Digital Soil Mapping

Sensor installation at SJER 5-1

Submitted by dylan on Thu, 2008-05-29 23:36.
Sensor installation at SJER 5-1

EC-5 sensors installed at 10cm, 30cm, and 50cm. ECT sensors installed at 30cm and 50cm.

SJER RU 5-1 Estimated Soil Series Map

Submitted by dylan on Wed, 2008-05-14 19:20.
SJER RU 5-1 Estimated Soil Series Map

Preliminary estimation of three landscape units and associated soil series.

San Joaquin Experimental Range (SJER)

Submitted by dylan on Mon, 2008-04-07 16:08.

 
Site Description:

Finding pockets of soil between the Pinnacles

Submitted by dylan on Wed, 2006-04-26 06:38.

Using ColorBrewer to assist with thematic map color selection

Submitted by dylan on Mon, 2006-02-27 19:26.

Computing terrain-specific slope classes by region

Submitted by dylan on Sun, 2006-02-26 21:46.

 

Background

Four regions were selected within the PINN boundary for analysis of intrinsic slope classes, based on terrain type.Figure 1 illustrates the four regions that were choosen. Figure 2 shows histograms of each region along with intrinsic slope class breaks (red) and NRCS slope class breaks (gray). Note that NRCS slope classes were derived from a similar analysis (k-means clustering) of slope values from the entire park: e.g. without regard for specific landform. See attached PDF version of Figure 2 at the bottom of this page.

Sample location density: visualization examples

Submitted by dylan on Fri, 2006-02-03 03:37.

Depicting the relative density of sampling can be an interesting task, especially when the points are highly clustered and sparse. Three simple operations that can reveal subtle patterns in the spatial distribution of sample points were explored:

  • A voronoi tessellation vector operation performed on the actual sample locations.
  • A pseudo-density raster operation based on a count of cells, within proximity to sample points, and within a given radius.
  • A kernel-smoothed density function, based on a given standard deviation of spatial density.
  • A density estimation performed by the density() function from the Spatstat package in R
Sample Location Density - Voronoi
Voronoi tessellation
Sample Location Density - v.neighbors function
Psudo-density calculation
Sample Location Density - v.kernel function detail
Kernel-smoothed density

Spatial density estimation in RSpatial density estimation in R