posted on 2016-06-08, 15:45authored byMark A. Stevenson, Suzanne McGowan, Nicholas John Anderson, Robert H. Foy, Peter R. Leavitt, Yvonne R. McElarney, Daniel R. Engstrom, Sergi Pla-Rabes
Planted forests are increasing in many upland regions worldwide, but knowledge about their potential effects on algal communities of catchment lakes is relatively unknown. Here, the effects of afforestation were investigated using palaeolimnology at six upland lake sites in the north-west of Ireland subject to different extents of forest plantation cover (4–64% of catchment area). 210Pb-dated sediment cores were analysed for carotenoid pigments from algae, stable isotopes of bulk carbon (δ13C) and nitrogen (δ15N), and C/N ratios. In lakes with >50% of their catchment area covered by plantations, there were two- to sixfold increases in pigments from cryptophytes (alloxanthin) and significant but lower increases (39–116%) in those from colonial cyanobacteria (canthaxanthin), but no response from biomarkers of total algal abundance (β-carotene). In contrast, lakes in catchments with <20% afforestation exhibited no consistent response to forestry practices, although all lakes exhibited fluctuations in pigments and geochemical variables due to peat cutting and upland grazing prior to forest plantation. Taken together, patterns suggest that increases in cyanobacteria and cryptophyte abundance reflect a combination of mineral and nutrient enrichment associated with forest fertilization and organic matter influx which may have facilitated growth of mixotrophic taxa. This study demonstrates that planted forests can alter the abundance and community structure of algae in upland humic lakes of Ireland and Northern Ireland, despite long histories of prior catchment disturbance.
History
School
Social Sciences
Department
Geography and Environment
Published in
GLOBAL CHANGE BIOLOGY
Volume
22
Issue
4
Pages
1490 - 1504 (15)
Citation
STEVENSON, M.A. ... et al, 2016. Impacts of forestry planting on primary production in upland lakes from north-west Ireland. Global Change Biology, 22 (4), pp.1490-1504
This work is made available according to the conditions of the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International (CC BY-NC-ND 4.0) licence. Full details of this licence are available at: https://creativecommons.org/licenses/by-nc-nd/4.0/
Publication date
2016
Notes
This is the peer reviewed version of the following article: STEVENSON, M.A. ... et al, 2016. Impacts of forestry planting on primary production in upland lakes from north-west Ireland. Global Change Biology, 22 (4), pp.1490-1504, which has been published in final form at http://dx.doi.org/10.1111/gcb.13194. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Self-Archiving