Ecology in our cities: Why urban biodiversity matters
In the UK, conservation charity Plantlife runs an annual campaign to raise awareness of the detrimental effects of excessive lawnmowing. A perfectly manicured lawn may have once been something to be proud of, but keeping grasses cut down is deleterious to the environment. This year, the ‘No Mow May’ campaign reached even more people than in previous years, and helped to raise the public’s awareness of biodiversity in urban areas.
You might assume a lawn is a single type of plant, but if you let it grow beyond a few centimetres tall you will see that there’s more than just grass there. Many types of plant will flourish without regular mowing; more wildflowers will grow, and the biodiversity of your grassy areas will quickly increase.
Let the grasses grow
The best way to provide an environmentally healthy grassy area in your garden is by cutting grasses every four weeks. This allows shorter plants to continue to grow, and infrequent mowing encourages more flowers to appear. In 2021, people reported that taking a break from mowing in May allowed over 250 plant species to appear, along with higher flower counts, turning lawns into biodiversity hotspots.
Why do we want wildflowers?
It’s well documented that insects all around the world are in decline, with as many as 40% of the world’s species under threat of extinction over the next few decades. Insects provide essential support for the proper functioning of many ecosystems as a food source for other animals, and as pollinators they are essential for our own food supplies and maintaining plant species. By creating small islands of an ideal habitat for insects, including wildflowers rich in pollen, we can support insects within built-up cities and urban areas.
Limiting the effects of climate change and providing more habitats for insects are just part of the science of urban ecology.
Urban areas have an important role to play and supporting biodiversity. Human activity is directly altering our planet, through the release of greenhouse gases and physical removal and alteration of natural ecosystems. As a result, climate change is now impacting human welfare in many areas as our local environments change and we see more extreme events such as flooding and heatwaves. We need to restore nature to help address these issues.
Using living organisms in urban areas to help manage the environment is a well-established practice – for example planting trees helps to reduce the ‘heat island’ effect in cities – and many species of plants can help mitigate air pollution. Limiting the effects of climate change and providing more habitats for insects are just part of the science of urban ecology. Scientists are discovering that improved urban biodiversity can support healthy immune systems, mitigate mental health issues and promote post-surgery healing, improve childhood cognitive development, and increase a sense of local community. In addition, improving the biodiversity of urban areas has a real impact on conservation; cities can become homes to critically threatened species. By simply taking the time to change some of our established environmental traditions in our urban areas, we can each have an important positive impact on the world around us.