Feature: Nature-based solutions to improve climate change and air quality

Stephen Cirell, an independent consultant on climate change, low carbon and renewable energy, advises how local authorities and policy makers can incorporate nature-based solutions into their climate, biodiversity and air quality plans. 

Local authorities across the country are grappling with the triumvirate issues of climate change, biodiversity and air quality. In an article published in Air Quality News, I said that what is needed is for climate emergency action to carefully weave together climate change, biodiversity and air quality policy into a holistic and comprehensive programme of action at local level. However, it was recognised that this is not easy and in some circumstances action in one area can actually set back progress in another.

However, one area where the positive interlink is quite clear is in relation to nature based solutions. This is a generic title to cover a range of activities, most notably afforestation, peat restoration and rewilding.

The danger is that because planting trees is such an obvious example of a nature based solution, the answer can be dumbed down to just ‘plant more trees.’ Of course it this is a ridiculous over simplification and nature based solutions can be much more sophisticated in their approach. This was confirmed by Craig Bennett of the Wildlife Trusts in the Environment Journal Podcast in December.

The starting point in any venture of this kind is for the authority to have a wider climate change strategy or climate emergency declaration and to have set itself targets for reaching a position of net zero carbon. In order to know how far it has to go to reach these targets, it needs a baseline.

The baseline calculation will need to incorporate Scope 1, 2 and 3 emissions (both direct and indirect) which is essentially undertaken by analysing data from litres of fuel oil used, heating and insulation of buildings and so on. Those authorities with large asset bases and big fleets will inevitably have higher baseline emissions and further to go to reach net zero.

Once the baseline has been completed, a climate change action plan needs to be put in place. I have commented before that these are often stronger on the climate change elements, but weaker on biodiversity and sometimes do not cover air quality at all. This needs to be remedied.

Of the actions included in such plans a distinction can be drawn between those elements that avoid emissions occurring, such as energy efficiency works to buildings and more renewable energy; compared to those that reduce emissions by removing greenhouse gases from the atmosphere. For those who are not supporters of chemical processes such as carbon capture and storage from the continuing burning of fossil fuels, nature based solutions are the go to answer for the latter.

Nature based solutions are a strong part of what local authorities already do. They have parks, playing fields, highway verges and trees to maintain and grounds maintenance has been an important part of their functional areas for decades. They also own extensive land, sometimes in the form of County Farms, let to tenant farmers on a yearly basis.

As the necessity for more extensive carbon sinks grows, local councils have been looking more carefully at their grounds maintenance operations and taking stock of how such activities can be moulded into a wider carbon plan.

An obvious example would be afforestation on land that the council owns. This not just planting any old tree on a piece of land, though, but instead needs to be part of a properly considered plan to utilise land in the best way. So it needs to be the right tree, planted in the right place and managed in the right way. Different trees have different capabilities for carbon sequestration but local and regional trends also need to be properly considered. Forests of a certain size and type can maximise the benefits in purely carbon terms, whilst obviously boosting nature and biodiversity at the same time.

Peat restoration is only relevant in some areas, but peat has an even more impressive record of carbon storage and efforts are afoot across the land to increase this work. In some instances this means filling in drainage channels that have ill-advisedly been dug. Such work dries out the peat and greatly reduces its impact as a carbon sink. In other examples, trees have been planted on peat, which again is not in keeping with its benefits to climate change.

Other types of nature based solutions would include so called ‘re wilding.’ This is the difference between a golf course and an area of scrub land. The former is superficially attractive. It is ‘green’, but is manicured, maintained by chemicals and therefore human-made and unnatural; the latter is allowing nature to take its course, with all of the insect, bird and animal benefits. The UK needs more of the latter.

Wildflower meadows are another example. These have gained prominence recently with the growth in solar farm development. A solar farm has to have security fencing around it and so becomes a secure area not visited by the public for 25 years. Instead of laying grass underneath the panels, the new way is to include a wildflower meadow. Such meadows require virtually no maintenance and so become havens for nature, from bees pollinating the flowers to insects and animals. The latest innovation is making roundabouts and highway verges wildflower areas too, although the public have to understand that this means at certain times of the year they will appear unkempt and offering little visual amenity.

The real benefits of nature based solutions are that they provide a carbon sink. As every child learns in school, plants rely on a process called photosynthesis to use the energy from light in order to convert carbon dioxide and water into carbohydrates (which are needed as building blocks for plant growth) and oxygen (as a waste product). So trees literally suck in CO2 and breathe out oxygen. Thoughts of the Amazon forest (sometimes referred to as ‘the Earth’s lungs’) being systematically destroyed in Brazil should therefore send a shiver down the spine of every environmentalist.

Different plants have different characteristics, so that forests are a better carbon sink than a grassed area for example. This is why there is such a focus on afforestation as part of such plans.

There are other significant benefits, which amply illustrate the overlap of the triumverate mentioned above. The carbon sink benefits climate change and emissions targets. The nature based solutions promote biodiversity and reverse the process of species decline. Air quality is obviously a beneficiary too, as air with less emissions and more oxygen will help the UK reach World Health Organisation guideline levels. Last – and certainly not least – health and wellbeing are greatly promoted by nature. There is considerable evidence that those fortunate to live near green space have a better wellbeing than those that do not.

So it is easy to see why there is a focus in local government at present on nature based solutions to climate change. Fortunately, this work has widespread benefits across other areas and it is this that makes it so important that local authorities wholeheartedly engage in more of this work.

Photo by Tom Rickhuss and Gaston Roulstone