Post on 02-Jan-2016
description
• Site I - Post Harvest
• Site II - Pre Harvest
• Site II - Post HarvestCumulative Effects
Iron Canyon Soil Monitoring
Iron Canyon IIFeller-Buncher Harvesting
August 2003, 23% Soil H20 at 0-60 cm
Pre-Harvest
Undist 675
Dist 216
Skid 109
Iron Canyon II Soil MonitoringPre- vs. Post-Harvest Disturbance
Units- Feet (1,000 ft total in transects)
undist67%
dist22%
skid11%
Disturbance Class Matrix
Post-Harvest
Undist Dist SkidPre-Harvest
Undist 675
Dist 216
Skid 109
Iron Canyon II Soil MonitoringPre- vs. Post-Harvest Disturbance
Units- Feet (1,000 ft total in transects)
Disturbance Class Matrix
Post-Harvest
Undist Dist SkidPre-Harvest
Undist 675 157
Dist 216
Skid 109
Iron Canyon II Soil MonitoringPre- vs. Post-Harvest Disturbance
Units- Feet (1,000 ft total in transects)
Disturbance Class Matrix
Post-Harvest
Undist Dist SkidPre-Harvest
Undist 675 157 411 107
Dist 216
Skid 109
Iron Canyon II Soil MonitoringPre- vs. Post-Harvest Disturbance
Units- Feet (1,000 ft total in transects)
Disturbance Class Matrix
Post-Harvest
Undist Dist SkidPre-Harvest
Undist 675 157 411 107
Dist 216 46 147 23
Skid 109
Iron Canyon II Soil MonitoringPre- vs. Post-Harvest Disturbance
Units- Feet (1,000 ft total in transects)
Disturbance Class Matrix
Post-Harvest
Undist Dist SkidPre-Harvest
Undist 675 157 411 107
Dist 216 46 147 23
Skid 109 12 49 48
Iron Canyon II Soil MonitoringPre- vs. Post-Harvest Disturbance
Units- Feet (1,000 ft total in transects)
Disturbance Class Matrix
2003-Harvest
Undist Dist Skid
1960’s-Harvest 215 607 178 Cumulative
Undist 675 157 411 107 157 Undist
Dist 216 46 147 23 604 Dist
Skid 109 12 49 48 239 Skid
Iron Canyon II Soil MonitoringPre- vs. Post-Harvest Disturbance
Units- Feet (1,000 ft total in transects)
Disturbance Class Matrix
PREHarvest
POSTHarvest % Change
Undist 67% 16% -77
Dist 22% 60% +180
Skid 11% 24% +119
Iron Canyon II Soil MonitoringPre- vs. Post-Harvest Disturbance
Percent Change in Pre-Harvest Classes
Iron Canyon II Soil MonitoringPost-Harvest Disturbance Extent
undist16%
dist60%
skid24%
undist67%
dist22%
skid11%
PRE
POST
Iron Canyon II Soil MonitoringPost-Harvest Disturbance
March 2004 (47% Soil Moisture)0
10
20
30
40
50
60
0 1000 2000 3000 4000
STRENGTH (kPa)
DE
PT
H (
cm
)
undist
dist
skid
landing
Iron Canyon II Soil MonitoringPost-Harvest Disturbance
Soil Strength Through the Growing Season (10-20 cm)
0
500
1000
1500
2000
2500
3000
3500
4000
Oct-02
Dec-02
Feb
-03
Ap
r-03
Jun
-03
Au
g-03
Oct-03
Dec-03
Feb
-04
Ap
r-04
Jun
-04
Au
g-04
SO
IL S
TR
EN
GT
H (
kP
a)
skid
dist
undistharvest
Iron Canyon II Soil MonitoringSoil Strength Before & After Harvest
0
1000
2000
3000
4000
Undist Dist Skid
PRE-HARVEST DISTURBANCE CATEGORY
ST
RE
NG
TH
(k
Pa
)
PRE
POST
10 Month Averages at 10-20 cm
Disturbance Class Matrix
Post-Harvest
Undist Dist SkidPre-Harvest
Undist 675 157 411 107
Dist 216
Skid 109
Iron Canyon II Soil MonitoringPre- vs. Post-Harvest Disturbance
Units- Feet (1,000 ft total in transects)
Iron Canyon II Soil MonitoringSoil Strength Before & After Harvest
0
1000
2000
3000
4000
Undist Dist Skid
PRE-HARVEST DISTURBANCE CATEGORY
ST
RE
NG
TH
(k
Pa
)
PRE
POST
10 Month Averages at 10-20 cm
Iron Canyon II Soil MonitoringBulk Density Before & After Harvest
0.0
0.2
0.4
0.6
0.8
1.0
1.2
Undist Dist Skid
PRE-HARVEST DISTURBANCE CATEGORY
BU
LK
DE
NS
ITY
(g
/cm
3 )
PRE POST
Averages at 10-20 cm
Iron Canyon II Soil MonitoringBulk Density Before & After Harvest
0.0
0.2
0.4
0.6
0.8
1.0
1.2
Undist Dist Skid
PRE-HARVEST DISTURBANCE CATEGORY
BU
LK
DE
NS
ITY
(g
/cm
3 )
PRE POST
24% of Harvest Area
Averages at 10-20 cm
Disturbance Class Matrix
Post-Harvest
Undist Dist Skid
Pre-Harvest 215 607 178 Cumulative
Undist 675 157 411 107 157 Undist
Dist 216 46 147 23 604 Dist
Skid 109 12 49 48 239 Skid
Iron Canyon II Soil MonitoringPre- vs. Post-Harvest Disturbance
Units- Feet (1000 ft total in transects)
Iron Canyon II Soil MonitoringPost-Harvest Disturbance
Bulk Density, Post-Harvest (10-20cm)
0.00
0.20
0.40
0.60
0.80
1.00
1.20
undist dist skid undist dist skid undist dist skid
UNDISTURBED DISTURBED SKID
BU
LK
DE
NS
ITY
(g
/cm
3)
POSTPRE
Iron Canyon II Soil MonitoringPost-Harvest Disturbance
Bulk Density, Post-Harvest (10-20cm)
0.00
0.20
0.40
0.60
0.80
1.00
1.20
undist dist skid undist dist skid undist dist skid
UNDISTURBED DISTURBED SKID
BU
LK
DE
NS
ITY
(g
/cm
3)
POSTPRE
7% OF HARVEST AREA
Disturbance Category: Low Mod High units
bulk density 0.89 0.94 1.01 g/cm3
Iron Canyon I Soil MonitoringLooking Back….
Averages by Disturbance Category (10-20 cm depth)
Region 5 Standard: 10% Porosity Reduction
Initial Db: 0.76
Threshold Db: 0.95
2001 UNIT - HARVESTED IN MAY
Disturbance Basics• EXTENT
% area, depth
• SEVERITYundisturbed extreme
• DISTRIBUTIONdispersed concentrated
• DURATIONshort term long term
mitigation? natural
recovery?
5 15 25 35 45 55 65 75 85 95 105 115 125 135 145 155 165 175 185 195
UNDIST DIST SKIDUNDIST DIST SKIDPRE
POST
1. Meaningful disturbance classes can be established easily and objectively
Conclusions from Iron Canyon IISoil Monitoring Results
1. Meaningful disturbance classes can be established easily and objectively
2. Pre-harvest stands came with legacy impacts that remained significant after decades
Conclusions from Iron Canyon IISoil Monitoring Results
1. Meaningful disturbance classes can be established easily and objectively
2. Pre-harvest stands came with legacy impacts that remained significant after decades
3. Legacy impacts were compounded by recent thinning, creating cumulative impacts
Conclusions from Iron Canyon IISoil Monitoring Results
1. Meaningful disturbance classes can be established easily and objectively
2. Pre-harvest stands came with legacy impacts that remained significant after decades
3. Legacy impacts were compounded by recent thinning, creating cumulative impacts
4. Assessing cumulative impacts requires pre-harvest monitoring
Conclusions from Iron Canyon IISoil Monitoring Results
5. Cumulative impacts exceed thresholds on some skid trails
Conclusions from Iron Canyon IISoil Monitoring Results
5. Cumulative impacts exceed thresholds on some skid trails
6. Old and new skid trails were coincidental at best.
Conclusions from Iron Canyon IISoil Monitoring Results
5. Cumulative impacts exceed thresholds on some skid trails
6. Old and new skid trails were coincidental at best
7. Mechanical operations on these soils will produce detrimental impacts
Conclusions from Iron Canyon IISoil Monitoring Results
5. Cumulative impacts exceed thresholds on some skid trails
6. Old and new skid trails were coincidental at best
7. Mechanical operations on these soils will produce detrimental impacts
8. The result is more areal impacts, adding to legacy disturbance for next harvest.
Conclusions from Iron Canyon IISoil Monitoring Results
National Forest Soil Scientists are Charged with Monitoring
Monitoring need not be difficult or expensive.It’s less expensive than planning & lawsuits!
THANKS TO:
Dr. Robert Powers - PSW
Brad Rust – Shasta-Trinity NF
Scott Miles – R-5