Affiliation: University of Helsinki
- Flux and concentration footprint modelling: state of the artT Vesala
Department of Physical Sciences, University of Helsinki, PO Box 64, FIN 00014 Helsinki, Finland
Environ Pollut 152:653-66. 2008..The estimation of footprints for application in the real world, complete with a multitude of interesting gaseous and particulate substances, remains a complex problem...
- Refilling of a hydraulically isolated embolized xylem vessel: model calculationsTimo Vesala
Department of Physical Sciences, PO Box 64, FIN 00014, University of Helsinki, Finland
Ann Bot 91:419-28. 2003..95) and the ratio of the volume of the adjacent living cells to that of the embolized vessel is about 2, does the osmotic potential stay below 0.4 MPa...
- Assimilate transport in phloem sets conditions for leaf gas exchangeEero Nikinmaa
Departments of Forest Sciences, University of Helsinki, Helsinki FI 00014, Finland
Plant Cell Environ 36:655-69. 2013..It produces similar behaviour as the optimal stomatal control approach, but does not require determination of marginal cost of water parameter...
- The dependence of the beta coefficient of REA system with dynamic deadband on atmospheric conditionsTiia Grönholm
Department of Physical Sciences, University of Helsinki, P O Box 64, FIN 00014, Finland
Environ Pollut 152:597-603. 2008..42+/-0.03. For a single half-hour measurement one has to consider the large uncertainty of +/-0.2. According to our study, the dynamic deadband enables the use of a constant value of beta in flux calculation...
- CO2 fluxes near a forest edge: a numerical studyAndrey Sogachev
Department of Physics, University of Helsinki, P O Box 64, Helsinki FI 00014, Finland
Ecol Appl 18:1454-69. 2008..These results can be useful both for interpretation of existing measurements of net ecosystem exchange of CO2 (NEE) from flux towers in limited fetch conditions and in planning future CO2 transport experiments...
- Nitrous oxide emissions from a municipal landfillJanne Rinne
Department of Physical Sciences, P O B 68, FI 00014 University of Helsinki, Finland
Environ Sci Technol 39:7790-3. 2005..The emissions measured by the two systems were generally of similar magnitude, with enclosure measurements showing a high small-scale spatial variation...
- Atmospheric science: Ultraviolet light and leaf emission of NO(x)Pertti Hari
Department of Forest Ecology, University of Helsinki, 00014 Helsinki, Finland
Nature 422:134. 2003
- Temperature dependence of leaf-level CO2 fixation: revising biochemical coefficients through analysis of leaf three-dimensional structureEija Juurola
University of Helsinki, Department of Forest Ecology, PO Box 27, FIN 00014 University of Helsinki, Finland
New Phytol 166:205-15. 2005..The influence of three-dimensional leaf structure on the light environment inside a leaf is marked and affects the local choice between Jmax and V c(max)-limited assimilation rates...
- Wintertime photosynthesis and water uptake in a boreal forestSanna Sevanto
Department of Physical Sciences, P O Box 64, 00014 University of Helsinki, Finland
Tree Physiol 26:749-57. 2006..The more difficult it was to access soil water because of low Ts or low theta, the longer the trees used water stored in their stems. Even partial stem freezing did not prevent photosynthesis or soil water uptake...
- Modeling the dynamics of pressure propagation and diameter variation in tree sapwoodMartti Perämäki
Department of Forest Ecology, University of Helsinki, P O Box 27, 00014 University of Helsinki, Finland
Tree Physiol 25:1091-9. 2005..The effect of tree dimensions on pressure propagation was examined with the model. The model outcomes were also consistent with results of several field measurements presented in the literature...
- Plant-mediated nitrous oxide emissions from beech (Fagus sylvatica) leavesMari Pihlatie
Department of Physical Sciences, University of Helsinki, FIN 00014 Helsinki, Finland
New Phytol 168:93-8. 2005..Our experiments demonstrate the existence of a previously overlooked pathway of N2O to the atmosphere in forest ecosystems, and bring about a need to investigate the magnitude of this phenomenon at larger scales...
- Micrometeorological measurements of methane and carbon dioxide fluxes at a municipal landfillAnnalea Lohila
Climate and Global Change Research, Finnish Meteorological Institute, P O Box 503, FI 00101 Helsinki, Finland
Environ Sci Technol 41:2717-22. 2007..24) when the emission originated from the area with no oxidizing cover layer and being smaller when CH4 oxidation had taken place...
- Net carbon dioxide losses of northern ecosystems in response to autumn warmingShilong Piao
LSCE, UMR CEA CNRS, Bâtiment 709, CE, L Orme des Merisiers, F 91191 Gif sur Yvette, France
Nature 451:49-52. 2008..If future autumn warming occurs at a faster rate than in spring, the ability of northern ecosystems to sequester carbon may be diminished earlier than previously suggested...