As another indicator of the design’s environmental achievements, biodiversity is now a standard feature in project descriptions. It is important to understand what biodiversity means in urban environments and how architecture and urban design can contribute to it. This is a result of the increasing emphasis on sustainability as a standard, inspired by the UN Sustainable Development Goals. Cities are becoming an important factor in maintaining biodiversity with increasing extinction rates and urbanization gaining ground over natural land. The following explores how cities can foster multi-species habitats.
Biodiversity is the diversity of species and the genetic variation within them. It also includes habitats. More than half of the world’s inhabitants live in urban areas, with urbanization projected to increase to 68% by 2050. This means that significant amounts of natural land and habitats have been lost. Urban areas are expanding rapidly in many natural environments, including Brazil West Africa, Southeast Asia, and Brazil West Africa. Climate actions are also being undermined by the loss of biodiversity, ecosystem integrity, and other factors. Recent studies have shown that cities are more crucial to biodiversity conservation than previously believed. In many cases, cities support a wide range of animals and plants, some of which are more productive in urban areas than those in rural settings.
In this city-biodiversity equation, it is important to include ecosystem services. This refers to the many benefits that humans receive from the natural environment. It includes aspects such as clean air, pollination and extreme weather regulation. Everyday life is dependent on ecosystem services which in turn are supported by biodiversity. This makes it clear how urban environments impact human health. Urban planners, architects, and decision-makers are increasingly aware of the impact that nature has on urban well-being. This is an integral aspect to creating a healthy and sustainable urban environment.
While many cities have taken the lead in dealing with biodiversity loss, Singapore is the most prominent. It has developed a comprehensive strategy to become a “City in Nature” and has since been able to address this issue. This framework calls for Singapore to add 300 hectares more parks and gardens by 2026, establish species recovery plans for 100 plants and 60 animals, and place every household within a 10 minute walk of a park. The city created the Singapore Index for Cities’ Biodiversity in 2008 to help cities assess their biodiversity conservation efforts and provide metrics to guide them in implementing actions plans. In the September 2021 report, experts and cities based on the Singapore Index framework offer suggestions for habitat restoration, urban agriculture, or nature-based infrastructure solutions. The World Economic Forum has launched the BiodiverCities initiative by 2030. This initiative brings together experts and practitioners from both the private and public sectors with climate change and biodiversity conservation expertise to create a model of urban development for nature-positive cities.
The UK Government announced in 2019 that any new development must demonstrate a 10% increase of biodiversity to be approved for planning approval. The “net-gain” condition, which is determined using a biodiversity metric, will be required by 2023. There is less knowledge about architecture and biodiversity than there is about embedded carbon emissions. Architecture has a limited chance to have a significant impact on biodiversity if it is not coordinated at the urban level. There are many ways to include provisions for biodiversity into architectural projects.
Architecture can help to foster biodiversity by creating habitat opportunities, protecting existing habitats, and linking them with other areas. It is important to manage water, use grey-water, and construct materials from recycled material. Green facades, roadsides trees and plant roofs can all help to foster biodiversity. They provide habitat for pollinators, birds and animals, as well as shelter and food. Although construction can be disruptive to local fauna and floras, controlled development and approaches such as Design for Manufacture and Assembly, where components are manufactured off-site, may help reduce the impact. Brownfield sites are home to rich ecosystems, so biodiversity conservation is more important.
Although the importance of urban areas in biodiversity conservation is still being determined, there is growing recognition that cities play a crucial role in solving the global biodiversity crisis. Reversing biodiversity loss requires many actors to work together, including scientists, urban planners, and authorities.