gilgais                 package:MASS                 R Documentation

Line Transect of Soil in Gilgai Territory

Description:

     This dataset was collected on a line transect survey in gilgai
     territory in New South Wales, Australia.  Gilgais are natural
     gentle depressions in otherwise flat land, and sometimes seem to
     be regularly distributed. The data collection was stimulated by
     the question: are these patterns reflected in soil properties?  At
     each of 365 sampling locations on a linear grid of 4 meters
     spacing, samples were taken at depths 0-10 cm, 30-40 cm and 80-90
     cm below the surface. pH, electrical conductivity and chloride
     content were measured on a 1:5 soil:water extract from each
     sample.

Usage:

     gilgais

Format:

     This data frame contains the following columns:

     'pH00' pH at depth 0-10 cm.

     'pH30' pH at depth 30-40 cm.

     'pH80' pH at depth 80-90 cm.

     'e00' electrical conductivity in mS/cm  (0-10 cm).

     'e30' electrical conductivity in mS/cm (30-40 cm).

     'e80' electrical conductivity in mS/cm (80-90 cm).

     'c00' chloride content in ppm  (0-10 cm).

     'c30' chloride content in ppm (30-40 cm).

     'c80' chloride content in ppm (80-90 cm).


Source:

     Webster, R. (1977) Spectral analysis of gilgai soil. _Australian
     Journal of Soil Research_ *15*, 191-204.

     Laslett, G. M. (1989) Kriging and splines: An empirical comparison
     of their predictive performance in some applications (with
     discussion). _Journal of the American Statistical Association_
     *89*, 319-409

References:

     Venables, W. N. and Ripley, B. D. (2002) _Modern Applied
     Statistics with S._ Fourth edition.  Springer.

