Changes in microbial community structure and function following Sphagnum peatland restoration

This study examines the recovery of the microbial compartment following active restoration of a North American ombrotrophic peatland extracted for horticultural peat-based substrates and restored by the Sphagnum moss transfer method. We used phospholipid fatty acids (PLFAs) to portrait the microbial community structure and Community Level Physiological Profiles (CLPP) to describe the functional diversity of the microbial communities. Our results indicate that the PLFA profiles were different between the beginning and the end of the growing season, but that it was impossible to distinguish five different vegetation classes found along the disturbance-recovery gradient on the basis of the microbial community structure. The pH, the cover of mosses, Ledum groenlandicum and Eriophorum vaginatum var. spissum were the best environmental predictors for the PLFA composition. The newly formed peat found in aerobic conditions beneath restored Sphagnum carpets had the highest decomposition capacity, whereas the lowest rates were found in the surface samples of non-restored conditions or in the deepest horizons of the natural samples. A large proportion of the variation in the physiological profiles was explained with variables related to the vegetation cover, the physicochemical environment and the microbial structure of the community, which is very promising for future monitoring studies. Overall, this study demonstrates that the recovery of particular plant groups, namely mosses and shrubs in restored peatlands might be the driver of changes occurring in the structure of the microbial communities in restored peatlands.     

Using Thermal Sensitivity Analysis to Determine the Impact of Drainage on the Hydrochemistry of a Tropical Peat Soil from Malaysia

Peat from an area of pristine swamp in Malaysia and from an area of that swamp drained 10 years earlier for agriculture was incubated along a temperature gradient from 0 to 20 °C to simulate microbial activity through changes in temperature. With increasing temperature, nitrate availability decreased in the pristine peat but increased in the drained peat, suggesting that drainage has altered the principle nitrate transformation process from denitrification to nitrification. Sulfate concentrations in the pristine peat exhibited a greater proportional decrease with increasing temperature than in the drained peat, suggesting that drainage has decreased the influence of sulfate reduction over sulfate availability at this site. With the exception of phosphate, nutrient concentrations in the drained site were significantly greater (P < 0.05) than in the pristine site. Biogeochemical models should consider that drained peatlands may respond very differently to the temperature change predicted by current climate change models.     

Strong functional stability of soil microbial communities under semiarid Mediterranean conditions and subjected to long-term shifts in baseline precipitation

We investigated the effect of soil microclimate on the structure and functioning of soil microbial communities in a Mediterranean Holm-oak forest subjected to 10 years of partial rain exclusion manipulations, simulating average drought conditions expected in Mediterranean areas for the following decades. We applied a high throughput DNA pyrosequencing technique coupled to parallel measurements of microbial respiration (R_H) and temperature sensitivity of microbial respiration (Q₁₀). Some consistent changes in the structure of bacterial communities suggest a slow process of community shifts parallel to the trend towards oligotrophy in response to long-term droughts. However, the structure of bacterial communities was mainly determined by short-term environmental fluctuations associated with sampling date (winter, spring and summer) rather than long-term (10 years) shifts in baseline precipitation. Moreover, long-term drought did not exert any chronic effect on the functioning of soil microbial communities (R_H and Q₁₀), emphasizing the functional stability of these communities to this long-term but mild shifts in water availability. We hypothesize that the particular conditions of the Mediterranean climate with strong seasonal shifts in both temperature and soil water availability but also characterized by very extreme environmental conditions during summer, was acting as a strong force in community assembling, selecting phenotypes adapted to the semiarid conditions characterizing Mediterranean ecosystems. Relations of climate with the phylogenetic structure and overall diversity of the communities as well as the distribution of the individual responses of different lineages (genera) to climate confirmed our hypotheses, evidencing communities dominated by thermotolerant and drought-tolerant phenotypes.     

Scots pine litter decomposition along drainage succession and soil nutrient gradients in peatland forests, and the effects of inter-annual weather variation

Peatlands form a large carbon (C) pool but their C sink is labile and susceptible to changes in climate and land-use. Some pristine peatlands are forested, and others have the potential: the amount of arboreal vegetation is likely to increase if soil water levels are lowered as a consequence of climate change. On those sites tree litter dynamics may be crucial for the C balance. We studied the decomposition of Scots pine (Pinus sylvestris L.) needle and root litter in boreal peatland sites representing gradients in drainage succession (succession following water level drawdown caused by forest drainage) and soil nutrient level during several years of varying weather conditions. Neither gradient had an unambiguous effect on litter mass loss. Mass loss over 2 years was faster in undrained versus drained sites for both needle litter, incubated in the moss layer, and fine root litter, incubated in 0-10 cm peat layer, suggesting moisture stress in the surface layers of the drained sites limited decomposition. Differences among the drained sites were not consistent. Among years, mass loss correlated positively with precipitation variables, and mostly negatively or not at all with temperature sum. We concluded that a long-term water level drawdown in peatlands does not necessarily enhance decay of fresh organic matter. Instead, the drained site may turn into a ‘large hummock-system’ where several factors, including litter quality, relative moisture deficiency, higher acidity, lower substrate temperature, and in deeper layers also oxygen deficiency, may interact to constrain organic matter decomposition. Further, the decomposition rates may not vary systematically among sites of different soil nutrient levels following water level drawdown. Our results emphasize the importance of annual weather variations on decomposition rates, and demonstrate that single-period incubation studies incorporate an indeterminable amount of temporal variation.     

Abiotic drivers and their interactive effect on the flux and carbon isotope (14C and δ13C) composition of peat-respired CO2

Feedbacks to global warming may cause terrestrial ecosystems to add to anthropogenic CO₂ emissions, thus exacerbating climate change. The contribution that soil respiration makes to these terrestrial emissions, particularly from carbon-rich soils such as peatlands, is of significant importance and its response to changing climatic conditions is of considerable debate. We collected intact soil cores from an upland blanket bog situated within the northern Pennines, England, UK and investigated the individual and interactive effects of three primary controls on soil organic matter decomposition: (i) temperature (5, 10 and 15 °C); (ii) moisture (50 and 100% field capacity – FC); and (iii) substrate quality, using increasing depth from the surface (0–10, 10–20 and 20–30 cm) as an analogue for increased recalcitrance of soil organic material. Statistical analysis of the results showed that temperature, moisture and substrate quality all significantly affected rates of peat decomposition. Q₁₀ values indicated that the temperature sensitivity of older/more recalcitrant soil organic matter significantly increased (relative to more labile peat) under reduced soil moisture (50% FC) conditions, but not under 100% FC, suggesting that soil microorganisms decomposing the more recalcitrant soil material preferred more aerated conditions. Radiocarbon analyses revealed that soil decomposers were able to respire older, more recalcitrant soil organic matter and that the source of the material (deduced from the δ¹³C analyses) subject to decomposition, changed depending on depth in the peat profile.     

Dung application increases CH<Subscript>4</Subscript> production potential and alters the composition and abundance of methanogen community in restored peatland soils from Europe

Peatland restoration via rewetting aims to recover biological communities and biogeochemical processes typical to pristine peatlands. While rewetting promotes recovery of C accumulation favorable for climate mitigation, it also promotes methane (CH₄) emissions. The potential for exceptionally high emissions after rewetting has been measured for Central European peatland sites previously grazed by cattle. We addressed the hypothesis that these exceptionally high CH₄ emissions result from the previous land use. We analyzed the effects of cattle dung application to peat soils in a short- (2 weeks), a medium- (1 year) and a long-term (grazing) approach. We measured the CH₄ production potentials, determined the numbers of methanogens by mcrA qPCR, and analyzed the methanogen community by mcrA T-RFLP-cloning-sequencing. Dung application significantly increased the CH₄ production potential in the short- and the medium-term approach and non-significantly at the cattle-grazed site. The number of methanogens correlated with the CH₄ production in the short- and the long-term approach. At all three time horizons, we found a shift in methanogen community due to dung application and a transfer of rumen methanogen sequences (Methanobrevibacter spp.) to the peatland soil that seemed related to increased CH₄ production potential. Our findings indicate that cattle grazing of drained peatlands changes their methanogenic microbial community, may introduce rumen-associated methanogens and leads to increased CH₄ production. Consequently, rewetting of previously cattle-grazed peatlands has the potential to lead to increased CH₄ emissions. Careful consideration of land use history is crucial for successful climate mitigation with peatland rewetting.     

Sheep excreta cause no positive priming of peat-derived CO2 and N2O emissions

Large areas of peatlands in Germany and the Netherlands are affected by drainage and high nitrogen deposition. Sheep grazing is a common extensive management activity on drained peatlands, in particular on nature protection areas. However, input of easily mineralisable material such as sheep excrements could enhance degradation of soil organic carbon (C_org), thereby increasing the effect of these ecosystems on national GHG budgets. Thus, a microcosm experiment on the influence of sheep excreta on GHG emissions from a histic Gleysol with strongly degraded peat was set up. The ¹⁵N and ¹³C stable isotope tracer technique was used to partition sources of CO₂ and N₂O. Labeled sheep faeces and urine were obtained by feeding enriched material. Undisturbed soil columns were treated with surface application of urine, faeces or mixtures of both in different label combinations to distinguish between direct effects and possible priming effects. Incubation was done under stable temperature and precipitation conditions. Fluxes as well as ¹⁵N and ¹³C enrichment of N₂O and CO₂, respectively, were measured for three weeks. Addition of sheep excreta increased emission of total CO₂ in proportion to the added carbon amounts. There was no CO₂ priming in the peat. No effect on CH₄ and N₂O was observed under the aerobic experimental conditions. The N₂O–N source shifted from peat to excreta, which indicates negative priming, but priming was not significant. The results indicate that sheep excreta do not significantly increase GHG emissions from degraded peat soils. Considering the degraded peatland preserving benefits, sheep grazing on peatlands affected by drainage and high nitrogen deposition should be further promoted.     

No signs of thermal acclimation of heterotrophic respiration from peat soils exposed to different water levels

In a mesocosm experiment, with bare peat soils exposed to different water levels (WL), we examined whether heterotrophic respiration (R_h) acclimated to a 3 ^°C temperature increase. Across all WLs, R_h at 15 ^°C was never lower in the heated treatment than in the unheated treatment, indicating that R_h did not acclimate to the warmer conditions. We hypothesize that this lack of thermal acclimation is due to the unlimited substrate availability in these organic soils. These results imply that peat soils may exhibit a sustained positive feedback to global warming.     

增温与干旱双重变化对若尔盖泥炭CH4排放的影响

若尔盖泥炭地经历了长期人为排水,未来又面临着强烈的变暖干旱,会对泥炭地CH₄排放产生复杂影响。在若尔盖选取了近自然和长期人为排水两种泥炭地类型,采集1 m深泥炭柱,采用室内环境控制试验,设定不同的氧气、水分和温度条件,探索这两种典型泥炭地的泥炭CH₄排放对增温与干旱双重变化的响应差异。结果表明:(1)由于水位降低和泥炭有机物质量下降,长期排水泥炭地的中下层泥炭(20—80 cm)CH₄累积排放量显著低于近自然泥炭地。(2)两种泥炭地的表层和深层泥炭CH₄排放都对升温不敏感,而中下层泥炭的CH₄累积排放量从5℃到15℃显著增加。(3)模拟增温10℃同时干旱水位降低20 cm条件下,中层泥炭受到了温度、水分和氧气变化的叠加影响,CH₄排放变化最剧烈。(4)最终整个1 m深泥炭近自然泥炭地高温低水位的CH₄总排放量为(204.29±15.13)μg/gC,比其低温高水位显著升高66.43 μg/gC(约48%); 排水泥炭地高温低水位的CH₄总排放量为(75.64±9.41)μg/gC,比其低温高水位升高11.95 μg/gC(约19%)。综上,升温干旱气候会对若尔盖泥炭地的有机碳稳定性造成破坏性影响,会集中导致中层泥炭CH₄排放的剧烈变化,可能最终使本区域CH₄排放量显著提高。     

Influence of hydrological fluxes on the structure of nitrate-reducing bacteria communities in a peatland

Factors influencing nitrate dynamics and nitrate-reducing bacteria in peat soil in the field, were investigated in laboratory experiments. A previous study had indicated that the on-site effects of redox conditions and nutrient fluxes on microbial activity were influenced by hydrological conditions. However, the laboratory experiments indicated that peat samples from sites under different hydrological regimes exhibited different microbial activities independently of oxygenation conditions. The effects of redox conditions and nutrient fluxes (i.e. influence of NO₃⁻ and O₂ concentration) on the nitrate reducer community were therefore assessed. Microbial community structures in peat samples from sites under different hydrologic regimes were compared using Terminal-Restriction Fragment Length Polymorphism diversity signatures of the narG gene. This gene encodes the catalytic subunit of the nitrate reductase. Unexpectedly, the nitrate reducer communities were very similar at the beginning of the experiment whatever the peatland soil analysed. However, a strong structuration and divergence within the nitrate reducer communities, that was site-dependent, was evident after 76 h of incubation. These modifications within the microbial communities seemed to be due to differences in peat saturation at the sampling sites resulting from the different hydrological regimes. Of the forcing variables tested, oxygenation had a slight effect on the composition of the nitrate-reducers' community whereas nitrate addition had no effect. This study shows that a physical constraint such as hydrological regime might be considered important in microbial community composition.     

Responses of soil respiration and its components to drought stress

Purpose

Climate change is likely to increase both intensity and frequency of drought stress. The responses of soil respiration (R _s) and its components (root respiration, R _r; mycorrhizal respiration, R _m; and heterotrophic respiration, R _h) to drought stress can be different. This work aims to review the recent and current literature about the variations in R _s during the period of drought stress, to explore potential coupling processes and mechanisms between R _s and driving factors in the context of global climate change.

Results and discussion

The sensitivity of soil respiration and its components to drought stress depended on the ecosystems and seasonality. Drought stress depressed R _s in mesic and xeric ecosystems, while it stimulated R _s in hydric ecosystems. The reductions in supply and availability of substrate decreased both auto- and heterotrophic respirations, leading to the temporal decoupling of root and mycorrhizal respiration from canopy photosynthesis as well as C allocation. Drought stress also reduced the diffusion of soluble C substrate, and activities of extracellular enzymes, consequently, limited microbial activity and reduced soil organic matter decomposition. Drought stress altered Q ₁₀ values and broke the coupling between temperature and soil respiration. Under drought stress conditions, R _m is generally less sensitive to temperature than R _r and R _h. Elevated CO₂ concentration alleviated the negative effect of drought stress on soil respiration, principally due to the promotion of plant C assimilation subsequently, which increased substrate supply for respiration in both roots and soil microorganisms. Additionally, rewetting stimulated soil respiration dramatically in most cases, except for soil that experienced extreme drought stress periods. The legacy of drought stress can also regulate the response of soil respiration rate to rewetting events in terrestrial ecosystems through changing abiotic drivers and microbial community structure.

Conclusions and perspectives

There is increasing evidence that drought stress can result in the decoupling of the above- and belowground processes, which are associated with soil respiration. However, studies on the variation in rates of soil respiration and its components under different intensities and frequencies of drought stress over the ecosystems should be reinforced. Meanwhile, molecular phylogenetics and functional genomics should be applied to link microbial ecology to the process of R _s. In addition, we should quantify the relationship between soil respiration and global change parameters (such as warming and elevated [CO₂]) under drought stress. Models simulating the rates of soil respiration and its components under global climate change and drought stress should also be developed.     

Substrate utilisation profiles of microbial communities in peat are depth dependent and correlate with whole soil FTIR profiles

A multiple substrate induced respiration (SIR) assay, using ¹⁴C-labelled carbon sources, was used to evaluate community level physiological profiles (CLPP) of the microbial community in peat horizons of differing degrees of humification. The separation and grouping of the peat horizons by CLPP was similar to the pattern produced by analysis of the organic carbon chemistry of the peat horizons by Fourier Transform Infrared (FTIR) spectroscopy and therefore reflected the level of decomposition. Partial redundancy analysis showed that a large proportion (68.7%) of the variability in the CLPP data could be attributed to the ratio of polysaccharide to ‘carboxylate’ FTIR bands alone. The multiple substrate SIR technique may, therefore, be a powerful technique to further elucidate the influence of the microbial constituent of peat on the potential activity and patterns of cycling of labile carbon in peatlands.     

Evaluation of phosphorus mobilization potential in rewetted fens by an improved sequential chemical extraction procedure

After rewetting of peatlands, phosphorus (P) pore‐water concentrations were up to three orders of magnitude greater than under pristine conditions. It was hypothesized that different mobilization processes such as ion‐exchange reactions, biotic/abiotic redox reactions, acidification and ongoing anaerobic decomposition of particulate organic matter by hydrolytic cleavage and fermentation might be responsible. To identify P pools in peat samples of varying degrees of decomposition, we modified and improved a sequential chemical extraction method that allowed conclusions on potential mobilization mechanisms in rewetted peatlands. The results indicated that the earlier drainage of rewetted fens strongly increased the P mobilization potential in the upper decomposed peat layers. Accordingly, the amount of P bound to redox‐sensitive (bicarbonate/dithionite soluble) compounds (BD‐P) was, on average, one order of magnitude greater in decomposed peat of rewetted fens (5.4–14.3 μmol P g^?1 dry matter or DM) than in underlying less‐decomposed peat layers (0.2–1.9 μmol P g^?1 DM) or slightly decomposed peat derived from pristine fens (0.4–2.0 μmol P g^?1 DM). The BD‐P fraction found in the upper very decomposed peat layers appears to be most important for P mobilization in rewetted fens and accounted for 85% of the variability of P mobilization rates. Despite uncertainties regarding P diagenetic processes in peat, as well as the development of microbial decomposition processes, in the long‐term, high pore‐water P concentrations can be expected in rewetted fens for decades to come.     

Application of wood ash accelerates soil respiration and tree growth on drained peatland

Forested peatlands contain large pools of terrestrial carbon. As well as drainage, forest management such as fertilizer application can affect these pools. We studied the effect of wood ash (application rates 0, 5 and 15 t ha^?1) on the heterotrophic soil respiration (CO₂ efflux), cellulose decomposition, soil nutrients, biomass production and amount of C accumulated in a tree stand on a pine‐dominated drained mire in central Finland. The ash was spread 13 years before the respiration measurements. The annual CO₂ efflux was statistically modelled using soil temperature as the driving variable. Wood ash application increased the amounts of mineral nutrients of peat substantially and increased soil pH in the uppermost 10 cm layer by 1.5–2 pH units. In the surface peat, the decomposition rate of cellulose in the ash plots was roughly double that in control plots. Annual CO₂ efflux was least on the unfertilized site, 238 g CO₂‐C m^?2 year^?1. The use of wood ash nearly doubled CO₂ efflux to 420–475 g CO₂‐Cm^?2 year^?1 on plots fertilized with 5–15 t ha^?1 of ash, respectively. Furthermore, ash treatments resulted also in increased stand growth, and during the measurement year, the growing stand on ash plots accumulated carbon 11–12 times faster than the control plot. The difference between peat C emission and amount of C sequestered by trees on the ash plots was 43–58 g C m^?2, while on the control plot it was 204 g C m^?2. Our conclusion is that adding wood ash as a fertilizer increases more C sequestration in the tree stand than C efflux from the peat.     

Abiotic drivers and their interactive effect on the flux and carbon isotope (C and δC) composition of peat-respired CO2

Feedbacks to global warming may cause terrestrial ecosystems to add to anthropogenic CO₂ emissions, thus exacerbating climate change. The contribution that soil respiration makes to these terrestrial emissions, particularly from carbon-rich soils such as peatlands, is of significant importance and its response to changing climatic conditions is of considerable debate. We collected intact soil cores from an upland blanket bog situated within the northern Pennines, England, UK and investigated the individual and interactive effects of three primary controls on soil organic matter decomposition: (i) temperature (5, 10 and 15 °C); (ii) moisture (50 and 100% field capacity – FC); and (iii) substrate quality, using increasing depth from the surface (0–10, 10–20 and 20–30 cm) as an analogue for increased recalcitrance of soil organic material. Statistical analysis of the results showed that temperature, moisture and substrate quality all significantly affected rates of peat decomposition. Q₁₀ values indicated that the temperature sensitivity of older/more recalcitrant soil organic matter significantly increased (relative to more labile peat) under reduced soil moisture (50% FC) conditions, but not under 100% FC, suggesting that soil microorganisms decomposing the more recalcitrant soil material preferred more aerated conditions. Radiocarbon analyses revealed that soil decomposers were able to respire older, more recalcitrant soil organic matter and that the source of the material (deduced from the δ¹³C analyses) subject to decomposition, changed depending on depth in the peat profile.     

Factors causing temporal and spatial variation in heterotrophic and rhizospheric components of soil respiration in afforested organic soil croplands in Finland

Partitioning soil respiration (SR) into its components, heterotrophic and rhizospheric respiration, is an important step for understanding and modelling carbon (C) cycling in organic soils. However, no partitioning studies on afforested organic soil croplands exist. We separated soil respiration originating from the decomposition of peat (SR_P), and aboveground litter (SR_L) and root respiration (SR_R) in six afforested organic soil croplands in Finland with varying tree species and stand ages using the trenching method. Across the sites temporal variation in SR was primarily related to changes in soil surface temperature (?5 cm), which explained 71–96% of variation in SR rates. Decomposition of peat and litter was not related to changes in water table level, whereas a minor increase in root respiration was observed with the increase in water table depth. Temperature sensitivity of SR varied between the different respiration components: SR_P was less sensitive to changes in soil surface temperature than SR_L or SR_R. Factors explaining spatial variation in SR differed between different respiration components. Annual SR_P correlated positively with peat ash content while that of SR_L was found to correlate positively with the amount of litter on the forest floor, separately for each tree species. Root respiration correlated positively with the biomass of ground vegetation. From the total soil respiration peat decomposition comprised a major share of 42%; the proportion of autotrophic respiration being 41% and aboveground litter 17%. Afforestation lowered peat decomposition rates. Nevertheless the effect of agricultural history can be seen in peat properties for decades and due to high peat decomposition rates these soils still loose carbon to the atmosphere.     

Carbon loss in drained forestry peatlands in Finland,estimated by re‐sampling peatlands surveyed in the 1980s

The total area of boreal peatlands is about 3.5 million km² and they are estimated to contain 15–30% of the global soil carbon (C) storage. In Finland, about 60 000 km², or 60% of the original peatland area, has been drained, mainly for forestry improvement. We have studied C inventory changes on forestry‐drained peatlands by re‐sampling the peat stratum in 2009 at the precise locations of quantitative peat mass analyses conducted as part of peatland transect surveys during the 1980s. The old and new profiles were correlated mainly by their ignition residue stratigraphies; at each site we determined a reference level, identifiable in both profiles, and calculated the cumulative dry mass and C inventories above it. Comparison of a total of 37 locations revealed broad variation, from slight increase to marked decrease; on average the 2009 results indicate a loss of 7.4 (SE ± 2.5) kg m^?2 dry peat mass when compared with the 1980s values. Expressed on an annual basis, the results indicate an average net loss of 150 g C m^?2 year^?1 from the soil of drained forestry peatlands in the central parts of Finland. The C balance appeared not to correlate with site fertility (fertility classes according to original vegetation type), nor with post‐drainage timber growth.     

Acid Mine Drainage Treatment Assisted by Lignite-Derived Humic Substances

Rewetting of agriculturally used peatlands has been proposed as a measure to stop soil subsidence, conserve peat and rehabilitate ecosystem functioning. Unintended consequences might involve nutrient release and changes in the greenhouse gas (GHG) balance towards CH₄-dominated emission. To investigate the risks and benefits of rewetting, we subjected soil columns from drained peat- and clay-covered peatlands to different water level treatments: permanently low, permanently inundated and fluctuating (first inundated, then drained). Surface water and soil pore water chemistry, soil-extractable nutrients and greenhouse gas fluxes were measured throughout the experiment. Permanent inundation released large amounts of nutrients into pore water, especially phosphorus (up to 11.7 mg P-PO₄ l^?1) and ammonium (4.8 mg N-NH₄ l^?1). Phosphorus release was larger in peat than in clay soil, presumably due to the larger pool of iron-bound phosphorus in peat. Furthermore, substantial amounts of phosphorus and potassium were exported from the soil matrix to the surface water, risking the pollution of local species-rich (semi-)aquatic ecosystems. Rewetting of both clay and peat soil reduced CO₂ emissions. CH₄ emissions increased, but, in contrast to the expectations, the fluxes were relatively low. Calculations showed that rewetting reduced net cumulative GHG emissions expressed as CO₂ equivalents.     

Decomposition of organic matter in peat soil in a minerotrophic mire

Decomposition of organic materials, oxygen consumption, and carbon dioxide emission were investigated in Masukata mire, a small minerotrophic mire in central Japan. We selected three dominant community types in the mire, a Sphagnum palustre community, a Phragmites australis community, and an Alnus japonica community, for the decomposition study sites. Decomposition rates were measured in the field by examining mass loss of peat and cellulose for 6 months. The oxygen consumption rate was measured in the field using a closed chamber equipped with an oxygen electrode. The carbon dioxide emission rate of the peat was measured by an infrared gas analyser in the laboratory under controlled conditions. Results of these measurements were tested by correlation analysis. The rate of mass loss of peat positively correlated with the CO₂ emission rate. The cellulose decomposition rate showed significant differences among community types, and it had significant positive correlation with the oxygen consumption rate. Although oxygen consumption measurement is not generally used to estimate peatland soil respiration, the oxygen consumption method can be used for predicting long-term decomposition rate according to different vegetation types within a short time.