plot markers at little budworth common lte
chris field, manchester metropolitan university
Background
Little Budworth Common is a Site of Special Scientific Interest (SSSI) owned by the Egerton Estate and managed by Cheshire West and Chester Council. It is located a few miles due east of Chester near the town of Winsford and is a rare example of lowland heath habitat in Cheshire. The experimental site is classified as H9 heather and is part of the wider Little Budworth Country Park.
Established in 1996, the experiment is testing the hypothesis that elevated atmospheric nitrogen deposition increases the sensitivity of heather (Calluna vulgaris) and its associated vegetation to environmental stresses, for example a controlled drought experiment in 1997 and natural outbreaks of heather beetle in 1998 and 1999.
Throughout its early years, the experiment was one of several sites operating under the former UKREATE umbrella project funded by the Department for Environment Food and Rural Affairs (Defra) and the Natural Environment Research Council (NERC).
Plot Treatments
Nitrogen was applied monthly to plots at rates of 0, 20, 60 or 120 kg/ha/yr N in the form of ammonium nitrate. In addition to nitrogen treatments, a summer drought treatment was established between May and September 1997 in which droughted plots were covered and received no rainfall. Subsequently, in mid-summer 1998, there was a natural heather beetle infestation at The Common which allowed the effect of elevated nitrogen on sensitivity to attack by the heather beetle to be assessed. In autumn 2002 the plots were subjected to a management cut, and the vegetation removed to a height of 10 cm, and harvested. The moss and litter layers remained intact.
Summary of Results to Date
Studies at first demonstrated significant increase in heather cover on watered plots, with a positive effect of N treatment, but later results were more ambiguous. There were also significant early increases in Deschampsia flexuosa (wavy hair-grass) in response to 120 Kg N/ha/yr with drought. Mean bryophyte cover on watered plots increased steadily through the experiment.
Leachate studies from 2000 onwards examined nitrogen flux through the soil and revealed high levels of nitrogen immobilisation in the soil and vegetation.
The results from the experiment, as with all the UKREATE umbrella sites, contributed to Defra’s guidance on nitrogen and provided the science supporting critical loads and critical levels for nitrogen. There is clear evidence that modest N loading can have significant impacts on semi-natural ecosystems and even low N inputs may induce effects over time through accumulated loading.
Further Information
Access the UKREATE publication in Global Change Biology journal.
For a more detailed review of the history of the Little Budworth Common site and experiment, listen to our on-site podcast with Principal Investigator Chris Field.
Treatments and monitoring at Little Budworth Common continue to date. If you are interested in accessing more recent data or in using this site for new collaborative research, please contact Chris Field via the link at the top of this page.
