Document Type

Thesis - Open Access

Award Date


Degree Name

Master of Science (MS)

Department / School

Plant Science

First Advisor

Paul E. Fixen


One of the first great advances in agriculture came with the observation that crop production could be increased with the additions of anima manures, plant residues, and soil amendments. The study of soil fertility since then has tremendously refined those observations. Due to the advancement of soil testing, kinds and amounts of nutrients needed for a specific crop are being determined. Most fertilizer recommendations are now based on soil testing techniques performed on soil samples brought in from the field. The question now becomes: do those samples truly represent the fertility status of the field? Can the level of fertility for a 40 hectare field be determined from 2 or 3 half kilogram soil samples? If those samples are not a good representation of the field, then fertilizer recommendations based on those samp1es may actually be a disservice to the farmer. Soil sampling has been studied by many investigators for many years and this is one more endeavor in that area. The main objective of this study was to determine efficient sampling distances for estimating soil phosphorus levels of given fields. The semivariogram was used in this study to determine sampling distance. This review will be in two sections. The first deals with the different sources of variation found in soil fertility testing (Part I) while the second pertains to the semivariogram application for describing the variability of soil properties (Part II).

Library of Congress Subject Headings

Soil fertility
Soils -- Sampling -- South Dakota
Soils -- Phosphorus content -- South Dakota



Number of Pages



South Dakota State University


No Copyright - United State