The green infrastructure is defined as a tool for ecological, economic and social benefits through nature-based solutions, helping to understand the benefits of nature, and to mobilize investments that sustain and improve these benefits, according to the European Commission’s Green Infrastructure Declaration. In other words, the connection and network between all high-quality natural, semi-natural and other urban green areas that provide ecosystem services can be regarded as green infrastructure .
The green infrastructure covers planning, design and management of urban regeneration, controlling urban growth, protecting environmental resources, economic development, and urban renewal applications which develops the ability to provide and manage biodiversity in both rural and urban environments within a broad ecosystem, and to offer ecosystem products and services such as nature’s clean air and water. Green Infrastructure combines the physical structures on green areas or blue areas when considering aquatic ecosystems, seas and lands including coastal areas.
Green infrastructure activities are also valuable in terms of minimizing the adverse effects of climate change on ecosystem products and services, as well as increasing the capacity and efficiency of these products and services. Although, it is still unclear how many ecosystem services are available on this planet, the “Millennium Ecosystem Assessment Report”, one of the most important publications on this subject, divides ecosystem services into 4 main group: provisioning services, regulating services, cultural services and supporting services. Food and water supply directly from nature, regulation of water cleaning and pollination, ecotourism and recreation areas, food cycle and water cycle support are can be given as examples for these services relatively .
In addition to the positive impacts on ecosystem services, green infrastructure studies have become an important defense mechanism against the adverse effects of climate change in urban areas and in communities through “nature-based solutions”. Within the scope of nature-based solutions, many different application possibilities are exist under the headings such as water interventions, re-naturing urbanization and non-technical interventions. Green infrastructure studies are one of the basic elements of nature based solutions besides these headings. Some of the examples of combining green infrastructure applications to fight against the adverse effects of climate change and nature-based solutions can be seen below:
• Reflective / porous surface coatings
• Resin-bonded floor
• Solar energy road
• Pollinator units – house, fence, wall, roof
• Green retaining wall
• Green cycle way
• Wildlife bridge
• Wooden corridor serving as a carbon sink
• Green routes and sightseeing routes
• Green noise barriers
• Sustainable urban drainage
• Rain gardens
• Live breakwater
• Artificial reef
• Rainwater watershed
• Flood / rainwater cycle
• Constructed wetlands
• Fruit wall
• Edible garden
• Community hobby gardens
• Green arcade and covering
• Smart soil
• Green vertical walls and facades
• Green roof
• Urban green buildings
• Green / Eco dashboard
• Green infrastructure jobs acquisition / creation
• Green infrastructure modeling programs and applications
As a general conclusion through these examples; It can be seen that green infrastructure solutions are economic, ecologic and sustainable solutions to take precautions and fight against reasons and effects of climate change, such as extreme weather events, degradation and decline of water resources, increase in air pollution, threat to public health, coastal pollution, heat island effect, biodiversity loss and reduction in agricultural production. It is necessary to increase the awareness of the public and administrative units in this area to taking into consideration and to put a priority on green infrastructures during the preparation of investment plans and urban planning studies.