What is the Boreal MiniFACE project?
The Boreal MiniFACE project is a joined effort between Universite de Sherbrooke (UdeS) and Universite du Quebec a Chicoutimi (UQAC) to better evaluate the impact of global climate change on nitrogen cycling in boreal feather mosses.
Why should we investigate the impact of global climate change on boreal forests?
The boreal forest is an economical asset for Canada and a unique component of the world ecosystem. Forestry is a significant part of Canadian economy and the Canadian boreal forest is one of the largest intact forests (1.4 billion acre, 25% of total intact forest). Despite its economic and environmental importance, the boreal forest remains poorly understood and it response to global climate change hard to predict. Climate of the northern hemisphere will undergo significant modifications in the next decades. According to the 2013 IPCC report, by the end of the century the average temperature in boreal and subpolar regions is expected to rise from 3 to 11°C, , the snow and ice cover of the northern hemisphere will be reduced by up to 50 % (based on estimate for sea ice extent in September) and annual precipitation in high latitudes will significantly increase (from 10 to 40% compared to 2005) (scenarii RCP 2.6 and RCP 8.5). How these changes will affect boreal ecosystems is of critical economic and ecological importance. It is thus urgent better evaluate the impact of global climate change on boreal ecosystems.
What is the importance of studying the nitrogen cycle in boreal forest to better predict the effect of global climate change?
In high latitude ecosystems, nitrogen is considered the primary element limiting primary production (Wang 2010) and nitrogen availability will likely constrain the response of these ecosystems to global climate change. For instance, the increase of atmospheric CO2 concentration is expected to create an important carbon sink through the stimulation of ecosystem growth. This carbon sink could contribute to limiting climate change due to anthropogenic activities (Houghton et al, 2001).The extent of this C sink however, strongly depends on nitrogen availability to plants (Reich et al, 2006). The importance of nitrogen availability on the response of boreal tree to global climate change has been demonstrated in a recent study (Sigurdsson et al, 2013).
Why should we investigate the impact of global climate change on feather moss?
The importance of mosses for nitrogen budget (nitrogen fixation) in boreal forests has been recognized in recent years (Deluca et al, 2004). As major contributors to nitrogen input in unmanaged forests, mosses will likely play a important role on the reponse of boreal ecosystems to global climate change. However, the effect of global climate change on nitrogen cycling in mosses remain elussive.The aim of The Boreal Mini Forced-Air CO2 Enriched Project at Simoncouche is to fill this gap in our understanding of nitrogen cycling in boral forest and to allow better predicting the response of this essential ecosystem to global climate change.
To what extend understanding micronutrients dynamics is relevent for better predicting the response of the boreal bryosphere to elevated CO2 and temperature?
It is well established that N2 fixation is limited by the availability of the macronutrient phosphorus (P) (Vitousek et al, 1991 and 1997; Mills et al 2004). This is particularly clear in tropical ecosystems where highly weathered soils are depleted in rock-derived resources (i.e. P). The availability of the micronutrient molybdenum (Mo), an essential metal for nitrogen fixation, can also limit N2 fixation. This is well documented in agricultural systems (Hafner et al, 1992; Gupta, 1997; Srivastava et al, 1998; Vieira et al, 1998). In unmanaged ecosystems, evidence for the limitation of N2 fixation by Mo are scarce: Mo has been found to limit asymbiotic nitrogen fixation in a tropical forest from Panama (Barron et al, 2009), in the coastal temperate forest of northwestern USA (silverster, 1989) and more recently we demonstrated the limitation of asymbiotic nitrogen fixation in cold temperate forest in south of Quebec (Jean et al, 2013). Mo has also been reported to limit nitrogen fixation in cyanobacteria within lichen symbioses (Horstmann et al, 1982) and lakes (Glass et al, 2012; Romero et al, 2013). Our research will evaluate to what extent macronutrient (i.e P) and micronutrient (i.e. Mo) availability control nitrogen fixation by mosses and constrain their response to global climate change.
The Boreal Mini Forced-Air CO2 Enriched Project at Simoncouche is located in Quebec, near the town of Saguenay.
The MiniFACE facility includes 16 Open Top Chambers distributed in 4 subsites . Each subsite includes: a control OTC, an OTC under elevated CO2, an OTC with increased soil temperature and an OTC with both elevated CO2 and temperature. Each OTC is divided in 4 sections recieving 4 treatments; control, + phosphorus, + nitrogen and + micronutrients.