Soil Moisture in the Tromble Watershed from 6/2010 to 10/2011

Study number: 

338

Data set ID: 

210338004

Data Access: 

Unrestricted

Dataset status: 

Date range: 

2010-06-06 to 2011-09-30

Original investigator: 

Ryan Templeton

Methods: 

Methods of recording:

INSTRUMENTAL

Methodology:

Half-hourly averaged soil moisture datasets obtained from Hydraprobe measurements were transformed to volumetric soil moisture (m3/m3) values via the ‘loam soil’ type factory calibration equation to coincide with the dominant soil type found in the Tromble watershed (see the soil analysis appendix).  For all analyses, periods of interrupted measurements for individual probes resulted in either removal of periods of compromised data from the dataset entirely, or removal of the individual probe data entirely for the period of analysis.  In order to calculate spatially averaged soil moisture, the watershed was separated via the main channel network into 3 sections:  the north-facing slope, the south-facing slope, and the west-facing slope.  Each slope was separated into 5 bins based on elevation.  Elevation weighted soil moisture was then calculated for each slope at the three sampled depths with each of the 5 transect soil moisture locations corresponding to one of the 5 elevation bins.  Watershed averaged soil moisture was then calculated at each depth by the area-weighted average of slope soil moisture using the equation below: 

θ_avg=(1448*SM1+1121*SM2+1232*SM3+1348*SM4+15911*SM5+2850*SM6+1086*SM7+1312*SM8+

1278*SM9+9193*SM10+997*SM11+535*SM12+624*SM13+865*SM14+6891*SM15)/46691

Finally, profile averaged soil moisture was calculated by treating the measured 5cm soil moisture as average soil moisture over the top 10 cm of soil, measured 15 cm soil moisture was treated as the average soil moisture over the depth of 10-20 cm, and measured 30 cm soil moisture was treated as the average soil moisture over the depth of 20-40 cm.

θ_profile=(10*θ_5cm+10*θ_15cm+20*θ_30cm )/40

 

Quality assurance: 

Much of this is covered in the processing section, but in addition to the steps already taken, graphical analysis was also performed

Additional information: 

 Below I supply a map and table of relative and absolute equipment locations for all equipment installed within the sampling region.  UTM coordinates given are in WGS84 13N.  Each soil moisture probe location has 3 sampling depths of 5 cm, 15 cm, and 30 cm for a total of 44 sensors ( a 30 cm depth soil moisture probe was not installed at SM6).  The soil moisture dataset includes measurements taken at soil sampling (SM1-SM15) locations.

Sensor Type

ID

Northing [m]

Easting [m]

Elevation [m]

Soil Probe

SM1

3606431.753

349156.521

1453.61

 

SM2

3606418.716

349154.273

1454.85

 

SM3

3606406.579

349153.374

1455.85

 

SM4

3606396.690

349152.025

1456.82

 

SM5

3606384.103

349148.879

1457.34

 

SM6

3606461.421

349205.968

1456.04

 

SM7

3606471.311

349208.665

1456.88

 

SM8

3606482.998

349211.363

1457.64

 

SM9

3606494.686

349214.959

1458.62

 

SM10

3606507.273

349214.959

1459.04

 

SM11

3606437.596

349356.559

1462.21

 

SM12

3606432.202

349365.999

1462.89

 

SM13

3606428.156

349377.686

1463.66

 

SM14

3606421.414

349388.924

1464.36

 

SM15

3606417.817

349400.163

1465.02

Rain gauge

R1

3606454.229

349126.402

1452.51

 

R2

3606407.928

349150.227

1455.80

 

R3

3606483.448

349214.509

1457.77

 

R4

3606425.459

349377.237

1463.61

 

R5

3606414.671

349530.974

1469.47

Flumes

F1

3606455.577

349126.852

1452.52

 

F2

3606441.642

349149.328

1453.00

 

F3

3606444.339

349219.004

1455.00

 

F4

3606451.082

349328.239

1459.61

Tower

T

3606407.793

349528.844

1469.40

 

Maintenance: 

Every 30 minute

Long-term dataset: 

Signature dataset: 

LTER Core Area(s): 

Data category: 

LTER VI Proposal Category: 

Research Network: