Impacts of restoration of forestry-drained peatlands on nutrient and organic carbon exports and methane dynamics

Abstract

3Koskinen M. (2016). Impacts of restoration of forestry-drained peatlands on nutrient and organic carbon exports and methane dynamics. Dissertationes Forestales 232, 36p. http://dx.doi.org/10.14214/df.232In this study, the effects of restoration of forestry-drained peatlands on the nutrient and organic carbon exports and methane dynamics of the restored sites are explored. The study consists of four sub-studies. Two of the sub-studies are concerned with the effects on water quality and export of elements of restoration and were conducted on a catchment scale. One of the studies was conducted in the laboratory, and assessed the release of elements from peat samples under anaerobic inundation simulating the effects of a rising water table after restoration or logging. The fourth study was again a field study, in which the differences in methane emissions between undrained, drained and restored spruce swamp forests were assessed. In all, 24 different pristine, drained and restored sites are featured in the study, one site being present in two of the sub-studies.The results indicate potentially large effects of restoration especially on the nutrient rich spruce-dominated sites, which had the highest restoration-induced increases in organic carbon and nutrient exports in the catchment studies, and which also exhibited high methane emissions after restoration, higher than in the undrained or drained state. The results should prompt research into the techniques applied in restoration of such sites and into the processes which lie behind these large effects. After that I had a period of several years of no chance to work on the PhD project, during which I was given the chance to work on greenhouse gas measurement methodology by Dr. Kari Minkkinen. Under his supervision I learned programming, gas measurements, statistics and scientific writing. I also worked with Dr. Paavo Ojanen from the department, as well as with Dr. Annalea Lohila from the Finnish Meteorological Institute. Great times were had. Thank you for tolerating my temperament during the field work, and Paavo especially for all the conversations over the years.The good will of Prof. Eeva-Stiina Tuittila, now in the University of Eastern Finland, was instrumental for the methane study. I also want to thank our field workers, Jyri Mikkola, Mirkka Kotiaho, Janne Sormunen and Salli Uljas. Dr. Liisa Maanavilja provided insight on the sites. PhD candidate Maija Lampela assisted me with topographical measurements in the field.When it seemed improbable that I could ever make a thesis on the water quality effects of restoration of forestry-drained peatlands, Dr. Mika Nieminen from the Natural Resources Institute (then METLA) got a grant from the Maj and Tor Nessling foundation to do just that, and asked me if I would be the N.N. for whose work the funds had been granted. I said yes, and haven't regretted it. He has taught me a lot on getting work published. I have also had the opportunity to work with PhD candidate Annu Kaila, whose painstaking laboratory work and theo...