Search

Background: Urgent solutions are needed in cities to mitigate twin crises of global climate change and biodiversity loss. Urban nature-based solutions (actions that protect, sustainably manage, and restore ecosystems while simultaneously providing human wellbeing and biodiversity benefits) are being advocated for as multi-functional tools capable of tackling these societal challenges. Urban forest management is a proposed nature-based solution with potential to address both climate change mitigation and biodiversity loss along with multiple other benefits. However, bodies of evidence measuring multiple outcomes (e.g., biodiversity conservation and nature-based climate solutions) remain siloed which limits conservation and management opportunities. In this article, we present a systematic map of the literature on urban forest management strategies that measure both biodiversity goals (through avian conservation) and climate change mitigation goals (through carbon storage and sequestration). Methods: Following a published protocol, we searched for evidence related to urban forest management strategies for (1) avian conservation and (2) carbon solutions within the global temperate region in academic and grey literature. In addition to Scopus, ProQuest and Web of Science Core Collection, we searched 21 specialist websites. We screened English language documents using predefined inclusion criteria on titles and abstracts, and then full texts. All qualifying literature items were coded, and metadata were extracted. No study validity appraisal was conducted. We identified knowledge clusters and gaps related to forest management strategies for both topics. Review findings: Our searches identified 19,073 articles published, of which 5445 were duplicates. The title and abstract screening removed a further 11,019 articles. After full-text screening (1762 and 1406), a total of 277 avian and 169 forest carbon literature items met the eligibility criteria and were included in the final database. We found a large knowledge base for broad-scale avian metrics: abundance, species richness. We similarly found that both avian and carbon solutions most often used broad-scale forest management components: land use type, composition, and forested area and least often considered fragmentation, connectivity, and diversity metrics (abundance, richness). The most understudied avian metrics were foraging, resources, and survival while the most understudied carbon solutions metrics were soil carbon, dead wood and organic matter and infrastructure. Avian literature most often used an experimental design (56% with comparator, 44% no comparator) while forest carbon solutions literature was dominated by observational studies (86%). In both topics, studies most often occurred over short timelines between 0 and 1 and 2–5 years. The body of evidence for both avian and carbon outcomes present a scale-mismatch between the scale of forest management strategy (e.g., land use type) and scale of application (e.g., patch). For example, the majority of studies considered forest strategies at broad scales, like land use type or composition, yet were conducted at a patch or multi-patch scale. Our systematic map also highlights that multi-city and regional urban scales are underrepresented in both carbon solutions and avian conservation and will require additional research efforts. Finally, we highlight gaps in the inclusion of recommendations in both bodies of literature. Roughly 30% of articles in each topic's database did not include recommendations for practitioners or researchers. Conclusions: Our systematic map provides a database and identifies knowledge gaps and clusters of urban forest management strategies for (1) avian conservation and (2) carbon solutions. Overall, our map will allow researchers to fill existing gaps in literature through new research investigations, meta-analyses or systematic reviews while also pointing policymakers toward strong knowledge bases in addition to understudied or mismatched areas that require more funding. [ABSTRACT FROM AUTHOR]

Background: There is global interest in finding innovative solutions that address current climate and societal challenges in an urban context. Cities are often on the front lines of environmental change, meaning urban greening strategies have high potential to provide benefits across human communities, while protecting global biodiversity. There is growing consensus that nature-based solutions can provide multiple benefits to people and nature while also mitigating the effects of climate change. Urban forest management is well-suited to a nature-based solutions framework due to the wide variety of services trees provide our communities. Effective approaches to urban forest management also have the potential to promote other forms of urban biodiversity, particularly birds and species at risk. However, studies that integrate strategies for both climate and biodiversity conservation are rare. The goal of this systematic map is to gather and describe information on two desired outcomes of urban forest management: (1) conserving avian diversity and species at risk (2) carbon storage and sequestration (i.e., nature-based climate solutions). Methods: We will identify relevant articles from two separate searches for inclusion in our systematic map that address (1) urban forestry and avian and species at risk conservation and, (2) urban forestry and carbon storage and sequestration. We will search two bibliographic databases, consult 20 relevant organizational websites, and solicit grey literature through an open call for evidence. Eligibility screening will be conducted at two stages: (1) title and abstract and (2) full text. Relevant information from included papers will be extracted and entered in a searchable, coded database. Synthesis of evidence will describe the key characteristics of each study (e.g., geographic locations, interventions, outcomes, species studied) and identify knowledge gaps and clusters of evidence. Our systematic map will guide further research on opportunities for multiple benefits using nature-based solutions, particularly as they relate to urban forest management. Furthermore, our evidence base will support both management and funding decisions to ensure the effective use of resources for maximum benefits across people and ecosystems. [ABSTRACT FROM AUTHOR]

The urban forest provides our communities with a host of benefits through the delivery of ecosystem services. To properly quantify and sustain these benefits, we require a strong baseline understanding of forest structure and diversity. To date, fine-scale work considering urban forest diversity and ecosystem services has often been limited to trees on public land, considering only one or two green space types. However, the governance of urban green spaces means tree species composition is influenced by management decisions at various levels, including by institutions, municipalities, and individual landowners responsible for their care. Using a mixed-method approach combining a traditional field-inventory and community science project, we inventoried urban trees in the residential neighbourhood of Notre-Dame-de-Grȃce, Montreal. We assessed how tree diversity, composition and structure varies across multiple green space types in the public and private domain (parks, institutions, street rights of way and private yards) at multiple scales. We assessed how service-based traits – traits capturing aspects of plant form and functions that urban residents find beneficial – differed across green space types, with implications for the distribution of ecosystem services across the urban landscape. Green space types displayed meaningful differences in tree diversity, structure, and service-based traits. For example, the inclusion of private trees contributed an additional 52 species (>30% of total species) not found in the local public tree inventory. Trees on private land also tended to be smaller than those in the public domain. Beyond patterns of tree richness, size, and abundance we also observed differences in the composition of tree species and service-based traits at site-scales, particularly between street rights-of way and private yards. While species composition varied considerably across street blocks, blocks were very similar to one another in terms of mean service-based traits. Contrastingly, while species composition was similar from yard to yard, yards differed significantly in mean service-based trait values. Our work emphasises that public tree inventories are unlikely to be fully representative of urban forest composition, structure, and benefits, with implications for urban forest management at larger spatial scales. • Private land contributed unique species representing over 30% of total tree richness. • Per unit area, tree richness, density, and size were highest in street rights-of-way. • Only analyzing public trees may overestimate the amount of regulating services. • Community science can contribute valuable data supplementing public inventories. • Engaging urban residents is key to promoting urban forest diversity and resilience. [ABSTRACT FROM AUTHOR]