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Measurement of root inputs: Allt a’ Mharcaidh, Invercauld and
IndonesiaL D IndonesiaLorna DawsonSebastian PerschRachel HelliwellAndrea BrittonAndrea BrittonJasmine RossRuth Mitchell
REDD‐ALERT Peat Dynamics workshop, TJHI 31/8/11 and 1/9/11
Five/six habitats along a boreal‐alpine toposequence
50
60
Soil mineral horizonsSoil organic horizonsSite 5
ol k
g m
-2 40
50RootsLitter Above ground biomass
Car
bon
poo
20
30
Site 1
Site 2
Site 3
Site 4
et mirel heath
heathowbed
heath0
10
Blanket m
Boreal he
Alpine heSnow
Racomitrium he
Britton, A.J.; Helliwell, .C.; Lilly, A.; Dawson, L.A.; Fisher, J.M.; Coull, M.C.; Ross, J 2011.An integrated assessment of ecosystem carbon pools and fluxes across an oceanic alpine toposequence ‐ ‐ Plant and Soil 345 287‐302toposequence. . Plant and Soil, 345, 287 302.
C storage
How C storage works Plants fix CO2
CO2 Plants fix CO2
C moves into soil pool as litter
C t d i litt i & i l C stored in litter, organic & mineral horizons
S il i l & i b Soil animals & microbes use organic matter as food source & produce CO22
C storage depends on balance between fixation & decomposition
Factors controlling C storage
Litter quality – plant species vary in terms of nutrients (C, N, P) in litter
Soil biota – community size, composition & activity Climate – soil temperature & moisture & their variability p ydirectly affect chemical processes, leaching & erosion
Pollution – N deposition and acidification affect chemical processes
Interactions – climate & pollution alter microbial community activity plant litter quality species present (plants &activity, plant litter quality, species present (plants & microbes)
C storage = Fixation DecompositionC storage = Fixation ‐ Decomposition All habitats hold large
l60 soil C stores
Mire is most important ll
50
60
Soil mineral horizonsSoil organic horizonsRootsLitt store overall
Alpine zone holds more th i ti tpo
ol k
g m
-2
30
40LitterAbove ground biomass
than previous estimates
Snowbed holds largest C t i l i
Car
bon
p
20
store in alpine zone
ire th th bed th0
10
Blanket mireBoreal heath
Alpine heathSnowbed
Racomitrium heath
C Storage Fixation DecompositionC Storage = Fixation ‐ Decomposition
Matches pattern of C250 Matches pattern of C storage
Soil C store = 200‐300 times annual
200
250
300 times annual production
Wet habitats most productiveC
m-2
y-1
150
productive Alpine habitats can be as productive as boreal
NPP
g
50
100
boreal
mire eath eath bedeath
0
50
Blanket mir
Boreal heat
Alpine heatSnowbed
Racomitrium heat
C storage = Fixation DecompositionC storage = Fixation ‐ Decomposition Surface‐placed litter
70
Rates vary greatly between habitats60
Racomitrium heathSnowbedAlpine heathBoreal heathBlanket mire
Alpine habitats include fastest & slowest decompositions
loss 40
50 Blanket mire
decomposition
Habitat type more important than temperature gradient
% m
ass
20
30
than temperature gradient (ca. 2°C)
10
20
No. months incubation
0 6 12 18 24 30 360
S W S W S
Projected climate change in Scotland(2080 – Medium high emissions)
Temperature: +2 to +3.5°C
( g )
p Rainfall: 0 to ‐10%
(↑ winter, ↓ summer) Soil moisture: 0 to ‐20%
(↑ winter, ↓ summer)f ll Snowfall: ‐50 to ‐90%
Impacts of climate change: short term
Change Fixation Decomposition C storeChange Fixation Decomposition C store↑Temperature ↑ ↑ ?↑ ↑↓Soil moisture (dry habitats) ↓ ↓ ?( y )↓Soil moisture (wet habitats) ↓ ↑ ↑ ?Loss of snow cover (snowbeds) ↑ = ?
There are many uncertainties – we need to understand more about how species & processes will respond above andabout how species & processes will respond above and belowground
C l iConclusions
l h b h h ldAlpine habitats in oceanic areas such as UK hold considerable C stocks
C k i ll i bl h bi h C stocks are spatially variable, wet habitats such as snowbeds and blanket bog are important
Cli t h ff t h bit t di t ib ti ill i t Climate change effects on habitat distribution will impact C storage
C t l f th f t h N d iti ill b Control of other factors such as N deposition will be important in maintaining C stocks
Soil Properties and soil water DOC : Allt a’ Mharcaidh transectAllt a Mharcaidh transect
Site
Organic soil (cm)
Above-tray Mass C
(kg/m²)%C C:N
(molar)
tude
900m(kg/m ) (molar)
1 8 4.6 13.1 54.1 2 22 6.4 32.2 26.1 3 vegetation 6 3.5 8.3 39.5 3 gravel 0 2 0 4 3 31 6
Altit
490m
3 gravel 0 2.0 4.3 31.64 30 11.4 39.0 38.0 5 96 6.9 49.0 63.9 6 9 7.2 29.8 38.7
S= Summer
Key messages:
The weak relationship between soil water DOC and above‐tray soil carbon pools highlights the potential pitfalls of using DOC as a S Summer
W= Wintercarbon pools highlights the potential pitfalls of using OC as aproxy for C pool
Clear seasonal signal in DOC, with maximum concentrations observed in the warmer months reflecting microbial breakdown of organic matterorganic matter
An inter‐site comparison demonstrates a strong relationship between DOC and net primary productivity with the greatest NPP (at the warmer lower altitude sites) generally showing a more pronounced increase in DOC
Sites
Relationship between temperature and root DOCroot DOC
Sample collection and monitoring: Invercauld
Precipitation ol mes and
Zero‐tension lysimeters used to collect soil Root dynamics volumes and
chemistry, temp,
used to collect soil solution from HE horizon at 10cm
y
moisture
Root appearance and death
Site 4 root production 2009 Site 4 root death 2009
250
300
Site 4 root production 2009
9 250
300
9
150
200
no/cm3
10
11
12
13150
200
no/cm3
10
11
12
13
50
100 14
15
16 50
100 14
15
16
0 0
Time of year; start May to end October Time of year; start May to end October
Root Carbon dynamics‐ site 3Root Carbon dynamics site 3
0.6
0.7
0.8
0.3
0.4
0.5
mg/cm3 est. root C lost
0
0.1
0.2mg/cm3 est.root C production
InvercauldInvercauld
InvercauldExperimental set up•4 blocks
Measurements made:•Soil respiration
•Within each block a grazed andungrazed treatment (plot)
•Within each grazed or ungrazed
•Soil water chemistry (DOC) plus other chemical content (data on volume is a bit variable as bottles often over-flowed)
•Within each grazed or ungrazedplot 3 treatments:•Heather control•Planted birch
•Root growth
•Root C and N•Planted pine•Each pine, birch, heather plot is 19 x 16m
•Soil temperature•Soil moisture•Weather data
DOC time trends
25
30
35
10
15
20
DOC m
g/l
B
C
P
0
5
10/04/20
06
10/06/20
06
10/08/20
06
10/10/20
06
10/12/20
06
10/02/20
07
10/04/20
07
10/06/20
07
10/08/20
07
10/10/20
07
10/12/20
07
10/02/20
08
10/04/20
08
10/06/20
08
10/08/20
08
10/10/20
08
10/12/20
08
10/02/20
09
10/04/20
09
10/06/20
09
10/08/20
09
10/10/20
09
10/12/20
09
10/02/20
10
10/04/20
10
10/06/20
10
10/08/20
10
1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1
25
30
35
/l
10
15
20
DOC m
g/
Grazed
Ungrazed
0
5
0/04
/200
6
0/06
/200
6
0/08
/200
6
0/10
/200
6
0/12
/200
6
0/02
/200
7
0/04
/200
7
0/06
/200
7
0/08
/200
7
0/10
/200
7
0/12
/200
7
0/02
/200
8
0/04
/200
8
0/06
/200
8
0/08
/200
8
0/10
/200
8
0/12
/200
8
0/02
/200
9
0/04
/200
9
0/06
/200
9
0/08
/200
9
0/10
/200
9
0/12
/200
9
0/02
/201
0
0/04
/201
0
0/06
/201
0
0/08
/201
0
1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1
Relationships between DOC and soil temperature
50
40
45I1HB I1HC I1HP
I1UB I1UC I1UP
25
30
35
OC
I2HB I2HC I2HP
I2UB I2UC I2UP
15
20
25
DO
I3HB I3HC I3HP
5
10I3UB I3UC I3UP
I4HB I4HC I4HP
0
‐4 ‐2 0 2 4 6 8 10 12 14 16 18
Average soil temperature during preceeding 6 weeks
I4UB I4UC I4UP
CO2 and soil temperatureCO2 and soil temperature
700
800
900
h‐1)
300
400
500
600
verage
mg C
O2 m
‐2 h
Birch
Heather
0
100
200
300
8 9 9 9 9 9 9 9 9 9 9 9 9 9 9 9 9 9 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
CO2 (av eat e
Pine
29/1/200
826
/1/200
911
/3/200
924
/3/200
96/4/20
0919
/4/200
915
/5/200
95/6/20
0918
/6/200
91/7/20
0914
/7/200
927
/7/200
917
/8/200
922
/9/200
95/10
/200
918
/10/20
0926
/11/20
0913
/12/20
096/2/20
1011
/3/201
030
/4/201
013
/5/201
026
/5/201
010
/6/201
027
/6/201
012
/7/201
025
/7/201
07/8/20
1023
/8/201
05/9/20
1018
/9/201
09/10
/201
030
/10/20
10
18
8
10
12
14
16
mp (oC
) at 5
cm
Birch
0
2
4
6
8
soil t
em
Birch
Heather
Pine
0
29/1/200
823
/1/200
922
/2/200
915
/3/200
925
/3/200
94/4/20
0914
/4/200
97/5/20
0917
/5/200
94/6/20
0914
/6/200
924
/6/200
94/7/20
0914
/7/200
924
/7/200
94/8/20
0911
/9/200
923
/9/200
93/10
/200
913
/10/20
0923
/10/20
0928
/11/20
0912
/12/20
092/2/20
1012
/2/201
08/4/20
1030
/4/201
010
/5/201
020
/5/201
030
/5/201
011
/6/201
025
/6/201
07/7/20
1017
/7/201
027
/7/201
06/8/20
1019
/8/201
029
/8/201
08/9/20
1018
/9/201
06/10
/201
024
/10/20
103/11
/201
0
Root measurementsRoot measurements
Invercauld Root Production 2007
2
Birch
Heather
Pine
1
1.5
/cm
3/da
y
Invercauld Root Loss 2007
Birch Heather0
0.5
ay ay un un Jul
Jul
Jul
ug ug ep ep Oct
Oct
no/
1.5
2
/day
Pine08-M
a
22-M
a
05-J
u
19-J
u
03-J
17-J
31-J
14-A
u
28-A
u
11-S
e
25-S
e
09-O
23-O
0.5
1
no/c
m3/
0
08 -… 22 -… 05 -… 19 -… 03 -… 17 -… 31 -… 14 -… 28 -… 11 -… 25 -… 09 -… 23 -…
Indonesia‐ Sebastian’s PhDIndonesia Sebastian s PhDThe objective of this study is to assess how the transition associated with logging a primary peat swamp forest and establishing oil palm plantation affects the contribution of fi t t th t b lfine roots to the ecosystem carbon cycle.
The aims are
(i) to estimate the fine root production, mortality, decomposition and exudation in an intact primary forest, p p y ,a logged forest, and an oil palm plantation, and
(ii) to assess the contribution of the fine roots to the total (ii) to assess the contribution of the fine roots to the total CO2 emissions from land use change.
Transition with logging a primary peat swamp forest and establishing oil palm plantationforest and establishing oil palm plantation
Primary forest
Secondary logged forest
The research components: (1) Fine root turnover (i e production and
Oil palm plantation
(1) Fine root turnover (i.e. production and mortality), (2) fine root decomposition
Samplingp g In each treatment a stratified sampling will be carried out using hollows and hummock as
strata in the 2 forest treatments and different distances from the trunk in the oil palm treatment (i.e. close to the trunk (0.5m), quarter‐distance (2.25m), and mid‐distance between to palms (4.5m)).
10 transparent tubes (per site)will be placed at randomly selected points in the forest 10 transparent tubes (per site)will be placed at randomly selected points in the forest treatments and at randomly selected palms in the OP treatment. (5 per stratum, 70mm in diameter, 118cm length [to cover the first 50cm of soil depth] installed in an angle of 45˚)
Analyzing program: WinRHIZO will be used and will be carried out in parallel with filming
Calculation of root turnover rate
Relative root length increase and relative root length loss (RRLL)
Relative annual root loss rates (RRLR) as according to Nadelhoffer (2000):
RRLR= (mean RRLL*12)/100
Annual root loss rate = root turnover
Root longevity as the inverse value of annual root loss rate
Thank You Biomass coring
Necromass coring Necromass coring
Litterbag decomposition
And relationships to other variables and integration in models……………………
Thanks to RERAD for funding and Julia Fischer, Kenny Hood and Richard Gwatkin for support