@ARTICLE{Barták_Miloš_Photosynthetic_2012,
 author={Barták, Miloš and Váczi Peter and Hájek, Josef},
 number={No 4},
 journal={Polish Polar Research},
 pages={443-462},
 howpublished={online},
 year={2012},
 publisher={Polish Academy of Sciences},
 publisher={Committee on Polar Research},
 abstract={Diurnal measurements of photosynthetic pr ocesses, effective quantum yield of photosystem II ( F PSII ), photosynthetic electron transport rate (ETR) were done in three domi− nant species of Arctic tundra ( Silene acaulis , Dryas octopetala , Salix polaris ) in Petunia− bukta, Spitsbergen. Daily courses of net photosynthesis (P N ) were calculated from chloro− phyll fluorescence data and daily photosynthesi s evaluated. The short−term field measure− ments were carried out in summer 2009, and 2010. Fluorometric parameters ( F PSII and ETR) were measured each 5 minutes as well as microc limate characteristics of the site for 10 (2009) and 8 days (2010), respectively. In all species photosynthetic ETR was well related to incident photosynthetically active radiation a nd leaf temperature. In general, D. octopetala exhibited slightly lower ETR than the other two speci es. Estimated maximu m photosynthetic rate (P Nmax ) reached 17.6, 21.4, and 22.9 μmol CO 2 m −2 s −1 for S. polaris , S. acaulis ,and D. octopetala , respectively. Daily photosynthesis reach ed comparable values in all species, D. otopetala , however, exhibited slightly lower values than the other two species both for overcast and fully sunny days (3.9 and 13.4 mmol CO 2 m −2 d −1 , respectively). The range of daily photosynthesis for S. polaris and S. acaulis studied, reached the ranges of 4.6–6.9 and 14.6–15.2 mmol CO 2 m −2 d −1 for overcast and fully sunny day, respectively.},
 type={Artykuły / Articles},
 title={Photosynthetic activity in three vascular species of Spitsbergen vegetation during summer season in response to microclimate},
 URL={http://www.czasopisma.pan.pl/Content/99537/PDF/v10183-012-0018-z.pdf},
 doi={10.2478/v10183−012−0018−z},
 keywords={Arctic, Svalbard, vascular plants, plant ecophysiology, net photosynthesis, chlorophyll fluorescence},
}