Transcript Carbon Sequestration in 4 Soil Types

CARBON SEQUESTRATION IN DOUG-FIR
FORESTS ON GLACIAL AND VOLCANIC
SOILS IN THE PACIFIC NORTHWEST
University of Washington Soils Lab
A.B. Adams & Rob Harrison
Funded by DOE CENTER FOR RESEARCH ON ENHANCING
CARBON SEQUESTRATION IN TERRESTRIAL ECOSYSTEMS
CSITE
C SEQUESTRATION RELATED HYPOTHESES
• Fertilizer increases tree
biomass accumulation
• Fertilizer increases soil
carbon transport to deeper
depths in the soil profile
• Following fertilization,
volcanic sites (finetextured) soil carbon
accumulation > and
deeper than glacial
(coarse) soil
FOUR (surface, A, B & C) LYSIMETERS INSTALLED IN
CONTROL AND UREA FERTILIZED PLOT WITH SMC
• GLACIAL SITES
Port Gamble - est. 1975; fertilized w/ 200 lbs/acre at 8 yrs and
every 4 yrs after up to 1200 lbs/acre; thinned to 300 tpa
Cedar River - est. 1972; fertilized w/ 200 lbs/acre at 8 yrs and
every 4 yrs after up to 1200 lbs/acre; thinned to 60% of basal
area
• VOLCANIC SITES
Mud Mountain - est. 1980; fertilized w/ 200 lbs/acre at 8 yrs and
every 4 yrs after up to 1,200 lbs/acre; thinned to 300 tpa
Radio Hill - est. 1980; fertilized w/ 200 lbs/acre at 8 yrs and
every 4 yrs after up to 1,200 lbs/acre; thinned to 300 tpa
LEACHATE COLLECTIONS FROM 4
TENSION LYSIMETERS AT ONE PLOT
• A horizon least
reliable
• B horizon color varies
• C or deep B horizon
most predictable (good
yield and colorless)
• O horizon darkest
As horizons were extracted and sieved with the 25mm
screen, the components were weighed in the field. This
is material from the Bw horizon of Barneston (glacial)
As seen with this rocky Barneston soil, pits were dug to roughly a meter.
Depths from the midpoint of each side to tops and bottoms of each
horizon were measured. Means of these 4 measurements were used as
water displacement levels for horizons.
Poulsbo soil series, Port Gamble, WA
Sandy glacial with E horizon
• Very thin E horizon
• Deep sand
• Sand very compacted
at lower depths
• Thin forest floor
• Low understory cover
• Olympic Mts.
rainshadow effect
POULSBO SANDY LOAM
SPODIC HORIZON
Undetermined volcanic soil series, Mud Mt., WA.
Ashy loam with no rocks
• Thick forest floor
• Decaying roots and
tunnels present
• Low bulk densities
even at deepest depths
Winston soil series, Radio Hill, WA.
Ashy loam with some rocks
• Deep ashy loam
• Deep lysimeter in or just
above 2C glacial horizon
• Some rocks
• Larger forest floor
• At all plots, 3mm sieve used
to screen for soil to pack
around porous ceramic
lysimeter cups
COARSE
ALDERWOOD
FRAGMENT DISTRIBUTION FOR BARNESTON AT
CEDAR RIVER INSTALLATION
% Fragment Size (mm)
Horizon by Depth (CR)
0
A
10
20
30
40
50
60
25mm
19
Bw
11
4
2
Bm
<2mm
COARSE FRAGMENT DISTRIBUTION FOR 3 DEPTHS
AT RADIO HILL INSTALLATION SHOWING DOMINANCE
OF THE <2mm COMPONENT
% Fragment Size (mm)
Horizon by Depth
0
A
10
20
30
40
50
60
25
19
11
B2
4
2
<2
B5
100
100
80
RH4A
Volcanic Control (RH)
DOC (mg/L)
RH4FF
DOC (mg/L)
RH4B
RH4C
60
40
CR3FF
80
CR3A
60
CR3C
Glacial Control (CR)
CR3B
40
20
20
0
0
JAN
FEB MAR APR MAY
JUN
JAN
JUL
FEB MAR APR MAY JUNE JULY
100
80
Volcanic Fertilized (RH)
60
40
DOC (mg/L)
DOC (mg/L)
100
80
60
40
20
20
0
0
JAN FEB MAR APR MAY JUNE JULY
Glacial Fertilized (CR)
JAN FEB MAR APR MAY JUN JUL
SUMMARY
• DOC detected in epipedon decreases with depthDIC
exhibits spatial and temporal variation
• Texture is a factor in results, but study does not consider
mineralology
• Volcanic soils have lower percent of hydrophilic (labile)
substances, particularly in deeper lysimeters
• Fertilizer may have more effects on C dynamics with finer
textured soil (volcanic)