Going for a walk in a natural environment can have a significant effect on well-being, according to researchers from the University of Sheffield.
The research revealed that the greater the biodiversity, the greater the psychological benefit.
Researchers from the De Montfort University in Leicester, led by Dr Richard Fuller, found that green space users were able to accurately assess the number of different species in their vicinity.
This could have an impact on the management of urban green spaces, towards the promotion of a wide variety of plant species.
Dr Fuller said: "Our research shows that maintaining biodiversity levels is important in our increasingly urbanised world, not only for conservation, but also to enhance the quality of life for city residents.
"The quality of green spaces, therefore, needs to be considered to ensure that it serves the multiple purposes of enhancing biodiversity, providing ecosystem services, creating opportunities for contact with nature and enhancing psychological well-being."