Shifting forward: Urban ecology in perspective.

The world has become urban; cities increasingly shape our worldviews, relation to other species, and the large-scale, long-term decisions we make. Cities are nature, but they need to align better with other ecosystems to avoid accelerating climate change and loss of biodiversity. We need a science to guide urban development across the diverse realities of global cities. This need can be met, in part, by shifts in urban ecology and its linkages to related sciences. This perspective is a "synthesis of syntheses", consolidating ideas from the other articles in the Special Section. It re-examines the role of urban ecology, and explores its integration with other disciplines that study cities. We conclude by summarizing the next steps in the ongoing shift in urban ecology, which is fast becoming an integral part of urban studies.

The relational shift in urban ecology: From place and structures to multiple modes of coproduction for positive urban futures.

This perspective emerged from ongoing dialogue among ecologists initiated by a virtual workshop in 2021. A transdisciplinary group of researchers and practitioners conclude that urban ecology as a science can better contribute to positive futures by focusing on relationships, rather than prioritizing urban structures. Insights from other relational disciplines, such as political ecology, governance, urban design, and conservation also contribute. Relationality is especially powerful given the need to rapidly adapt to the changing social and biophysical drivers of global urban systems. These unprecedented dynamics are better understood through a relational lens than traditional structural questions. We use three kinds of coproduction-of the social-ecological world, of science, and of actionable knowledge-to identify key processes of coproduction within urban places. Connectivity is crucial to relational urban ecology. Eight themes emerge from the joint explorations of the paper and point toward social action for improving life and environment in urban futures.

A transformative shift in urban ecology toward a more active and relevant future for the field and for cities.

This paper builds on the expansion of urban ecology from a biologically based discipline-ecology in the city-to an increasingly interdisciplinary field-ecology of the city-to a transdisciplinary, knowledge to action endeavor-an ecology for and with the city. We build on this "prepositional journey" by proposing a transformative shift in urban ecology, and we present a framework for how the field may continue this shift. We conceptualize that urban ecology is in a state of flux, and that this shift is needed to transform urban ecology into a more engaged and action based field, and one that includes a diversity of actors willing to participate in the future of their cities. In this transformative shift, these actors will engage, collaborate, and participate in a continuous spiral of knowledge → action → knowledge spiral and back to knowledge loop, with the goal of co producing sustainable and resilient solutions to myriad urban challenges. Our framework for this transformative shift includes three pathways: (1) a repeating knowledge → action → knowledge spiral of ideas, information, and solutions produced by a diverse community of agents of urban change working together in an "urban sandbox"; (2) incorporation of a social-ecological-technological systems framework in this spiral and expanding the spiral temporally to include the "deep future," where future scenarios are based on a visioning of seemingly unimaginable or plausible future states of cities that are sustainable and resilient; and (3) the expansion of the spiral in space, to include rural areas and places that are not yet cities. The three interrelated pathways that define the transformative shift demonstrate the power of an urban ecology that has moved beyond urban systems science and into a realm where collaborations among diverse knowledges and voices are working together to understand cities and what is urban while producing sustainable solutions to contemporary challenges and envisioning futures of socially, ecologically, and technologically resilient cities. We present case study examples of each of the three pathways that make up this transformative shift in urban ecology and discuss both limitations and opportunities for future research and action with this transdisciplinary broadening of the field.

Forging just ecologies: 25 years of urban long-term ecological research collaboration.

We ask how environmental justice and urban ecology have influenced one another over the past 25 years in the context of the US Long-Term Ecological Research (LTER) program and Baltimore Ecosystem Study (BES) project. BES began after environmental justice emerged through activism and scholarship in the 1980s but spans a period of increasing awareness among ecologists and environmental practitioners. The work in Baltimore provides a detailed example of how ecological research has been affected by a growing understanding of environmental justice. The shift shows how unjust environmental outcomes emerge and are reinforced over time by systemic discrimination and exclusion. We do not comprehensively review the literature on environmental justice in urban ecology but do present four brief cases from the Caribbean, Africa, and Asia, to illustrate the global relevance of the topic. The example cases demonstrate the necessity for continuous engagement with communities in addressing environmental problem solving.

Examining privilege and power in US urban parks and open space during the double crises of antiblack racism and COVID-19.

In this perspective, we argue that creating the positive outcomes socio-ecological researchers and practitioners seek for urban areas requires acknowledging and addressing the interactions of race and systemic racism in parks, open and green spaces. Racial experiences are inseparable from physical landscapes and the processes of designing, managing, or studying them. From COVID-19 to the Black Lives Matter movement and protests, the events of 2020 in the United States underscore how considerations of social justice must extend beyond the conventional distributional focus of environmental justice. It must incorporate an understanding of how the built environment is racialized spatially, but not always readily quantified through the proximity-based measurements frequently used in research and practice. The perspective is organized in three main parts. The first part presents a series of vignettes to frame the ways cities and individuals participate, respond, and interact under COVID-19 with racial segregation as the backdrop. The second part suggests a stepwise approach to building an understanding of racial inequities in socio-ecological systems (SES) research and practice including four entry points: (1) racialized spatial distribution of hazards and amenities, (2) racialized qualities of space, (3) racialized people in space, and (4) racialized creation of space. Finally, the third part proposes actions the SES community can take to enhance our commitment to community recovery, improvement, and thrivability. This perspective cautions practitioners and researchers against opportunistic or quick-fix solutions, and instead challenges our colleagues to be inclusive of disenfranchised voices in shaping socio-ecological goals, now more than ever. The goal of this perspective is to spark engagement with power and privilege in parks and open space using the example of COVID-19 and race in the US.

Leveraging ancillary benefits from urban greenspace - a case study of St. Louis, Missouri.

Urban greenspace and green infrastructure are often cited for their many ecosystem services and benefits including stormwater management. However, the localized nature and limited range of effects of these benefits and the type of greenspace and green infrastructure, make planning and placement critical components to selecting for and maximizing desired benefits. Here, the authors test a framework to demonstrate a practical approach to simultaneously manage excess stormwater and maximize distribution of ecosystem services to underserved areas using spatial analysis. St. Louis was subdivided using census block polygons and polygons identified have combined sewer systems with high aggregate annual discharge. Additionally, indicators representing social, economic, and environmental characteristics, which have demonstrated effects from greenspace, were mapped to identify spatial distribution and overlap. The analysis identified one polygon that could promote multiple desired ecosystem services, while reducing annual discharge into combined sewers, and provide these services to an underserved demographic.

Developing a framework for stormwater management: leveraging ancillary benefits from urban greenspace.

Managing stormwater and wastewater has been a priority for cities for millennia, but has become increasingly complicated as urban areas grow and develop. Since the mid-1800s, cites often relied on an integrated system of underground pipes, pumps, and other built infrastructure (termed gray infrastructure) to convey stormwater away from developed areas. Unfortunately, this gray infrastructure is aging and often exceeds its designed capacity. In an effort to alleviate issues related to excess stormwater, many urban areas across the United States are interested in using green infrastructure as a stopgap or supplement to inadequate gray infrastructure. Green infrastructure and other greenspace promote interception and/or infiltration of stormwater by using the natural hydrologic properties of soil and vegetation. Furthermore, there are numerous ancillary benefits, in addition to stormwater benefits, that make the use of greenspace desirable. Collectively, these ecosystem services can benefit multiple aspects of a community by providing benefits in a targeted manner. In this paper, we present a framework for balancing stormwater management against ancillary benefits of urban greenspace. The framework is structured around the Millennium Ecosystem Assessment ecosystem service categories: provisioning, cultural, regulatory, and supporting services. The purpose is to help communities better manage their systems by 1) allowing stakeholders to prioritize and address their needs and concerns within a community, and 2) maximize the ecosystem service benefits received from urban greenspace.