EPA - Ireland's Environment, An Integrated Assessment - 2020

Ireland’s Environment – An Integrated Assessment 2020 Soils, Land Management and Carbon Sequestration In Ireland, land use, land use change and forestry (LULUCF) is a net source of CO 2. , but this needs to be reversed so that land is used to store carbon to meet greenhouse gas and carbon neutrality targets. Healthy soils play a role in carbon sequestration from the atmosphere. Land management activities can help or hinder carbon sequestration in soils. Overall, LULUCF in Ireland is a net source of CO 2 , with net emissions of 3.3 million tonnes CO 2 equivalent in 2018 (EPA, 2020a). Previous Environmental Protection Agency (EPA)-funded research has suggested that there is significant potential for carbon sequestration by soils used for growing crops and grasses (Kiely, et al. , 2017). More recently, Teagasc indicated that much of our grassland soil is already high in carbon, with little change in this carbon stock in recent years. Teagasc also highlighted the importance of protecting the carbon already sequestered and indicated that the largest potential for increased carbon sequestration is in the rewetting of organic agricultural soils (Lanigan and Donnellan, 2019). Peat-rich soils, such as in bogs, for example, are usually good at sequestering and storing carbon; however, if they are drained and dried out, this process is reversed, and they emit carbon back into the atmosphere. A recent EPA-funded research project, the Soil Organic Carbon and Land Use Mapping (SOLUM) project, 1 combines high-resolution spatial data, Teagasc’s Soil Information System and remote sensing tools with the aim of providing a verifiable land use and soils inventory for Ireland. Additionally, recent research from Teagasc is assessing the importance of subsoils for carbon sequestration (Simo et al. , 2019). In a special report on climate change and land (IPCC, 2019), the Intergovernmental Panel on Climate Change affirmed that sustainable land management helps to prevent and reduce land degradation. It also maintains land productivity and may contribute to reversing the negative impacts of climate change. Sustainable land management can be progressed by integrating climate- and land-related policies and fostering engagement and collaboration between different sectors, thus saving resources, improving social resilience and supporting ecological restoration. While effective land management is one element that can contribute to climate mitigation, reducing greenhouse gas emissions across all sectors is needed if global warming is to be kept below 2°C, if not 1.5°C. This is discussed in more detail in Chapter 2. Responding to climate 1 https://epasolumproject.wixsite.com/solum change and reducing greenhouse gas emissions involves many different sectors working together. It is therefore important that land use and sectoral planning become more integrated and coordinated across multiple sectors, in a national effort to address environmental challenges consistently. Soil and Water Management Properly managed soils can act as a trap to hold on to nutrients and as a sponge to hold back water flows, minimising flooding risks. Soils play an important role in filtering water as it travels through the ground. Soils also hold onto nutrients and store them for release later. Wetland areas help store, move and filter water at the surface. They are also able to remove excess nutrients, such as nitrogen and phosphorus, and sediments, and play an important role in natural flood management, by slowing the movement and release of flood waters. Water pollution can be reduced by using and maintaining urban and rural sustainable drainage systems and limiting nutrient run-off from soils and surfaces in rural areas. Nutrients and soils that enter our waters can impact on water quality by chemically or physically changing water body conditions, which in turn can affect aquatic plants and animals, particularly those that are sensitive to changes in their environment. Chapters 6 and 7 provide more information on land use pressures affecting nature and water quality. 100