湖北郧县黄坪村黄土-古土壤序列体积分形维数特征及其环境意义  

Volumetric Fractal Dimension Characteristics of Loess-Paleosol Sequence and Its Environmental Significance in Huangping Village,Yunxian County,Hubei Province

作　　者：刘涛 庞奖励 黄春长 查小春 周亚利 毛沛妮 胡慧 Liu Tao;Pang Jiangli;Huang Chunchang;Zha Xiaochun;Zhou Yali;Mao Peini;Hu Hui(School of Geography and Tourism,Shaanxi Normal University/National Demonstration Center for Experimental Geography Education,Xi’an 710119,China)

机构地区：[1]陕西师范大学地理科学与旅游学院/地理学国家级实验教学示范中心,陕西西安710119

出　　处：《山东农业科学》2018年第4期73-78,共6页Shandong Agricultural Sciences

基　　金：国家自然科学基金项目(41271108;41371029);国家社会科学基金项目(14BZS070);中央高校基本科研经费项目(GK201704014)

摘　　要：本研究运用体积分形维数模型计算了湖北郧县黄坪村(HPC)剖面土壤体积分形维数,剖面分形维值介于2.52~2.78,古土壤S_0的分形维数值最大,马兰黄土L_1最小,剖面整体分形维数值的大小关系为D_(S0)>D_(Lt)>D_(L0)>D_(L1)。研究发现,分形维数值与粘粒含量呈正相关,与粗粉砂含量呈负相关,与磁化率和CIA值成正比,说明分形维数也可以指示成壤环境的演变,即分形维数值的高值,指示气候较为暖湿,反之指示的是气候较为干冷。HPC剖面的分形特征揭示了汉江地区的气候变化历史:晚更新世时期,L_1的分形维数仅为2.61,说明气候较为冷干,成壤作用微弱;全新世早期,L_t的分形维数相对L_1增至2.71,说明气候条件改善,气温回暖;全新世中期,S_0的分形维数相对于L_t增至2.75,表明气候暖湿,成壤作用强烈;全新世晚期,L_0的分形维数相对于S_0降至2.70,说明汉江地区气候转凉。The volumetric fractal dimensions of particle-size(D)in soil profile of Huangping Village(HPC),Yunxian County,Hubei Province were calculated by the volumetric fractal dimension mode.The fractal dimension values were between 2.52 and 2.78,and the highest one was in the paleosol layer(S 0)and the lowest one was in the Malan loess layer(L 1).The fractal dimension values in the whole profiles was ranked as D S0>D Lt>D L0>D L1.This study discovered that the fractal dimension values were positively correlated to the clay content,negatively correlated to the coarse silt content,and was in direct proportion to magnetic susceptibility and CIA value.The fractal dimension could be used to reflect the evolution of pedogenic environment.The higher value reflected warm and humid,whereas lower value reflected arid and cold.The fractal characteristics of HPC soil profile indicted the history of climate change in Hanjiang area.During the late pleistocene,the fractal dimension value of L 1 was only 2.61,indicated cold climate and weak pedogenesis.During the early holocene,the value in L t increased to 2.71 compared with L 1,which indicated the climate was improved and warmer.During the middle holocene,the value in S 0 increased to 2.75,indicated warm and humid climate and strong pedogenesis.During the late holocene,the value in L 0 reduced to 2.70,indicated that the climate in Hanjiang area became cool.

关 键 词：体积分形维数 粒度组成 磁化率 CIA值 沉积环境 

分 类 号：S151.3263[农业科学—土壤学]