长白山脉火山碎屑物发育土壤特性研究

Properties of Soils Developed from Volcanic Tephra in Changbai Mountain

以吉林省长白山天池火山锥和辽宁省宽甸县黄椅山火山锥上火山碎屑物发育的土壤为研究对象,按照中国科学院南京土壤研究所主编的《土壤调查实验室分析方法》,探索火山碎屑物发育土壤的形态学、化学和矿物学特性。研究结果表明,供试土壤pH（H2O）值介于5.32-6.47,pH（KCl）值介于4.15-5.73,pH（NaF）值介于8.40-10.55;表层有机碳含量介于31.51-59.48g/kg之间;磷酸盐吸持量介于7.08%-75.89%之间;阳离子交换量（CEC7）介于2.35-39.90cmol（＋）/kg;交换性盐基以Ca^2＋、Mg^2＋为主;盐基饱和度为15.33%-55.68%;连二亚硫酸钠-柠檬酸钠-碳酸氢钠（DCB）、酸性草酸铵和焦磷酸钠浸提的铝、铁值分别表现为Alp〈Ald〈Alo,Fep〈Feo〈Fed;水铝英石含量介于0.73%-9.05%,水铁矿含量介于0.46%-4.86%。4个土壤剖面相比较,天池火山锥土壤的发育程度低于宽甸火山锥的土壤;同一火山锥,锥上部土壤的发育程度弱于锥下部的土壤。研究表明：火山碎屑物发育的土壤不同于其他一般母质发育的土壤,水铝英石等无定形矿物的存在导致土壤的Alo值大于Ald值;土壤的pH（NaF）和磷酸盐吸持量与土壤中水铝英石含量呈极显著的正相关,所以,可以通过测定土壤中的pH（NaF）、磷酸盐吸持量预测供试样品的水铝英石含量。

The thesis investigated the morphological,chemical and mineralogical properties of the soils developed from volcanic tephra on volcanic cones located in Tianchi,Changbai mountain of Jilin province and Huangyi mountain in Kuandian country of Liaoning province.The methods used were described in detail in the Soil Survey Laboratory Methods,which were written by Institute of Soil Science,Chinese Academy of Sciences.Results showed that,the values of pH（H2O）,pH（KCl）and pH（NaF）ranged from 5.32 to 6.47,4.15to5.73 and 8.40 to 10.55,respectively.Organic matter contents of surface horizons were between 31.51g/kg to 59.48g/kg.Phosphate retention varied between 7.08% to 75.89%.Cation exchange capacity（CEC7）ranged from 2.35cmol（＋）/kg to 39.90cmol（＋）/kg.The major exchangeable cations in all profiles were Ca^2＋ and Mg^2＋.Base saturation ranged from 15.33%to 55.68%.Al and Fe dissolved by dithionite-citrate-bicarbonate（DCB）（Ald,Fed）,acid ammonium oxalate（Alo,Feo）and sodium pyrophosphate（Alp,Fep）showed that AlpAld Alo,FepFeo Fed.Allophane contents were estimated between 0.73% to 9.05%,while ferrihydrite contents were betweens 0.46% to 4.86%.Comparing the four profiles,soils from the volcano cone in Tianchi were less developed than that from Kuandian;on both of the two volcano cones,soils from upside were developed weakly than that from underpart.We found that,soils developed from volcanic tephra were different with ones which were from other parent materials,amorphous mineral such as allophane caused Ald〈Alo.Allophane had significant positive correlation to pH（NaF）and phosphate rentention,as a result,allophane content could be predicted by measuring pH（NaF）and phosphate retention.