Grass fields can become ‘sinks’ for soaking up greenhouse gases
The research undertaken by Teagasc and University College Cork over a five-year period in the south-east and south-west showed ordinary grass fields could provide important “sinks” for soaking up CO2.
Carbon dioxide is considered the most offensive greenhouse gas (GHG) causing climate change.
Scientists found that every hectare of grassland can remove between 11 tonnes and 18 tonnes of carbon dioxide from the air.
A natural peatland site in Co Kerry was also found to be a “small sink” for CO2 while research on croplands will be published shortly.
Much of the grass examined in the research will go on to become silage or animal feed but it is estimated that 10%-15% of the carbon is sequestered into the soil, where it can remain for longer periods, thereby providing a positive environmental benefit.
EPA director Laura Burke said these are important results “as grassland is the dominant land use in Ireland and these results show that management of Irish grassland can have an important role in addressing climate change”.
“The outcome of this research is an important step-up in our understanding of greenhouse gases. Ireland has more than three million hectares of managed grassland. If this result were replicated across this area it would amount to a considerable sink.
“However, some other land uses are likely to be a source of carbon dioxide so a simple scaling up of these data can be misleading. Overall, the main message is positive and we need to use these results to inform decisions on the future use of grassland and other land,” she said.
EPA senior scientific officer Frank McGovern said this research needs to be considered when decisions are being made on land use and management.
“These results need to be cross-checked and other land and soil types explored. A better understanding of the dynamics of soil carbon as well as of future climate conditions on soil is also a requirement,” he said.
“This work is a key part of the EPA research programme.”
