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Bobrik Anna*, Goncharova O., Matyshak G., Ryzhova I., Ponomareva O., Ogneva O.
Department of Soil Science, Lomonosov Moscow State University, Moscow, Russia, *[email protected]
Spatial and temporal variability of CO2 efflux of frozen peatland soils at fine scale (Russia, CALM SITE R1)
The main question
Research area is located on the north of
Western Siberia (Nadym District, Russia)
within the northern boundary of north taiga, in
the contour part of the 3rd lacustrine-fluvial
plain of the Nadym River. It’s zone of
discontinuous permafrost. It’s absent in
forest and present under peatlands.
Conclusion
•Unique Nadym site consists of different types of ecosystems
which function in different geocryological conditions. Permafrost-
affected soils are characterized by low biological activity.
•Active layer thickness and soil CO2 effluxes are characterized by
high spatial and low temporal variability.
•We consider the main factor which determine the soil carbon
efflux is the depth of permafrost table, it determines the type of
ecosystem in such transitional landscapes and organic matter
transformation processes.
•Underestimation of the spatial variability of soil and vegetation
cover in the region of discontinuous permafrost can lead to
substantial distortion of estimates of the total greenhouse gases
balance.
Research area
1-ha (100m*100m) grid (N65°20',
E72°55’) consists of a square array
of permanent stakes separated by
10 m (121 data points per grid for
all measurements). Permafrost is
closely associated with frozen
peatlands, bog and frost mounds.
The typical soils are Turbic Cryosol
of young frozen peatland and
Histosols of bog.
Key references 1) Goncharova, O.Yu., Matyshak, G.V., Bobrik, A.A., Moskalenko, N.G., 2014. Carbon
dioxide production by northern taiga soils of Western Siberia (Nadym site). Earth
Cryosphere, 18, 66–71, 2) Goncharova, O.Yu., Matyshak, G.V., Bobrik, A.A., Moskalenko,
N.G., 2015. Soils thermal regime in sporadic permafrost areas (Western Siberia, Russia).
Eurasian Soil Science, In Press.
m
%
0
50
100
150
200
250
300
350
400
450
500
50
80
110
140
170
200
Frozen
peatland
Spatial and temporal variability of
permafrost table depth and carbon dioxide
efflux
mgСО2 m-2 h-1
Efflux of CO2
0 10 20 30 40 50 60 70 80 90 100
0
10
20
30
40
50
60
70
80
90
100
0 10 20 30 40 50 60 70 80 90 100
0
10
20
30
40
50
60
70
80
90
100
0 10 20 30 40 50 60 70 80 90 100
0
10
20
30
40
50
60
70
80
90
100
0 10 20 30 40 50 60 70 80 90 100
0
10
20
30
40
50
60
70
80
90
100
Aug, 2013 Aug, 2014
Depth of permafrost
table
Based on the regression analysis among more than 10 characteristics
(hydrothermal, geocryological, soil) for CALM R1 site was revealed high
and significant correlation carbon dioxide efflux with microbial biomass
carbon in the upper 10 cm soil layer (beta=0,965; p-level<0,05) and
with the permafrost table depth (beta=0,333; p-level<0,05).
0
1
2
4
6
8
10
mg g -1 soil
MC, Aug 2013 0 10 20 30 40 50 60 70 80 90 100
0
10
20
30
40
50
60
70
80
90
100
WEOC, Aug 2013 0
0.15
0.3
0.45
0.6
0.75
0.9
%, of TOC
6
11
16
21
26
31
36
41
46
TOC, Aug 2013
The values of microbial biomass are high, but geocryological and
hydrothermal conditions inhibit all soil biological processes. Permafrost-
affected soils of peatlands are characterized by the low biological
activity which leads to the preservation of organic matter, so these
ecosystems are the sink of carbon.
CALM landscape
0 10 20 30 40 50 60 70 80 90 100
0
10
20
30
40
50
60
70
80
90
100
0
0.3
0.6
0.9
1.2
1.5
0 10 20 30 40 50 60 70 80 90 100
0
10
20
30
40
50
60
70
80
90
100
5
25
45
65
85
Relief
Bog
T1
B, BC
T2
T1
O
Volumetric soil moisture
content, Aug 2014
Active
laye
r P
erm
afr
ost
+ content of the total organic carbon (TOC),
carbon of water - extractable organic matter
(WEOC) (extraction of 0.005M K2SO4), carbon of
microbial biomass (MC) in the upper 10 cm of soil
(by chloroform fumigation–extraction (FE) method)
and common soil properties were analized in
laboratory
Regime monitoring of the carbon dioxide efflux
from the soil surface (close non-steady-state
non-through-flow chambers method)
Measurement
of active layer
thickness
The Circumpolar Active Layer Monitoring (CALM) program developed over the last
decade as a leading edge in comprehensive efforts to study the impacts of climate
change in permafrost environments. CALM sites are convenient for the study of
spatial and temporal variation of soil parameters at fine scales.
What does determine biological activity and function of permafrost-affected soils?
Mean= 0,27±0,05
%
m
Mean=135±35 Mean=145±25
Mean=61,70±20,50
Mean=124±10 Mean=115±15
0 10 20 30 40 50 60 70 80 90 100
0
10
20
30
40
50
60
70
80
90
100
0 10 20 30 40 50 60 70 80 90 100
0
10
20
30
40
50
60
70
80
90
100
Mean=36,50±10,50
Mean=3,00±0,20
Properties of SOM Methods
Mean=0,54±0,20
CALM R1
+ regime monitoring of the temperature of air, soil surface and soil
(Thermochron iButtonTM ); description of soil and vegetation cover
There is significant intra site variation
in near-surface soil moisture content.
Soil moisture is strongly correlated with
relief (beta= -0,801; p-level<0,05).
Acknowledgments Financial support was provided
by the Russian Foundation for
Basic Research, grant RFBR
№13-04-01577 “Cryogenesis is
a subfactor of soil formation on
north of Western Siberia”.