Defining which components belong to green infrastructure is important for its identification, promotion and uptake. The European Commission proposes the following components, which are summarised in a landscape setting in the following table.

Components of green infrastructure

Hubs

Core areas of high biodiversity value, such as protected areas (like Natura 2000 sites) and non-protected core areas with large, healthy and functioning ecosystems

Corridors and stepping stones

Natural features like small watercourses, ponds, hedgerows and woodland stripes

Restored habitats

Reconnect or enhance existing natural areas (e.g. restored reedbad or wildflower meadows)

Buffer zones

Improve the general ecological quality and permeability of the landscape to biodiversity (e.g. wildlife-friendly farming)

Multifunctional zones

With compatible land uses that support multiple land uses in the same spatial area (e.g. food production and recreation)

Source: EC 2013 (full reference at: https://link.springer.com/content/pdf/10.1007%2F978-3-319-56091-5.pdf, p. 36)

In addition to these elements, green infrastructure located in urban urban contexts plays a critical and increasingly important role in biodiversity conservation efforts. This type of GI is described in more detail below. 

Urban green infrastructure

Urban green infrastructure is characterised by different features than its rural counterparts. While the following list of elements is not exhaustive, it aims to provide an overview of some of the most common elements within a specifically urban and peri-urban setting and illustrative examples.

Category

Urban green infrastructure element

Illustrative example

Building greens

Balcony green, ground based green wall, facade-bound green wall, extensive green roof, intensive green roof, atrium, green pavements and green parking pavements, green fences and noise barriers

Green roofs and facades provide habitats and food to insects and small animals (including pollinators), improve building energy efficiency and indoor/outdoor climates, and are particularly useful in dense urban areas with limited open space.

Urban green areas connected to grey infrastructure

Tree alley and street tree/hedge, street green and green verge, house garden, railroad bank, green playground/school ground, green parking lots, riverbank greens

Beyond serving as habitats and ecological stepping stones, street trees provide shade and green space for relaxation for urban residents, as well as improve air quality and climate, thereby also reducing energy needs for heating and cooling.

Parks and (semi)natural urban green areas, including urban forests

Large urban park, historical park/garden, pocket park/parklet, botanical garden/arboreta, zoological garden, neighbourhood green space, institutional green space, cemetery and churchyard, green sport facility, forest, shrubland, abandoned and derelict area with patches of wilderness

Pocket parks are a new trend in urban areas across the globe. They consist of very small greened spaces, often in reclaimed parking or street spaces, and frequently also include resting or play areas. They utilize small spaces efficiently to bring biodiversity into urban areas and provide high-quality recreation space for residents, improving quality of life.

Allotments and community gardens

Allotment, community garden, horticulture

Community gardens create spaces not only for biodiversity, but also for urban food provision. They encourage residents to get involved in garden management, contributing to social inclusion and cohesion.

Agricultural land

Arable land, grassland, tree meadow/orchard, biofuel production/ agroforestry, horticulture

Agricultural land in urban and peri-urban areas are important for providing habitat to agricultural species in and near cities, and also for provision of urban residents with fresh and healthy food when adequate food market structures are in place

Green areas for water management

Rain gardens or sustainable urban drainage systems (SUDS), rain gardens, swales / filter strips

Systemic approaches to protect urban areas from flood damage and help adapt to changing rainfall patterns by eg combining green, blue and grey components; can include e.g. green roofs, permeable surfaces, infiltration trenches, swales, detention basins.

Blue areas

Lake/pond, river/stream, dry riverbed, canal, estuary, delta, sea coast, wetland/bog/fen/marsh

Sea coasts provide many benefits beyond being habitats for coastal and marine species. For example, they are sources of food and other resources, support tourism, can be part of storm surge and flood management, and provide recreation and exercise space.

Source:  Typology developed by Ecologic Institute based on Cvejić et al. 2015, Xing et al, 2017; Ecologic Institute, 2011, Ndubisi et al., 1995