Visualization of Soil Properties
Submitted by vbullard on Fri, 2009-06-12 17:04.
Submitted by dylan on Thu, 2008-11-06 00:27.
 Mean %C distribution with depth, with std. deviation, discretized to 1-cm intervals.
Submitted by dylan on Thu, 2008-11-06 00:25.
 Depth profiles of percent carbon in some of the pedons from Lewis watershed.
Submitted by dylan on Mon, 2008-10-27 16:08.
 Decagon Sensors: EC-5 (moisture) and ECT (temperature)
Premise
Simple demonstration of working with time-series data collected from Decagon Devices soil moisture and temperature sensors. These sensors were installed in a potted plant, that was semi-regularly watered, and data were collected for about 80 days on an hourly basis. Several basic operations in R are demonstrated:
- reading raw data in CSV format
- converting date-time values to R's date-time format
- applying a calibration curve to raw sensor values
- initialization of R time series objects
- seasonal decomposition of additive time series (trend extraction)
- plotting of decomposed time series, ACF, and cross-ACF
Submitted by dylan on Mon, 2008-10-27 02:13.
Submitted by dylan on Wed, 2008-10-01 23:48.
 depth-function aggregated mean +- 1 standard deviation
Submitted by dylan on Wed, 2008-10-01 23:46.
 linear model (piece-wise splines), conditioned by clay content, fit + 95% CI
Submitted by dylan on Wed, 2008-10-01 23:43.
 linear model (piece-wise splines) fit + 95% CI
Submitted by dylan on Mon, 2007-12-03 06:51.
Examples with Some Real Data
Notes:
- See attached files at bottom of page
Submitted by dylan on Thu, 2007-09-27 17:36.
Premise
Soil color generally varies in a predictable pattern with depth according to surface vegetation, clay mineralogy and parent material. Highly contrasting parent geology influences soil color within Pinnacles via four main processes:
- Original color of parent material
sedimentary sources: grey, yellow, white
granitic sources: yellow to orange
volcanic sources: pink, orange, white, green
- Landscape age
older landscapes generally have redder hues (Fe-expression) from longer chemical weathering
- Particle size distribution of parent material and the resulting field capacity of a soil formed from it
coarse textures result in lower field capacities, limiting vegetation growth and subsequent accumulation of organic matter in the surface horizons
- Weathering rate of parent material
sedimentary materials derived from granitic sources (grey to yellow hues) have high levels of quartz and are therefore less susceptible to chemical weathering than volcanic rocks (redder hues)
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