Treetroit
Over the past century, vast portions of the world’s oldest forests have been lost to clear-cutting and managed forestry (1). Arboretum Detroit is working to counter this trend by reforesting Detroit’s urban landscape, transforming abandoned city blocks into thriving groves of trees (1). Each parcel of land features trees that showcase the unique contours and characteristics of specific species, creating a diverse urban forest mosaic across the city (1). These "forest patches" are protected, designed to mature safely for generations, offering a space of tranquility and natural beauty for all Detroiters (1).
Arboretum Detroit’s main goal is to cultivate environmental consciousness, inspiring the community to consider our interconnectedness with nature and our impact on it (1). Through their reforestation mission, they demonstrate the ecological, cultural, aesthetic, and economic value of trees, both locally and globally (1). Trees alter our environment by using their leaves to filter the air we breathe by removing dust and other particles. Deciduous shade trees cool homes in the summer and allow the winter sun to heat homes when they lose their leaves. Trees can serve as a windbreak. The more compact the foliage on the group of trees the more effective the windbreak. Their pilot project, launched on Earth Day 2019, brought these values to life. Volunteers and members planted 21 trees across the site, including species like Princeton Sentry Ginkgo, Redpoint Red Maple, Paper Birch, Cedar, Yew, and understory trees like Kousa Dogwood and Forest Pansy Redbud, enhancing the habitat for local pollinators and birds (2). The trees were arranged in trios, interspersed with native seeds, soil, compost, and glacial boulders to create a healthy and engaging environment for all (2).
Arboretum Detroit’s main goal is to cultivate environmental consciousness, inspiring the community to consider our interconnectedness with nature and our impact on it (1). Through their reforestation mission, they demonstrate the ecological, cultural, aesthetic, and economic value of trees, both locally and globally (1). Trees alter our environment by using their leaves to filter the air we breathe by removing dust and other particles. Deciduous shade trees cool homes in the summer and allow the winter sun to heat homes when they lose their leaves. Trees can serve as a windbreak. The more compact the foliage on the group of trees the more effective the windbreak. Their pilot project, launched on Earth Day 2019, brought these values to life. Volunteers and members planted 21 trees across the site, including species like Princeton Sentry Ginkgo, Redpoint Red Maple, Paper Birch, Cedar, Yew, and understory trees like Kousa Dogwood and Forest Pansy Redbud, enhancing the habitat for local pollinators and birds (2). The trees were arranged in trios, interspersed with native seeds, soil, compost, and glacial boulders to create a healthy and engaging environment for all (2).
HortaFCUL: University Community Garden
HortaFCUL is a project created and managed by the Faculty of Sciences at the University of Lisbon to raise awareness and promote the practice of permaculture as a solution to the ecological, social, and economic problems the world is facing (1). This initiative began in 2009 on the University campus through a garden, which allowed HortaFCUL to start conducting some activities that could answer some socio-environmental challenges, such as food security and sovereignty, ecosystem degradation and climate change (13), by raising awareness, teaching, and practising many aspects involved in permaculture and urban agriculture (2). Its focus has been on regenerating soil in an urban environment and creating productive landscapes for people and other beings (12). They grow different types of plants (vegetables, shrubs, trees) in different ways (swales, raised beds, greenhouses) to increase plant diversity and foster ecosystems (13).
The project is managed by students and researchers, who hold educational activities, such as courses, workshops, and dissemination activities (events, discussions, fairs, and conferences) (2). The project is organised according to a non-hierarchical sociocratic model, in which all decisions are made as a group, and where all ideas, critiques, and suggestions are seen as added value and an opportunity to improve techniques and knowledge (3). Additionally, it is open to the community, allowing anyone interested to participate and volunteer (1).
HortaFCUL is also one of the pioneering permaculture projects in operation in the Lisbon region and is now recognized as a national reference centre for permaculture (2). Since its inception, HortaFCUL has sought to be a hub that attracts people, organizations, and other initiatives, and it is currently a point of contact between different projects and associations, such as local businesses, educational institutions, and networks (5).
The project is managed by students and researchers, who hold educational activities, such as courses, workshops, and dissemination activities (events, discussions, fairs, and conferences) (2). The project is organised according to a non-hierarchical sociocratic model, in which all decisions are made as a group, and where all ideas, critiques, and suggestions are seen as added value and an opportunity to improve techniques and knowledge (3). Additionally, it is open to the community, allowing anyone interested to participate and volunteer (1).
HortaFCUL is also one of the pioneering permaculture projects in operation in the Lisbon region and is now recognized as a national reference centre for permaculture (2). Since its inception, HortaFCUL has sought to be a hub that attracts people, organizations, and other initiatives, and it is currently a point of contact between different projects and associations, such as local businesses, educational institutions, and networks (5).
Greening Colombo
The financial capital of Sri Lanka, Colombo, is the fastest-growing city in Sri Lanka, and as such, it is constantly changing. Most expansions in urban areas are taking place without proper planning, which can cause damage to existing pockets of forests, landscapes and green areas in and around the city (1). The environmental impacts of this rapid urbanisation include increased pollution, increased heat due to the expansion of roads/pavements, tall structures that block out light and wind and reduced biodiversity in fauna and flora (1).
To face these challenges, the Federation of Environmental Organisations (FEO) proposed a city-wide Tree Planting Campaign to create an Urban Forest Strategy in public and private lands in the greater Colombo area (1). The plan is to kick-start the program at the Borella Cemetery as it has a large land area available for planting, specifically 178062 sq meters (3). The project started to be implemented in July 2020 with the seasonal rains (1). This project aims to grow urban trees to help mitigate some of the negative impacts of unplanned and rapid urbanisation, thus making the city more resilient to these changes (1).
The trees that will be planted will be mostly native species and also exotic plants will be selected based on specific requirements (1, 3). It is also planned to have flowering plants and shrubs to encourage butterflies, bees and birds to interspace the trees (1). The new parking space near the Borella Cemetery will also be planted with deep root shading trees interspaced with flowering plants (1).
The project aimed to include a large number of stakeholders including the government, the private sector and the residents of Colombo (1). And they have also reached schools in Colombo and hope to involve environmental associations to further the cause (3).
To face these challenges, the Federation of Environmental Organisations (FEO) proposed a city-wide Tree Planting Campaign to create an Urban Forest Strategy in public and private lands in the greater Colombo area (1). The plan is to kick-start the program at the Borella Cemetery as it has a large land area available for planting, specifically 178062 sq meters (3). The project started to be implemented in July 2020 with the seasonal rains (1). This project aims to grow urban trees to help mitigate some of the negative impacts of unplanned and rapid urbanisation, thus making the city more resilient to these changes (1).
The trees that will be planted will be mostly native species and also exotic plants will be selected based on specific requirements (1, 3). It is also planned to have flowering plants and shrubs to encourage butterflies, bees and birds to interspace the trees (1). The new parking space near the Borella Cemetery will also be planted with deep root shading trees interspaced with flowering plants (1).
The project aimed to include a large number of stakeholders including the government, the private sector and the residents of Colombo (1). And they have also reached schools in Colombo and hope to involve environmental associations to further the cause (3).
Renatura pilot: Fast Forests for Lisbon
The Mediterranean climate in Lisbon, already characterised by low precipitation, has been further exacerbated by climate change. The city faces challenges related to biodiversity loss, urban loneliness, and climate anxiety (1). To address these issues, Lisbon's urban development plans have prioritised the re-naturalisation of urban spaces and the integration of ecological networks. Urban nature is now a central component of the city's Master Plan (2012) and other strategic agendas (1).
It is being developed by the LISGREEN project, which aims to enhance ecological connectivity and mitigate the effects of urban heat islands in Lisbon. By establishing nature-based solutions, it aims to restore forests within the city (1, 2, 3). This project encompasses different strategies, such as the RENATURA pilot project. It is a collaboration with the NGO URBEM and involves active public participation in tree planting and forest maintenance. This initiative aims to educate the community about nature, promote well-being, and mitigate extreme climate events (1), through the creation of urban forests.
The main strategy is to create fast forests using the Miyawaki method, which involves dense planting of native trees, removal of invasive plants, and intensive initial care. This approach accelerates the growth of natural forests within a short period, using native species and reducing the need for watering (1)
The first fast forest was developed in Parque Casal Vistoso within Bela Vista Park, within the Eastern Green Corridor of Lisbon. The park is being underutilised because of the lack of shade (1). Thus, this initiative encouraged volunteers to participate in tree planting and forest maintenance activities (3). The NbS intervention began with a 300m² experimental plot near the Vale da Montanha pedestrian bridge and has since expanded to a new 1,500m² plot on the opposite side of the bridge (2). Over 500 volunteers joined the effort, planting more than 3,800 trees (1)
It is being developed by the LISGREEN project, which aims to enhance ecological connectivity and mitigate the effects of urban heat islands in Lisbon. By establishing nature-based solutions, it aims to restore forests within the city (1, 2, 3). This project encompasses different strategies, such as the RENATURA pilot project. It is a collaboration with the NGO URBEM and involves active public participation in tree planting and forest maintenance. This initiative aims to educate the community about nature, promote well-being, and mitigate extreme climate events (1), through the creation of urban forests.
The main strategy is to create fast forests using the Miyawaki method, which involves dense planting of native trees, removal of invasive plants, and intensive initial care. This approach accelerates the growth of natural forests within a short period, using native species and reducing the need for watering (1)
The first fast forest was developed in Parque Casal Vistoso within Bela Vista Park, within the Eastern Green Corridor of Lisbon. The park is being underutilised because of the lack of shade (1). Thus, this initiative encouraged volunteers to participate in tree planting and forest maintenance activities (3). The NbS intervention began with a 300m² experimental plot near the Vale da Montanha pedestrian bridge and has since expanded to a new 1,500m² plot on the opposite side of the bridge (2). Over 500 volunteers joined the effort, planting more than 3,800 trees (1)
Life Lungs Project
Lisbon is facing an increasing threat linked to climate change due to its geographical location and climate (6), which has had a negative impact on health and quality of life in the city (5). Its average annual precipitation is decreasing, although the city experiences more winter precipitation. This results in longer droughts and more seasonal flooding, which reduces water retention and soil conservation (6). Average temperatures are increasing by 14°C per year, with maximum temperatures up to 5°C higher (6).
As an adaptation measure to these challenges, the LIFE LUNGS project aims to increase Lisbon's resilience by implementing green infrastructure and promoting related ecosystem services (1, 3, 5, 6). Thus, it focuses on measures aimed at coping with temperature increase, mitigating the effects of heat waves and water scarcity, which are expected to become more frequent, being in line with the climate policies adopted by the municipality. The project runs from 2019/2020 to 2024/2025 (1, 5, 6). It aims to address cross-cutting issues such as climate, water and biodiversity (3). The project expects to work hand in hand with the City of Malaga, which has been developing projects aimed at adapting the city to climate change. It is expected to replicate the work in Malaga and post-project to 2 national territories, and 1 in the EU (4). It is also intended to transfer the project work to be implemented in private areas that are part of Lisbon's green infrastructure, and to disseminate and technically train municipalities of the Lisbon Metropolitan Area and other municipalities committed to climate change adaptation (4).
As an adaptation measure to these challenges, the LIFE LUNGS project aims to increase Lisbon's resilience by implementing green infrastructure and promoting related ecosystem services (1, 3, 5, 6). Thus, it focuses on measures aimed at coping with temperature increase, mitigating the effects of heat waves and water scarcity, which are expected to become more frequent, being in line with the climate policies adopted by the municipality. The project runs from 2019/2020 to 2024/2025 (1, 5, 6). It aims to address cross-cutting issues such as climate, water and biodiversity (3). The project expects to work hand in hand with the City of Malaga, which has been developing projects aimed at adapting the city to climate change. It is expected to replicate the work in Malaga and post-project to 2 national territories, and 1 in the EU (4). It is also intended to transfer the project work to be implemented in private areas that are part of Lisbon's green infrastructure, and to disseminate and technically train municipalities of the Lisbon Metropolitan Area and other municipalities committed to climate change adaptation (4).
Metta Garden
Public spaces in Colombo are disappearing due to rising land prices, causing infrastructure issues that harm citizens' health, especially in low-income areas (3). One proposed solution to address the problems caused by rapid urbanization is the creation of community gardens, which can at least improve low-income residents' diets and immune systems and address malnutrition (3).
Considering the limited urban space for both citizens and other living beings, the organization Eco-friendly Volunteers decided to create a community garden. The Metta Garden in Colombo (1, 2) aims to bring back urban biodiversity through organic home gardening, generating healthy food for people and creating living space for many other animals and plants (2). Following the Buddhist concept of Metta (loving-kindness to all beings), it promotes walking meditation paths and facilities to experience nature using all five sensory organs (1), in addition to being a place for experiencing loving-kindness for both human and non-human living beings, seen and unseen (4, 5).
It has become a training institute for many stakeholders seeking to grow organic food and earn a better income through the high demand for organic products (2). At the same time, it serves as a biodiversity spot, attracting butterflies, bees, and other forms of wildlife to an urban environment (2).
The area is located in the middle of a semi-urbanized area, on the outskirts of Boralesgamuwa (2, 3). Maintained by a group of volunteers, it features a greenhouse and a plot of land of around 5,000 sq feet, populated with vegetable patches, a butterfly garden, flowers and rare medicinal plants (3, 4). The garden was divided into four sections representing the Buddhist elements: water, heat, air, and solid. Each section features specific plants and designs, like a pond for water, a compost pit for heat, tall plants for air, and a rock garden for solid. The layout follows a mandala design based on permaculture principles (4).
Considering the limited urban space for both citizens and other living beings, the organization Eco-friendly Volunteers decided to create a community garden. The Metta Garden in Colombo (1, 2) aims to bring back urban biodiversity through organic home gardening, generating healthy food for people and creating living space for many other animals and plants (2). Following the Buddhist concept of Metta (loving-kindness to all beings), it promotes walking meditation paths and facilities to experience nature using all five sensory organs (1), in addition to being a place for experiencing loving-kindness for both human and non-human living beings, seen and unseen (4, 5).
It has become a training institute for many stakeholders seeking to grow organic food and earn a better income through the high demand for organic products (2). At the same time, it serves as a biodiversity spot, attracting butterflies, bees, and other forms of wildlife to an urban environment (2).
The area is located in the middle of a semi-urbanized area, on the outskirts of Boralesgamuwa (2, 3). Maintained by a group of volunteers, it features a greenhouse and a plot of land of around 5,000 sq feet, populated with vegetable patches, a butterfly garden, flowers and rare medicinal plants (3, 4). The garden was divided into four sections representing the Buddhist elements: water, heat, air, and solid. Each section features specific plants and designs, like a pond for water, a compost pit for heat, tall plants for air, and a rock garden for solid. The layout follows a mandala design based on permaculture principles (4).
Gothatuwa Wetland Park
Sri Lanka, particularly its low-lying coastal areas, faces recurring flooding challenges exacerbated by climate change, coastal erosion, and urbanization (1). Wetlands have emerged as crucial ecosystems in mitigating these risks, acting as natural sponges during heavy rainfall and releasing water gradually as flood levels subside (1). Beyond flood control, wetlands play a vital role in environmental quality. Their biodiversity helps filter pollutants and chemicals from the air and water, creating a healthier environment for both humans and wildlife (1). In 2018, Colombo was designated as a Global Wetland City under the Ramsar Convention, becoming the first and only capital city to receive this recognition (1). Recognizing the significance of wetlands as nature-based solutions, international institutions have prioritized their conservation through financing programs (1), and the city has developed projects to raise awareness and involve its citizens in their protection (1). These efforts have resulted in the creation of four wetland parks in the city, that comparing to a wetland, the wetland parks have more human intervention. Thus, they are focused on different topics and activities (2): Diyasaru Park, Beddagana Wetland Park (managed by the Urban Development Authority), Kotte Rampart Wetland Park (managed by the Urban Development Authority), and the Gothatuwa Wetland Park (managed by the Sri Lanka Land Development Corporation) (2). Gothatuwa Park is the newest wetland park and it is located in the flood-prone Gothatuwa neighbourhood (1). Inaugurated in 2024, It has a recreational focus, with trails for cyclists and hikers, and together with the other wetland complex, this park is designed to make the wetlands a cornerstone of local people's lives (1). Currently, environmental education activities are carried out in the park, focusing on managing aquatic invasive plants, tree planting and solid waste collection (3).
Thalangama Wetlands
The Thalangama wetlands are part of a network of wetland ecosystems around Colombo city that spread over 20 km2 and provide critical life support to the city. These ecosystems keep people safe from floods, cool the air, filter polluted water, provide food and medicines, and fight climate change (10). These wetlands have become an environmental protection area and a biodiversity hotspot in a rapidly urbanising environment, as they host an array of plants and animals, including the endangered fishing cat and otter (5, 10). In 2007, Thalangama Lake and its surroundings were declared an Environmental Protection Area (EPA) under the National Environmental Act (4, 5). This protected area covers approximately 118 hectares (4) and includes two man-made reservoirs: Thalangama Tank (11 ha) and Averihena Tank (3.2 ha), located just 300 meters apart (5). The area hosts floating and rooted plants, scrublands, and trees that provide habitat to up to 100 species of migratory, resident, and endemic birds throughout the year. In addition, the area supports 30 species of dragonflies, 12 species of reptiles, 10 species of mammals, and 15 species of freshwater fish (1, 4). Since the lakes and their surroundings were declared an EPA, only limited uses are permitted, such as traditional fishing and rice cultivation (4, 5). The lakes are also important for floodwater retention and have high scenic and aesthetic value, attracting many visitors, and scientific and educational activities (5, 13).
However, due to the area's rapid urbanisation, land values have increased significantly, leading to excessive landfilling and the reclamation of paddy lands for housing. This is compounded by the indiscriminate disposal of garbage and construction waste and the spread of invasive species (5). These challenges have also led to the engagement of surrounding communities in managing and maintaining it (11).
However, due to the area's rapid urbanisation, land values have increased significantly, leading to excessive landfilling and the reclamation of paddy lands for housing. This is compounded by the indiscriminate disposal of garbage and construction waste and the spread of invasive species (5). These challenges have also led to the engagement of surrounding communities in managing and maintaining it (11).
Sacred Grounds St Suzanne Rain Gardens
In 2018, the City of Detroit implemented a drainage charge to help cover the costs of capturing, conveying, pumping, treating, and safely returning combined sewage to the Detroit and Rouge Rivers (1). The charge is calculated based on each parcel’s impact on the sewer system, particularly by measuring impervious acreage (1). Since then, this fee has posed significant challenges for one group in particular: Detroit’s houses of worship (2). Churches, with their large roofs and parking lots, face higher monthly drainage charges, creating financial strain for many faith leaders (2).
To support these institutions, Sacred Grounds has been providing grants, labor, and design assistance to install projects that reduce water bills and drainage fees (2). Sacred Grounds collaborates with the National Wildlife Federation, Friends of the Rouge, and Sierra Club of Michigan to implement these projects through the city’s green credit program (2). A recent initiative involved installing four rain gardens located on the perimeter of St. Suzanne Our Lady Gate of Heaven Church (3). These bioretention gardens, funded by several private and public actors and led by Detroit Future City, diverts water from 20 large downspouts, redirecting an estimated 500,000 gallons of runoff annually away from the municipal sewer system (3, 4).
In addition to managing water, the gardens foster a thriving habitat for pollinators and adds beauty to the area (3). St. Suzanne’s commitment to environmental education includes engaging over 130 youth and adults in training programs that build pathways to STEAM careers and opportunities where local residents are often underrepresented (4). The church also features an innovative, eco-friendly outdoor classroom developed by students, further supporting their sustainability mission (4).
To support these institutions, Sacred Grounds has been providing grants, labor, and design assistance to install projects that reduce water bills and drainage fees (2). Sacred Grounds collaborates with the National Wildlife Federation, Friends of the Rouge, and Sierra Club of Michigan to implement these projects through the city’s green credit program (2). A recent initiative involved installing four rain gardens located on the perimeter of St. Suzanne Our Lady Gate of Heaven Church (3). These bioretention gardens, funded by several private and public actors and led by Detroit Future City, diverts water from 20 large downspouts, redirecting an estimated 500,000 gallons of runoff annually away from the municipal sewer system (3, 4).
In addition to managing water, the gardens foster a thriving habitat for pollinators and adds beauty to the area (3). St. Suzanne’s commitment to environmental education includes engaging over 130 youth and adults in training programs that build pathways to STEAM careers and opportunities where local residents are often underrepresented (4). The church also features an innovative, eco-friendly outdoor classroom developed by students, further supporting their sustainability mission (4).
Rescue MI Nature Now Pollinator Project
Across Detroit, neglected properties and vacant lots are a common sight (1). Nearly three-quarters of Detroit residents report that there is currently deterioration—defined in the survey as a building or property visibly declining due to long-term neglect—in their neighborhoods (1). One organization, Rescue MI Nature Now, a Michigan nonprofit, is dedicated to transforming these neglected areas into beautiful, functional spaces that benefit both people and wildlife (2).
In 2022, the organization purchased property from the Detroit Land Bank that was marked for demolition (3). Following extensive renovations, the building—now named the Innovative Youth Studio—has become a hub for multiple community initiatives. These include a community garden across the street, a culinary studio that teaches young people how to prepare nutritious meals, a pollinator studio that educates on the critical role pollinators play in the food chain, and a hydroponic studio where plants are grown using nutrient-rich water instead of soil (3).
The pollinator project, developed in partnership with the U.S. Fish & Wildlife Service, supports small bee colonies by planting areas with trees, flowers, and native plants (2). To further enhance biodiversity and support butterflies, bees, and birds, Rescue MI Nature Now partnered with Bowling Green State University to gain insights into pollinator biodiversity and habitat potential (2). Through this initiative, the organization aims to raise awareness about pollinators, highlight their positive impact, offer guidance on creating pollinator-friendly spaces at home and enhance the quality of life for local residents and communities (2).
Additionally, the organization runs a Sustainable Youth Stewardship Program, where young people learn to garden, grow trees, identify various plants and invasive species, and practice conservation skills such as creating pollinator habitats and managing community gardens (3).
In 2022, the organization purchased property from the Detroit Land Bank that was marked for demolition (3). Following extensive renovations, the building—now named the Innovative Youth Studio—has become a hub for multiple community initiatives. These include a community garden across the street, a culinary studio that teaches young people how to prepare nutritious meals, a pollinator studio that educates on the critical role pollinators play in the food chain, and a hydroponic studio where plants are grown using nutrient-rich water instead of soil (3).
The pollinator project, developed in partnership with the U.S. Fish & Wildlife Service, supports small bee colonies by planting areas with trees, flowers, and native plants (2). To further enhance biodiversity and support butterflies, bees, and birds, Rescue MI Nature Now partnered with Bowling Green State University to gain insights into pollinator biodiversity and habitat potential (2). Through this initiative, the organization aims to raise awareness about pollinators, highlight their positive impact, offer guidance on creating pollinator-friendly spaces at home and enhance the quality of life for local residents and communities (2).
Additionally, the organization runs a Sustainable Youth Stewardship Program, where young people learn to garden, grow trees, identify various plants and invasive species, and practice conservation skills such as creating pollinator habitats and managing community gardens (3).

