At the station we met warm and friendly atmosphere. The station’s captain Cloud, a friendly and helpful assistant with a Russian name of Ivan, young laughsome and charming scientists Sandra and Stephanie, and a wonderful cooker Christel were a very nice company to adopt the station and to use in full the infrastructure and facilities. Our warmest greetings to all of you, “alligators” (special compellation of Christel)!
In terms of science, we had three main research objectives to be fulfilled during our visit. First one was to characterize photosynthesis of larch tree (Tamarack larch – Larix laricina) in North Canadian permafrost area and compare it with that of Larix cajanderi trees growing in permafrost boreal forests of Central Yakutia, Siberia, Russia. Second task was to estimate soil CO2-emission from natural stands of Tamarack larch in Canada and compare it with that of Yakutian boreal Larix cajanderi forest. And the third objective was to exchange with experiences in research planning, coordination and information, science training of northerners and traditional life knowledge.
With these purposes, we conducted three daily measurements of L.laricina CO2-exchange and soil respiration as well as gathered relevant information from the people at the station, settlement and other scientific groups visiting Kuujjuarapik.
Results of photosynthesis measurements showed that daily net-photosynthesis pattern of L.laricina was late in time and lower in magnitudes compared with the activity of Yakutian larch at this period (for those who eager to know numbers: maxima at 9-12 a.m. with 4-5 µmoles m-2 s-1 and at 8-9 a.m. with 6-10 µmoles for Canadian and Yakutian larch respectively). Foliar respiration taking place in darkness had maxima mainly within 2-5 p.m. of up to -4 µmoles m-2 s-1. With common assumptions, considering just three day measurements and many coinciding data for L.cajanderi, being under observation for more than 10 years, we conclude that diurnal patterns of L.laricina in terms of visible photosynthesis and dark respiration are close to that of Yakutian larch species despite different growing conditions. As for other photosynthetic parameters (light compensation and saturation points, CO2-saturated maximal photosynthesis, maximal carboxylation efficiency and electron transport rates), we think them to be enough different, diverging by 2-3 times mainly in favor of Yakutian larch.
Soil under natural stands of L.laricina had maxima of CO2-efflux (0.45-0.60 g CO2 m-2 h-1) at nighttime (2-4 a.m.) but quantitatively the sum of nighttime CO2 emission was 3 times as less as the daytime sum, which varied from 7 to 8.5 g CO2 m-2 day-1 bringing to the preliminary estimated accumulated sum of CO2-efflux of up to 1000 g CO2 m-2 season-1. It seems to us that it is very high, even comparing to 800 g CO2 m-2 season-1 flux in South-Eastern Yakutia. Soil biota activity seems to be not highly limited by soil temperature that indicates on well adoption of soil biota to the specific climatic conditions of the site.
Concluding, the station is obviously unique worldwide, has state-of-the-art instrumentation and provides excellent logistical infrastructure to perform continuous monitoring as well as extensive field campaigns, and quite many scientific findings have been produced at the site.
We would like to express our admiration and many thanks to the station staff for their helpful efforts during our stay here from 18 to 27 June 2012, and hope that our studies on carbon cycling of boreal forests will add another exclusive data to already impressive collection of CEN Hudson Bay station at Whapmagoostui-Kuujjuarapik.
With the best wishes,
Trofim Maximov, Dr.Sci., Head and Ayal Maksimov, Researcher
Laboratory of BioGeoChemical Cycles of Permafrost Ecosystems, IBPC; International Center BEST (Biogeoscience Educational and Scientific Training) of North-Eastern Federal University, Yakutsk; Spasskaya Pad and Chokurdakh scientific stations of IBPC.
*The team visited CEN Hudson Bay Field station at Whapmagoostui-Kuujjuarapik with a grant from The Centre for Northern Studies (CEN), a Canadian partner in INTERACT.