中文摘要：

对宽甸盆地火山喷出物发育土壤的特性进行了研究，结果表明：火山锥顶部的土壤的土层厚度一般在90—100cm，剖面通体含有较多中等风化的气孔状玄武质火山碎屑，还保留有火山喷出物的特征。土壤偏酸性，pH（H20）介于5．18～6．78，pH（KCl）介于3．98～5．70，含有一定量的交换性酸，表层以外各发生层的pH（NaF）均大于9．4。土壤的游离铁和铁游离度较高，多数剖面B层具有铁质特性，活性铁含量的变幅较大，铁活化度较高；硅铝率（Sa）、硅铁铝率（Saf）和风化淋溶系数（ba）较高，CIA指数较小，土壤发育较弱；多数土层的土壤有机碳含量、磷酸盐吸持量、草酸铵浸提Al＋1／2Fe、土壤2～0．02mm粒级含量等主要鉴定指标已符合火山灰特性的鉴定标准，最终能否确认其具有火山灰特性还有待进一步鉴定火山玻璃含量。台地上的土壤，其土体中可以发现极少量强风化的气孔状火山碎屑，土壤的游离铁和铁游离度较高，土壤B层具有铁质特性，活性铁含量的变幅较大，铁活化度较高，硅铝率（sa）、硅铁铝率（saf）和风化淋溶系数（ba）较低，CIA指数较大，土壤发育较强，土壤2～0．02mm粒级含量〈300gkg-1，不具有火山灰特性。

英文摘要：

The characteristics of soils developed on volcanic ejecta in Kuandian basin were studied. The results showed that the depth of the soil on the top of volcanic cone was between 90 and 100 cm in general, and there were much vesicular tephra which weathered moderately in the soil and still retained volcanic ejecta characteristics. The soils were slightly acidic because pH （H20） were from 5.18 to 6.78 and contained a certain amount of exchange acid due to pH （KC1） were 3.98 to 5.70, soil pH （NaF） were greater than 9.4 except A-horizons. The ratios of Fed and Fed/Fet were relatively high, most profiles of B horizon were characteristic of ferric property. Feo content varied greatly, and Feo/Fed ratios were relatively high. The values of Sa, Saf and ba were relatively high, and the index of CIA was relatively low, which indicated that these soils developed relatively weak. Some main indicators for diagnosing andic soil properties, such as the contents of organic carbon, phosphate retention, AI＋I/2Fe （extracted by ammonium oxalate） and the fine-earth fraction （0.02 to 2.0 mm in size） in many soil horizons, had reached the identification standards. However, to make sure that these soils had andic soil properties or not, the content of volcanic glass need to be analyzed. There was a minute quantity of vesicular tephra which weathered strongly in the soil developed at lava plateau, and the values of Fed and Fed/Fet were much greater, and the profiles of B horizon showed ferric property, and Feo had a greater amplitude, and Feo/Fed was higher, and the values of Sa, Saf and ba were lower. The index of CIA was higher, which indicated that the soil developed relatively strongly. The soil did not meet the criteria of andic soil because the contents of fine-earth fraction （0.02 to 2.0 mm in size） were less than 300 g kg-1.