A5044981299- Peatlands and Wetlands Ecology
- Climate change and permafrost
- Atmospheric and Environmental Gas Dynamics
- Soil Carbon and Nitrogen Dynamics
- Soil and Water Nutrient Dynamics
- Coastal wetland ecosystem dynamics
- Botany and Plant Ecology Studies
- Water Treatment and Disinfection
- Marine and coastal ecosystems
- Methane Hydrates and Related Phenomena
- Cryospheric studies and observations
- Wastewater Treatment and Nitrogen Removal
- Plant Water Relations and Carbon Dynamics
- Bioenergy crop production and management
- Legionella and Acanthamoeba research
- Geology and Paleoclimatology Research
- Microbial Community Ecology and Physiology
- Plant responses to elevated CO2
- Soil and Unsaturated Flow
- Odor and Emission Control Technologies
- Phosphorus and nutrient management
- Constructed Wetlands for Wastewater Treatment
- Atmospheric chemistry and aerosols
- Mycobacterium research and diagnosis
- Geological Studies and Exploration
University of Eastern Finland
2013-2022
Finland University
2011-2020
Public Health Institute
1994-2020
Eastern Finland Laboratory Center
2014
Institute for Molecular Medicine Finland
1990-1997
University of Helsinki
1984-1996
Finnish Institute of Occupational Health
1992
1 Co2 emissions in boreal peatlands were measured during two seasons on various mire site types representing different nutrient statuses and water tables. In order to examine the long term effects of table draw-down CO2 fluxes, sites also included 25-50-year-old drainages. 2 On virgin lowest fluxes at ombrotrophic dominated by Sphagnum fuscum (78-127mg m-2 h-' 12 ?C, 60-200 g CO2-C year') highest with abundant understorey vegetation (183-259mg 290-340g C02-C year-'). 3 Lowering cm increased...
Global wetlands are, at estimate ranging 115–237 Tg CH 4 /yr, the largest single atmospheric source of greenhouse gas methane (CH ). We present a dataset on flux rates totaling 12 measurement years sites from Greenland, Iceland, Scandinavia and Siberia. find that temperature microbial substrate availability (expressed as organic acid concentration in peat water) combined explain almost 100% variations mean annual emissions. The sensitivity emissions shown suggests feedback mechanism climate...
Abstract. Closed (non-steady state) chambers are widely used for quantifying carbon dioxide (CO2) fluxes between soils or low-stature canopies and the atmosphere. It is well recognised that covering a soil vegetation by closed chamber inherently disturbs natural CO2 altering concentration gradients soil, overlying air. Thus, driving factors of not constant during experiment, no linear increase decrease over time within headspace can be expected. Nevertheless, regression has been applied...
Abstract. This article provides an overview of the effects land-use on fluxes carbon dioxide (CO2), methane (CH4) and nitrous oxide (N2O) from peatlands in Nordic countries based field data about 100 studies. In addition, this review aims to identify gaps present knowledge greenhouse gas (GHG) balances associated with these northern ecosystems. Northern have accumulated, as peat, a vast amount atmosphere since last glaciation. However, past climate evidently changed their GHG balance....
Rapidly rising temperatures in the Arctic might cause a greater release of greenhouse gases (GHGs) to atmosphere. To study effect warming on GHG dynamics, we deployed open-top chambers subarctic tundra site Northeast European Russia. We determined carbon dioxide (CO2 ), methane (CH4 and nitrous oxide (N2 O) fluxes as well concentration those gases, inorganic nitrogen (N) dissolved organic (DOC) along soil profile. Studied surfaces ranged from mineral soils vegetated unvegetated areas. As...
As the permafrost region warms, its large organic carbon pool will be increasingly vulnerable to decomposition, combustion, and hydrologic export. Models predict that some portion of this release offset by increased production Arctic boreal biomass; however, lack robust estimates net balance increases risk further overshooting international emissions targets. Precise empirical or model-based assessments critical factors driving are unlikely in near future, so address gap, we present from 98...
Significance Wetlands are unique ecosystems because they in general sinks for carbon dioxide and sources of methane. Their climate footprint therefore depends on the relative sign magnitude land–atmosphere exchange these two major greenhouse gases. This work presents a synthesis simultaneous measurements methane fluxes to assess radiative forcing natural wetlands converted agricultural or forested land. The net impact is strongly dependent whether managed. Here we show that conversion...
Abstract The regional variability in tundra and boreal carbon dioxide (CO 2 ) fluxes can be high, complicating efforts to quantify sink‐source patterns across the entire region. Statistical models are increasingly used predict (i.e., upscale) CO large spatial domains, but reliability of different modeling techniques, each with specifications assumptions, has not been assessed detail. Here, we compile eddy covariance chamber measurements annual growing season gross primary productivity (GPP),...
Permafrost in the Arctic is thawing, exposing large carbon and nitrogen stocks for decomposition. Gaseous release from soils due to permafrost thawing known be substantial, but growing evidence suggests that may also relevant sources of nitrous oxide (N2O). Here we show N2O emissions subarctic peatlands increase as thaws. In our study, highest postthaw occurred bare peat surfaces, a typical landform peatlands, where thaw caused fivefold (0.56 ± 0.11 vs. 2.81 0.6 mg m-2 d-1). These emission...
Despite the fact that heterotrophic nitrification was identified more than 100 years ago, biochemistry of nitrifiers is poorly known and their contribution to in soil still speculative. Heterotrophic need organic compounds as energy source contrast chemolithotrophic nitrifiers. Most potential pathways for nitrite/nitrate production by heterotrophs can be considered secondary metabolism. Only simultaneous denitrification some bacteria have connection Evidently, fungi differ. Some oxidizing...
Greenhouse gas fluxes (CH4, N20 and C02) at a managed Finnish peat soil site were compared with those in virgin fen 1991 1992. The field was drained about 60 years ago, as it used for pasturing fodder production, the CH4 released by cattle estimated on basis of data literature. annual budgets gases their GWP values calculated to assess climatic impact current agricultural activity. Methane emission from site, 1 kg CH4-C ha- yr- 1, low, that natural 260 1. Annual 8 9 N20-N ha - yr 1992,...
Northern peatlands are important terrestrial carbon stores, and they show large spatial temporal variation in the atmospheric exchange of CO2 CH4. Thus, annual balance must be studied detail order to predict climatic responses these ecosystems. Closed-chamber methods were used study CH4 hollow, Sphagnum angustifolium lawn, S. fuscum hummock microsites within an ombrotrophic bog. Micrometeorological tower measurements as a reference for efflux from Low precipitation during May–August 1994 (84...
Methane (CH 4 ) fluxes were measured at 17 peatland sites with different nutritional and hydrological characteristics in the southern middle boreal zones Finland by a static chamber technique. Many of natural peatlands also had counterparts drained for forestry 30–50 years ago. The mean emissions from May to September 8.0 g CH m −2 ombrogenous bogs 19.0 minerogenous fens thus being higher than 2 yr −1 estimated Canadian peatlands. Change water table level greater effect on bogs. 3.9 0.3 ,...
Abstract We show that sediment respiration is one of the key factors contributing to high CO 2 supersaturation in and evasion from Finnish lakes, evidently also over large areas boreal landscape, where majority lakes are small shallow. A subpopulation 177 randomly selected (<100 km ) 32 with highest total phosphorus (P tot concentrations Nordic Lake Survey (NLS) data base were sampled during four seasons at depths. Patterns plotted against depth time demonstrate strong accumulation...
Abstract A tropical ombrotrophic peatland ecosystem is one of the largest terrestrial carbon stores. Flux rates dioxide (CO 2 ) and methane (CH 4 were studied at various peat water table depths in a mixed‐type swamp forest floor Central Kalimantan, Indonesia. Temporary gas fluxes on microtopographically differing hummock hollow surfaces combined with data to produce annual cumulative flux estimates. Hummocks formed mainly from living dead tree roots decaying debris maintained relatively...
The availability of organic carbon is considered the key factor to regulate microbial regrowth in drinking water network. However, boreal regions (northern Europe, Russia, and North America) contain a large amount forests peatlands. Therefore, natural waters (lakes, rivers, groundwater) northern hemisphere generally have high content carbon. We found that growth Finland highly regulated not only by but also phosphorus. Microbial increased up phosphate concentration 10 micrograms PO4-P...
Abstract. This study explores the variability in concentrations of dissolved CH4 and annual flux estimates pelagic zone a statistically defined sample 207 lakes Finland. The were situated boreal zone, an area where mean air temperature ranges from −2.8 to 5.9°C. We examined how lake dynamics related regional types assessed according EU water framework directive. Ten on basis chemistry, color, size. Lakes sampled for four times per year, at different depths deepest point each lake. found that...