pH对宁夏引黄灌区盐碱化土壤重金属吸附-解吸过程的影响
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摘要
高pH值是宁夏引黄灌区盐碱化土壤的显著特征,研究盐碱化土壤的高pH值对不同重金属元素的富集和释放规律,可为宁夏引黄灌区盐碱化土壤重金属污染的控制及治理提供科学依据。通过调节pH值,采用土柱淋溶的方法,模拟盐碱化土壤的Cd和Pb的吸附-解吸过程,研究pH对盐碱化土壤重金属Cd、Pb吸附-解吸特征、形态和生物活性的影响。结果表明:在试验设定的pH范围内,盐碱化土壤对Cd的吸附量随着pH值的升高而呈升高趋势,在pH值为8时达到峰值,对Pb的吸附量随pH的升高呈波动状变化状态,在pH值为10时达到峰值;同时,Cd的解吸量随吸附量增加而线性增大,解吸量随pH升高而增加,但解吸量随吸附量变化而变化的幅度随pH值的升高而减小,Pb的解吸量随吸附量增加而呈选择性增加。随着pH的升高,Cd可交换态和碳酸盐结合态的含量变化趋势相反,生物活性基本不变,其Fe/Mn氧化物结合态、有机结合态和残渣态的含量不变;Pb可交换态和碳酸盐结合态的含量随着pH的升高而升高,生物活性增强,有机结合态的含量减少,Fe/Mn氧化物结合态和残渣态的含量不变。宁夏引黄灌区盐碱化土壤的高pH值可以降低土壤对重金属Cd、Pb的吸附,缓解重金属污染引起的生态、粮食及其食品安全压力。
High pH value is an obvious characteristic of saline-alkali land in Ningxia Yellow River Irrigation Region. It is meaningful to analyze the rules of different heavy metal enrichment and release for heavy metal pollution control and treatment in soil of the Ningxia Yellow River irrigation region. The pH value regulation, soil column leaching and the Tessier five steps of continuous extraction methods were employed for studying the effects of high pH value on adsorption and desorption process of cadmium and lead, morphologie and biological activities in saline-alkali soil. The results indicated that the adsorption amount of cadmium increased positively to increasing soil pH. The peak value reached the maximum value at pH of 8, but the changing trend for lead with the increment of pH was instable, reaching the maximum value at pH of 10. Meanwhile the desorption amount showed a linearly increasing trend with the improvement of adsorption, and it exhibited the same increasing trend as the pH arising. The variation extent between desorption and adsorption amount decreased negatively to the increasing pH value. In contrast, the desorption of lead increased selectively with its adsorption. As for cadmium, the amount changes of exchangeable form and the carbonate bound form were opposite with the increasing pH value separately. The biological activities maintained unchanged, as well as the content of combined forms with Fe-Mn oxide form and organic and residuals. While for Pb, the amount of above two forms increased positively to increasing soil pH, in which the biological activities increased and the content of organic form decreased negatively. But its Fe-Mn oxide and residuals forms were not changed. Therefore, it can be concluded that the high pH of saline-alkaline soil in Ningxia Yellow River Irrigation Region can reduce the heavy metal adsorption of cadmium/lead and relieve the pressure of ecological, grain and food safety due to heavy metal contamination.
High pH value is an obvious characteristic of saline-alkali land in Ningxia Yellow River Irrigation Region. It is meaningful to analyze the rules of different heavy metal enrichment and release for heavy metal pollution control and treatment in soil of the Ningxia Yellow River irrigation region. The pH value regulation, soil column leaching and the Tessier five steps of continuous extraction methods were employed for studying the effects of high pH value on adsorption and desorption process of cadmium and lead, morphologie and biological activities in saline-alkali soil. The results indicated that the adsorption amount of cadmium increased positively to increasing soil pH. The peak value reached the maximum value at pH of 8, but the changing trend for lead with the increment of pH was instable, reaching the maximum value at pH of 10. Meanwhile the desorption amount showed a linearly increasing trend with the improvement of adsorption, and it exhibited the same increasing trend as the pH arising. The variation extent between desorption and adsorption amount decreased negatively to the increasing pH value. In contrast, the desorption of lead increased selectively with its adsorption. As for cadmium, the amount changes of exchangeable form and the carbonate bound form were opposite with the increasing pH value separately. The biological activities maintained unchanged, as well as the content of combined forms with Fe-Mn oxide form and organic and residuals. While for Pb, the amount of above two forms increased positively to increasing soil pH, in which the biological activities increased and the content of organic form decreased negatively. But its Fe-Mn oxide and residuals forms were not changed. Therefore, it can be concluded that the high pH of saline-alkaline soil in Ningxia Yellow River Irrigation Region can reduce the heavy metal adsorption of cadmium/lead and relieve the pressure of ecological, grain and food safety due to heavy metal contamination.
引文
DAVIS J A.1984.Complexation of trace metals by adsorbed natural organic matter[J].Geochimicaet Cosmochimica Acta,48(4):679-691.
JAMES R O,HEALY T W.1972.Adsorption of hydrolyzable metal ions at the oxide-water interface.Ⅲ.A thermodynamic model of adsorption[J].Journal of Colloid and Interface Science,40(1):65-80.
LU Y,ZHU F,CHEN J,et al.2007.Chemical fractionation of heavy metals in urban soils of Guangzhou,China[J].Environmental Monitoring and Assessment,134(1-3):429-439.
MARGUíE,QUERALT I,CARVALHO M L,et al.2007.Assessment of metal availability to vegetation(Betula pendula)in Pb-Zn ore concentrate residues with different features[J].Environmental Pollution,145(1):179-184.
NAIDU R,BOLAN N S,KOOKANA R S,et al.1994.Ionic-strength and p H effects on the sorption of cadmium and the surface charge of soils[J].European Journal of Soil Science,45(4):419-429.
OLAJIRE A A,AYODELE E T,OYEDIRDAN G O,et al.2003.Levels and speciation of heavy metals in soils of industrial Southern Nigeria[J].Environmental Monitoring and Assessment,85(2):135-155.
TESSIER A,CAMPBELL P G C,BISSON M.1979.Sequential extraction procedure for the speciation of particulate trace metal[J].Analytical chemistry,51(7):844-851.
ZENG F R,ALI S,ZHANG H T,et al.2011.The influence of p H and organic matter content in paddy soil on heavy metal availability and their uptake by rice plants[J].Environmental Pollution,159(1):84-91.
程镜润,陈小华,刘振鸿,等.2014.脱硫石膏改良滨海盐碱土的脱盐过程与效果试验研究[J].中国环境科学,34(6):1505-1513.
丁中元.1989.重金属在土壤-作物中分布规律研究[J].环境科学,10(5):78-85.
郭鹏,郭平,康春莉,等.2008.城市土壤吸附重金属动力学特征及其与土壤理化性质的关系[J].环境保护科学,34(6):23-26.
胡宁静,骆永明,宋静.2007.长江三角洲地区典型土壤对镉的吸附剂其与有机质、p H和温度的关系[J].土壤学报,44(3):437-443.
李小平,徐长林,刘献宇,等.2015.宝鸡城市土壤重金属生物活性与环境风险[J].环境科学学报,35(4):1241-1249.
陆泗进,王业耀,何立环.2014.会泽某铅锌矿周边农田土壤重金属生态风险评价[J].生态环境学报,23(11):1832-1838.
罗成科,毕江涛,肖国举,等.2017.宁东基地不同工业园区周边土壤重金属污染特征及其评价[J].生态环境学报,26(7):1221-1227.
罗远恒,顾雪元,吴永贵,等.2014.钝化剂对农田土壤镉污染的原位钝化修复效应研究[J].农业环境科学学报,33(5):890-897.
马祥爱,秦俊梅,冯两蕊.2010.长期污水灌溉条件下土壤重金属形态及生物活性的研究[J].中国农学通报,26(22):318-322.
普锦成,符娟林,章明奎.2008.土壤性质对水稻土中外源镉和铅生物有效性的影响[J].生态环境,17(6):2253-2258.
乔冬梅,齐学斌,庞鸿宾,等.2011.不同p H值条件下重金属Pb2+的吸附解吸研究[J].土壤通报,42(1):38-41.
汪霞,南忠仁,武文飞,等.2010.干旱区绿洲土壤中重金属的形态分布及生物有效性研究[J].生态环境学报,19(7):1663-1667.
王学锋,尚菲,马鑫,等.2013.p H和腐植酸对镉、镍、锌在土壤中的形态分布及其生物活性的影响[J].科学技术与工程,13(27):1671-1815.
曾祥峰,王祖伟,魏树和,等.2014.碱性条件下胡敏酸吸附镉的特征研究[J].生态环境学报,23(10):1691-1696.
中华人民共和国环境保护部.《土壤环境质量标准》(修订)(GB15618-2008)[S].国家质量监督检验检疫总局.
JAMES R O,HEALY T W.1972.Adsorption of hydrolyzable metal ions at the oxide-water interface.Ⅲ.A thermodynamic model of adsorption[J].Journal of Colloid and Interface Science,40(1):65-80.
LU Y,ZHU F,CHEN J,et al.2007.Chemical fractionation of heavy metals in urban soils of Guangzhou,China[J].Environmental Monitoring and Assessment,134(1-3):429-439.
MARGUíE,QUERALT I,CARVALHO M L,et al.2007.Assessment of metal availability to vegetation(Betula pendula)in Pb-Zn ore concentrate residues with different features[J].Environmental Pollution,145(1):179-184.
NAIDU R,BOLAN N S,KOOKANA R S,et al.1994.Ionic-strength and p H effects on the sorption of cadmium and the surface charge of soils[J].European Journal of Soil Science,45(4):419-429.
OLAJIRE A A,AYODELE E T,OYEDIRDAN G O,et al.2003.Levels and speciation of heavy metals in soils of industrial Southern Nigeria[J].Environmental Monitoring and Assessment,85(2):135-155.
TESSIER A,CAMPBELL P G C,BISSON M.1979.Sequential extraction procedure for the speciation of particulate trace metal[J].Analytical chemistry,51(7):844-851.
ZENG F R,ALI S,ZHANG H T,et al.2011.The influence of p H and organic matter content in paddy soil on heavy metal availability and their uptake by rice plants[J].Environmental Pollution,159(1):84-91.
程镜润,陈小华,刘振鸿,等.2014.脱硫石膏改良滨海盐碱土的脱盐过程与效果试验研究[J].中国环境科学,34(6):1505-1513.
丁中元.1989.重金属在土壤-作物中分布规律研究[J].环境科学,10(5):78-85.
郭鹏,郭平,康春莉,等.2008.城市土壤吸附重金属动力学特征及其与土壤理化性质的关系[J].环境保护科学,34(6):23-26.
胡宁静,骆永明,宋静.2007.长江三角洲地区典型土壤对镉的吸附剂其与有机质、p H和温度的关系[J].土壤学报,44(3):437-443.
李小平,徐长林,刘献宇,等.2015.宝鸡城市土壤重金属生物活性与环境风险[J].环境科学学报,35(4):1241-1249.
陆泗进,王业耀,何立环.2014.会泽某铅锌矿周边农田土壤重金属生态风险评价[J].生态环境学报,23(11):1832-1838.
罗成科,毕江涛,肖国举,等.2017.宁东基地不同工业园区周边土壤重金属污染特征及其评价[J].生态环境学报,26(7):1221-1227.
罗远恒,顾雪元,吴永贵,等.2014.钝化剂对农田土壤镉污染的原位钝化修复效应研究[J].农业环境科学学报,33(5):890-897.
马祥爱,秦俊梅,冯两蕊.2010.长期污水灌溉条件下土壤重金属形态及生物活性的研究[J].中国农学通报,26(22):318-322.
普锦成,符娟林,章明奎.2008.土壤性质对水稻土中外源镉和铅生物有效性的影响[J].生态环境,17(6):2253-2258.
乔冬梅,齐学斌,庞鸿宾,等.2011.不同p H值条件下重金属Pb2+的吸附解吸研究[J].土壤通报,42(1):38-41.
汪霞,南忠仁,武文飞,等.2010.干旱区绿洲土壤中重金属的形态分布及生物有效性研究[J].生态环境学报,19(7):1663-1667.
王学锋,尚菲,马鑫,等.2013.p H和腐植酸对镉、镍、锌在土壤中的形态分布及其生物活性的影响[J].科学技术与工程,13(27):1671-1815.
曾祥峰,王祖伟,魏树和,等.2014.碱性条件下胡敏酸吸附镉的特征研究[J].生态环境学报,23(10):1691-1696.
中华人民共和国环境保护部.《土壤环境质量标准》(修订)(GB15618-2008)[S].国家质量监督检验检疫总局.
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