Premise
Setting up sampling designs is a non-trivial aspect to any field experiment that includes a spatial component. The sp package for R provides a simple framework for generating point sampling schemes based on region-defining features (lines or polygons) and a sampling type (regular spacing, non-aligned, random, random-stratified, hexagonal grid, etc.). The rgdal package provides a set of functions for importing/exporting common vector data formats. This example demonstrates simple import/export, iterating over sp objects, and reconstituting new objects from lists of objects. A more complex sampling scheme is demonstrated here.

• Read more

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

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

Preliminary estimation of three landscape units and associated soil series.

 
Site Description:

• Description on the US Forest Service site

 
Overview:
Description of the sampling density of completed soil survey efforts. Identification of under-sampled, critical areas (for solar-radiation modeling study), and creation of a sampling plan for spring 2007. A (nearly) design-based 'cluster random sampling' scheme (de Gruijter et al, 2006) will be used to address the main problems with collecting field samples at Pinnacles:

1. accessibility and navigation are limiting factors
2. travel time and navigation are equally problematic
3. significant gradients exist in known areas, and are of particular interest (landscape orientation and slope)