Doha Zeadeh Master Horizons and Layers Quiz

Slightly decomposed organic material = Used with O horizons with a rubbed fiber content of 40% or more by volume Intermediate decomposition = Used with O horizons with rubbed fiber content of 17 to 40% by volume Highly decomposed organic material = Used with the O master horizon with a rubbed fiber content of less than 17% by volume Tillage or other cultivation disturbance = Plowed organic soil material

Slightly decomposed organic material = Used with A horizons with a rubbed fiber content of 40% or more by volume Intermediate decomposition = Used with A horizons with rubbed fiber content of 17 to 40% by volume Highly decomposed organic material = Used with the A master horizon with a rubbed fiber content of less than 17% by volume Tillage or other cultivation disturbance = Plowed organic soil material

Coprogenous earth = A limnic layer of coprogenous earth. Used only with L Diatomaceous earth = A limnic layer of diatomaceous earth. Used only with L Marl = Indicates a limnic layer of marl. Used only with L Highly decomposed organic material = Used with the L master horizon with a rubbed fiber content of less than 17% by volume

<p>f = Frozen soil or water ff = Dry permafrost ss = Presence of slickensides u = Presence of human-manufactured materials (artifacts)</p> Signup and view all the answers

<p>n = Accumulation of exchangeable sodium t = Usually used in B horizons b = Indicates a buried horizon g = Indicates strongly gleyed horizons with dominant colors</p> Signup and view all the answers

<p>Indicates a horizon that is continually colder than 0°C and not cemented by ice. = ff Formed by shear failure as clay minerals swell upon wetting. = ss Used for horizons or layers containing permanent ice. = f Presence of processed wood products, bricks, glass, asphalt, and plastic. = u</p> Signup and view all the answers

<p>Used in any master horizon to indicate an accumulation of exchangeable sodium. = n Indicates a buried mineral soil horizon. = b Not used in materials with low chroma and no evidence of saturation or wetness history. = g Usually used in B horizons but may be used in C and R layers. = t</p> Signup and view all the answers

<p>Tillage or other cultivation disturbance = Used with A mineral horizon, even if the materials mixed by the cultivation are from an E, B, or C horizon Accumulation of silicate clay = Indicates accumulation of clay, either formed within the horizon and subsequently moved within the horizon or moved by illuviation into the horizon Development of color and structure = Used with B horizons that have developed color, usually redder than the A or C materials, or soil structure, but do not have apparent illuvial accumulations Engulfment of horizon by secondary carbonates = Used with B horizons when the horizon fabric is plugged with pedogenic calcium carbonate (50% or more by volume)</p> Signup and view all the answers

<p>Tillage or other cultivation disturbance = Used with A mineral horizon, even if the materials mixed by the cultivation are from an E, B, or C horizon Accumulation of silicate clay = Indicates accumulation of clay, either formed within the horizon and subsequently moved within the horizon or moved by illuviation into the horizon Development of color and structure = This symbol is used with B horizons that have developed color, usually redder than the A or C materials, or soil structure, but do not have apparent illuvial accumulations Illuvial accumulation of amorphous, dispersible organic matter-sesquioxide complexes = The sesquioxides are dominated by aluminum but are present in very small quantities</p> Signup and view all the answers

<p>Tillage or other cultivation disturbance = Used with A mineral horizon, even if the materials mixed by the cultivation are from an E, B, or C horizon Accumulation of silicate clay = Indicates accumulation of clay, either formed within the horizon and subsequently moved within the horizon or moved by illuviation into the horizon Development of color and structure = This symbol is used with B horizons that have developed color, usually redder than the A or C materials, or soil structure, but do not have apparent illuvial accumulations Illuvial accumulation of amorphous, dispersible organic matter-sesquioxide complexes = The sesquioxides are dominated by aluminum but are present in very small quantities</p> Signup and view all the answers

<p>Tillage or other cultivation disturbance = Used with A mineral horizon, even if the materials mixed by the cultivation are from an E, B, or C horizon Accumulation of silicate clay = Indicates accumulation of clay, either formed within the horizon and subsequently moved within the horizon or moved by illuviation into the horizon Development of color and structure = This symbol is used with B horizons that have developed color, usually redder than the A or C materials, or soil structure, but do not have apparent illuvial accumulations Illuvial accumulation of amorphous, dispersible organic matter-sesquioxide complexes = The sesquioxides are dominated by aluminum but are present in very small quantities</p> Signup and view all the answers

<p>Tillage or other cultivation disturbance = Used with A mineral horizon, even if the materials mixed by the cultivation are from an E, B, or C horizon Accumulation of silicate clay = Indicates accumulation of clay, either formed within the horizon and subsequently moved within the horizon or moved by illuviation into the horizon Development of color and structure = This symbol is used with B horizons that have developed color, usually redder than the A or C materials, or soil structure, but do not have apparent illuvial accumulations Illuvial accumulation of amorphous, dispersible organic matter-sesquioxide complexes = The sesquioxides are dominated by aluminum but are present in very small quantities</p> Signup and view all the answers

<p>Tillage or other cultivation disturbance = Used with A mineral horizon, even if the materials mixed by the cultivation are from an E, B, or C horizon Accumulation of silicate clay = Indicates accumulation of clay, either formed within the horizon and subsequently moved within the horizon or moved by illuviation into the horizon Development of color and structure = This symbol is used with B horizons that have developed color, usually redder than the A or C materials, or soil structure, but do not have apparent illuvial accumulations Illuvial accumulation of amorphous, dispersible organic matter-sesquioxide complexes = The sesquioxides are dominated by aluminum but are present in very small quantities</p> Signup and view all the answers