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View article: The importance of continuous comprehensive Integrated observations: from feedback loop analysis to CarbonSink+
The importance of continuous comprehensive Integrated observations: from feedback loop analysis to CarbonSink+ Open
The Earth is facing several environmental challenges on a global scale, often called “Grand Challenges” (https://www.wcrp-climate.org/grand-challenges/). The growing population (https://pdp.unfpa.org) needs fresh air, fresh water, food and…
View article: Measuring shoot-level NOx flux in field conditions: the role of blank chambers
Measuring shoot-level NOx flux in field conditions: the role of blank chambers Open
We monitored NOx fluxes in an empty chamber and in chambers containing Scots pine shoots. Our aims were to observe how the chamber blank behaves in non-controlled field conditions and at low ambient NOx concentrations, to find ways of redu…
View article: A comprehensive network of measuring stations to monitor climate change
A comprehensive network of measuring stations to monitor climate change Open
The atmospheric CO2 concentration and temperature have been rather stable at the time scale of millennia, although rather large variations have occurred during longer periods. The extensive use of fossil fuels and destruction of forests ha…
View article: Ozone flux measurements over a Scots pine forest using eddy covariance method: performance evaluation and comparison with flux-profile method
Ozone flux measurements over a Scots pine forest using eddy covariance method: performance evaluation and comparison with flux-profile method Open
Ozone fluxes were measured over a forest in southern Finland between August 2001 and July 2002 using the eddy covariance method. Systematic errors due to the imperfect frequency response of the instrumentation and random errors due to the …
View article: Changes in nitrogen content and isotopic composition in subarctic Empetrum nigrum seeds in the period 1976–2010
Changes in nitrogen content and isotopic composition in subarctic Empetrum nigrum seeds in the period 1976–2010 Open
1) Dating Laboratory, FMNH, FI-00014 University of Helsinki, Finland 2) Natural Environment Centre, Finnish Environment Institute, FI-00251 Helsinki, Finland (corresponding author’s e-mail: [email protected]) 3) Department of Fo…
View article: Patterns in airborne pollen and other primary biological aerosol particles (PBAP), and their contribution to aerosol mass and number in a boreal forest
Patterns in airborne pollen and other primary biological aerosol particles (PBAP), and their contribution to aerosol mass and number in a boreal forest Open
We studied variation in concentrations of airborne pollen and other particles of biological origin in a boreal forest in Finland during 2003–2004. The highest concentrations of pollen were observed in late spring and early summer, whereas …
View article: Eddy covariance measurements of CO2 and sensible and latent heat fluxes during a full year in a boreal pine forest trunk-space
Eddy covariance measurements of CO2 and sensible and latent heat fluxes during a full year in a boreal pine forest trunk-space Open
The eddy covariance method was used to determine turbulent heat fluxes and CO2 flux below a boreal Scots pine canopy 3 m above the forest floor. Data were filtered using standard deviation of the vertical velocity as a measure of the turbu…
View article: CO2-induced terrestrial climate feedback mechanism : From carbon sink to aerosol source and back
CO2-induced terrestrial climate feedback mechanism : From carbon sink to aerosol source and back Open
Feedbacks mechanisms are essential components of our climate system, as they either increase or decrease changes in climate-related quantities in the presence of external forcings. In this work, we provide the first quantitative estimate r…
View article: Finnish Centre of Excellence in Physics, Chemistry, Biology and Meteorology of Atmospheric Composition and Climate Change : summary and outlook
Finnish Centre of Excellence in Physics, Chemistry, Biology and Meteorology of Atmospheric Composition and Climate Change : summary and outlook Open
markku Kulmala1)*, hanna K. lappalainen1)2), Jaana Back1)3), ari laaksonen2)4), eero nikinmaa3), marja-liisa riekkola5), timo vesala1), Yrjo viisanen2), tuula aalto2), michael Boy1), miikka Dal maso6), mikael ehn1), hannele hakola2), Pertt…
View article: Smart-SMEAR : on-line data exploration and visualization tool for SMEAR stations
Smart-SMEAR : on-line data exploration and visualization tool for SMEAR stations Open
View article: Wintertime CO2 evolution from a boreal forest ecosystem
Wintertime CO2 evolution from a boreal forest ecosystem Open
We investigated wintertime ecosystem activity and CO2 efflux over three winters (1 November–28 February 1997–2000) in a boreal Scots pine stand in Finland. During the three winters the cumulative wintertime CO2 efflux measured with continu…
View article: The effect of temperature and PAR on the annual photosynthetic production of Scots pine in northern Finland during 1906–2002
The effect of temperature and PAR on the annual photosynthetic production of Scots pine in northern Finland during 1906–2002 Open
The annual photosynthetic production of Scots pine (Pinus sylvestris) was simulated for 1906-2002 for a location in northern Finland. We used the PhenPhoto model, which combines two key features of photosynthesis: the response to instantan…
View article: Accurate measurements of CO2 mole fraction in the atmospheric surface layer by an affordable instrumentation
Accurate measurements of CO2 mole fraction in the atmospheric surface layer by an affordable instrumentation Open
We aimed to assess the feasibility of an affordable instrumentation, based on a non-dispersive infrared analyser, to obtain atmospheric CO2 mole fraction data for background CO2 measurements from a flux tower site in southern Finland. The …
View article: On-line field measurements of monoterpene emissions from Scots pine by proton-transfer-reaction mass spectrometry
On-line field measurements of monoterpene emissions from Scots pine by proton-transfer-reaction mass spectrometry Open
We measured the daily patterns of monoterpene emissions from Scots pine (Pinus sylvestris) trees in a boreal coniferous forest in August and September 2004, using an on-line chamber method combined with a proton-transfer-reaction mass spec…
View article: Biogenic aerosol formation in the boreal forest
Biogenic aerosol formation in the boreal forest Open
Aerosol formation and subsequent particle growth in the ambient air have been frequently observed at the boreal forest site (SMEAR II station), southern Finland. The EU funded project BIOFOR (Biogenic aerosol formation in the boreal forest…
View article: Temporal variations in surface water CO2 concentration in a boreal humic lake based on high-frequency measurements
Temporal variations in surface water CO2 concentration in a boreal humic lake based on high-frequency measurements Open
We measured surface water CO 2 concentrations continuously at three different depths to reveal the seasonal, daily and diel CO 2 dynamics of a steeply stratified pristine, spring-meromictic, humic lake during April 2005-October 2006. The…
View article: Predicting boreal conifer photosynthesis in field conditions
Predicting boreal conifer photosynthesis in field conditions Open
Automatic continuous monitoring of shoot-level gas exchange and environmental factors in natural conditions provides an efficient but unexploited tool for testing the predictive power of plant photosynthesis models. We used automatically o…
View article: CO2 exchange and component CO2 fluxes of a boreal Scots pine forest
CO2 exchange and component CO2 fluxes of a boreal Scots pine forest Open
View article: Towards quantitative ecology : Newton’s principia revisited
Towards quantitative ecology : Newton’s principia revisited Open
View article: Water balance of a boreal Scots pine forest
Water balance of a boreal Scots pine forest Open
In terrestrial ecosystems, the amount and availability of water is one of the key factors affecting the net primary productivity and other biological processes of the system. At the SMEAR-II station, we have monitored the water balance of …
View article: Estimation of different forest-related contributions to the radiative balance using observations in southern Finland
Estimation of different forest-related contributions to the radiative balance using observations in southern Finland Open
The effect of boreal forest on the Earth's energy budget was estimated in field conditions in Hyytiälä, southern Finland. The indirect aerosol effect due to new particle formation, the effect of forest carbon sequestration and the effect o…
View article: Spring recovery of photosynthesis and atmospheric particle formation
Spring recovery of photosynthesis and atmospheric particle formation Open
View article: Pressure responses of portable CO2 concentration sensors
Pressure responses of portable CO2 concentration sensors Open
View article: Investigating high-resolution stable isotope signals of annual tree rings across a moisture gradient with the MuSICA model
Investigating high-resolution stable isotope signals of annual tree rings across a moisture gradient with the MuSICA model Open
International audience
View article: SMEAR data preservation 2019
SMEAR data preservation 2019 Open
This data publication was done for preservation of SMEAR data. It links together 12 published datasets that contain continuous long-term environmental measurements under different themes or fields of science (meteorology, soil, air chemist…
View article: Prediction of photosynthesis in Scots pine ecosystems across Europe by a needle-level theory
Prediction of photosynthesis in Scots pine ecosystems across Europe by a needle-level theory Open
Photosynthesis provides carbon for the synthesis of macromolecules to construct cells during growth. This is the basis for the key role of photosynthesis in the carbon dynamics of ecosystems and in the biogenic CO2 assimilation. The develo…
View article: High-frequency productivity estimates for a lake from free-water CO <sub>2</sub> concentration measurements
High-frequency productivity estimates for a lake from free-water CO <sub>2</sub> concentration measurements Open
Lakes are important actors in biogeochemical cycles and a powerful natural source of CO2. However, they are not yet fully integrated in carbon global budgets, and the carbon cycle in the water is still poorly understood. In freshwater ecos…
View article: High-frequency productivity estimates for a lake from free-waterCO <sub>2</sub> concentration measurements
High-frequency productivity estimates for a lake from free-waterCO <sub>2</sub> concentration measurements Open
Lakes are important actors in biogeochemical cycles and a powerful natural source of CO2. However, they are not yet fully integrated in carbon budgets, and the carbon cycle in the water is still poorly understood. In freshwater ecosystems,…
View article: Supplementary material to "High-frequency productivity estimates for a lake from free-waterCO <sub>2</sub> concentration measurements"
Supplementary material to "High-frequency productivity estimates for a lake from free-waterCO <sub>2</sub> concentration measurements" Open
introduction 2. Section S2: calculation of the eddy covariance CO 2 flux 3. Section S3
View article: Prediction of photosynthesis in Scots pine ecosystems across Europe by needle-level theory
Prediction of photosynthesis in Scots pine ecosystems across Europe by needle-level theory Open
Photosynthesis provides carbon for the synthesis of macromolecules to construct cells during growth. This fact generates the key role of photosynthesis in the carbon dynamics of ecosystems (Taiz et al., 2015) and biogenic CO2 consumption. …