rdf-syntax-grammar
mods:
  schema location: http://www.loc.gov/mods/v3 http://www.loc.gov/standards/mods/v3/mods-3-2.xsd
  title info:
    non sort: A
    title: study of two toposequences of the dry valley systems of western Niger (West Africa)
  name:
    name part: Ouattara, Mamadou
    name part: 1949-
    role:
      role term: creator
  name:
    name part: Hallmark, C. Tom
    role:
      role term: degree committee member.
  name:
    name part: Hossner, Lloyd R.
    role:
      role term: degree committee member.
  name:
    name part: Smeins, Fred E.
    role:
      role term: degree committee member.
  name:
    name part: Wilding, Larry P.
    role:
      role term: degree supervisor.
  name:
    name part: Texas A & M University
    role:
      role term: degree granting institution.
  type of resource: text
  genre: bibliography
  genre: Academic theses.
  genre: Classification.
  origin info:
    place:
      place term: xx
    date issued: 1990
    issuance: monographic
  language:
    language term: eng
  physical description:
    form: print
    extent: xxi, 293 leaves : illustrations ; 29 cm
  abstract: Relationship between landscape position and soil characteristics such as moisture regime, phosphorus fixing capacity, and acidity were investigated on two toposequences of western Niger (West Africa). The toposequences studied overly the Continental Terminal geologic deposits and have different mean annual rainfall (Hamdallaye, 550 mm; Malgorou, 750 mm). A survey of local farmers on land management and land degradation was also conducted at both sites. At the Hamdallaye toposequence, soils are formed on deep eolian mantle, are sandy and were classified as Ustipsamments and Kandiustalfs. At the Malgorou toposequence, soils are generally formed on Continental Terminal residuum; they are loamy in texture, shallow, and gravelly at depth. Soils at Malgorou were classified as Kandiustalfs and Kanhaplustalfs. Characteristics common to soils of both toposequences are low organic matter, low ECEC and a pH moderately to strongly acid. The standard P requirement (SPR) of soils was very low at Hamdallaye and low at Malgorou. No trend in P sorption was observed along the toposequence at Hamdallaye; at Malgorou an increase in P sorption was observed down the slope in a segment of the toposequence. The P sorption increased about 2.5 fold from surface to the upper sub-horizons at both toposequences. SPR values appear to be highly correlated with soil characteristics at the two sites. There was no simple relationship between soil moisture availability and topographic position at either toposequences; main factors controlling moisture availability were surface texture, crusting and evapotranspiration. Soil Taxonomy placements of soil moisture regime are ustic at Hamdallaye and marginally ustic to aridic at Malgorou. The survey of local farmers at Hamdallaye indicated that landscape position is not the major factor for land use at Hamdallaye; at Malgorou, farmers plant different crops depending on landscape position and type of soil. The survey also indicated that important degradatio…
  note: "Major subject: Soil science."
  note: Typescript (photocopy).
  note: Vita.
  note: Ph. D. Texas A & M University 1990
  note: Includes bibliographical references.
  subject:
    geographic code: f-ng---
  subject:
    topic: Soil moisture
    geographic: Nigeria, Western
  subject:
    topic: Soils
    topic: Phosphorus content
    geographic: Nigeria, Western
  subject:
    topic: Soils
    geographic: Nigeria, Western
    genre: Classification
  subject:
    topic: Major soil science
  subject:
    topic: Soil moisture
  subject:
    topic: Soils
  subject:
    topic: Soils
    topic: Phosphorus content
  subject:
    geographic: Nigeria, Western
  identifier: http://gateway.proquest.com/openurl
  identifier: https://hdl.handle.net/1969.1/DISSERTATIONS-1163156
  identifier: http://proxy.library.tamu.edu/login
  related item:
    location:
      url: http://gateway.proquest.com/openurl
  related item:
    location:
      url: https://hdl.handle.net/1969.1/DISSERTATIONS-1163156
  related item:
    location:
      url: http://proxy.library.tamu.edu/login
  record info:
    record content source: TXA
    record creation date: 910516
    record change date: 20220103134839.0
    record identifier: in00001008725
    language of cataloging:
      language term: eng