Could Doncaster’s wetlands help the town have net zero emissions?

When she spoke at the Global Climate Strike on Friday, Mayor Ros Jones spoke of how Doncaster Council is committed to having net-zero carbon emissions.This pledge was well received and is a critical step towards tackling climate change.

Net zero carbon emissions aren’t the same as saying we will not produce any carbon dioxide, it’s saying that overall, the carbon emissions we produce will be offset somehow.The basic principle is that for every molecule of carbon dioxide we emit, we will ensure we have the capacity to capture a molecule back from the atmosphere.If you’re not emitting much carbon dioxide and you have lots of ways to capture carbon dioxide from the environment, you could end up having a net negative carbon emission.

Calculating how much carbon dioxide even one person “emits” in a year is quite tricky.Car, public transport, food and food transport, all the plastic produced, heating and lighting, clothes and shoes.

Breathing alone produces around a kilogram of carbon dioxide a day which we exhale to the air.One tree absorbs 22 kg of carbon dioxide per year.We need 17 trees each, just to offset our breathing so just how can we manage to get to net-zero emissions as a town?Figures show that Doncaster carbon emissions have already fallen from 9.4 to 3.5 tonnes per capita between 2005 and 2017.All categories fell in this time except for one, other transport, which may be the airport.The national average in 2017 was 5.3 tonnes per capita with the city of London racking up 118.5 tonnes per capita in 2016 (2017 figures not available).

Of all the global vegetation, wetlands, northern forests and grasslands are thought to store the most carbon and estimates are that UK grassland stores one million metric tonnes of carbon to a depth of one meter.

These stores of carbon have been found to be higher in grasslands which weren’t intensely managed, in habitats with more diversity in plants.Wetlands in cooler climates, like ours, are also responsible for huge stores of carbon, keeping the greenhouse gas out of the atmosphere.Storing the carbon in the soil and sediment means it is “safer” than trees which can be victim to fires all too easily.

If you look at an aerial map of Doncaster it’s clear that we’re quite wet.There are wetlands and grasslands surrounding the town on all sides.

Thorpe Marsh and Potteric Carr are great places of nature and biodiversity and they store tonnes of carbon dioxide.We’re lucky our environment is well suited to this type of carbon store.If we want to keep the carbon in the ground, or more so, want to capture more carbon from the atmosphere into the ground then we need to protect the unmanaged, or minimally managed, grasslands and wetlands around our town and where possible, we need to create or reclaim more.

In protecting grassland and wetland, we can ensure that carbon is not released into the environment through the destruction of biodiverse habitats.Creating new, or developing existing grasslands and wetlands has the potential to offset tonnes of carbon dioxide which we, as a town, are releasing into the atmosphere.A solution to offsetting carbon emissions which suits our land perfectly has got to be more appealing than mechanical carbon capture and if we get it right, and achieve net-zero or better, we can even sell our surplus carbon offset to the highest bidder.