摘要
煤矸石是煤炭生产过程中产生的固体废弃物。植被恢复是减少煤矸石堆场重金属淋溶迁移的主要途径,而露天煤矸石基质改良是植被恢复的基础。通过盆栽和野外堆场小区黑麦草种植试验以及淋溶试验,探究白云岩砂改良煤矸石基质对黑麦草生长和重金属淋溶的调控效应。结果表明:在添加10%~30%白云岩砂的煤矸石基质上黑麦草的地上部生物量和叶绿素含量均出现显著的增加,黑麦草植株对氮和磷的吸收量也明显的增加。同时,添加10%~30%白云岩砂的煤矸石基质中有效态Mn、Cd和Zn质量分数均出现显著性降低,且煤矸石基质渗透水中Fe、Mn、Cd和Zn质量分数也出现显著性的下降;特别是煤矸石中添加20%~30%白云岩砂时,煤矸石基质中有效态Fe和Mn质量分数及其渗透水Fe和Mn质量浓度均出现明显的降低。在煤矸石中添加适量白云岩砂有利于降低煤矸石基质中重金属的生物有效性和水溶态重金属的质量浓度,从而明显减少煤矸石基质中Fe、Mn淋溶迁移对水环境质量的影响。
[Background]Coal gangue is a solid waste generated in the process of coal production,the leaching and migration of heavy metal elements such as Fe and Mn in the coal gangue piled in the open air will cause obvious pollution to the surrounding water body of the storage yard.Vegetation restoration is the main way to reduce the leaching and migration of heavy metals in coal gangue dumps,but the improvement of open gangue substrate is the basis of vegetation restoration.[Methods]This study selected the closed coal mining area in the central region of Guizhou province as the research object,4 treatment plots were set up in the abandoned open-air gangue yard for many years,and ryegrass were planted in the coal gangue with 0,20,40 and 60 kg/m^(2)of dolomite sand in a depth of 20 cm and mixed evenly.In addition,the mixed samples of coal gangue(0-30 cm)on the surface of the gangue yard were collected and brought back to the laboratory for pot experiments,and ryegrass(Lolium perenne)was planted on mixed substrates with dolomite sand content of 0,10%,20%and 30%,respectively.[Results]1)The biomass and chlorophyll content of ryegrass on the coal gangue substrate added with 10%-30%dolomite sand significantly increased,and the absorption of N,P and K by ryegrass plants also increased significantly with the order of their effects was P>N>K.2)On the other hand,the contents of available Mn,Cd,and Zn in the coal gangue matrix added with 10%-30%dolomite sand significantly reduced,especially,when 20%-30%dolomite sand was added to coal gangue,the content of available Fe and Mn in the gangue matrix obviously reduced;this effect was closely related to the significant increase in pH of the gangue matrix after adding 20%-30%dolomite sand to the gangue matrix.3)At the same time,after the dolomite sand improved the gangue matrix,the leaching and migration of heavy metal elements significantly reduced,and the concentration of Fe,Mn,Cd,and Zn in the infiltration water of the coal gangue matrix with 10%to 30%dolomite sand decreased significant
作者
刘元生
陈祖拥
刘方
卜通达
杨丽
LIU Yuansheng;CHEN Zuyong;LIU Fang;BU Tongda;YANG Li(Environment and Resource Institute of Guizhou University,550025,Guiyang,China)
出处
《中国水土保持科学》
CSCD
北大核心
2023年第5期138-145,共8页
Science of Soil and Water Conservation
基金
国家自然科学基金“煤矿废弃地煤矸石水界面锰迁移的生态规律与调控机制”(41661094)
贵州省科技计划项目(黔科合平台人才[2017]5788号)。
关键词
煤矸石
白云岩砂
黑麦草
生长状况
重金属
淋溶
养分吸收
coal gangue
dolomite sand
ryegrass
growth status
heavy metal
leaching
nutrient absorption
