Soil Collection

  • Typic Hapludults
    Tropical humid paddy soils with plinthite.
    Taoyuan, Taiwan
    Typic Hapludults
    Detailed Descriptions

    This soil profile showed coarse Fe—Mn nodules between the depth of 50—65 cm. The upper layer exhibited fine platy structure due to periodic wetting and drying. Fe—Mn nodules reflect clear evidence of soil chemistry; that is, Mn always moved faster than Fe during flooding due to its higher redox potential.

    Taoyuan, Taiwan detail 1
    Taoyuan, Taiwan detail 2
  • Hapludands
    Temperate humid volcanic soils.
    Hokkaido, Japan
    Hapludands
  • Udifluvents
    Temperate humid alluvial soils.
    Hokkaido, Japan
    Udifluvents
  • Melanaquands
    Temperate humid volcanic soils.
    Hokkaido, Japan
    Melanaquands
    Detailed Descriptions

    Under reducing conditions, iron is released from minerals; the ferrous ions are oxidized at the root channels into orange ferric iron, forming lepidocrocite.

    Hokkaido, Japan detail 1
  • Udifluvents
    Temperate alluvial/colluvial soils (grape garden).
    Hokkaido, Japan
    Udifluvents
  • Hapludands
    Temperate humid volcanic soils (grape garden).
    Hokkaido, Japan
    Hapludands
  • Hapludands
    Temperate humid volcanic soils (chinese yam).
    Hokkaido, Japan
    Hapludands
  • Udorthents
    Temperate humid forest soils with well drainage.
    Hokkaido, Japan
    Udorthents
  • Humaquepts
    Temperate humid forest soils with poor drainage.
    Hokkaido, Japan
    Humaquepts
    Detailed Descriptions

    Poor drainage in the upper layer causes reduced manganese to migrate downward, and upon contact with oxygen it forms black manganese oxides.

    Hokkaido, Japan detail 1
    Hokkaido, Japan detail 2
  • Hydraquents
    Temperate humid paddy soils.
    Hokkaido, Japan
    Hydraquents
  • Typic Haplustalfs
    Tropical humid basaltic soils.
    Penghu, Taiwan
    Typic Haplustalfs