Evaluation of pre-taxonomy soil surveys

A 1954 soil survey of Bland County, Virginia, was evaluated to determine if remapping was required to meet current soil survey standards. Considerable savings of time and money may be realized if a complete remap was not required. Ten random transects were chosen to study soil landscape units which...

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Main Author: Cowherd, William Dean
Other Authors: Agronomy
Format: Others
Language:en_US
Published: Virginia Polytechnic Institute and State University 2017
Subjects:
Online Access:http://hdl.handle.net/10919/74472
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spelling ndltd-VTETD-oai-vtechworks.lib.vt.edu-10919-744722020-09-29T05:47:38Z Evaluation of pre-taxonomy soil surveys Cowherd, William Dean Agronomy LD5655.V855 1982.C683 Soils -- Virginia -- Bland County Soils -- Sampling -- Virginia -- Bland County A 1954 soil survey of Bland County, Virginia, was evaluated to determine if remapping was required to meet current soil survey standards. Considerable savings of time and money may be realized if a complete remap was not required. Ten random transects were chosen to study soil landscape units which formed the basis for the evaluation of soil boundary placement. The soil landscape units were determined by evaluating slope, parent material, and landscape position for each traversed delineation. Based on a binomial distribution, a numerical rating was used to evaluate each delineation. Out of 89 total delineations, there were 70, 71, and 81 successful observations with respect to slope, parent material, and landscape position, respectively. Out of 10 random observations of slope, parent material, and landscape position, the probability of observing 7 or more correct observations was approximately 85, 88, and 99%, respectively. Five mapping units occurring on sideslope and/or colluvial positions were sampled according to a random effects, two-level nested analysis of variance (ANOVA) design. Physical and chemical analyses of the control section for 104 profiles were determined. All soils were described in the field and classified according to Soil Taxonomy of 1975. Variability in all mapping units with respect to cation exchange capacity (CEC), base saturation, total sand, and clay content was primarily among sites within delineations. All mapping units were composed of more than one soil. Similar soils comprised major percentages of each mapping unit. The methodology proposed by this study suggested that the Bland County soil survey could not be significantly improved upon by remapping. However, a redefinition of mapping units and redrafting onto an aerial photobase would increase its usefulness to the comparable state of many current soil surveys. Master of Science 2017-01-30T21:02:18Z 2017-01-30T21:02:18Z 1982 Thesis Text http://hdl.handle.net/10919/74472 en_US OCLC# 9178856 In Copyright http://rightsstatements.org/vocab/InC/1.0/ viii, 120, [2] leaves application/pdf application/pdf Virginia Polytechnic Institute and State University
collection NDLTD
language en_US
format Others
sources NDLTD
topic LD5655.V855 1982.C683
Soils -- Virginia -- Bland County
Soils -- Sampling -- Virginia -- Bland County
spellingShingle LD5655.V855 1982.C683
Soils -- Virginia -- Bland County
Soils -- Sampling -- Virginia -- Bland County
Cowherd, William Dean
Evaluation of pre-taxonomy soil surveys
description A 1954 soil survey of Bland County, Virginia, was evaluated to determine if remapping was required to meet current soil survey standards. Considerable savings of time and money may be realized if a complete remap was not required. Ten random transects were chosen to study soil landscape units which formed the basis for the evaluation of soil boundary placement. The soil landscape units were determined by evaluating slope, parent material, and landscape position for each traversed delineation. Based on a binomial distribution, a numerical rating was used to evaluate each delineation. Out of 89 total delineations, there were 70, 71, and 81 successful observations with respect to slope, parent material, and landscape position, respectively. Out of 10 random observations of slope, parent material, and landscape position, the probability of observing 7 or more correct observations was approximately 85, 88, and 99%, respectively. Five mapping units occurring on sideslope and/or colluvial positions were sampled according to a random effects, two-level nested analysis of variance (ANOVA) design. Physical and chemical analyses of the control section for 104 profiles were determined. All soils were described in the field and classified according to Soil Taxonomy of 1975. Variability in all mapping units with respect to cation exchange capacity (CEC), base saturation, total sand, and clay content was primarily among sites within delineations. All mapping units were composed of more than one soil. Similar soils comprised major percentages of each mapping unit. The methodology proposed by this study suggested that the Bland County soil survey could not be significantly improved upon by remapping. However, a redefinition of mapping units and redrafting onto an aerial photobase would increase its usefulness to the comparable state of many current soil surveys. === Master of Science
author2 Agronomy
author_facet Agronomy
Cowherd, William Dean
author Cowherd, William Dean
author_sort Cowherd, William Dean
title Evaluation of pre-taxonomy soil surveys
title_short Evaluation of pre-taxonomy soil surveys
title_full Evaluation of pre-taxonomy soil surveys
title_fullStr Evaluation of pre-taxonomy soil surveys
title_full_unstemmed Evaluation of pre-taxonomy soil surveys
title_sort evaluation of pre-taxonomy soil surveys
publisher Virginia Polytechnic Institute and State University
publishDate 2017
url http://hdl.handle.net/10919/74472
work_keys_str_mv AT cowherdwilliamdean evaluationofpretaxonomysoilsurveys
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