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    <r:URN>urn:ddi:se.researchdata:doi-10-17045-sthlmuni-5173477.ResourcePackage:2.0</r:URN>
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              <r:String>Mats Widgren</r:String>
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        <r:String xml:lang="en">A map of agricultural systems in Africa by 1800</r:String>
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          <r:String xml:lang="sv">Stockholms universitet</r:String>
          <r:String xml:lang="en">Stockholm University</r:String>
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      </r:Publisher>
      <r:Publisher>
        <r:PublisherName>
          <r:String xml:lang="sv">Stockholms universitet</r:String>
          <r:String xml:lang="en">Stockholm University</r:String>
        </r:PublisherName>
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      <r:PublicationDate>
        <r:SimpleDate>2017-07-05</r:SimpleDate>
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    <r:Abstract>
      <r:Content xml:lang="en">Illustrations, maps and GIS-files of the following article

Widgren Mats:  Agriculture in sub-Saharan Africa by 1800: a map and a gazetteer. In Mercuri, A.M., D'Andrea, A.C., Fornaciari, R., Höhn, A. (eds.): Plants and People in the African Past - Progress in African Archaeobotany (in press), SPRINGER 

The GIS-files can be opened with GIS programmes such as QGIS (open source) or ArcGIS. Note that they have to overlayered with coastlines (and lakes, depending on scale).

If you use the data: please refer to the article.

Abstract

Recent global
historical cropland modelling grossly underestimates the pre-colonial
development of agriculture in the Americas and many parts of sub-Saharan
Africa. Such models are usually developed from backcasting from recent land
cover combined with environmentally deterministic algorithms. Historical
geographers have been slow in responding to this new demand for a global
synthesis. Here a a
preliminary map of African agricultural systems by 1800 AD is presented. It
forms part of the project Mapping Global Agriculture and is based on the
existing historical literature, observations by early travellers, archaeology
and archaeobotany. Its preliminary nature must be emphasized.</r:Content>
    </r:Abstract>
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        <r:URN>urn:ddi:se.researchdata:doi-10-17045-sthlmuni-5173477.TopicalCoverage:2.0</r:URN>
        <r:Subject xml:lang="en" controlledVocabularyID="10507" controlledVocabularyName="Standard för svensk indelning av forskningsämnen 2025">Physical Geography</r:Subject>
        <r:Subject xml:lang="sv" controlledVocabularyID="10507" controlledVocabularyName="Standard för svensk indelning av forskningsämnen 2025">Naturgeografi</r:Subject>
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