Skip to main content
Research article - Peer-reviewed, 2009

Photosynthetic performance in Sphagnum transplanted along a latitudinal nitrogen deposition gradient

Granath, Gustaf; Strengbom, Joachim; Breeuwer, Angela; Heijmans, Monique M. P. D.; Berendse, Frank; Rydin, Hakan


Increased N deposition in Europe has affected mire ecosystems. However, knowledge on the physiological responses is poor. We measured photosynthetic responses to increasing N deposition in two peatmoss species (Sphagnum balticum and Sphagnum fuscum) from a 3-year, north-south transplant experiment in northern Europe, covering a latitudinal N deposition gradient ranging from 0.28 g N m(-2) year(-1) in the north, to 1.49 g N m(-2) year(-1) in the south. The maximum photosynthetic rate (NP(max)) increased southwards, and was mainly explained by tissue N concentration, secondly by allocation of N to the photosynthesis, and to a lesser degree by modified photosystem II activity (variable fluorescence/maximum fluorescence yield). Although climatic factors may have contributed, these results were most likely attributable to an increase in N deposition southwards. For S. fuscum, photosynthetic rate continued to increase up to a deposition level of 1.49 g N m(-2) year(-1), but for S. balticum it seemed to level out at 1.14 g N m(-2) year(-1). The results for S. balticum suggested that transplants from different origin (with low or intermediate N deposition) respond differently to high N deposition. This indicates that Sphagnum species may be able to adapt or physiologically adjust to high N deposition. Our results also suggest that S. balticum might be more sensitive to N deposition than S. fuscum. Surprisingly, NP(max) was not (S. balticum), or only weakly (S. fuscum) correlated with biomass production, indicating that production is to a great extent is governed by factors other than the photosynthetic capacity.


Chlorophyll fluorescence; Chlorophyll; Carbon dioxide exchange; Photosynthesis; Peatlands

Published in

2009, volume: 159, number: 4, pages: 705-715

Authors' information

Granath, Gustaf
Swedish University of Agricultural Sciences, Department of Ecology
Uppsala University
Breeuwer, Angela
Heijmans, Monique MPD
Berendse, Frank
Rydin, Håkan

UKÄ Subject classification

Environmental Sciences related to Agriculture and Land-use

Publication Identifiers


URI (permanent link to this page)