模拟酸雨淋溶对紫色母岩风化成土特征的影响研究  

Effects of Simulated Acid Rain Leaching on Weathering and Soil Forming Characteristics of Purple Parent Rock

作　　者：赵吉霞 邓利梅 陆传豪 刘刚才[2] ZHAO Jixia;DENG Limei;LU Chuanhao;LIU Gangcai(College of Resources and Environment,Yunnan Agricultural University,Kunming 650201,China;Institute of Mountain Hazards and Environment,Chinese Academy of Science&Water Resources Ministry,Chengdu 610041,China;University of Chinese Academy of Sciences,Beijing 100049,China)

机构地区：[1]云南农业大学资源与环境学院,昆明650201 [2]中国科学院水利部成都山地灾害与环境研究所,成都610041 [3]中国科学院大学,北京100049

出　　处：《西南大学学报（自然科学版）》2021年第11期151-161,共11页Journal of Southwest University(Natural Science Edition)

基　　金：云南省教育厅科学研究基金项目(2019J0164);国家自然科学基金项目(41471232).

摘　　要：为了分析酸化环境对典型紫色母岩的风化特征的影响规律,本研究以侏罗纪紫色岩层中的遂宁组(J_(3)s)、沙溪庙组(J_(2)s)和蓬莱镇组(J_(3)p)为研究对象,通过室内模拟不同的酸化环境,进行了24次动态淋溶试验.结果表明,与淋溶前各径级的母岩颗粒组成相比,淋溶液酸性越强,3组母岩粒径小于5 mm颗粒含量增幅越大,且遂宁组和沙溪庙组母岩粒径大于20 mm颗粒含量减幅越大,而蓬莱镇组大颗粒减幅随淋溶液pH值变化无统一的规律呈现;3组母岩在模拟不同pH值降雨淋溶处理下的颗粒直径小于5 mm组分含量变幅从大到小依次为遂宁组、沙溪庙组、蓬莱镇组.遂宁组母岩覆土淋溶处理的各粒径变化幅度较裸岩淋溶处理低,但其规律基本一致,且各粒组含量的变幅随覆盖土层厚度的增加基本呈降低趋势.模拟不同pH值降雨淋溶处理下的母岩风化成土速率从大到小依次为遂宁组、沙溪庙组、蓬莱镇组,酸性越强,母岩风化成土率越高,且其成土率随累计淋溶量增加的幅度也越大;经pH值为2.5,3.5,4.5,5.6和7.0的模拟降雨累计淋溶量达2年降雨量时,遂宁组、沙溪庙组和蓬莱镇组母岩的成土率较1年降雨量时分别提高了0.28~1.86倍、0.16~1.82倍和0.27~1.60倍,3组母岩年均成土率与pH值均呈极显著的(p<0.01)指数函数关系.与裸岩淋溶相比,对遂宁组母岩进行覆土淋溶显著降低了母岩的风化成土速率,覆盖土层厚度越深,母岩风化成土率越低.In order to analyze the influence of acidification environment on the weathering process of typical purple parent rocks,the weathering characteristics of purple rocks of the Suining Group(J_(3)s),the Shaximiao Group(J_(2)s),and the Penglaizhen Group(J_(3)p)under different simulated acidizing environments in the laboratory was investigated,and 24 times of dynamic leaching experiment tests were carried out for these purple rock samples.The results showed that compared with the particle composition of the parent rock of each diameter grade before leaching,the more acidic the leaching solution was,the higher the increase ranges of the percentage of particle with a diameter of<5 mm for all the three groups,and the higher the reduction ranges of the percentage of particle with a diameter of≥20 mm for J_(3)s and J_(2)s were,while there was no uniform rule for the reduction of large particles in group J_(3)p with the pH change of the leaching solution.The change range of particle content with a diameter of<5 mm in the three groups of parent rocks after simulated rainfall treatment with different pH values was J_(3)s>J_(2)s>J_(3)p.Under the different depths of covering soil,the variation in particle sizes of J_(3)s showed the same rule with the bare rock,and the change range of each particle size decreased with the increase of the depth of covering soil.The soil formation proportion of parent rocks after simulated rainfall treatment with different pH values were J_(3)s>J_(2)s>J_(3)p.The stronger the acidity was,the higher the soil formation proportion of parent rock was,and the larger the increasing range of soil formation proportion was with the increase of cumulative leached amount.Compared with the amount of simulated rainfall with different pH values to 1a,the soil forming proportion of purple rocks of Groups J_(3)s,J_(2)s and J_(3)p increased by 0.28-1.86,0.16-1.82 and 0.27-1.60 times,respectively,when the amount of simulated rainfall to 2a.The annual soil forming rate of the three groups was in a highly significan

关 键 词：紫色母岩 模拟酸雨 风化特征 

分 类 号：P512.1[天文地球—地质学]