Record ID No. |
1973 |
Author(s) |
Jaatinen K., Laiho R., Vuorenmaa A., delCastillo U., Minkkinen K., Pennanen T., Penttila T., Fritze H , 2008 |
Affiliation |
Vantaa Res Unit, Finnish Forest Res Inst, POB 18, Vantaa 01301, FINLAND |
Title |
Responses of aerobic microbial communities and soil respiration to water-level drawdown in a northern boreal fen |
Source. Vol.(no):Page |
Environmental Microbiology.10(2):339-353p. |
Categories |
Mycorrhiza General |
Subjects |
Biochemistry |
Sub-subjects |
Miscellaneous |
Organism |
n.a. |
Country |
FINLAND, Europe |
Abstracts |
On a global basis, peatlands are a major reserve of carbon (C). Hydrological
changes can affect the decomposition processes in peatlands and in turn can alter their C
balance. Since 1959, a groundwater extraction plant has generated a water-level gradient at our
study site that has gradually changed part of the wet fen into a dry peatland forest. The average
water-level drawdown of the gradient (from a pristine 9 cm to 26 cm in the dry end) is close to
an estimate predicted by an increase in mean global temperature of 3 degrees C. We studied the
total microbial community of the aerobic surface peat in four locations along the gradient
through phospholipid fatty acid and PCR-DGGE methods. Additionally, field measurements of soil
respiration showed a threefold increase in the C-emission rate at the driest location compared
with the wettest one, indicating enhanced decomposition. Also, both fungal and bacterial biomass
increased in the drier locations. At the species level, the fungal community changed due to
water-level drawdown whereas actinobacteria were less sensitive to drying. The majority of fungal
sequences were similar to ectomycorrhizal (ECM) fungi, which dominated throughout the gradient.
Our results indicate that ECM fungi might act as important facultative decomposers in
organic-rich environments such as peatlands. |