In this
recent paper (Biogeosciences discussion:
10, 3735-3847, 2013) « Estimating
global carbon uptake by lichens and bryophytes » P. Porada (Institute
for Biogeochemistry in Jena) and co authors present the first process-based
model to estimate the Net Carbon uptake by bryophytes and lichens at a global
scale, and consequently assessing their role in biogeochemical cycles.
Elbert et
al (2012) in “Contribution of cryptogamic covers to the global cycles
of carbon and nitrogen” (Nat Geosci, 5: 459-462) suggest that cryptogamic
plants as lichens and bryophytes contribute largely to biogeochemical cycles,
from field and lab experiments they estimate for global net Carbon uptake
amounts to 7% of terrestrial net primary productivity (NPP), the derived value
of nitrogen fixation corresponds to around 50 % of the terrestrial uptake,
significant impact on the global nitrogen cycle.
Lenton et
al. (2012) in their paper entitled “ First plants cooled the Ordovician” (Nat.
Geosci, 5: 86-89) focus on the effects of the predecessors of modern bryophytes
on atmospheric CO2 concentration during the Ordovician. They showed
that these early non-vascular land plants could have caused a considerable
drawdown in atmospheric CO2 levels via the silicate weathering
feedback and consequently a decrease in global surface temperature. The release
of phosphorus from the weathered rocks into the oceans could have led to rise
in marine productivity and therefore to further cooling...
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