Background
This long-term experiment is located at Hard Hill on the Moor House National Nature Reserve in the north Pennines. Situated at between 580m and 630m above sea level in Upper Teesdale, the experiment was initiated over 60 years ago in 1954 and has been running ever since.
Moorlands and in particular blanket bogs which occur on peats with a depth greater than 0.5m are of high priority conservation interest. They also provide a range of ecosystem services including carbon sequestration, provision of drinking water, livestock production (sheep grazing) and sporting interests (in the form of red grouse shooting). To increase the productivity for both sheep and grouse, moorlands are managed by rotational burning.
The experiment was set up to investigate the effects of vegetation management by grazing and long-term rotational burning on blanket bog vegetation and has been maintained throughout by Natural England (NE) and its predecessor bodies.
Since 1992, the site has also been monitored by the Environmental Change Network (ECN) through the Centre for Ecology and Hydrology (CEH).
Experimental Design
The experiment consists of four replicate blocks measuring 90m by 60m and divided into six 30m by 30m cells. Each block has two grazing treatments (fenced and grazed) and three rotational burning treatments (burnt in 1954 only, burnt at 20-year intervals and burnt at 10-year intervals), giving a total of six treatments. These treatments are arranged in a randomized block split-plot design, pictured below through an aerial view.
aerial view of blocks a-d, uphill from bottom to top
Results and Recommendations
Vegetation composition and individual species abundance reflected the degree of disturbance. The least disturbed was dominated by Calluna vulgaris and pleurocarpous mosses, whereas the most disturbed treatment (burned every 10 years) had greater Eriophorum vaginatum, Sphagnum spp., acrocarpous mosses, liverworts, and lichens. The 20‐year treatment was intermediate in response disturbance. Repeated burning increased species abundance‐weighted Ellenberg values for moisture, reaction, light through time, and fertility; the exception was the 10‐year rotation for fertility. These confirm that prescribed burning does not exclude peat‐forming species (Eriophorum spp. and Sphagnum spp.). In fact these species were found in greater abundance in frequently burned treatments. It also confirms that a no‐burn policy will lead to increasing dominance of C. vulgaris, a flammable, fire‐adapted shrub, which increases summer wildfire risk.
These results inform conservation management policy for moorland vegetation growing on peat; for this site, a 20‐year prescribed burning rotation is recommended.
Further Information and Data Archive
Further site information and regular vegetation monitoring data are available from the CEH Environmental Data Centre, and also the CEH website.
The Moor House plots are available as a platform for other researchers to use in collaboration with CEH. If you wish to make use of the plots for ecological research, please contact Martin Furness in the first instance.
