不同氮形态对铅胁迫下苏丹草根系形态及铅吸收富集特征的影响  

Effects of Nitrogen of Different Forms on Sorghum Sudanense Root Morphology and Characteristics of Lead Absorption and Accumulation Under Lead Stress

作　　者：袁菊红[1] 胡绵好[2] 殷乾亮[2] 陈祎[2] 

机构地区：[1]江西财经大学园林系,江西南昌330032 [2]江西财经大学资源环境系,江西南昌330032

出　　处：《水土保持通报》2012年第2期69-73,共5页Bulletin of Soil and Water Conservation

基　　金：江西省自然科学基金项目"鄱阳湖富营养化与重金属污染相互作用及生态效应研究"(2009GQH0027);江西省教育厅项目"鄱阳湖富营养化水体中氮磷与重金属相互作用机理及其生态效应"(GJJ10115)

摘　　要：为进一步研究富营养化水体中不同氮形态和重金属对修复植物的交互作用,通过水培试验研究了水体中不同形态氮培养对铅胁迫下苏丹草根系形态及其对铅吸收富集的影响。结果表明,水体Pb(0.5mmol/L)污染时,不同氮形态培养虽然对苏丹草根系形态有一定的影响,但没达到显著性差异,然而对苏丹草根系中丙二醛(MDA)含量及其各器官生物量的影响达显著差异(p<0.05),NH4—N营养液培养的苏丹草根系MDA含量比NO3—N,NO2—N营养液培养的分别高出了4.6和1.6倍;NO3—N营养液培养的苏丹草根、茎、叶生物量比NH4—N营养液培养的分别高出了28.7%,19.6%和23.9%,比NO2—N营养液培养的高出37.6%,30.9%和36.7%。水体Pb(0.5 mmol/L)污染时,NO3—N营养液培养的苏丹草根中Pb浓度明显比NH4—N营养液培养的高出2倍多,且其地下富集系数最大;NO2—N营养液培养的苏丹草茎中Pb浓度明显比NH4—N营养液培养的高出近8倍,且其对铅的转运能力影响作用最强。这表明受重金属污染的富营养化水体中如存在不同形态氮,在一定程度上还有利于削弱重金属对修复植物的毒性作用,增大水体对某些重金属的环境容量。Effect of nitrogen of different forms on Sorghum sudanense root morphology and lead（Pb） absorption and accumulation under Pb stress were studied using hydroponics experiment,addressing the interaction between the plant and different nitrogen forms and heavy metals for phytoremediation application.The results indicate that the different N forms had some insignificant effects on the root morphology of S.sudanense with Pb pollution level of 0.5 mmol/L.However,the MDA（Malon dialde hyde）contents of the roots and the biomass of each organ of S.sudanense were significantly（p0.05） influenced： the MDA content of S.sudanense root in the NH4—N culture solution was 4.6 and 1.6 times higher than those in NO3—N and NO2—N culture solutions,and the root,stem and leave biomasses in the NO3—N culture solution were higher than those in NH4—N culture solution by 28.7%,19.6% and 23.9%,and higher than those in NO2—N culture solution by 37.6%,30.9% and 36.7%,respectively.With Pb pollution level of 0.5 mmol/L,the root in NO3—N treatment had the largest enrichment coefficients and Pb concentration that was over 2 times higher than that in NH4—N culture solution,and Pb concentration of the stem in the NO2—N treatment was over 8 times higher than that of NH4—N treatment,indicating a high transport capability of Pb.This suggests that if the existence of different forms of nitrogen in the eutrophication water with heavy metal pollution may to some extent weaken the toxic effect of the heavy metal on the remediating plant,and increase the environment capacity of the water.

关 键 词：氮形态 铅胁迫 苏丹草 

分 类 号：X174[环境科学与工程—环境科学]