Optimizing Carbon Storage Within a Spatially Heterogeneous Upland Grassland Through Sheep Grazing Management
Livestock grazing is known to influence carbon (C) storage in vegetation and soil. Yet, for grazing management to be used to optimize C storage, large scale investigations that take into account the typically heterogeneous distribution of grazers and C across the landscape are required. In a landscape-scale grazing experiment in the Scottish uplands, we quantified C stored in swards dominated by the widespread tussock-forming grass species Molinia caerulea. The impact of three sheep stocking treatments (‘commercial’ 2.7 ewes ha−1 y−1, ‘low’ 0.9 ewes ha−1 y−1 and no livestock) on plant C stocks was determined at three spatial scales; tussock, sward and landscape, and these data were used to predict long-term changes in soil organic carbon (SOC). We found that tussocks were particularly dense C stores (that is, high C mass per unit area) and that grazing reduced their abundance and thus influenced C stocks held in M. caerulea swards across the landscape; C stocks were 3.83, 5.01 and 6.85 Mg C ha−1 under commercial sheep grazing, low sheep grazing and no grazing, respectively. Measured vegetation C in the three grazing treatments provided annual C inputs to RothC, an organic matter turnover model, to predict changes in SOC over 100 years. RothC predicted SOC to decline under commercial sheep stocking and increase under low sheep grazing and no grazing. Our findings suggest that no sheep and low-intensity sheep grazing are better upland management practices for enhancing plant and soil C sequestration than commercial sheep grazing. This is evaluated in the context of other upland management objectives.
Keywords:livestock grazing Molinia caerulea RothC soil carbon spatial heterogeneity upland
- Bates DM, Maechler M. 2010. lme 4. Linear mixed-effects models using S4 classes. http://lme4.r-forge.r-project.org/. Accessed 21 March 2013.
- Bunce RGH, Barr CJ. 1988. The extent of land under different management regimes in the uplands and the potential for change. In: Usher MB, Thompson DBA, Eds. Ecological change in the uplands. Oxford: Blackwell Scientific Publications. p 415–26. Special Publication 7 of the British Ecological SocietyGoogle Scholar
- Carey PD, Wallis S, Chamberlain PM, Cooper A, Emmett BA, Maskell LC, McCann T, Murphy J, Norton LR, Reynolds B, Scott WA, Simpson IC, Smart SM, Ullyett JM. 2008. Countryside Survey: UK Results from 2007. NERC/Centre for Ecology & Hydrology, 105 pp. (CEH Project Number: C03259).Google Scholar
- Coleman K, Jenkins D. 1999. RothC-26.3. A model for the turnover of carbon in soils. Model description and Windows Users Guide. Harpenden: IACR, Rothamsted.Google Scholar
- Dennis P, Elston D, Evans D, Evans D, Evans S, Gordon I, Grant M, Kunaver A, Marquiss M, Mayes B, McCracken D, Pakeman R, Pearce-Higgins J, Redpath S, Skartveit J, Stephen L, Benton T, Bryant D. 2004. Effects of grazing management on upland bird populations: disentangling habitat structure and arthropod food supply at appropriate spatial scales (GRUB). Edinburgh: Scottish Executive Environment & Rural Affairs Department. pp 1–57.Google Scholar
- Grant SA, Maxwell TJ. 1988. Hill vegetation and grazing by domesticated herbivores: the biology and definition of management options. In: Usher MB, Thompson DBA, Eds. Ecological change in the uplands. Oxford: Blackwell Scientific Publications. p 201–14. Special Publication no. 7 of the British Ecological SocietyGoogle Scholar
- Guo L, Fallon P, Coleman K, Zhou B, Li Y, Lin E, Zhang F. 2007. Application of the RothC model to the results of long-term experiments on typical upland soils in northern China. Soil Use Manag 23:63–70.Google Scholar
- Latusek E 1983. The autecology of Molinia caerulea (L.) Moench with particular reference to grazing. Unpublished PhD thesis, Manchester Polytechnic, Manchester, UK.Google Scholar
- Morgan-Davies C, Waterhouse A. 2008. Hill and upland areas: livestock farming changes and stakeholder preferences. Aspects Appl Biol 85:49–56.Google Scholar
- R Development Core Team. 2009. R: a language and environment for statistical computing. R Foundation for Statistical Computing, Vienna, Austria. ISBN 3-900051-07-0. http://www.R-project.org.
- Reed MS, Bonn A, Slee W, Beharry-Borg N, Birch J, Brown I, Burt TP, Chapman D, Chapman PJ, Clay GD, Cornell SJ, Fraser EDG, Glass JH, Holden J, Hodgson JA, Hubacek K, Irvine B, Jing N, Kirkby MJ, Kunin WE, Moore O, Moseley D, Prell C, Price MF, Quinn CH, Redpath S, Reid C, Staglo S, Stringer LC, Termansen M, Thorpp S, Towers W, Worrall F. 2009. The future of the uplands. Land Use Policy 26:204–16.CrossRefGoogle Scholar
- Rodwell JS. 1991. British plant communities. Mires and heaths, Vol. 2Cambridge: Cambridge University Press.Google Scholar
- Rodwell JS. 1992. British plant communities. Grasslands and montane communities, Vol. 3Cambridge: Cambridge University Press.Google Scholar
- Sanderson N. 1998. Glen Finglass historic landscape survey. Hythe: Woodland Trust. pp 1–104.Google Scholar
- Scottish Agriculture College (SAC). 2008. Rural Policy Centre, Farming’s retreat from the hills, Outlook for 2009. p. 1–32.Google Scholar
- Smith P, Smith JU, Powlson DS, McGill WB, Arah JRM, Chertov OG, Coleman K, Franko U, Frolking S, Jenkinson DS, Jensen LS, Kelly RH, Klein-Gunnewiek H, Komarov AS, Li C, Molina JAE, Mueller T, Parton WJ, Thornley JHM, Whitmore AP. 1997. A comparison of the performance of nine soil organic matter models using datasets from seven longterm experiments. Geoderma 81:153–225.CrossRefGoogle Scholar
- Soil Indicators for Scottish Soils (SIFSS). 2013. The James Hutton Institute. http://sifss.hutton.ac.uk/index.php. Accessed 28 June 2013.
- Soil Survey of Scotland. 1984. Organisation and methods of the 1:250000 scale soil survey of Scotland. Aberdeen: Macaulay Institute for Soil Research.Google Scholar
- Thornton B. 1991. Effect of nutrition on the short-term response of Molinia caerulea to defoliation. Ann Bot 68:569–76.Google Scholar
- UK Meteorological Office. MIDAS Land Surface Stations data (1853–current), [Internet].NCAS British Atmospheric Data Centre, 2006, Date of citation. http://badc.nerc.ac.uk/view/badc.nerc.ac.uk__ATOM__dataent_ukmo-midas. Accessed 26 June 2012.
- Van der Wal R, Bonn A, Monteith D, Reed M, Blackstock K, Hanley N, Thompson D, Evans M, Alonso I. 2011. Mountains, moorlands and heaths. p. 105–159, In: The UK National Ecosystem Assessment Technical Report. UK National Ecosystem Assessment, UNEP-WCMC, Cambridge.Google Scholar