ALBERT

Description:    Rewetting can strongly affect the matter balance of peatlands. Owing to evidence of increasing CH 4 emissions and P mobilisation after rewetting, the effects of peatland restoration on climate, eutrophication risks and related controversies are discussed. Our study focuses on the role of helophytes in the carbon and nutrient balance of rewetted fen grasslands of NE Germany. We hypothesise that the helophytes Carex riparia , Glyceria maxima , Phalaris arundinacea , Phragmites australis and Typha latifolia differ in biomass production and nutrient standing stock according to site conditions and harvest time. We analysed the helophyte biomass three times a year and continuously measured water levels and quality. Biomass production, nutrient standing stock and litter accumulation were highly species specific and depended on nutrient availability, mean water levels and harvesting time. We conclude that helophytes store considerable amounts of carbon and temporarily improve the water quality by withdrawing high amounts of nutrients from the top soil during the growing season, and by reducing nutrient discharges. Restoring peatlands as effective nutrient and carbon sinks in the landscape should favour highly productive potentially peat-forming helophytes as Phragmites australis by establishing adequate water levels. If nutrients are to be removed from the degraded peatland, then management can combine the restoration of helophyte stands by rewetting with harvesting measures. Content Type Journal Article Pages 1-16 DOI 10.1007/s10750-011-0782-5 Authors Karsten Schulz, Institute of Botany and Landscape Ecology, University of Greifswald, Grimmer Str. 88, 17487 Greifswald, Germany Tiemo Timmermann, Institute of Botany and Landscape Ecology, University of Greifswald, Grimmer Str. 88, 17487 Greifswald, Germany Peggy Steffenhagen, LUP—Luftbild Umwelt Planung GmbH, Große Weinmeisterstraße 3a, 14469 Potsdam, Germany Stefan Zerbe, Faculty of Science and Technology, Free University of Bozen-Bolzano, Piazza Università 5, 39100 Bolzano, Italy Michael Succow, Michael Succow Foundation, Institute of Botany and Landscape Ecology, Grimmer Str. 88, 17487 Greifswald, Germany Journal Hydrobiologia Online ISSN 1573-5117 Print ISSN 0018-8158