Diagnostic Subsurface- Below the Surface Argillic horizon(淀积粘化层): The argillic is a horizon that accumulates clay that has translocated from above the clays are found as coatings or clay skins on the surface of peds. The bt horizon identifies the argillic horizon The soil above with the ochric epipedon has an argillic horizon at the Bt Natric Horizon(pA): The natric horizon is like the argillic with the addition that sodium has accumulated also to where there is >15% exchangeable sodium The horizon will also have columnar soil structure in the btn Kandic horizon(铁铝淀积层): The kandic horizon has an accumulation offe and al oxides as well as kaolinite clays. Clays skins do not need to be evident. The low activity of the clay is shown by the low cation- holding capacities (<16 meq/100g). These horizons form in areas of intense weathering. Oxic horizon(氧化层): the oxic horizon is a highly weathered subsurface horizon that is very high in Fe and Al oxides. The soil only has 10% weatherable minerals in the fine fraction all the other minerals have weathered to elements lt is found in mostly in humid tropical and subtropical regions and is designated as the bo horizon
Diagnostic Subsurface- Below the Surface Argillic Horizon（淀积粘化层）: The argillic is a horizon that accumulates clay that has translocated from above. The clays are found as coatings or clay skins on the surface of peds. The Bt horizon identifies the argillic horizon. The soil above with the ochric epipedon has an argillic horizon at the Bt. Natric Horizon（碱化层）: The natric horizon is like the argillic with the addition that sodium has accumulated also to where there is > 15 % exchangeable sodium. The horizon will also have columnar soil structure in the Btn. Kandic Horizon（铁铝淀积层）: The kandic horizon has an accumulation of Fe and Al oxides as well as kaolinite clays. Clays skins do not need to be evident. The low activity of the clay is shown by the low cation-holding capacities ( < 16 meq/100g) . These horizons form in areas of intense weathering. Oxic Horizon（氧化层）: the oxic horizon is a highly weathered subsurface horizon that is very high in Fe and Al oxides. The soil only has 10% weatherable minerals in the fine fraction, all the other minerals have weathered to elements. It is found in mostly in humid tropical and subtropical regions and is designated as the Bo horizon
Diagnostic Subsurface- Below the Surface Spodic horizon(灰化淀积层): The spodic horizon is an illuvial horizon characterized by the accumulation of colloidal organic matter. aluminum oxide and iron. It is commonly found in highly leached forest soils of cool humid climate, on sandy parent materials and is given the bhs, or Bs horizon designation Albic Horizon (tAZ): The albic horizon is a light coloredeluvial horizon that is low in clay and other oxides which have been removed by leaching(e horizon) The color of the horizon is the often white or light tan where these horizons finger down into the argillic the diagnostic feature of Glossic is identified Calcic horizon(钙积层): The calcic horizon is an illuvial accumulation of carbonates(mostly CaCO3). The carbonates will react with HCi giving off CO2 or bubbles They are white chalk-like nodules or filaments The calcic horizon will be identified in the profile as the bk horizon Cambic Horizon (SEE): The cambic horizon is a slightly altered layer that has not undergone enough illuviation to become argillic Cambic horizons have developed different color or structure from what the parent material(C horizon)had before pedogenesis. The Bw horizon designation is used for the cambic horizon
Diagnostic Subsurface- Below the Surface Spodic Horizon （灰化淀积层）:The spodic horizon is an illuvial horizon characterized by the accumulation of colloidal organic matter, aluminum oxide and iron. It is commonly found in highly leached forest soils of cool humid climate, on sandy parent materials and is given the Bhs, or Bs horizon designation. Albic Horizon（漂白层）: The albic horizon is a light colored eluvial horizon that is low in clay and other oxides which have been removed by leaching ( E horizon). The color of the horizon is the often white or light tan. Where these horizons finger down into the argillic the diagnostic feature of Glossic is identified. Calcic Horizon（钙积层）: The calcic horizon is an illuvial accumulation of carbonates (mostly CaCO3). The carbonates will react with HCl giving off CO2 or bubbles. They are white chalk-like nodules or filaments. The Calcic horizon will be identified in the profile as the Bk horizon Cambic Horizon（雏形层）:The cambic horizon is a slightly altered layer that has not undergone enough illuviation to become argillic. Cambic horizons have developed different color or structure from what the parent material (C horizon) had before pedogenesis. The Bw horizon designation is used for the cambic horizon
Natric Horizon Barnes A Cam bi B aibi Horizon Bk lumna Calcic Structure bck WALLA C The Epipedon Oxic horizon Cured basalt MOLOKA
四、中国土壤系统分类 分类原则 中国土壤糸统分类为多级分类,共六级,即土纲、亚纲、土类 土族和土糸。前四级为高级分类级别,后三级为基层分类级别。 分类糸统和命名方法 该分类糸统已初步拟出了土纲、正纲、土类和正类检索表,共把全国分为14个 土纲、39个亚纲、141土类和595亚类。 中国土壤糸统分类也是一个检索性分类,其各级类别是通过诊新层和诊新特性 按表114顺序,自上而下逐一排除那些不能符合某种土壤要求的类别,找出其正确 的分类位置 中国土壤糸统分类在命名土壤单元肘采用了在土纲、亚纲、土类、亚类为一段 的连续命名法,在此基础上加颗粒大小级别、矿物组成、土壤温度状况等,构成土 族名称,而其下的土糸则另一列段,单独命名。名称结构以土纲名称为基础,其前 叠加反映土纲、土类和正类的性质术语,以分别构成正纲、土类和亚类的名称。性 质的术语尽量限制为2个汉字,这样土纲名称一般为3个汉字,正纲为5个汉字,土 类为7个汉字,正类为9个汉字
四、中国土壤系统分类 分类原则 中国土壤系统分类为多级分类，共六级，即土纲、亚纲、土类、 土族和土系。前四级为高级分类级别，后三级为基层分类级别。 分类系统和命名方法 该分类系统已初步拟出了土纲、亚纲、土类和亚类检索表，共把全国分为14个 土纲、39个亚纲、141土类和595亚类。 中国土壤系统分类也是一个检索性分类，其各级类别是通过诊断层和诊断特性 按表11.4顺序，自上而下逐一排除那些不能符合某种土壤要求的类别，找出其正确 的分类位置。 中国土壤系统分类在命名土壤单元时采用了在土纲、亚纲、土类、亚类为一段 的连续命名法，在此基础上加颗粒大小级别、矿物组成、土壤温度状况等，构成土 族名称，而其下的土系则另一列段，单独命名。名称结构以土纲名称为基础，其前 叠加反映土纲、土类和亚类的性质术语，以分别构成亚纲、土类和亚类的名称。性 质的术语尽量限制为2个汉字，这样土纲名称一般为3个汉字，亚纲为5个汉字，土 类为7个汉字，亚类为9个汉字
五中国土壤分布规律 地带性分布规律(zoη hality)土壤类型在空间的规律性分布称为 土壤分布的地带性。 (-)水手地带丝纬度地带性:按照纬废呈有规律分布 Horizontal soil zonality 经度地带性:按照经度呈有规律分布 (二)垂直地带性( vertical zonality):按照海拔高度有规律的分布 特征。 (三)土壤区堿地带性:在土壤纬度区堿内,按照地形、地质、水 文等自然条件不同。呈现规律性分布。 显堿土( Zonal so):在一定生物气候带、深受气候、植被等地带形成 土因素影响而形戍的地带性土壤。如红壤、黄壤、棕壤。 隐域土( intrazonal soil)地形、母质、地下水等区域性因素超越气 候、植被等地带性成土因素而形成的土壤,沼译土、盐土、碱土 石灰岩土 泛堿土( azonal soil)分布于任何地带,非地带性土壤(水稻土 冲积土)
五.中国土壤分布规律 一.地带性分布规律（zonality）土壤类型在空间的规律性分布称为 土壤分布的地带性。 （一)水平地带性 Horizontal soil zonality （二）垂直地带性（vertical zonality）：按照海拔高度有规律的分布 特征。 （三）土壤区域地带性：在土壤纬度区域内，按照地形、地质、水 文等自然条件不同。呈现规律性分布。 显域土(Zonal soil):在一定生物气候带、深受气候、植被等地带形成 土因素影响而形成的地带性土壤。如红壤、黄壤、棕壤。 隐域土（intrazonal soil）地形、母质、地下水等区域性因素超越气 候、植被等地带性成土因素而形成的土壤，沼泽土、盐土、碱土、 石灰岩土。 泛域土（azonal soil）分布于任何地带，非地带性土壤（水稻土、 冲积土） 纬度地带性：按照纬度呈有规律分布 经度地带性：按照经度呈有规律分布