Just back from the annual meetings, and it looks like there is a significant interest in collaborative R coding of soils-related algorithms and visualization. A new R-forge site has been created to host Algorithms for Quantitative Pedology. Public release of the 'soil' package should be ready in a couple weeks.

Soil Profile Dendrogram

• Soil Survey in National Parks
• Upscaling and Downscaling Soil Survey

Mean %C distribution with depth, with std. deviation, discretized to 1-cm intervals.

Depth profiles of percent carbon in some of the pedons from Lewis watershed.

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

depth-function aggregated mean +- 1 standard deviation

linear model (piece-wise splines), conditioned by clay content, fit + 95% CI

linear model (piece-wise splines) fit + 95% CI