Carbon Sequestration and Loss (Carbon Flux) - 2023

This layer identifies some of the strategic opportunities in your area for positive change and work out plans with land managers to enhance carbon, whatever the current land use. It will help you understand whether you are aiming to increase carbon by a smaller amount over a large area or concentrate on a couple of smaller schemes where there will be a large enhancement such as tree planting on low intensity (species poor) grassland. In this layer we have followed the IPCC methodology for reporting carbon emissions . Emissions are recorded as a positive value as they are adding to the carbon burden in the atmosphere. Sequestration is recorded as a negative value as it is removing carbon from the atmosphere.Carbon sequestration maps shows where the environment is actively capturing carbon dioxide and binding it in plants and soils. What is being captured now with the current land use, habitats and crops. As sequestration is much more dependent on land use and management practices which vary more widely this data is only a guide for broad trends not local differences in management. i.e. where woodland or grassland cover is consistent not variation between farming practices in fields or woodland management at a local area. It is measured as tonnes of carbon dioxide equivalent per hectare per year (t CO2e ha-1 y-1 ).Many areas in agricultural production will have a neutral carbon balance where land management is sufficient to replace carbon lost in cropping or grazing from the vegetation and tillage from the soil. However, some soil types are very vulnerable to losing carbon when actively managed, these includes the very fertile but deeplowland agricultural peats. The figures for habitat sequestration of carbon are taken from the Natural England Report NERR094 (Gregg et.al. 2021). This report identified some key gaps. Each habitat type was assigned a likely score for sequestration. Carbon sequestration is less researched and harder to measure and therefore the confidence in this dataset is lower than in the carbon storage dataset.

Three data component layers were collated together to form a continuous habitat data layer for England: The National Forest Inventory (2016); NE priority habitat Inventory (PHI) dataset (various dated); Living England habitat map from satellite imagery (2020). Each of the habitats was assigned a likely sequestration value. Management influences sequestration, additional data sets adjust the figures and hence outputs spatially this included:

• the protected site data given a slight uplift to the scores;
• woodland sites on very steep slopes a slight reduction was given;
• if mineral soils had native vegetation designated by the PHI, values were slightly uplifted;
• soil type is important to sequestration with peatland soils losing carbon under arable and intensive grasslands at an extremely fast rate.
• The peatland maps were combined with the vegetation maps to highlight these areas. Management of soil in intensive pastoral and arable peat systems has a profound effect on soil carbon values.
• It is easy to lose carbon repeatedly from a system due to ploughing. For this report we have therefore assumed that these productive systems have a neutral carbon sequestration result. This is an over simplification and for more detailed studies information about the types of management regimes and more detailed soil information would be needed to understand if these areas are a carbon source or sink. NE PHI/ Ancient Woodland - OGL NE Living England - OGL NE Peatmap [2008] - Non- comercial licence NE SSSI data NFI-National Forest Inventory (NFI) Forest Reserach- OGL Soilscapes - Cranfield University/ HMSO- NE Bespoke Licence SRTM- NASA ShuttleRadar Topography- Open Topography