Bioeconomy ▶ The production, utilization, conservation, and regeneration of biological resources, including related knowledge, science, technology, and innovation, to provide sustainable solutions (information, products, processes and services) within and across all economic sectors and enable a transformation to a sustainable economy (IACGB, 2020).

Emerging urban forests ▶ spontaneously developing forests in cities (Kowarik et al., 2019).

Entrepreneurship ▶ the activity or skill in starting new businesses, especially when this involves seeing new opportunities and taking on financial risks in the hope of profit (Cambridge Advanced Learner’s Dictionary, 2022; Oxford Advanced Learners’ Dictionary, 2022).

Environmental “eco” entrepreneurship ▶ “an innovative, market-oriented and personalitydriven form of value creation through sustainable environmental innovations in products and services exceeding the start-up phase of a company.” (Mammadova et al., 2021).

Green Care entrepreneurship ▶ processes and outcomes of innovative value creation that harness health and well-being benefits of nature, and result in transformed human-nature attitudes, interactions and relationships (Mammadova et al., 2021).

Green infrastructure (GI) ▶ a strategically planned network of natural and semi-natural areas with other environmental features designed and managed to deliver a wide range of ecosystem services’ in both rural and urban settings (EEA, 2021).

Gross Primary Production (GPP) ▶ is the amount of Carbon biomass, that primary producers (hence, plants) create per unit of time.

Heat island effect ▶ an urban area or metropolitan area is significantly warmer than its surrounding rural areas due to human activities.

Innovation ▶ The process, the outcome, and the mindset needed to create something novel in response to a problem (Kahn, 2018; Taalbi, 2014).

Internet of Nature (IoN) ▶ An approach where urban ecosystems can be described and represented through digital technologies and applications (Galle et al., 2019)

Leaf Area Index (LAI) ▶ corresponds to non-dimensional ratio of one-sided green leaf area per unit ground surface area (both in square meters).

Living biomass ▶ is made up by aboveground structures (including stems, branches, bark, foliage, flowers, fruits and seeds), and belowground structures (including coarse and fine roots and stumps).

Nature-based enterprises ▶ is the most common organisation type and offers products or services where nature is a core element and engages in economic activity (mainly forestry and tourism). Community-benefit enterprises specifically involve communities in governance and management of forests, to provide direct and indirect benefits for the public and the community. Additional objectives include conservation, poverty alleviation, development, cultural revitalisation and political empowerment. For-profit forest enterprises can contribute to the conservation and sustainable use of forests while improving the livelihoods of local populations. Pro-biodiversity businesses contribute to biodiversity and sustainable use of ecosystems services while being financially profitable. The underlying principle is payments for ecosystem services, where beneficiaries are charged for its use through financial mechanisms, and profit is invested in conservation (Kooijman et al., 2021).

Nature-based learning (NBL) ▶ encompasses the acquisition of knowledge, skills, values, attitudes, and behaviours in realms including, but not limited to, academic achievement, personal development, and environmental stewardship. It includes learning about the natural world, but extends to engagement in any subject, skill or interest while in natural surroundings. It includes informal, non-informal and formal learning (Jordan and Chawla, 2019).

Nature-based organisations ▶ use nature as a core element of their service offering, but do not engage in economic activity (public-private companies, community groups and network organisations in forestry, community gardens and tourism). They play an important role in the financing of, and in providing space and regulatory frameworks for NBS (e.g., city departments), as well as for the financing of nature, mainly for nature conservation, and for the empowerment of local communities (e.g., NGO environmental charities) (Kooijman et al., 2021).

Nature-based products and services ▶ delivered by enterprises or organisations, where nature is not at the core of activities (mainly, engineering and renewable energy companies that use nature as an input) (Kooijman, 2021).

Nature-based solutions (NBS) ▶ are defined as solutions that are inspired and supported by nature, which are cost-effective, simultaneously provide environmental, social and economic benefits and help build resilience; such solutions bring more, and more diverse, nature and natural features and processes into cities, landscapes and seascapes, through locally adapted, resource-efficient and systemic interventions (EC, 2021).

Net Ecosystem Production (NEP) ▶ is the difference between Gross Primary Production and Ecosystem Respiration, including respiration by plants and heterotrophic organisms such as animals and microbes, and accounting also for losses due to disturbances.

Net Primary Production (NPP) ▶ corresponds to the remaining primary production after subtracting Respiration of plants (associated to both growth and maintenance) from Gross Primary Production.

Novel ecosystems ▶ Ecosystems emerging after human-induced changes and composed of unprecedented species assemblages (Hobbs et al., 2006).

Photosynthesis ▶ the metabolic process by which green plants and some other organisms transform light energy into chemical energy.

Smart green infrastructure ▶ green infrastructure that undergoes networked monitoring, management, and augmentation to ensure, for instance, adequate irrigation (Gabrys, 2022).

Smart urban forest management ▶ The design, establishment, monitoring, and management of urban trees and vegetation through the use of digital technologies, for the joint purpose of improving the urban environment and engaging all relevant stakeholders in its governance (Nitoslawski et al., 2019)

Social entrepreneurship ▶ aiming to provide innovative solutions to unsolved social problems, putting social value creation at the heart of their mission in order to improve individuals’ and communities’ lives and increase their well-being).

Soil biomass ▶ includes soil organic carbon.

Urban ecosystem services (UES) ▶ benefits to sustain and improve human livelihood and the quality of life services provided by urban and periurban ecosystems: they include provisioning services, regulating services, habitat or supporting services, and cultural services (Haase et al., 2014).

Urban forests ▶ tree-based urban ecosystems comprising all woodlands, groups of trees, and individual trees located in urban and peri-urban areas; they include, therefore, forests, street trees, trees in parks and gardens, and trees in derelict corners (FAO, 2017).

Urban Forest-Based Solutions (UFBS) ▶ a subset of nature-based solutions that builds on tree-based urban ecosystems to address societal perceptions and demands, simultaneously providing ecosystem services for human well-being and biodiversity benefits. They are socio-ecological interventions that combine human management with nature’s functionality within (peri) urban settings, offering great potential for more sustainable urban development (De Vreese, 2018).

Urban forestry (UF) ▶ integrated, interdisciplinary, participatory and strategic approach to planning and managing tree resources in urban areas for their economic, environmental and sociocultural benefits (FAO, 2017).

Urban forestry Initiative ▶ A given project or enterprise whose aim is to sustainably support, improve and/or promote urban forestry development and implementation.