Ascertaining the nature and timing of mire degradation: using palaeoecology to assist future conservation management in Northern England

Abstract

Large areas of upland mire and moorland in Northwest Europe are regarded as degraded, not actively peat-forming, and releasing carbon. Conservation agencies have short-term targets to restore such areas, but often have no clear knowledge of the timing and nature of degradation. It has been suggested that palaeoecology can be used to inform conservation management about past vegetation states, so as to help identify feasible restoration targets. Our research study in northern England, commissioned by the national statutory conservation agency, applied multiple palaeoecological techniques to establish the vegetation history of several mire and moorland sites, specifically to ascertain the nature and timing of degradation. Techniques applied included pollen analysis, plant macrofossil and charcoal analyses, determination of peat humification and mineral magnetic susceptibility, with ages ascertained using spheroidal carbonaceous particle analysis, 210Pb and 14C dating. Data are presented from case-study sites in the North York Moors, North- and South Pennines to illustrate how palaeoecology can extend long-term monitoring and guide conservation management. Palaeoecological data from a site within a National Nature Reserve, subject to exceptionally long-term (half-centennial) ecological monitoring, showed that this period does not include its pre-degradation state and that its current valued vegetation is novel and may have established after major fire. Overall, the studies suggest that the principal vegetation change at the sites took place after the start of the Industrial Revolution, and that the current landscape appearance not only has no long history, but that valued aspects, such as extensive heather moorland, feature only recently in the cultural landscape. These findings pose challenging questions for conservation management. We offer a non-specialist guide to the palaeoecological techniques that considers level of skill, cost, and comparability with ecological aspects of conservation and monitoring interest. We suggest palaeoecological data can provide valuable information and insights to aid practical conservation. While mires are particularly suitable, palaeoecological techniques could be applied in many other degraded landscapes internationally.

Keywords

• palaeoecology
• nature conservation
• plant macrofossils
• pollen analysis
• ²¹⁰Pb dating
• spheroidal carbonaceous particles
• Industrial Revolution
• degraded ecosystem
• bog
• moorland