中文摘要：

以长白山、龙岗、宽甸火山喷出物发育土壤为研究对象，对供试土壤形态特征进行描述，并对其pH、有机碳、磷酸盐吸持量、铁铝氧化物、火山玻璃等性质进行测定，按照《中国土壤系统分类检索（第三版）》的原则和方法并结合美国《土壤系统分类检索》第11版，讨论了土壤的诊断层、诊断特性，并进行了分类检索。结果表明：火山喷出物发育的土壤未必就是火山灰土。长白山天池火山锥顶部的土壤发育程度极弱，属于新成土；天池火山锥底部的土壤已经形成土壤结构体，且具有火山灰特性，属于火山灰土；宽甸青椅山顶部土壤以及龙岗金龙顶子底部土壤均具有火山灰特性，检索为火山灰土；宽甸大川头底部土壤0．02～2mm粒级含量未达到火山灰特性的要求，但具有雏形层，检索为雏形土。

英文摘要：

Soils developed from volcano ejecta in Changbai, Longgang and Kuandian were studied for description of morphological properties of the soils and for determination of pH, organic carbon, phosphate retention, iron-aluminium ox- ides and volcanic glass. Besides, diagnostic horizons, diagnostic characteristics and taxonomy of the soils were discussed in reference to according to the principles and methods of the ＂ Keys to Chinese Soil Taxonomy （3rd ed） and the ＂Keys to US Soil Taxonomy （The USA llth ed）＂ Results show that soils developed from volcano ejecta should not necessarily be classified as Andosols. The soil on the top of the volcanic cone, Tianchi of the Changbai mountain is poorly developed and should be classified as Primosols, while the soil at the foot of the cone is well-structured and characterized by volcanic ash and hence should be classified as Andosols. The soils on top of the Qingyi mountain in Kuandian and at the foot of the Longgang maintain all display features of volcanic ash and should be classified as Andosols. The soil at the foot of the Da- chuantou maintain in Kuandian falls short of the index of volcanic ash in content of 0.02 - 2 mm particles, but it displays a clear Cambic horizon, so it should be classified as Cambosols,