3种有机改良剂对铅锌矿尾砂适生性改善的研究  

Study on Suitability of Pb/Zn Mine Tailings Using Three Different Organic Amendments

作　　者：代德敏 蒋旭升 刘杰[1,2] 王路洋 陈诗奇 韩庆坤 DAI Demin;JIANG Xusheng;LIU Jie;WANG Luyang;CHEN Shiqi;HAN Qingkun(Guangxi Key Laboratory of Environmental Pollution Control Theory and Technology,Guilin University of Technology,Guilin 541004,P.R.China;Technical Innovation Center of Mine Geological Environmental Restoration Engineering in Southern Karst Area,Ministry of Natural Resources,Nanning 530022,P.R.China)

机构地区：[1]桂林理工大学广西环境污染控制理论与技术重点实验室,广西桂林541004 [2]自然资源部南方石山地区矿山地质环境修复工程技术创新中心,广西南宁530022

出　　处：《生态环境学报》2023年第4期784-793,共10页Ecology and Environmental Sciences

基　　金：国家自然科学基金项目(32271700,52230006);广西自然科学基金重点项目(2020GXNSFDA297018)。

摘　　要：铅锌矿尾砂由于肥力低、物理结构差且重金属镉(Cd)铅(Pb)锌(Zn)浓度高,植物难以生长,从而严重制约了尾砂库的生态恢复。利用改良剂改善尾砂的适生性是尾砂库生态恢复的重要方法。通过基质改良试验探究添加不同质量分数(1%、2.5%、5%)的发酵羊粪、污泥和椰壳生物炭对铅锌矿尾砂养分、物理结构的改良效果和对重金属镉铅锌的固定效果,再通过黑麦草(Lolium perenne L.)盆栽试验验证对适生性的改善效果。结果表明,添加改良剂使有效态氮、磷、钾以及有机质分别提高了0.87-9.56、1.87-37.7、1.87-43.7和0.85-7.28倍。添加质量分数为2.5%时,3种改良剂对尾砂的导水性、总孔隙度和持水性的积极影响最为显著,表现为发酵羊粪>生物炭>污泥。此外,3种改良剂显著(P<0.05)降低有效态重金属质量分数,Cd、Pb、Zn分别降低了28.6%-64.6%、30.4%-70.6%、14.4%-45.5%。其中,椰壳生物炭对3种重金属的固定效果最好。添加改良剂显著提高了黑麦草的发芽率、总高度和总干质量分别提高了16.1%-20.3%、10.8%-48.9%和7.55%-19.5%,其中发酵羊粪效果最好。因此,发酵羊粪、污泥和椰壳生物炭可作为改良剂改善铅锌矿尾砂的适生性并促进植物生长。Pearson相关性分析表明,植物地上部分干质量和株高与阳离子交换量和速效钾呈极显著(P<0.01)正相关,与饱和导水率和有效态重金属呈极显著(P<0.01)负相关。植物根干质量和根长均与饱和含水量呈显著正相关,而与1-2 mm的粒径呈显著负相关。该文可为养分贫瘠、物理结构差和高重金属污染尾砂库的植被恢复提供理论依据。Ecological restoration is difficult to construct in the Pb/Zn tailings due to the low nutrient concentrations,poor physical structure and high heavy metal(cadmium,Cd;lead,Pb;zinc,Zn)concentrations.Amendments are used to improve the suitability of the tailings,which is an important method for the ecological restoration of tailings ponds.In this experiment,fermented sheep manure,sludge and coconut shell biochar with different mass fractions(1%,2.5%,5%)were used to investigate the effects of fertility and physical structure and heavy metal(Cd,Pb,Zn)bioavailability of Pb/Zn mine tailings and then the improvement effects were verified by pot experiment of ryegrass.The results showed that the available nitrogen,phosphorus,potassium and organic matter increased by 0.87-9.56 times,1.87-37.7 times,1.87-43.7 times and 0.85-7.28 times,respectively.The most significant effects on hydraulic conductivity,total porosity and water retention of tailing sand were observed at the addition rate of 2.5%and showed that fermented sheep manure>biochar>sludge.Furthermore,bioavailability of heavy metals was significantly(P<0.05)reduced by 28.6%-64.6%(Cd),30.4%-70.6%(Pb),and 14.4%-45.5%(Zn),and coconut shell biochar had the most significant effect.Ryegrass’s germination,height and total dry mass had been increased by 16.1%-20.3%,10.8%-48.9%and 7.55%-19.5%,respectively,and fermented sheep manure is the best.Thus,fermented sheep manure,sludge and coconut shell biochar could be used as amendments to improve the suitability of Pb/Zn tailings and promote plant growth.Furthermore,Pearson’s correlation analysis showed that aboveground dry mass and height were highly significantly(P<0.01)and positively correlated with cation exchange capacity and available potassium,but significant(P<0.01)negative correlations were observed with saturated hydraulic conductivity and available state heavy metal.Plant root dry mass and root length were observed to be significantly and positively correlated with saturated water content;in contrast,they were signif

关 键 词：铅锌尾砂 基质改良 有机改良剂 养分 物理性质 适生性 

分 类 号：X53[环境科学与工程—环境工程]