This letter appeared first in the Friends newsletter for Spring 2013. Receiving a copy is one of the benefits of being a Friend; find out how to join here

The value of Richmond Park

My Chairman’s Letters tend to be about threats to the Park or the need to protect it. This time I want to celebrate it and the value it has for all of us.

The Park’s peace and tranquility restore our well-being and sanity, its wonderful views delight us, its fresh air and open grassland seem to purify us, and its fauna and flora fascinate us and make us feel connected to nature.

How should we value these benefits? Partly, of course, by how we feel after visiting the Park. But maybe also by being hard-nosed and quantifying that value.

As far as health and sanity are concerned, research shows that nature has a positive impact on mood, concentration, mental fatigue, self-discipline and physiological stress, and helps children suffering from Attention Deficit Disorder.

A large UK study found that all groups, irrespective of income, have an improvement in health in direct proportion to their access to green space, with the biggest benefit to lower income groups. Where people have good access to green space they are 24% more likely to be physically active; those who don’t are 27% more likely to be overweight or obese.

The delightful views can also be valued. Research in the Netherlands showed that merely overlooking a normal urban park increases property values by 10% (it may be considerably more in the area of Richmond Park!).

If the fresh air and open grassland seems to purify us, they also purify the climate. The 130,000 trees in the Park absorb the carbon dioxide we create; the landscape retains water rather than creating run-off as our streets do; and the woodlands and grassland cool the surrounding urban space.

Valuing biodiversity – the fauna and flora – is more difficult. Usually, people point to the medicines and materials that have been derived from the natural world, such as aspirin. We also have a vague feeling that we have a duty of care, as the most developed species, for all the species on the planet.

But biodiversity can also have a direct value for us. A recent study in Sheffield found that the psychological benefits gained by visitors to urban green spaces increased with their biodiversity, indicating that 'greenness' alone is not sufficient. You only have to compare Richmond Park with a local park whose biodiversity stretches to wildfowl or garden flowers to feel that this must be true.

The National Ecosystem Assessment published last year, estimates that the difference between properly caring for green spaces, both urban and rural, and neglecting them is worth £50 billion a year or almost £1,000 per person – something to think about when you are next admiring the views in the Park.

Ron Crompton