. RESTORATION AND RECOVERY OF SPHAGNUM ON DEGRADED BLANKET BOG ANGUS EWAN ROSENBURGH DOCTOR OF PHILOSOPHY 2015 1 . RESTORATION AND RECOVERY OF SPHAGNUM ON DEGRADED BLANKET BOG ANGUS EWAN ROSENBURGH A thesis submitted in partial fulfilment of the requirements of the Manchester Metropolitan University for the degree of Doctor of Philosophy Division of Biology and Conservation Ecology School of Science and the Environment Manchester Metropolitan University 2015 2 Restoration and recovery of Sphagnum on degraded blanket bog Ever tried. Ever failed. No matter. Try again. Fail again. Fail better. – Samuel Beckett iii Abstract Abstract 1. The blanket bogs of the southern Pennines and Peak District are severely degraded, attributed to centuries of poor land management, wildfire and atmospheric pollution. Restoration efforts have focussed on the revegetation of bare and eroding peat surfaces, with considerable success. 2. Sphagnum mosses provide the form and function of blanket bog, with their remains making up the majority of the peat body. These species were lost from the region and remain largely absent, despite restoration efforts. 3. As a keystone species of peatlands, their return is essential to the continued provision of ecosystem services derived from these uplands. Hence, their reintroduction is of great importance. 4. Preliminary trials determined Sphagnum can be reintroduced to numerous degraded conditions found on blanket peat, with S. fallax the best performing species. Water availability was strongly implicated as a significant factor, with drought proving fatal to propagules. In areas of dense vegetation, flailing has the potential to increase establishment, but requires further verification. 5. Growth trials indicated the legacy of atmospheric pollution was still exerting influence upon the growth of Sphagnum. Peat from the southern Pennines region was shown to contain elevated concentration of numerous pollutant heavy metals and nutrients. A comparative study of some UK bogs demonstrated the consequences of biogeochemical characteristics, whilst further implicating the importance of water availability in degraded sites. 6. The potential of Sphagnum reintroduction to degraded sites was demonstrated, within the constraints of shorter time scales. Over longer periods, with increased experimentation and subsequent monitoring, further understanding will undoubtedly be gathered. It is essential this knowledge is shared, updated and applied by conservation agencies and parties conducting such work. iv Acknowledgements Acknowledgements Director of studies: Simon Caporn Supervisory team: Robin Sen Matt Bucker Technical staff: David McKendry Dave Groom Sue Hutchinson Graham Tinsley Amy Hall Alistair Battersby Department colleagues: Richard Payne James Rowson Chris Field Trish Linton Paul Chipman David Elliot Daphne Lai Student volunteers: Martin Kay Joshua Riggs Anna Keightley Wayne Donner Kat Sambrooks Tom Squires Felix Nwaishi Moors for the Future Partnership: Rachael Maskill Jon Walker Brendon Wittram Micropropagation Services Ltd.: Neal Wright Barbara Wright Funding: Manchester Metropolitan University Moors for the Future Partnership Co-operative Foundation Collaboration and access: United Utilities Yorkshire Water National Trust Motivation, sanity and coffee: Family, friends, and everyone along the way v List of tables Contents Abstract ................................................................................................................................................. iv Acknowledgements ................................................................................................................................ v List of figures ......................................................................................................................................... x List of tables ........................................................................................................................................ xiv Chapter 1 – Introduction ...................................................................................................................... 1 1.1 Overview ....................................................................................................................................... 2 1.2 Ombrotrophic mires ...................................................................................................................... 2 1.2.1 Formation and structure ........................................................................................................ 2 1.2.2 Blanket bog ecology ............................................................................................................... 5 1.2.3 Significance of blanket bog .................................................................................................... 6 1.3 Sphagnum ecology ........................................................................................................................ 7 1.3.1 Species distribution ................................................................................................................ 7 1.3.2 Sphagnum properties ............................................................................................................. 9 1.4 Drivers of blanket bog degradation ............................................................................................. 10 1.4.1 Overview .............................................................................................................................. 10 1.4.2 Physical erosion ................................................................................................................... 12 1.4.3 Pollution ............................................................................................................................... 13 1.4.4 Land management ................................................................................................................ 19 1.4.5 Climate change..................................................................................................................... 22 1.5 Blanket bog recovery and restoration ......................................................................................... 23 1.5.1 Environmental improvements ............................................................................................... 23 1.5.2 Natural recovery .................................................................................................................. 26 1.5.3 Managed revegetation of blanket bog .................................................................................. 27 1.6 Sphagnum reintroduction ............................................................................................................ 29 1.6.1 Reintroduction on raised bog ............................................................................................... 29 1.6.2 Reintroduction on blanket bog ............................................................................................. 30 1.7 Knowledge gaps .......................................................................................................................... 31 1.8 Research objectives ..................................................................................................................... 32 Chapter 2 – Reintroduction of Sphagnum to degraded blanket bog .............................................. 33 2.1 Introduction ................................................................................................................................. 34 2.2 Experimental aim ........................................................................................................................ 35 2.3 Sphagnum source trials ............................................................................................................... 36 2.3.1 Rationale .............................................................................................................................. 36 vi List of tables 2.3.2 Objectives ............................................................................................................................. 37 2.3.3 Methods ................................................................................................................................ 37 2.3.4 Results and analysis ............................................................................................................. 39 2.3.5 Discussion ............................................................................................................................ 45 2.3.6 Conclusion ........................................................................................................................... 52 2.4 Sphagnum bead trials .................................................................................................................. 53 2.4.1 Rationale .............................................................................................................................. 53 2.4.2 Objectives ............................................................................................................................. 54 2.4.3 Methods ................................................................................................................................ 55 2.4.4 Results and analysis ............................................................................................................. 58 2.4.5 Discussion ...........................................................................................................................