Friday, 2 September 2016

Irish distribution of High Nature Value farmland

The IDEAL-HNV project has been investigating the distribution and extent of High Nature Value farmland in Ireland. Our latest article in the Journal of Maps (Matin et al. 2016) presents a map of the predicted distribution of HNV farmland in Ireland.

Update 6th April 2017:
 
What is High Nature Value farmland and why is it important?
High Nature Value (HNV) farmland has been defined as “those areas in Europe where agriculture is a major (usually the dominant) land use and where agriculture sustains or is associated with either a high species and habitat diversity, or the presence of species of European conservation concern, or both”. Maintaining both the nature value of this farmland and the livelihoods of farmers in these areas is a key policy challenge in the years ahead. The European Commission includes HNV farming and forestry systems as one of the seven headline indicators of environmental impact. Member States are required to identify areas with HNV farming practices, to support and maintain HNV farming through Rural Development Programmes, and monitor changes to HNV farmland area over time.



Predicting the Irish distribution of HNV farmland
The IDEAL-HNV project developed Geographical Information System (GIS) methods to improve prediction of the likely distribution of HNV farmland. We mapped the likely distribution of HNV farmland based on established European indicators adapted for Ireland using the following indicators:
·               Semi-natural land cover classes from Corine 2012
·               Stocking density from the Department of Agriculture, Food and the Marine
·               Percentage hedgerow cover 
·               Length of river and stream from Ordinance Survey Ireland river-stream map
·               Soil diversity calculated using the Teagasc map of soil associations
Data were modelled at the tetrad scale (2km x 2km), and presented here at the scale of Electoral Divisions. The resulting map (from Matin et al., 2016) indicates the likely occurrence and distribution of HNV farmland in each Electoral Division, based on a scale ranging from very low (blue colour) to intermediate (yellow) to very high (green) (Figure 1).

Benefits and potential impacts
To our knowledge, this is the first Irish national-scale map that has used objective agri-environmental criteria to predict the likely distribution of HNV farmland. This provides a reference point for the future monitoring of the distribution of HNV farmland in Ireland. It can also assist in policy planning and development for the rural environment. For example, comparisons of the spatial distribution of HNV areas and the spatial distribution of agri-environmental and other payments can assess the degree to which payments are targeted toward HNV farming systems. In addition, these data can be used to incorporate impacts on farmland biodiversity of, for example, land use change and climate change in national-scale models or scenarios.

Caveats...
As an indicator-based prediction, such maps should be interpreted within the limitations of the data used. The spatial scale of the map is restricted by the coarse scale of data at national level. Given the predictive and aggregated nature of the outputs, it is important to note that non-HNV farmland may still occur in areas with high likelihood of HNV farmland, and vice versa. We also know that some very specific types of HNV farmland are not well-represented by this approach. For this reason, this output is not suitable for strictly deciding whether farmers in certain areas should be eligible or not for agri-environmental measures aimed at HNV farming systems. Instead, there is a requirement for a farm-scale assessment to confirm the HNV of individual farms. As part of the IDEAL-HNV project, we also examine the farm-scale characteristics of HNV farmland. See the project website (www.high-nature-value-farmland.ie) for further details.

REFERENCE
S. Matin, C. A. Sullivan, D. Ó hUallacháin, D. Meredith, J. Moran, J. A. Finn, and S. Green 2016. Predicted distribution of High Nature Value farmland in the Republic of Ireland. Journal of Maps http://www.tandfonline.com/doi/abs/10.1080/17445647.2016.1223761


Update 6th April 2017:
Our online map viewer (note different colour scheme) allows you to click on individual Electoral Districts and view the score.
Users can upload the data onto their GIS directly from this link: