greater than the O-3 production, whereas at background sites, O-X was mostly driven by the regional contributions rather than local NO2 and O-3 concentrations. The present study clearly highlights the importance of meteorology and episodic contributions (e.g., from dust, domestic, agricultural biomass burning and crop fertilizing) when analysing air quality in and around cities even during large emissions reductions. There is still the need to better understand how the chemical responses of secondary pollutants to emission change under complex meteorological conditions, along with climate change and socio-economic drivers may affect future air quality. The implications for regional and global policies are also significant, as our study clearly indicates that PM2.5 concentrations would not likely meet the World Health Organization guidelines in many parts of the world, despite the drastic reductions in mobility. Consequently, revisions of air quality regulation (e.g., the Gothenburg Protocol) with more ambitious targets that are specific to the different regions of the world may well be required.
  • MacGregor-Fors, Ian; Falfan, Ina; Garcia-Arroyo, Michelle; Lemoine-Rodriguez, Richard; Gomez-Martinez, Miguel A.; Marin-Gomez, Oscar H.; Perez-Maqueo, Octavio; Equihua, Miguel (2022)
    To tackle urban heterogeneity and complexity, several indices have been proposed, commonly aiming to provide information for decision-makers. In this study, we propose a novel and customizable procedure for quantifying urban ecosystem integrity. Based on a citywide approach, we developed an easy-to-use index that contrasts physical and biological variables of urban ecosystems with a given reference system. The Urban Ecosystem Integrity Index (UEII) is the sum of the averages from the variables that make up its intensity of urbanization and biological components. We applied the UEII in a Mexican tropical city using land surface temperature, built cover, and the richness of native plants and birds. The overall ecosystem integrity of the city, having montane cloud, tropical dry, and temperate forests as reference systems, was low (-0.34 +/- SD 0.32), showing that, beyond its biodiverse greenspace network, the built-up structure highly differs from the ecosystems of reference. The UEII showed to be a flexible and easy-to-calculate tool to evaluate ecosystem integrity for cities, allowing for comparisons between or among cities, as well as the sectors/regions within cities. If used properly, the index could become a useful tool for decision making and resource allocation at a city level.
  • Arteaga, Alba; Malumbres-Olarte, Jagoba; Gabriel, Rosalina; Ros-Prieto, Alejandra; Casimiro, Pedro; Sanchez, Ana Fuentes; Albergaria, Isabel S.; Borges, Paulo A. V. (2020)
    The aim of our study was to characterise and compare the richness and composition of endemic, native (non-endemic) and introduced arthropod assemblages of two Azorean Historic Gardens with contrasting plant species composition. We hypothesised that Faial Botanic Garden would hold higher arthropod diversity and abundance of native and endemic arthropod species due to its larger native plant community. Species were collected using several arthropod standardised techniques between April 2017 and June 2018. We used the alpha diversity metrics (Hill series) and the partitioning of total beta diversity (beta(total)) into its replacement (beta(repl)) and richness (beta(rich)) components, to analyse the adult and total arthropod community. The orders Araneae, Coleoptera and Hemiptera were also studied separately. Our results show that the number of exotic arthropod species exceeds the number of native and/or the endemic species in both gardens, but the arthropod community of Faial Botanic Garden exhibited a higher density of endemic and native species. Despite some minor exceptions, the geographic origins of plant communities largely influenced the arthropod species sampled in each garden. This study improves our knowledge about urban arthropod diversity in the Azores and shows how well-designed urban garden management and planning contribute to the conservation of native and endemic Azorean species.
  • Cinderby, Steve; Archer, Diane; Mehta, Vishal K.; Neale, Chris; Opiyo, Romanus; Pateman, Rachel M.; Muhoza, Cassilde; Adelina, Charrlotte; Tuhkanen, Heidi (2021)
    To ensure future sustainability, cities need to consider concepts of livability and resident wellbeing alongside environmental, economic and infrastructure development equity. The current rapid urbanization experienced in many regions is leading to sustainability challenges, but also offers the opportunity to deliver infrastructure supporting the social aspects of cities and the services that underpin them alongside economic growth. Unfortunately, evidence of what is needed to deliver urban wellbeing is largely absent from the global south. This paper contributes to filling this knowledge gap through a novel interdisciplinary mixed methods study undertaken in two rapidly changing cities (one Thai and one Kenyan) using qualitative surveys, subjective wellbeing and stress measurements, and spatial analysis of urban infrastructure distribution. We find the absence of basic infrastructure (including waste removal, water availability and quality) unsurprisingly causes significant stress for city residents. However, once these services are in place, smaller variations (inequalities) in social (crime, tenure) and environmental (noise, air quality) conditions begin to play a greater role in determining differences in subjective wellbeing across a city. Our results indicate that spending time in urban greenspaces can mitigate the stressful impacts of city living even for residents of informal neighborhoods. Our data also highlights the importance of places that enable social interactions supporting wellbeing-whether green or built. These results demonstrate the need for diversity and equity in the provision of public realm spaces to ensure social and spatial justice. These findings strengthen the need to promote long term livability in LMIC urban planning alongside economic growth, environmental sustainability, and resilience.
  • Turoma, Sanna; Ratilainen, Saara; Trubina, Elena (2018)
    This special issue originates from a transnational collaboration of scholars in philology, comparative literature, social theory, sociology, anthropology, ethnography, and media studies. The collection strives to advance a research agenda built on the nexus of three intellectual and academic domains: post-Soviet Russian cultural studies', the research paradigm put forward by Cultural Studies, as well as empirical methods developed in sociology. The collection illustrates the importance of expanding the experience of Cultural Studies beyond its established spheres of national investigation, while it also speaks to the necessity to re-evaluate the hegemony of the English-language academic and cultural production on the global scale. The collection offers insights into the gamut of cultural practices and institutional environments in which Russian cultural production happens today. It shows how cultural industries and institutions in Russia are integrated into the global marketplace and transnational communities, while they also draw on and contribute to local lives and experiences by trying to create an autonomous space for symbolic production at personal and collective levels. Through diverse topics, the issue sheds light on the agency, i.e. practitioners and participants, creators and consumers, of Russian cultural production and the neoliberal practices implemented on creative work and cultural administration in Russia today. The Introduction outlines the development of academic studies on Russian cultural practices since 1991; describes main political developments shaping the cultural field in Putin's Russia; and, finally, identifies the Cultural Studies debates the editors of the collection find most productive for investigations of Russia, i.e. the instrumentalization of culture and culture as resource. Relocated in an analysis of a post-socialist society, these conceptualisations seem increasingly problematic in a situation where local and federal policies governing cultural and creative work focus simultaneously on marketization and on nationalism as the main tools of legitimizing the federal government.
  • Moen, Gro Kvelprud; Ordiz, Andres; Kindberg, Jonas; Swenson, Jon E.; Sundell, Janne; Stoen, Ole-Gunnar (2019)
    Human disturbance causes behavioral responses in wildlife, including large carnivores. Previous research in Scandinavia has documented that brown bears (Ursus arctos) show a variety of behavioral reactions to different human activities. We investigated how proximity to human settlements and roads, as proxies of human influence, affected brown bears' reactions to encountering humans. We analyzed experimental approaches to GPS collared bears, 18 males and 23 single females, in Sweden (n = 148 approaches) and Finland (n = 33), conducted between 2004 and 2012. The bears in Finland inhabited areas with higher human density compared to Sweden. However, the proportion of bears staying or moving when approached and the flight initiation distances were similar in both countries. In Sweden, the flight responses were not dependent on human densities or roads inside the bears' home ranges or the distances from the bears to roads and settlements. Brown bears in Fennoscandia live in areas with relatively low human population densities, but in many areas with high forestry road densities. Our results show that bears' flight reactions were consistent between areas, which is an important message for management, reinforcing previous studies that have documented human avoidance by bears at different spatial and temporal scales.
  • Asplund , Therese; Neset, Tina-Simone; Käyhkö, Janina; Wiréhn, Lotten; Juhola, Sirkku (2019)
    The use of digital tools and interactive technologies for farming systems has increased rapidly in recent years and is likely to continue to play a significant role in meeting future challenges. Particularly games and gaming are promising new and innovative communication strategies to inform and engage public and stakeholders with scientific research. This study offers an analysis of how a research based game on climate change maladaptation can support, but also hinder players’ sense-making processes. Through the analysis of eight gaming workshops, this study identifies challenges and support for the players’ sense-making. While it concludes that conceptual thinking of game content sometimes clashes with players’ everyday experiences and practice, possibly resulting in loss of credibility, this study also concludes that gaming may function as an eye-opener to new ways of thinking. Overall, this paper suggests that the communication of (social) science and agricultural practices through serious gaming has great potential but at the same time poses challenges due to different knowledge systems and interpretive frameworks among researchers and practitioners.
  • Quesada, J.; Chavez-Zichinelli, Carlos A.; Garcia-Arroyo, Michelle; Yeh, Pamela J.; Guevara, R.; Izquierdo-Palma, J.; MacGregor-Fors, I. (2022)
    Bold or shy? Examining the risk-taking behavior and neophobia of invasive and non-invasive house sparrows. Behavior provides a useful framework for understanding specialization, with animal personality aiding our understanding of the invasiveness of birds. Invasions imply dispersion into unknown areas and could require changes in behavior or spatial clustering based on personality. Reduced neophobia and increased exploring behavior could allow individuals to colonize new areas as they test and use non-familiar resources. Here, we hypothesized that house sparrow (Passer domesticus) individuals from invasive populations would exhibit bolder behavior than in non-invasive populations. We assessed risk taking and neophobia in male house sparrows in Barcelona (where it is considered native) and in Mexico City (where it has become widely invasive), captured in two different habitats, urban and non-urban. We assessed latency to enter an experimental cage and to explore it, and latency to feed and feeding time in the presence of a novel object. We found that sparrows from Mexico City, both from urban and non-urban areas, were quicker to enter the experimental cage than the sparrows from Barcelona. The time it took the birds to start exploring the cage gave a similar result. We found no differences between cities or habitats in the latency to feed and feeding time while exposed to a novel object. Our results partially support the view that the invader populations from Mexico City are bolder than those from Barcelona. Behavior is an important component of plasticity and its variability may have an important effect on adaptation to local situations. Future studies should disentangle the underlying mechanisms that explain the different personalities found in populations of different regions, contrasting populations of different densities, and taking different food availability scenarios into account.
  • Rummukainen, Olli; Radun, Jenni; Virtanen, Toni; Pulkki, Ville (2014)
  • Wang, Yonghong; Gao, Wenkang; Wang, Shuai; Song, Tao; Gong, Zhengyu; Ji, Dongsheng; Wang, Lili; Liu, Zirui; Tang, Guiqian; Huo, Yanfeng; Tian, Shili; Li, Jiayun; Li, Mingge; Yang, Yuan; Chu, Biwu; Petäjä, Tuukka; Kerminen, Veli-Matti; He, Hong; Hao, Jiming; Kulmala, Markku; Wang, Yuesi; Zhang, Yuanhang (2020)
    Although much attention has been paid to investigating and controlling air pollution in China, the trends of air-pollutant concentrations on a national scale have remained unclear. Here, we quantitatively investigated the variation of air pollutants in China using long-term comprehensive data sets from 2013 to 2017, during which Chinese government made major efforts to reduce anthropogenic emission in polluted regions. Our results show a significant decreasing trend in the PM2.5 concentration in heavily polluted regions of eastern China, with an annual decrease of similar to 7% compared with measurements in 2013. The measured decreased concentrations of SO2, NO2 and CO (a proxy for anthropogenic volatile organic compounds) could explain a large fraction of the decreased PM2.5 concentrations in different regions. As a consequence, the heavily polluted days decreased significantly in corresponding regions. Concentrations of organic aerosol, nitrate, sulfate, ammonium and chloride measured in urban Beijing revealed a remarkable reduction from 2013 to 2017, connecting the decreases in aerosol precursors with corresponding chemical components closely. However, surface-ozone concentrations showed increasing trends in most urban stations from 2013 to 2017, which indicates stronger photochemical pollution. The boundary-layer height in capital cities of eastern China showed no significant trends over the Beijing-Tianjin-Hebei, Yangtze River Delta and Pearl River Delta regions from 2013 to 2017, which confirmed the reduction in anthropogenic emissions. Our results demonstrated that the Chinese government was successful in the reduction of particulate matter in urban areas from 2013 to 2017, although the ozone concentration has increased significantly, suggesting a more complex mechanism of improving Chinese air quality in the future.
  • Lever, D.; Rush, L.V.; Thorogood, R.; Gotanda, K. M. (2022)
    Urbanization is rapidly changing ecological niches. On the inhabited Galapagos Islands, Darwin's finches consume human-introduced foods preferentially; however, it remains unclear why. Here, we presented pastry with flavour profiles typical of human foods (oily, salty and sweet) to small ground finches (Geospiza fuliginosa) and medium ground finches (Geospiza fortis) to test if latent taste preferences might drive the selection of human foods. If human food flavours were consumed more than a neutral or bitter control only at sites with human foods, then we predicted tastes were acquired after urbanization; however, if no site differences were found then this would indicate latent taste preferences. Contrary to both predictions, we found little evidence that human food flavours were preferred compared with control flavours at any site. Instead, finches showed a weak aversion to oily foods, but only at remote (no human foods present) sites. This was further supported by behavioural responses, with beak-wiping occurring more often at remote sites after finches tasted flavours associated with human foods. Our results suggest, therefore, that while Darwin's finches regularly exposed to human foods might have acquired a tolerance to human food flavours, latent taste preferences are unlikely to have played a major role in their dietary response to increased urbanization.
  • Fung, Pak Lun; Zaidan, Martha Arbayani; Surakhi, Ola; Tarkoma, Sasu; Petäjä, Tuukka; Hussein, Tareq (2021)
    In air quality research, often only size-integrated particle mass concentrations as indicators of aerosol particles are considered. However, the mass concentrations do not provide sufficient information to convey the full story of fractionated size distribution, in which the particles of different diameters (Dp) are able to deposit differently on respiratory system and cause various harm. Aerosol size distribution measurements rely on a variety of techniques to classify the aerosol size and measure the size distribution. From the raw data the ambient size distribution is determined utilising a suite of inversion algorithms. However, the inversion problem is quite often ill-posed and challenging to solve. Due to the instrumental insufficiency and inversion limitations, imputation methods for fractionated particle size distribution are of great significance to fill the missing gaps or negative values. The study at hand involves a merged particle size distribution, from a scanning mobility particle sizer (NanoSMPS) and an optical particle sizer (OPS) covering the aerosol size distributions from 0.01 to 0.42 µm (electrical mobility equivalent size) and 0.3 to 10 µm (optical equivalent size) and meteorological parameters collected at an urban background region in Amman, Jordan, in the period of 1 August 2016–31 July 2017. We develop and evaluate feed-forward neural network (FFNN) approaches to estimate number concentrations at particular size bin with (1) meteorological parameters, (2) number concentration at other size bins and (3) both of the above as input variables. Two layers with 10–15 neurons are found to be the optimal option. Worse performance is observed at the lower edge (0.01<Dp<0.02 µm), the mid-range region (0.15<Dp<0.5 µm) and the upper edge (6<Dp<10 µm). For the edges at both ends, the number of neighbouring size bins is limited, and the detection efficiency by the corresponding instruments is lower compared to the other size bins. A distinct performance drop over the overlapping mid-range region is due to the deficiency of a merging algorithm. Another plausible reason for the poorer performance for finer particles is that they are more effectively removed from the atmosphere compared to the coarser particles so that the relationships between the input variables and the small particles are more dynamic. An observable overestimation is also found in the early morning for ultrafine particles followed by a distinct underestimation before midday. In the winter, due to a possible sensor drift and interference artefacts, the estimation performance is not as good as the other seasons. The FFNN approach by meteorological parameters using 5 min data (R2= 0.22–0.58) shows poorer results than data with longer time resolution (R2= 0.66–0.77). The FFNN approach using the number concentration at the other size bins can serve as an alternative way to replace negative numbers in the size distribution raw dataset thanks to its high accuracy and reliability (R2= 0.97–1). This negative-number filling approach can maintain a symmetric distribution of errors and complement the existing ill-posed built-in algorithm in particle sizer instruments.
  • Fung, Pak L.; Zaidan, Martha A.; Timonen, Hilkka; Niemi, Jarkko V.; Kousa, Anu; Kuula, Joel; Luoma, Krista; Tarkoma, Sasu; Petäjä, Tuukka; Kulmala, Markku; Hussein, Tareq (2021)
    Air quality prediction with black-box (BB) modelling is gaining widespread interest in research and industry. This type of data-driven models work generally better in terms of accuracy but are limited to capture physical, chemical and meteorological processes and therefore accountability for interpretation. In this paper, we evaluated different white-box (WB) and BB methods that estimate atmospheric black carbon (BC) concentration by a suite of observations from the same measurement site. This study involves data in the period of 1st January 2017–31st December 2018 from two measurement sites, from a street canyon site in Mäkelänkatu and from an urban background site in Kumpula, in Helsinki, Finland. At the street canyon site, WB models performed (R² = 0.81–0.87) in a similar way as the BB models did (R² = 0.86–0.87). The overall performance of the BC concentration estimation methods at the urban background site was much worse probably because of a combination of smaller dynamic variability in the BC values and longer data gaps. However, the difference in WB (R²= 0.44–0.60) and BB models (R² = 0.41–0.64) was not significant. Furthermore, the WB models are closer to physics-based models, and it is easier to spot the relative importance of the predictor variable and determine if the model output makes sense. This feature outweighs slightly higher performance of some individual BB models, and inherently the WB models are a better choice due to their transparency in the model architecture. Among all the WB models, IAP and LASSO are recommended due to its flexibility and its efficiency, respectively. Our findings also ascertain the importance of temporal properties in statistical modelling. In the future, the developed BC estimation model could serve as a virtual sensor and complement the current air quality monitoring.
  • Abrego, Nerea; Crosier, Brittni; Somervuo, Panu; Ivanova, Natalia; Abrahamyan, Arusyak; Abdi, Amir; Hämäläinen, Karoliina; Junninen, Kaisa; Maunula, Minna; Purhonen, Jenna; Ovaskainen, Otso (2020)
    Increasing evidence suggests that degradation of biodiversity in human populated areas is a threat for the ecosystem processes that are relevant for human well-being. Fungi are a megadiverse kingdom that plays a key role in ecosystem processes and affects human well-being. How urbanization influences fungi has remained poorly understood, partially due to the methodological difficulties in comprehensively surveying fungi. Here we show that both aerial and soil fungal communities are greatly poorer in urban than in natural areas. Strikingly, a fivefold reduction in fungal DNA abundance took place in both air and soil samples already at 1 km scale when crossing the edge from natural to urban habitats. Furthermore, in the air, fungal diversity decreased with urbanization even more than in the soil. This result is counterintuitive as fungal spores are known to disperse over large distances. A large proportion of the fungi detectable in the air are specialized to natural habitats, whereas soil fungal communities comprise a large proportion of habitat generalists. The sensitivity of the aerial fungal community to anthropogenic disturbance makes this method a reliable and efficient bioindicator of ecosystem health in urban areas.
  • Valdes-Correcher, Elena; Popova, Anna; Galman, Andrea; Prinzing, Andreas; Selikhovkin, Andrey; Howe, Andy G.; Mrazova, Anna; Dulaurent, Anne-Maimiti; Hampe, Arndt; Tack, Ayco Jerome Michel; Bouget, Christophe; Lupastean, Daniela; Harvey, Deborah; Musolin, Dmitry L.; Lovei, Gabor L.; Centenaro, Giada; Van Halder, Inge; Hagge, Jonas; Dobrosavljevic, Jovan; Pitkänen, Juha-Matti; Koricheva, Julia; Sam, Katerina; Barbaro, Luc; Branco, Manuela; Ferrante, Marco; Faticov, Maria; Tahadlova, Marketa; Gossner, Martin; Cauchoix, Maxime; Bogdziewicz, Michal; Duduman, Mihai-Leonard; Kozlov, Mikhail; Bjoern, Mona C.; Mamaev, Nikita A.; Fernandez-Conradi, Pilar; Thomas, Rebecca L.; Wetherbee, Ross; Green, Samantha; Milanovic, Slobodan; Moreira, Xoaquin; Mellerin, Yannick; Kadiri, Yasmine; Castagneyrol, Bastien (2022)
    Urbanization is an important driver of the diversity and abundance of tree-associated insect herbivores, but its consequences for insect herbivory are poorly understood. A likely source of variability among studies is the insufficient consideration of intra-urban variability in forest cover. With the help of citizen scientists, we investigated the independent and interactive effects of local canopy cover and percentage of impervious surface on insect herbivory in the pedunculate oak (Quercus robur L.) throughout most of its geographic range in Europe. We found that the damage caused by chewing insect herbivores as well as the incidence of leaf-mining and gall-inducing herbivores consistently decreased with increasing impervious surface around focal oaks. Herbivory by chewing herbivores increased with increasing forest cover, regardless of impervious surface. In contrast, an increase in local canopy cover buffered the negative effect of impervious surface on leaf miners and strengthened its effect on gall inducers. These results show that-just like in non-urban areas-plant-herbivore interactions in cities are structured by a complex set of interacting factors. This highlights that local habitat characteristics within cities have the potential to attenuate or modify the effect of impervious surfaces on biotic interactions.
  • Lin, Brenda B.; Ossola, Alessandro; Alberti, Marina; Andersson, Erik; Bai, Xuemei; Dobbs, Cynnamon; Elmqvist, Thomas; Evans, Karl L.; Frantzeskaki, Niki; Fuller, Richard A.; Gaston, Kevin J.; Haase, Dagmar; Jim, Chi Yung; Konijnendijk, Cecil; Nagendra, Harini; Niemelä, Jari; McPhearson, Timon; Moomaw, William R.; Parnell, Susan; Pataki, Diane; Ripple, William J.; Tan, Puay Yok (2021)
    Record climate extremes are reducing urban liveability, compounding inequality, and threatening infrastructure. Adaptation measures that integrate technological, nature-based, and social solutions can provide multiple co-benefits to address complex socioecological issues in cities while increasing resilience to potential impacts. However, there remain many challenges to developing and implementing integrated solutions. In this Viewpoint, we consider the value of integrating across the three solution sets, the challenges and potential enablers for integrating solution sets, and present examples of challenges and adopted solutions in three cities with different urban contexts and climates (Freiburg, Germany; Durban, South Africa; and Singapore). We conclude with a discussion of research directions and provide a road map to identify the actions that enable successful implementation of integrated climate solutions. We highlight the need for more systematic research that targets enabling environments for integration; achieving integrated solutions in different contexts to avoid maladaptation; simultaneously improving liveability, sustainability, and equality; and replicating via transfer and scale-up of local solutions. Cities in systematically disadvantaged countries (sometimes referred to as the Global South) are central to future urban development and must be prioritised. Helping decision makers and communities understand the potential opportunities associated with integrated solutions for climate change will encourage urgent and deliberate strides towards adapting cities to the dynamic climate reality.
  • Jokela, Markus (2020)
    Neighborhood characteristics have been associated with psychological distress, but it is uncertain whether these associations are causal. The current article reviews data from interventions and quasi-experimental studies that have addressed the question of causality of neighborhood associations. Overall, data from neighborhood interventions, longitudinal studies, and twin studies have provided only limited and inconsistent evidence to support causal interpretation of neighborhood associations with psychological distress: very few findings have been replicated across different samples, and many associations have been observed only with some of the multiple measures included the studies. Studies that examine the effects of neighborhood change on people's wellbeing are needed to improve causal inference and policy relevance of neighborhood studies.
  • Rovira, J.; Paredes-Ahumada, J. A.; Barceló-Ordinas, J. M.; García-Vidal, J.; Reche, C.; Sola, Y.; Fung, Pak Lun; Petäjä, Tuukka; Hussein, Tareq; Viana, Mar (2022)
    Black carbon (BC) is a product of incomplete combustion, present in urban aerosols and sourcing mainly from road traffic. Epidemiological evidence reports positive associations between BC and cardiovascular and respiratory disease. Despite this, BC is currently not regulated by the EU Air Quality Directive, and as a result BC data are not available in urban areas from reference air quality monitoring networks in many countries. To fill this gap, a machine learning approach is proposed to develop a BC proxy using air pollution datasets as an input. The proposed BC proxy is based on two machine learning models, support vector regression (SVR) and random forest (RF), using observations of particle mass and number concentrations (N), gaseous pollutants and meteorological variables as the input. Experimental data were collected from a reference station in Barcelona (Spain) over a 2-year period (2018–2019). Two months of additional data were available from a second urban site in Barcelona, for model validation. BC concentrations estimated by SVR showed a high degree of correlation with the measured BC concentrations (R2 = 0.828) with a relatively low error (RMSE = 0.48 μg/m3). Model performance was dependent on seasonality and time of the day, due to the influence of new particle formation events. When validated at the second station, performance indicators decreased (R2 = 0.633; RMSE = 1.19 μg/m3) due to the lack of N data and PM2.5 and the smaller size of the dataset (2 months). New particle formation events critically impacted model performance, suggesting that its application would be optimal in environments where traffic is the main source of ultrafine particles. Due to its flexibility, it is concluded that the model can act as a BC proxy, even based on EU-regulatory air quality parameters only, to complement experimental measurements for exposure assessment in urban areas.
  • Pena-Peniche, Alexander; Mota-Vargas, Claudio; Garcia-Arroyo, Michelle; MacGregor-Fors, Ian (2021)
    Biological invasions occur when individuals of alien species establish and colonize new locations. The House Sparrow (Passer domesticus) is one of the most widespread invasive birds, native to Eurasia and North Africa, and has successfully invaded many regions from across the world. The House Sparrow was successfully introduced in 1852 into North America and quickly invaded most of the North American continent, except the Florida Peninsula. Currently, the species is found throughout agricultural and urban landscapes of North America except the Yucatan Peninsula. We analyzed the invasion process of the House Sparrow in order to determine why it is absent from the Yucatan Peninsula. For this, we focused our assessment on historical records of the species together with climatic variables. Using an ordination analysis, we compared the climatic space of the North American records for the House Sparrow with that of the Yucatan Peninsula, as well as those before and after the Florida Peninsula invasion, which took sparrows longer to fully colonize. We found that climate may represent an important driver in the process of invasion in the North American invasion of House Sparrows, probably delaying the Florida invasion, and so far, preventing the Yucatan Peninsula invasion. Our results suggest that the absence of the House Sparrow in the Yucatan Peninsula could be a temporal delay, as occurred in the Florida Peninsula; yet, climatic conditions in the Yucatan Peninsula show important differences from those of the Florida Peninsula. Given the species' plasticity and generalist life history traits, it is possible that the House Sparrow may overcome present climatic restrictions and invade the Yucatan Peninsula if proper management is not set in action.