Lakes: a new concept for wildlife conservation on Irish cutaway peatlands

Authors:
H. Lally, T. Higgins, E. Colleran and M. Gormally

Book:
After Wise Use – The Future of Peatlands, Proceedings of the 13th International Peat Congress: Peatland After-Use

Keywords:
biodiversity, conservation-potential, cutaway-peatlands, lake-creation, trophic-status

Documentfile:
Lally et al. 2008: Lakes: a new concept for wildlife conservation

Summary:

By 2030, Ireland will have more than 80,000ha of cutaway peatlands. Since the early 1990s, lake creation has emerged as a novel post-harvesting land use option for industrial peatlands. It is probable that up to half of all emerging cutaway peatlands in Ireland will be flooded and revegetated for conservation and public amenity uses, in one of the largest wildlife habitat creation projects in Europe in modern times. Here we review the Irish experience of creating lakes and wetlands on cutaway peatlands and describe some of the lessons learned. Baseline water chemistry data are presented for 13 lakes created in the pilot Lough Boora Parklands project in County Offaly. Physicochemically, the cutaway waterbodies lie along a gradient from acidic, dystrophic, humic lakes to alkaline, minerotrophic, clear water lakes. Data suggested that the hydrologic regime and type and depth of the residual peat sediment, both of which are determined by the construction approaches adopted, were the main determinants of water chemistry. In terms of trophic status, most cutaway lakes were slightly eutrophic- mesotrophic although certain sites were eutrophic-hypereutrophic, indicating elevated nutrient enrichment. Nutrient concentrations in the artificial lakes appeared to be influenced primarily by catchment land uses. Col- lectively, the research findings will help to provide guidelines aimed at maximising the conservation value and biodiversity potential of future cutaway lake creation projects.