skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Carbon balance of a boreal bog during a year with an exceptionally dry summer

Journal Article · · Ecology
;  [1];  [2];  [3]; ;  [4]
  1. Univ. of Joensuu (Finland). Dept. of Biology
  2. Univ. of Helsinki (Finland). Dept. of Ecology and Systematics
  3. Finnish Meteorological Inst., Helsinki (Finland)
  4. National Public Health Inst., Kuopio (Finland). Lab. of Environmental Microbiology

Northern peatlands are important terrestrial carbon stores, and they show large spatial and temporal variation in the atmospheric exchange of CO{sub 2} and CH{sub 4}. Thus, annual carbon balance must be studied in detail in order to predict the climatic responses of these ecosystems. Closed-chamber methods were used to study CO{sub 2} and CH{sub 4} in hollow, Sphagnum angustifolium lawn. S. fuscum lawn, and hummock microsites within an ombrotrophic S. fuscum bog. Micrometeorological tower measurements were used as a reference for the CH{sub 3} efflux from the bog. Low precipitation during May--August in 1994 and a warm July--August period caused the water table to drop by more than 15 cm below the peat surface in the hollows and to 48 cm below the surface in high hummocks. Increased annual total respiration exceeded gross production and resulted in a net C loss of 4--157 g/m{sup 2} in the different microsites. Drought probably caused irreversible desiccation in some lawns of S. angustifolium and S. balticum and in S. fuscum in the hummocks, while S. balticum growing in hollows retained its moisture and even increased its photosynthetic capacity during the July--August period. Seasonal (12 May--4 October) CH{sub 4} emissions ranged from 2 g CH{sub 4}-C/m{sup 2} in drier S. fuscum hummocks and lawns to 7 and 14 g/m{sup 2} in wetter S. angustifolium-S. balticum lawns and hollows, respectively.

Sponsoring Organization:
USDOE
OSTI ID:
318773
Journal Information:
Ecology, Vol. 80, Issue 1; Other Information: PBD: Jan 1999
Country of Publication:
United States
Language:
English