Humans rely on a wide range of animals, plants and microorganisms for healthy living environments. It’s well documented that the continuing decline in biodiversity – the variety of life on Earth – is a threat to humanity’s existence, but Andrea Mechelli, a Professor of Early Intervention in Mental Health at London’s Kings College proved via his research that biodiversity can also play a critical role for people’s mental wellbeing.
Previous studies demonstrated that contact with nature benefits mental wellbeing, especially for those who live in cities. For example, the risk of developing the two most prevalent mental disorders in the world – depression and anxiety – is 71% lower in urban dwellers who live near green spaces. Most of these studies, however, haven’t considered the extent to which these benefits depend on natural diversity.
Mechelli examined whether environments with a wealth of natural features, such as trees, plants, waterways and wildlife, would bring greater mental health benefits than those with a smaller range of natural features. They found that green spaces with high natural diversity have more mental health benefits than those with low natural diversity.
Wilding and wellbeing
The results of the study suggest that the benefits of nature for mental wellbeing can maximised by protecting and promoting biodiversity in our natural environments. This means moving away from heavily curated pockets of greenery – such as landscaped gardens and parks of mown grass, which are typically associated with low biodiversity – towards spaces such as wild meadows and waterways which provide a more attractive habitat for a range of plants and animals.
Mechelli’s findings are consistent with other studies on the beneficial impacts of diverse natural habitats for mental health. For example: a recent survey of 15,000 households found that those who lived near natural areas rich in plant and bird species report lower rates of mental health issues – even after accounting for social and economic differences between participants.
Mechelli’s study expands this evidence by showing that, to experience the mental health benefits of biodiversity, we do not have to live near a diverse green space over a long period of time. In fact, benefits can be experienced through daily brief incidental encounters with biodiverse nature.
Stimulation for the senses
There are many ways that nature, particularly biodiversity, can benefit mental health. Biodiverse nature offers more stimulation for the senses, which may improve concentration, reduce mental fatigue and restore cognitive resources – such as memory and attention span. Also, people living in or near a natural space tend to spend more time exercising or socialising outdoors, both of which promote the release of endorphins and other mood-boosting hormones.
Diverse natural environments also play essential roles in reducing pollutants and moderating temperatures. This helps protect against chronic physical conditions such as allergies and asthma, while decreasing stress levels and enhancing mental wellbeing.
This article originally appeared in The Conversation and is republished with permission.
