While urbanisation has led to immense technological advances and thriving cities, biodiversity has heavily declined due to the incessant development of infrastructure from miles of motorways to monstrous skyscrapers.
This article details the sheer importance of biodiversity, the primary negative impacts infrastructure has on it, and covers some of the many specific ways infrastructure harms biodiversity which we should be conscious of, as well as some mitigation strategies to counter the harm, such as Biodiversity Net Gain, the policy since February 2024 that only allows development to be built when they will positively aid biodiversity to a degree of 10%.
The Importance of Considering Biodiversity
Since the Industrial Revolution and its subsequent decades of mass urbanisation and development, our planet’s levels of biodiversity have been in a drastic decline, rendering us now in a global state of biodiversity crisis.
What this means for us is increased risks for human health, with poorer quality air and water, emerging new diseases, plus a reduced availability of the plants we depend on for medicine.
It also means that ecosystems have lost their stability due to increases in invasive species and loss of native species, causing food chain collapses.
This leads to decreased pollination, lack of fertile soil, water purification and other ecosystem services.
Economic structures have taken hits, such as the decline of fisheries and reduced yields of crops.
Biodiversity loss means the loss of forests, oceans and other carbon sequestrators, which exacerbates climate change by increasing greenhouse gas emissions.
It brings threats to food security with decreased livestock production and reduced fish stocks, plus it disrupts water systems causing a decline in freshwater availability.
These reasons, amongst a long, long list of others, highlight the importance of considering biodiversity.
Why Infrastructure Can Cause a Loss of Biodiversity
Infrastructure can cover a vast range of developments, all of which must impact nature to be created and can contribute negatively towards biodiversity in a multitude of ways. The loss of natural habitats, when forests are cleared and wetlands are drained for urban expansion, displaces wildlife and forces animals to migrate. This impacts population densities and can disrupt breeding grounds.
Light pollution increases, air and water quality decreases, such as from increased traffic emissions, building and road runoff, construction site contaminants or streetlights disrupting nocturnal animals.
Infrastructure leads to the altercation of natural landscapes, such as land-levelling for industrial zones or mountain blasting for motorways, causing far-reaching losses of habitats and natural environments for wildlife.
Mechanisms of Biodiversity Loss Due to Infrastructure
Habitat Destruction
Urbanisation leads to habitat description on a mass scale, whether building cities and towns, expanding for agricultural land use, converting wetlands to farmland or wiping out habitats for NSIPs (Nationally Significant Infrastructure Projects).
Some of the most protected wetlands along the coast, at times, are destroyed for resorts or expanding ports. Dam constructions alter river flows and flood ecosystems.
These lead to losses of ecosystem services, with less fertile soils, less water purification and less pollination essential for supporting healthy wildlife.
An imbalanced ecosystem, in turn, is more susceptible to climate change and natural disasters. Habitat destruction, as well, reduces climate regulation with less carbon sequestration from key habitats. This can lead to declines in species richness as well as endemic species.
Fragmentation of Habitats
Infrastructure is an immense contributor towards habitat fragmentation, such as the construction of roads and motorways creating dangerous passages for wildlife between their homes. This increases animal-traffic incidents and reduces genetic diversity by isolating populations, leading to inbreeding and losses of endemic species.
It restricts access to resources, inhibiting species movements, and in turn reduces the wildlife’s adaptability to external harm, like climate change or predation.
Wildlife corridors are areas that allow animals safe passage between fragmented habitats, but there are nowhere near as many of them as there should be.
Pollution
Infrastructure can cause many types of pollution that impact biodiversity in different ways. Water pollution can occur from road maintenance into waterways, construction runoff and industrial charges.
Air pollution happens from vehicle emissions, industrial smoke or dust. Soil contamination can happen from hazardous material leaks or oil spills, and light pollution can come from streetlights or industrial illumination.
Chemical pollution such as pesticides and fertilisers impact biodiversity, and spill from transport accidents or cleaning agents. On a harsher level, radioactive pollution could come from leaks from nuclear plants, radioactive waste from hospitals or industrial contamination.
Introduction of Invasive Species
Infrastructure invites new transportation corridors for invasive species, such as railways, roads and shipping routes with the movement of vehicles like ships and trains facilitating the travel of organisms or seeds.
Hydraulic infrastructure like dams and canals can create passages for invasive species, as well as human-made wildlife corridors such as those built over motorways.
Instead of allowing nature to take its course, a human-made corridor enforces one streamlined passage that endemic, native and invasive species use to travel. Naturally, endemic species likely would have thrived and utilised the entire habitat more, but wildlife corridors distribute fairer and equal travel between species.
Alteration of Water Regimes
Water regimes are altered by infrastructure in many ways, such as dams and reservoirs that entirely disrupt river flows and disturb migratory patterns. Extractions of water reduce stream flows, lower groundwater levels and lead to losses of habitats for aquatic species.
Urban runoff can come from infrastructure development, reducing infiltration, and road construction can alter water quality while increasing erosion.
Furthermore, canals and channels affect local hydrology by diverting water from natural pathways, as well as urban stormwater drainage systems.
Hydroelectric power plants and dams, built into rivers and downstream waterways, can alter natural sediment transport processes, impacting biodiversity by altering habitats and nutrient cycling.
Climate Change
Infrastructure causes climate change in many ways, but some of the most common ways are transport emissions; adding masses of thick carbon dioxide to the atmosphere every second, and deforestation; the total wipe-out of our carbon-sequestering forests to build large-scale housing projects or commercial developments.
Energy production from fossil fields calls for coal-fired power plants or natural gas plants, as well as oil refineries, all contributing heavily towards climate change. Traditional methods of cement production are being dismantled due to releasing strong carbon dioxide emissions during the process.
In urban areas, urban heat islands occur when busy cities have an increased temperature, with less natural cooling from less vegetation and an increased use of indoor air conditioning units, adding to global warming.
Disturbance and Noise
Infrastructure can disturb nature in many ways and noise is a primary example, from noisy construction activities during development to enhanced noise from traffic in loud motorways.
This can enhance stress in wildlife, blocking animal communication—such as submarine systems disrupting local communities of whale communications and causing them distress.
Industrial activities are a large contributor, with continuous noise from factory machinery in different patterns every day. Enhanced urban development, such as in cities, leads to more tourism and a higher concentration of recreational activities, causing further disturbances for wildlife.
Resource extraction activities like mining and drilling can be painfully loud for extended periods but also destroy entire habitats, in some cases.
Furthermore, agricultural machinery, like tractors or large equipment, can have a large impact on wildlife.
Barrier Effects
Barrier effects are barriers created by infrastructure; physical objects preventing the free movement of wildlife, fragmenting their homes and habitats, usually disrupting migratory routes.
A key contributor to this are roads and motorways, which at the same time create loud noise disturbances and heavily pollute the environment with constant emission contribution, while simultaneously posing a threat to animals attempting to cross habitats amongst cars and lorries going 80 miles an hour.
Railways also create barrier effects, as well as power lines, posing collision risks for birds.
Waterways and locks can act as barriers for both aquatic and terrestrial animals, blocking routes for migration, such as the European eel, now critically endangered due to hydroelectric dams, overfishing and other external threats.
Resource Exploitation
The planet is filled with natural resources that fuel many foundational ecosystem structures and allow us to operate, but many types of resource extraction are harmful to the environment by nature, with further adverse effects on biodiversity.
Surface mining, for instance, leads to habitat destruction from drilling and blasting, as well as polluted waterways from the subsequent agricultural runoff.
Timber is a heavily demanded resource, meaning that widespread logging and deforestation occur every day, destroying habitats for forest-dependent species.
Overfishing is a form of resource extraction that causes imbalances within ecosystems, leaving them unstable and less resilient to external harm, such as climate change, pollution or bycatch.
Agriculture to extract crops reduces biodiversity levels by enforcing monocultures and puppeteering nature with human-made machines, chemicals and vehicles to wield the maximum crops possible for monetary benefit. Habitats are not allowed to grow in their natural state while agricultural runoff leaves nearby waterways polluted with pesticides and fertilisers.
Mitigation Strategies
Unfortunately, the long-term impacts of the biodiversity losses listed above, as well as the hundreds of others, will only be dire and drastic.
There are many strategies to mitigate the losses of biodiversity caused by infrastructure. With motorways packed full of traffic a primary example, this is mitigated by wildlife corridors, which appear in natural and human-made forms all across the globe, allowing safe passage for animals over the busy roads.
Another strategy is fish ladders and passes installed at dams and fish elevators installed at high dams, allowing for safe passage, monitoring and observation.
Alongside motorways there can be noise barriers, soundproofing the loud traffic from disturbing animals, or noise-reducing materials used in construction, combined with specific set times for loud construction activities to adhere to a pattern and disturb animals marginally less.
Last but not least, Biodiversity Net Gain (BNG) is a way for sustainable development, which came into action for England in February 2024. Entirely unprecedented, it mandates that development large and small (and in 2025, massive) must contribute a 10% gain to the nation’s levels of biodiversity or they will not obtain planning permission.
There are many types of mitigation measures delivered around the world to let urban development continue while lessening the decline of the planet’s crucial levels of biodiversity. Follow us and stay tuned for upcoming blogs for frequent key environmental information.
More Information
https://www.wsp.com/en-ca/insights/ca-integrating-biodiversity-into-infrastructure-development
https://www.infrastructureinvestor.com/waking-up-to-biodiversity-loss
https://www.weforum.org/agenda/2023/02/biodiversity-nature-loss-cop15