菹草对铵氮和硝氮急性胁迫的响应  

Response of Potamogeton crispus to Acute Stress of NH_4^+-N or NO_3^--N

作　　者：马剑敏[1] 靳同霞[1] 贺锋[2] 成水平[2] 赵强[2] 吴娟[2] 吴振斌[2] 

机构地区：[1]河南师范大学生命科学学院,河南省环境污染控制重点实验室,河南新乡453007 [2]中国科学院水生生物研究所,湖北武汉430072

出　　处：《环境科学与技术》2009年第5期26-30,87,共6页Environmental Science & Technology

基　　金：国家"十五"重大科技专项(2002AA601021);河南省科技攻关项目(0624440039);淡水生态与生物技术国家重点实验室开放课题(06FB03)

摘　　要：利用水族箱研究了在单一的铵氮和硝氮急性胁迫下,3d内菹草的现存量、生产力、叶绿素与可溶性蛋白质含量以及SOD和POD活性的变化特点。结果表明:铵氮胁迫下,菹草现存量增加百分比与铵氮浓度间显著负相关;铵氮>1.56mg/L时,菹草现存量、生产力、可溶性蛋白含量开始明显下降,生长受到抑制;叶绿素含量在胁迫6h时无明显变化,在高浓度的铵氮胁迫24和72h时,含量明显下降;随着胁迫时间延长,SOD活性明显升高时对应的胁迫浓度越来越低,而在高浓度的铵氮胁迫下,活性明显下降;POD活性随着胁迫浓度的提高,在6、24和72h时,均先升后降。在0～200mg/L的硝氮胁迫下,菹草现存量先升后降,但其最低值与对照无明显差异;随着胁迫浓度增加,蛋白质含量在胁迫6h时无明显变化,24和72h时先升后降;叶绿素含量无明显变化,SOD活性持续升高;POD活性除在>25mg/L的硝氮作用72h时下降外,均随硝氮浓度增加而增加。总生产力在硝氮≤100mg/L时无明显下降。NH4+对菹草的毒性远大于NO3-。Characteristics were studied for the standing crops, productivities, soluble protein content, SOD and POD activities of Potamogeton crispus changed under the stress of NH4^＋-N or NO3^--N in aquaria within 3 days. Results showed that the increased percent of standing crop of P. crispus was in negative correlation to the concentration of NH4^＋-N under the stress of N^＋-N. When NH^＋-N was above 1.56mg/L, the standing crop, productivity and solubie protein content began to decrease, the growth of P. crispus was inhibited. With the prolonging of stress time, N^＋--N concentration that SOD activity increased obviously was getting lower and lower. Under stress of high concentration of NH4^＋-N, SOD activity decreased markedly. With increasing of NH4^＋-N concentration, POD activity first increased and then decreased at the 6th, 24th and 72nd hours. Under the stress of NO3--N0-200mg/L, the increased percent of standing crop of P. crispus first increased and then decreased, with the lowest standing crop no obvious difference with the control group. With increasing NO3^--N concentration, soluble protein content had no obvious difference comparing to the control group at the 6th hour, but increased firstly and then decreased at the 24th and 72nd hours. SOD and POD activities continuously increased with increasing NO3-N concentration, but POD activity decreased when stress time was at the 72nd hour and NO3^--N above 25mg/L. When NO3^--N was less than 100mg/L, gross productivity did not decrease markedly. Toxicity of NH4^＋ to P. crispus was much more than that of NO3^-.

关 键 词：菹草 铵氮 硝氮 急性胁迫 

分 类 号：X503.23[环境科学与工程—环境工程] X171.5