Risk/opportunity:(from the Climate Change Risk Assessment for Scotland 2012):
AG25/AG51/AG52 Agricultural land classification and crop suitability Cross-cutting (including changes in yields, changes in soil condition, human food supply)
Narratives: Suitability and productivity (agriculture), Sustainable agriculture
SCCAP theme: Natural environment
SCCAP objectives:
N3: Sustain and enhance the benefits, goods and services that the natural environment provides
To date no single value indicator has been developed to summarise the relationship. The most recent published figures defining the relationship are for 2011 though data to support analysis for 2000-2014 are available.
Trend
No change detection or trend analysis has been undertaken.
- Growing evidence that agricultural potential has, and is, changing in response to weather and climate.
- It is too early to tell whether there has been an associated change in land use.
- The degree to which such changes occur will be governed by a complex mix of biophysical, economic and social factors which will vary in space and over time.
There is a growing body of evidence that the agricultural potential as defined by the Macaulay system of Land Capability for Agriculture (LCA) has, and is, changing in response to weather and climate (Brown et al., 2008). Given that land use potential is changing in Scotland, there is interest in better understanding how these changes in potential may relate to actual changes in land cover, use and/or management. Intensification of production could be associated with increased pressures on the natural environment, though the balance of outcomes would depend heavily on the precise circumstances, land use systems and relative valuations of ecosystem services (provisioning vs. others) and beneficiaries (public vs. private).
Related indicators:
Maps of land capability and land use/cover derived from Scottish Government’s Integrated Administration and Control System (IACS) have been combined to derive breakdowns of the mix of land use/cover for each of the LCA classes (Table 1), as shown in Figures 1 and 2 below (the first showing areas and the second proportions per LCA class). The most recent version of the analysis published is for the year 2011 (Miller et al., 2012)[1].
|
Class |
Category |
Climate limitations |
Land use |
|
1 |
Prime |
None or very minor |
Very wide range of crops with consistently high yields |
|
2 |
Prime |
Minor |
Wide range of crops, except those harvested in winter |
|
3.1 |
Prime |
Moderate |
Moderate range of crops, with good yields for some (cereals and grass) and moderate yields for others (potatoes, field beans, other vegetables) |
|
3.2 |
Non-prime |
Moderate |
Moderate range of crops, with average production, but potentially high yields of barley, oats and grass |
|
4.1 |
Non-prime |
Moderately severe |
Narrow range of crops, especially grass due to high yields but harvesting may be difficult |
|
4.2 |
Non-prime |
Moderately severe |
Narrow range of crops, especially grass due to high yields but harvesting difficulties may be severe |
|
5 |
Non-prime |
Severe |
Improved grassland, with mechanical intervention possible to allow seeding, rotavation or ploughing |
|
6 |
Non-prime |
Very severe |
Rough grazing pasture only |
|
7 |
Non-prime |
Extremely severe |
Very limited agricultural value |
Table 1 LCA classes and associated land uses (Bibby et al., 1982)
Figure 1 Area (hectares) of IACS grouped land uses by LCA class (Miller et al., 2012)
Figure 2 Proportion of IACS grouped land uses by LCA class (Miller et al., 2012)
[1] The analysis was undertaken as part of research in support of post-2015 CAP policy development rather than specifically in the context of climate change adaptation or mitigation
No analysis of past land use/cover change has currently been undertaken as part of this research.
Based on the outputs of models of future climate there are indications of possible improvements in land capability for some regions due to climate, but potentially limited by climate-soil-topography interactions. However, no projections of land use/cover response have yet been made. Changes in land use mix that could be associated with movement between capability classes can be inferred by comparison between columns in the proportions chart above (Fig. 2). The degree to which such changes occur will be governed by a complex mix of biophysical, economic and social factors which will vary in space and over time.
Since the data is generated from field-scale land use data, it is possible to generate land use/cover mixes per land capability class for regions or other localities within Scotland. To date such information has been used for illustrative rather than analytical purposes – for example for Agricultural Regions in Miller et al., (2012).
No analysis of indicator trend has currently been undertaken.
The key limitation on such an indicator is whether changes in land use/cover can be adequately attributed to climate induced changes in capability rather than other factors- environmental, economic, political and social drivers operating at local, national and international levels (e.g. changing market forces; policies to enhance biodiversity, promote forestry or renewable energy supply) (Miller et al., 2009; Slee et al., 2013). A secondary limitation is the degree to which any single indicator value can adequately reflect the diversity of system-wide, interlinked, changes occurring in a heterogeneous geographical space.
Technical limitations of the analysis relate to the two input datasets. For LCA these include: the availability of large scale (1:50,000) mapping in only 2.6M ha with another 5.1M ha covered at only 1:250,000 scale; the climate data embodied in the published mapping is for 1958 to 1978; the match between the edges of the two scales of LCA mapping and other technical issues arising from the conversion from paper to digital mapping. These are further detailed in communications with Scottish Government.
For land use/cover – mapping is available from 2000, but early coverage has a degree of bias in favour of lowland and agricultural land. Coverage has increased over time to 5.7[1] M ha in 2014 and can be supplemented with other decadal sources such as the National Forest Inventory.
The land use classifications within IACS are based on the need to administer support through particular payment schemes so there is change in classification over time. The use of IACS from 2009 as part of generating Agricultural Census data means that a fair degree of continuity can be expected in future. Since IACS is self-reported by land managers there can be issues of interpretation, for example differentiating between previously improved and semi-natural grassland.
[1] Polygon area of fields with declared land uses, 6.5M ha are included in the mapping but without land use/cover data.
Brown, I., Towers, W., Rivington, M., & Black, H.I.J. (2008) Influence of climate change on agricultural land-use potential: adapting and updating the land capability system for Scotland. Climate Research, 37, 1, 43-57.
Miller, D.G., Matthews, K.B., and Buchan, K. (2012) Future CAP Payments: Determining the land use and farm-type mixes of land capability for agriculture class groupings in the regions of Scotland and the characteristics of holdings containing both land capability for agriculture classes 1 to 5.3 and 6.1 to 7 land. Report to RESAS, available online at http://hutton.ac.uk/sites/default/files/files/ladss/LCAvsFarm-Type-and-Land-Use.pdf.
Miller, D., Schwarz, G., Sutherland, L-A., Morrice, J., Aspinall, R., Barnes, A., Blackstock, K., Buchan, K., Donnelly, D., Hawes, C., McCrum, G., McKenzie, B., Matthews, K., Miller, D., Renwick, A., Smith, M., Squire, G., Toma, L. (2009) Changing Land Use in Rural Scotland –Drivers and Decision-making. Rural Land Use Study Project 1. Report to Scottish Government, available online at http://www.scotland.gov.uk/resource/doc/298003/0092856.pdf
Slee, B., Brown, I., Donnelly, D., Gordon, I.J., Matthews, K.B., Towers, W. (2013) The ‘squeezed middle’: Identifying and addressing conflicting demands on intermediate quality farmland in Scotland, Land Use Policy, 41, 206-216.
Bibby, J. S., Douglas, H. A., Thomasson, A. J., & Robertson, J. S. (1991) Land Capability for Agriculture, The Macaulay Land Use Research Institute, Aberdeen.
Development of this indicator and primary author of this document: Keith Matthews, James Hutton Institute.
This research has been funded by Scottish Government through their strategic research programmes: Environment: Land Use and Rural Stewardship (2006-11) and Environmental Change (2011-16) and by the Contract Research Fund.
Anne Marte Bergseng
