Ecology for Future Cities

• INT14 • Why should we study urban ecosystems? > S. Sébastien BAROT
Content : Talk 1. Sébastien BAROT*, Sébastien Barot, director of research, Sorbonne Université, France, sebastien.barot@ird.fr

Abstract: Ecologists have historically started to study natural ecosystems such as forests and species that could be considered independent from human influence. They are now more and more tackling issues linked to the interactions between human societies and biodiversity, in particular in urban environments. This has led to an explosion of publications in urban ecology since 2005. This talk aims at explaining this trend and at suggesting some consequences for the development of ecological sciences. Obviously, the development of urban ecology is linked to (1) the worldwide development of cities and the fact that the proportion of humans living in cities is increasing and is now over 50%, (2) the awareness that cities have a strong negative impact on the biosphere because they concentrate the consumption of resources and sources of pollution, (3) a new awareness of the presence of biodiversity within cities. This leads to very diverse studies pertaining to all sub-fields of ecology from behavioural and evolutionary ecology to functional and ecosystem ecology. Overall, three main themes emerge: (1) the impact of urban environments on biodiversity, (2) the impact of these environments on the functioning of urban ecosystems, (3) more integrated studies analysing the tight interactions between humans and biodiversity in urban contexts. This encompasses the impact of urban ecosystems on city dwellers (through ecosystem services) and all processes determining the feedbacks to urban biodiversity. This also encompasses the development of ecological engineering within towns. In this way, urban ecology goes along with the development of studies on socio-ecosystems that marks the recent history of ecology and that requires undertaking interdisciplinary programs mixing natural sciences, human sciences and involving stakeholders. This is necessary to push towards more sustainable relations between human societies and the biosphere. • INT31 • Urbanisation globally reduces functional diversity across multiple taxa > M. Marco MORETTI
Content : Talk 2. Marco MORETTI, research group leader, Swiss Federal Research Institute WSL, Switzerland, marco.moretti@wsl.ch

Bertrand FOURNIER, Potsdam University, Germany; Amy K. HAHS, The University of Melbourne, Australia; Myla F. J. ARONSON, Rutgers, The State University of New Jersey, USA; Charles NILON, University of Missouri, USA; Sonja KNAPP, Helmholtz-Centre for Environmental Research UFZ, Technische Universität Berlin TUB, German Centre for Integrative Biodiversity Research iDiv, Halle-Jena-Leipzig; Johan KOTZE, University of Helsinki, Finland.

Abstract: Cities can host significant biological diversity. Yet, urbanisation leads to the loss of habitats and, potentially, to local extinctions. Understanding how multiple taxa respond to urbanisation globally is essential to promote biodiversity conservation in cities. Using an unprecedented dataset with site-level occurrence and trait data of 5,302 species from six taxonomic groups (amphibians, bats, bees, birds, carabid beetles, and reptiles) across 379 cities on 6 continents, we investigate how urbanisation shapes the community trait-composition and diversity across the globe. We show that urbanisation affects community functional diversity globally through taxon-specific changes in trait composition leading to a contraction of trait space across taxa. Urbanisation impacts all traits, with traits related to reproductive strategy and mobility consistently showing the strongest response. The effect of urbanisation on community trait composition is important across all taxa and, in birds and reptiles, exceeds that of latitude and climate. As functional diversity is linked to the resilience of ecological systems, the observed contraction of trait space threatens the capacity of urban environments to respond to challenges such as climate change, further habitat loss, and other disruptions. Maximising functional diversity within and among cities should thus become pivotal in conservation and management programmes. • INT32 • Adaptation of plants and ecologists to urban environments > A. Audrey MURATET
Content : Talk 3. Audrey MURATET*, lecturer, Institut de Botanique, Faculté des sciences de la vie, Université de Strasbourg, France, amuratet@unistra.fr;

Laurent HARDION, Laboratoire Image Ville Environnement, University of Strasbourg, CNRS; Kenji FUJIKI, Laboratoire Image Ville Environnement, University of Strasbourg, CNRS; Adine HECTOR, Eurométropole de Strasbourg; Pierre-Alexis HERRAULT, Laboratoire Image Ville Environnement, University of Strasbourg, CNRS; Etienne CHANEZ, Laboratoire Image Ville Environnement, University of Strasbourg, CNRS; Anne PUISSANT, Laboratoire Image Ville Environnement, University of Strasbourg, CNRS.

Research in urban ecology progressed since the 1970’s, especially to describe animals and plants response patterns to urbanization based essentially on taxonomic approaches, quantifying the number and abundance of species. This research was also very restricted to describe the heterogeneity of cities along built gradients. We propose to complete these researches by carrying out an analysis of the city integrating, in addition to its built characteristics, its natural, environmental and human characteristics and, by associating to the taxonomic approach, functional and evolutionary ones. Our objective is to understand the adaptation mechanisms - underlying the observed patterns - of plant communities and populations to the urban environment. We question the relative role of genetic adaptation, phenotypic plasticity or rearrangement of plants populations and communities in the face of urbanization. During three years, we studied the composition of plant communities and measured the functional traits of 4 species populations - Dactylis glomerata, Plantago lanceolata, Trifolium pratense and Medicago lupulina - in 60 herbaceous sites located in the Eurometropole of Strasbourg and exposed to varying pressures of artificialization, human management and population density. At the community level, we studied the response of performance, trait and diversity indices to urbanization. At the population level, we studied a selection of plant traits characterising growth, reproduction and survival functions of an individual. The intraspecific variabilities observed in situ were compared to an approach under similar environmental conditions in a botanical garden, to disentangle adaptation mechanisms related to genetic adaptation from those related to phenotypic plasticity. We combine our skills of community ecologist, population biologist, human and physical geographers and, stakeholders to encourage better consideration of biodiversity in the management of green spaces and the development of cities. • INT33 • How to make cities more biodiverse? > N. Nathalie MACHON
Content : Tak 4. Nathalie MACHON*, professor and director, Muséum National d'Histoire Naturelle, Paris, France, nathalie.machon@mnhn.fr

Abstract: As cities spread over ever larger areas of the globe, they increasingly occupy the habitats of wild species. What had little impact when cities were small is no longer the case in today's megacities. The result is a loss of biodiversity in highly urbanised areas. The damages to biodiversity are problematic for the ecology of the planet and question the stability and adaptability of the biosphere in the future. The impact on human life is also considerable. The quality of life and health of city dwellers are threatened by the poverty of biodiversity in the city. Through the benefits produced by the urban ecosystem, biodiversity makes the city more habitable for city dwellers and enables it to adapt to the climate changes affecting the world. Consequently, managers of urban territories must find ways to restore biodiversity in the densest districts. This presentation will outline measures to implement to improve the quality of nature in cities. These measures are based on the following three rules: numerous, large and diversified green spaces for biodiversity, soft management and corridors between green spaces. The challenge is particularly difficult because it has to conciliate urban densification with preservation of good quality nature areas. • INT34 • Animal-aided design for biophilic cities > W. Wolfgang WEISSER
Content : Talk 6. Wolfgang WEISSER*, professor, Technical University of Munich, TUM School of Life Sciences, Germany, wolfgang.weisser@tum.de;

Thomas HAUCK, professor, Vienna University of Technology, Institute of Urban Design and Landscape Architecture, Department of Landscape Architecture, thomas.hauck@tuwien.ac.at

Abstract: Green infrastructure planning aims to increase urban biodiversity and ecosystem services, but in the urban planning practice, success is limited, because biodiversity is not well- integrated into current urban planning procedures. This is true in particular for urban wildlife, with the consequence that even species that would be able to live in cities are not present or declining. Animal-Aided Design is a methodology that has been developed to allow the integration of animal species into urban planning procedures. In the talk we review our experiences of applying Animal-Aided Design in practice to a range of projects, mostly object planning. We identify common challenges for wildlife-inclusive urban design that result from a) building sector professionals not feeling responsible for planning for wildlife, b) a lack of awareness of animal needs, and c) the limited ability of actors to find integrative solutions for humans and wildlife. Urban ecology can help addressing these challenges, by developing tangible solutions that help designers to address the needs of wildlife, and that are integrative by also addressing the needs of humans. This requires urban ecology to develop a deeper understanding of how animals appropriate human-made structures in the urban environment. • INT35 • Nature's contributions to people in cities: What have we learned from two years in a pandemic? > L. Leonie K FISCHER
Content : Talk 5. Leonie FISCHER*, professor, Universität Stuttgart, Germany, leonie.fischer@ilpoe.uni-stuttgart.de

Nature is a requisite for good living outside and inside cities, with direct and indirect contributions to people’s wellbeing and desires – and now, more than two years in a pandemic seemed to have given more people an understanding of these values. Before the pandemic, many elements of urban green and urban biodiversity itself have been the focus of urban ecological studies, with formal green areas and their contributions to people being well researched. Yet, the pandemic times now unveiled also some hidden contributions and ecological functions of informal and “uncommon” green places, structures or elements. In our research both in the Global North and South, we looked specifically at all-day places such as streetscapes and balconies, where people were able to spent time outdoors and connect to some sort of urban greenery, including the potted herb on a window sill, the mango picked from a tree alongside the road or a wild-growing shade tree in the otherwise sealed courtyard. Beside many social and cultural benefits of such green places or elements for people, we also detected changes in their use of natural elements and their nature interaction, and a higher awareness of nature’s contributions to their all-day life, spanning from livelihood contributions to stress relief and joy. Beside results from our several case studies during the pandemic around the world, this talk will include first insights from a systematic review on the effects of the COVID-19 pandemic on the use of urban greenspace. Following, I will argue in my talk that we now need to link the recent urban ecological insights with practical approaches of other disciplines such as urban planning and sustainable architecture to contribute to the functioning of future cities.