Scientific research of biodiversity or ecosystems

Rapid urbanization and a population density of 6,247 people per km² have placed significant stress on Nairobi's natural resources (Ref 1). The 40-km long Nairobi River Basin, originating from the Ondiri Swamp, serves as a vital water source for the city (Ref 1, 2). However, it has suffered severe pollution from untreated sewage, solid waste, industrial contaminants, plastics, and agricultural runoff (Ref 1, 3). This degradation has had a serious impact on the ecosystem, local residents, and biodiversity (Ref 3).

To address these issues, the Nairobi River Basin Programme (NRBP), sponsored by UNEP, was launched in 1999 (Ref 4). Since then, government and non-state actors have worked together on solid waste management, riparian restoration, and wastewater control (Ref 1). The program was implemented in two phases: Phase I (2003–2006) and Phase II (2006–2009), involving stakeholders from the government, private sector, and civil society (Ref 1, 4, 5). Despite these efforts, a study from 2017 found significant tree removal along the river, and between 1988 and 2014, encroachment into the 30-meter riparian buffer zone dramatically increased, particularly between 2010 and 2014, further degrading the river’s health (Ref 1).

The Recovery of Cienaga Juan Polo project is primarily aimed at reopening the natural mouth of the Manzanillos to restore water flow between the sea and the Juan Polo coastal wetland, which has been affected by human activities leading to high salinity and water stagnation issues (ref 2). The project is led by Fundacion Serena del Mar. Environmental and social sustainability are core components of the project design, which has included extensive community consultations since 2013. These consultations have resulted in agreements covering employment opportunities, education, and infrastructure development (ref 2). Key implementation activities include the reforestation of mangroves and targeted interventions to address ecological degradation, such as increased salinity, water stagnation, and biodiversity loss (ref 2). The project also seeks to enhance the quality of life for surrounding communities by restoring traditional economic activities, particularly fishing, and integrating sustainable urban planning elements such as canals, sluices, and navigable waterways. These features are designed to support the development of a "blue corridor" for aquatic mobility within Serena del Mar (ref 2, 3). In addition, it also contributes to local capacity building through environmental education programs that engage community members, researchers, and NGOs in biodiversity monitoring and sustainable practices​ (ref 1).

The Çukurova Arboretum is located 17 km from the city centre of Adana, close to the Seyhan Dam lake. Established in 1997, it aims to conserve and protect plant species and vegetation from the region and those adapted to the Mediterranean climate (Ref. 2,5). Given its location outside the city centre and its proximity to freshwater resources, the Arboretum has been praised as a refuge for relaxation and recreation away from the stress of the city (Ref. 1,3). The area has been established by the Regional Forest Directorate of Adana in cooperation with the Istanbul University, department of Forestry (Ref. 2,3). In 2011 and 2013 new infrastructure was added to the arboretum, including a nursery, main road network connection and irrigation (Ref. 2). Visitors and researchers can access over 1050 ha hosting more than 700 plant taxa in different thematic areas, such as mediterranean vegetation, rose gardens, succulent and cactus areas, medicinal and aromatic plant gardens and an aquatic plants exhibition center which is a special feature to the site (Ref. 2). For research specifically, laboratory projects have been established and nurseries continue to ensure the supply of plant material (Ref.1). Over the years, the Arboretum has been equipped with more elaborate infrastructure and exhebition sites as well as educational material available to visitors (Ref.1,2,4).

The Molentargius-Salt Works Regional Natural Park, spanning approximately 1,600 hectares, is located in South Sardinia between the towns of Cagliari and Quartu Sant'Elena, adjacent to the Poetto seafront. The park features diverse ecosystems, including wetlands and salt flats, and houses the Orto Botanico di Cagliari, which showcases native Mediterranean plants.
In 2016, a project was initiated by a group of stakeholders to preserve and enhance biodiversity within the park. The project's goals are to protect and promote the unique ecosystems, such as the fossil beach, and manage invasive species like the Louisiana crayfish. Through various activities—educational programs, public engagement, and conservation efforts—the initiative aims to raise awareness and deepen understanding of local biodiversity and its historical evolution.
A primary focus of the project is the conservation of the Orto Botanico area in Is Arenas, which contains a fossil beach that offers valuable geological insights into the region's past. Planned activities include cleaning and securing the area, creating educational pathways, and employing multimedia tools to engage visitors. The emphasis is on teaching the public, especially students, about biodiversity as a result of environmental adaptation through practical learning and cultural exchanges.
Another critical aspect of the project is the study and control of the invasive Louisiana crayfish, which threatens the park’s biodiversity by contributing to riverbank erosion and impacting native fauna. The project will incorporate scientific research on the crayfish and develop strategies to limit its spread, aiming to protect the park’s delicate ecosystems from further disruption by invasive species.
Lastly, the project emphasizes cultural exchange and social inclusion and fosters dialogue on the shared ecological challenges in Parco Molentargius. (Refs. 1, 2 & 5)

The project aims to protect seagrass meadows, which are vital habitats for the prey of resident dolphins and essential to the local fishing economy. The initiative involves local fisherwomen, called "Keepers of the Sea," in activities such as marine education, awareness campaigns, and monitoring the health of the seagrass meadows (Ref 1). Founded in 2015, Ocean Alive aligns with several UN Sustainable Development Goals, including ocean conservation, gender equality, quality education, and climate action (Ref 4). The project is supported by partnerships with UNESCO and other organizations, and it extends its efforts to Portuguese-speaking African countries. Ocean Alive’s activities also include advocacy for blue carbon ecosystems and programs that involve community engagement and social innovation (Ref 2, Ref 5).
One of several implementation projects targeted safeguarding the young seagrass meadow at Cambalhão Bay, at the entrance of the Sado estuary, as an Ocean Alive’s initiative in partnership with SeaTrees by Sustainable Surf (Ref. 2). The Cambalhão meadow is made up of 202 patches of seagrass. Unregulated shipping is one of the factors in the degradation of the prairie, and to protect it, Ocean Alive is running a campaign to raise awareness about recreational boating (Ref. 6).

Situated in the southern suburbs of Kunming City, Dianchi is one of the largest freshwater lakes in Yunnan and the sixth largest in China (Refs 1, 2). However, due to rapid industrial development, agricultural activities around the lake, land reclamation, and population growth, Dianchi Lake became severely polluted, ranking among the most contaminated lakes in China. This pollution threatened biodiversity and degraded natural habitats (Refs 1, 2, 3). The introduction of exotic species further disrupted the lake’s ecological balance (Ref 1).
In response, the Kunming Institute of Zoology (KIZ), with funding from the Chinese Government, World Bank and the Global Environment Facility (GEF) launched the Lake Dianchi Freshwater Biodiversity Restoration Project. This initiative aimed to restore natural habitats, improve water quality through biological means, and foster community engagement and institutional capacity, creating a sustainable framework for the long-term conservation of Dianchi's unique freshwater biodiversity (Refs 1, 4).
The project was implemented across four key components: Wetland Management and Restoration, Surveys and Monitoring of Species Conservation, Capacity Building and Training, and Public Awareness (ibid.). The project was rated 'Satisfactory' in terms of outcomes, sustainability, and execution under a comprehensive evaluation framework that employed multiple indicators (Refs 4, 5).

In the 1980s, rapid industrialization, urban population growth, and increased water usage led to severe pollution in Dianchi Lake, exceeding its environmental capacity and significantly degrading its water quality (Ref 1). This deterioration had serious effects on nearby ecosystems, including Cuihu Lake (Ref 2). Cuihu Lake (翠湖), also known as Green Lake Park, is a well-known park and body of water in the center of Kunming, Yunnan Province, China. In Cuihu lake the decline in water quality caused a sharp reduction in native species like the golden line barb, which depend on the local ecosystem for survival, pushing them to near extinction and destabilizing the entire ecosystem (ibid.).
To address this, several effective initiatives have been launched to restore Cuihu Lake’s ecosystem in recent years (Ref 2, 3). One of them was started in 2020 when a restoration project was initiated by the site's administration in collaboration with Dr. Li Weiwei’s team from the Kunming Institute of Zoology, Chinese Academy of Sciences. The project focused on creating micro-habitats and restoring the aquatic ecosystem (ibid.). Ecosystem and biodiversity restoration efforts were conducted across a 5,000 m² area on the east side of Green Lake Park, covering approximately 1/27th of the lake (ibid.).
As a result, more than 20 aquatic animal species are now thriving and contributing to water purification, while three submerged plant species cover over 50% of the project area (Ref 2, 3, 4). Bird diversity and numbers are also increasing, with species like white-breasted kingfishers, green-winged teals, and crested guinea-fowls returning to the area (ibid.). Additionally, there has been a significant improvement in water quality (ibid.).

The Çukurova University Botanical Garden was initiated in 1972 by the Department for Landscape Architecture to protect and conserve the rich native and non-native biodiversity of the region for future generations (Ref. 5,9). Its establishment responds to the lack of Botanical Gardens in Türkiye despite the country's great diversity. The Garden also wants to offer protection for increasingly threatened species in the face of rapid and uncontrolled urbanization (Ref. 5,9). Being located close to two Deltas and an important agricultural region, the collection also aims to include a great number of wetland and agricultural species, drawing public attention to the importance of these ecosystems (Ref. 6). As such, the University invites every school in Adana to visit and participate in its ongoing educational activities and primary school children are offered hands-on gardening programmes (Ref. 1,2). Furthermore, visitors can immerse themselves and learn about various vegetation zones, including endemic maquis, where stairs, walking paths and information boards have been installed (Ref. 4). The University maintains research activities in the Botanical Garden and in on site laboratories, which regularly host interns (Ref. 4). To ensure the stready supply of plant material for landscaping and education, nurseries have been set up and in 2020 a 250 m² medicinal and aromatic plant greenhouse was added where students of the Faculty of Agriculture are trained and endemic species grown (Ref. 9,10).

The first medicinal plant library in Martinique was created by the Ypiranga Martinique association, which inaugurated the project in 2019. The initiative was developed to preserve and revitalize traditional knowledge of medicinal plants in Martinique, integrating agroecology , modern scientific understanding, and ancestral practices.
The project is located on land provided by the municipality in the Tivoli neighborhood, and it serves as an educational resource, a functional pharmacy, and includes a small shared vegetables garden. Visitors, local residents, and researchers can access information on over 150 native Caribbean plants and their medicinal properties. The site includes two educational trails: one following the river that crosses the garden and a sensory trail designed to help visitors "reconnect with nature." Each plant is identified with information boards detailing its medicinal uses, including whether these uses are scientifically validated.
The project also aims to address social exclusion by offering reintegration workshops to troubled teenagers and the unemployed.
The project was financed through a combination of sources: an EU-funded call for projects, a crowdfunding campaign, and regional and national public subsidies.
As a result of its success, in 2021 the initiative was formally replicated with the support of the Caribbean Interreg "OSAIN" project, which led to the creation of 14 additional plant libraries in schools and public spaces. Volunteers and community-based efforts continue to sustain the project, and it has become a model for similar initiatives. (Ref. 1,2,4,5,6,7)

Liquid 3 is the first urban photo-bioreactor in Serbia, developed by an interdisciplinary team at the Institute for Multidisciplinary Research at the University of Belgrade (Ref. 1,2,3). Prompted by an appeal of the United Nations Development Programme (UNDP), the team was eager to find novel approaches to combat the city's severe air pollution issues while being space efficient and providing year-round benefits (Ref. 3). The key to the bioreactor are algae which are very efficient in sequestering carbon and filtering heavy metals from the air (Ref. 2). A Liquid 3 feature can be quickly set and occupies a plot of only 3 m². Some of its benefits include its ability to withstand high levels of air pollution and its ease of installation on surfaces like walkways and other sealed infrastructure (Ref. 2,3). Additionally, by design, Liquid 3 integrates amenities such as power outlets, a bench, and nighttime lighting (Ref. 1). The selected strain of algae can tolerate temperatures between 5-35°C making it deployable all year. However, monthly maintenance is required, during which the water and algae are replaced—both of which can be repurposed, for example, as fertilizers (Ref. 6).The project has received global media coverage as well as a prize for the best innovative and climate-smart solution in Serbia. Its success has prompted the installation of two more such bioreactors in Serbia, with interest coming from other countries such as Hungary and the UAE (Ref. 1,4).