室内绿狐尾藻湿地系统对高氨氮废水的净化作用

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余红兵, 何洋, 李红芳, 刘锋, 张树楠, 王迪, 肖润林. 室内绿狐尾藻湿地系统对高氨氮废水的净化作用. 草业科学, 2016,33(11):2189-2195
Yu Hong-bing, He Yang, Li Hong-fang, Liu Feng, Zhang Shu-nan, Wang Di, Xiao Run-lin. Purification effects of indoor Myriophyllum elatinoides wetland system on ammonium nitrogen wastewater . Pratacultural Science,2016,33(11): 2189-2195 复制到剪切板

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《草业科学》编辑部

室内绿狐尾藻湿地系统对高氨氮废水的净化作用

余红兵¹, 何洋^2,³, 李红芳², 刘锋², 张树楠^2,³, 王迪^2,³, 肖润林²

1.湖南城市学院建筑与城市规划学院,湖南益阳 413000

2.中国科学院亚热带农业生态研究所亚热带农业生态过程重点实验室,湖南长沙 410125

3.中国科学院大学,北京 100049

通讯作者:肖润林(1963-),男,湖南衡东人,研究员,本科,主要从事农村污染水体氮磷减控研究。E-mail:xiaorl@isa.ac.cn

第一作者:余红兵(1976-),女,湖南益阳人,副教授,博士,主要从事园林植物及沟渠湿地植物净化研究。E-mail:bingbingyu76@163.com

收稿日期: 2016-08-30

基金: “十二五”国家科技支撑计划项目(2014BAD14B05); 湖南省战略性新兴产业成果转化项目(2015GK1014); 湖南省科技支撑计划(2015NK3003)

摘要

本研究以绿狐尾藻( Myriophyllum elatinoides)湿地系统为对象,分析绿狐尾藻湿地系统中NH₄⁺-N的去除规律及氮质量平衡。结果表明,试验第28天,在200和400 mg·L^-1 N H₄⁺-N两个处理中,水体全氮(TN)去除率分别为86.1%和77.7%,N H₄⁺-N去除率分别为89.8%和78.8%。根据氮质量平衡得出,在200和400 mg·L^-1 N H₄⁺-N两个处理中分别有14.7%和30.2%的外源N H₄⁺-N直接被底泥吸附,25.3%和11.0%转化成底泥NO₃^--N,29.7%和12.7%被绿狐尾藻直接吸收利用,14.0%和23.3%残留在水体,剩余16.3%和22.8%可能被微生物硝化反硝化作用去除。研究结果表明,绿狐尾藻对氨氮有较好的净化效果,为其在人工湿地的应用提供了科学依据。

关键词: 绿狐尾藻; 氨氮; 氮去除; 植物吸收; 硝化和反硝化作用; 氮质量平衡

中图分类号:Q945.12 文献标志码:A 文章编号:1001-0629(2016)11-2189-07 doi: 10.11829/j.issn.1001-0629.2016-0272

Purification effects of indoor Myriophyllum elatinoides wetland system on ammonium nitrogen wastewater

Yu Hong-bing¹, He Yang^2,³, Li Hong-fang², Liu Feng², Zhang Shu-nan^2,³, Wang Di^2,³, Xiao Run-lin²

1.College of Architecture and Urban Planning, Hunan City University, Yiyang, 413000, China

2.Key Laboratory of Agro-ecological Processes in Subtropical Regions, Institute of Subtropical Agriculture, Chinese Academy of Sciences, Changsha 410125, China

3.University of Chinese Academy of Science, Beijing 100049, China

Corresponding author:Xiao Run-lin E-mail:xiaorl@isa.ac.cn

Abstract

In the present study, the ammonium nitrogen removal characteristics and nitrogen mass balance in indoor Myriophyllum elatinoides wetland system were analysis. The results showed after 28 days treatment with 200 and 400 mg·L^-1 NH₄⁺-N, the removal rates of total nitrogen (TN) and N H₄⁺-N in artificial wastewater were 77.7% and 86.1% , 89.8% and 78.8%, respectively. According to the nitrogen mass balance, 14.7% and 30.2% of the exogenous N H₄⁺-N were transformed into sediment N H₄⁺-N and 25.3% and 11% of exogenous N H₄⁺-N were transformed into sediment NO₃-N by 200 mg·L^-1 N H₄⁺-N and 400 mg·L^-1 N H₄⁺-N treatments; 29.7% and 12.7% of exogenous N H₄⁺-N was absorbed by M. elatinoides; 14.0% and 23.3% of exogenous N H₄⁺-N became residual nitrogen in the water and 16.3% and 22.8% of exogenous N H₄⁺-N eventually to nitrification and denitrification removal. The results suggested that M. elatinoides can effectively purify ammonium nitrogen which provides scientific basis for its application in artificial wetland.

Keyword: Myriophyllum elatinoides; artificial wetland; nitrogen removal; nitrification and denitrification; nitrogen mass balance

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近年来, 随着工业发展和养殖业的集约化, 高氨氮废水排放造成了严重的环境问题^[1]。氮引起的地表水、地下水污染, 已对农业、渔业等多个行业造成危害, 已威胁到人们的健康安全^[2]。常用的氨氮废水处理方法有厌氧/好氧工艺(A/O)、活性污泥法(SBR)、膜生物反应器(MBR)、氧化沟、人工湿地等^{[3, 4]}。活性污泥法和膜生物反应器等处理工艺程序复杂, 技术成本较高。与其它处理工艺相比, 人工湿地是一种简单有效、价格低廉的处理技术, 已广泛用于处理农业、工业、矿山废水和生活污水^{[5, 6, 7]}。

人工湿地由植物-基质-微生物组成, 在其内部发生着许多物理、化学和生物过程。在人工湿地中, 氨氮去除的主要途径有植物吸收、基质吸附、氨挥发和微生物硝化反硝化等^{[8, 9]}。水生植物对于人工湿地的氮去除起着重要作用。除植物本身对氮素直接吸收外, 水生植物的存在还可改变基质的理化特性、提高系统中溶解氧含量^{[10, 11]}, 同时, 水生植物还可作为先锋植物用于相应重金属污染严重区域^{[12, 13]}。然而, 水体中氨氮浓度过高, 会对水生植物产生一定的毒害作用, 并抑制其正常生长^[14]。由于许多植物不能耐受高氨氮, 因此, 人工湿地在处理高氨氮废水的应用中受到限制。绿狐尾藻(Myriophyllum elatinoides)为小二仙草科(Haloragidaceae)狐尾藻属, 系多年生沉水或浮水草本植物, 其不仅营养价值高, 是优质饲料和绿肥, 而且对水体氮、磷也有较强的吸收能力。研究表明, 绿狐尾藻对高氨氮具有较强的耐受性, 可作为生态治理的先锋植物^[15]; 同时相对于大薸(Pistia stratiotes)、凤眼莲(Eichhornia crassipes)等水生植物, 具有较小的生态风险^[16]。且处理废水的绿狐尾藻净化系统中微生物对沉积物的脱氮发挥重要作用^{[17, 18]}, 但有关绿狐尾藻湿地对高氨氮废水的去除效率及其主要去除途径的报道不多。本研究以绿狐尾藻湿地系统为对象, 分析绿狐尾藻湿地系统对不同负荷氨氮的去除特征, 研究外源氨氮在该系统的质量平衡, 旨为推广绿狐藻湿地在废水处理中应用提供科学依据。

1 材料与方法

1.1 试验材料

供试植物绿狐尾藻采自长沙县金井镇野外生态沟渠。试验前, 选取长势较一致的植株, 剪取顶端20 cm, 在清水中预培养1周。供试水为人工配置的高氨氮营养液, 其氨氮由纯度为99.5%的硫酸铵提供。湿地基质为混合均匀的风干过筛水稻土, 其土壤总氮(TN) 含量为1.86 g· kg^-1, 总磷(TP)含量0.83 g· kg^-1, 有机碳含量21.93 g· kg^-1, pH为6.3, 沙土、粉土、粘土含量分别为32.6%、41.1%、26.3%。

1.2 试验设计

该试验在玻璃温室内进行, 试验时间为2013年8月14日至9月11日。试验期间, 温室内的气温为18.8~37.4 ° C。选用透光钢化玻璃箱(长50 cm× 宽40 cm× 高50 cm)作为小型人工湿地装置, 构建表面流人工湿地。每个装置加入20 kg基质土, 土层为10 cm。将选取的绿狐尾藻植株移入湿地装置, 植物密度为500株· m^-2。为了使植物适应湿地环境, 先在清水中预培养1周。将清水完全排出后, 加入15 L高氨氮水, 水深为5 cm。试验共设置3个污染负荷的处理, 即含N $\begin{matrix} {H_{4}}^{+} \end{matrix}$ -N浓度分别为0、200和400 mg· L^-1, 每个处理3个重复, 共9个装置。为了补充蒸发造成的水量损失, 每次水样采集的前一天加入蒸馏水, 保持湿地的水深为5 cm。

1.3 样品采集与分析

1.3.1 水样采集水样采集时间是0、1、4、7、10、14、17、21、25 和28 d。水样过0.45 μ m孔径滤膜后, 直接用流动分析仪(Fir-5000)测定铵态氮(N $\begin{matrix} {H_{4}}^{+} \end{matrix}$ -N)、硝态氮(N $\begin{matrix} {O_{3}}^{-} \end{matrix}$ -N)浓度; 采用碱性过硫酸钾消解后用流动分析仪(Fir-5000)测定总氮(TN)浓度^[19]。

1.3.2 底泥样品采集在0、1、7、14、21、28 d用圆柱形采样器采集底泥样, 将根系、石子等杂质去除, 然后混均分装, 放入-20 ℃冰箱保存待测。其中, 鲜样用2 mol· L^-1 KCl溶液浸提后, 用流动分析仪(Fir-5000)测定底泥N $\begin{matrix} {H_{4}}^{+} \end{matrix}$ -N和N $\begin{matrix} {O_{3}}^{-} \end{matrix}$ -N; 风干样品磨碎过筛(0.25 mm)后, 用半微量开氏法(GB7173-87)测定TN含量^[19]。

1.3.3 植物样品采集在1、4、7、10、14、17、21、25、28 d, 用直尺分别量取各处理植株的株长。在试验的0和28 d, 采集绿狐尾藻植株样品。样品带回实验室后, 用蒸馏水清洗, 待晾干后, 经105 ℃杀青30 min后, 放置70 ℃烘箱烘干至恒重, 并计算其生物量。将烘干植物样磨碎, 过0.250 mm孔径筛, 装入自封袋中保存。植物样品中的TN经浓硫酸-过氧化氢消解后, 用流动分析仪(Fir-5000)测定其氮浓度。

1.4 数据统计

氮质量平衡法可用于评估湿地系统中的氮去除途径及其贡献率^[20]。在人工湿地系统中, 植物吸收、底泥吸附、氨挥发和微生物硝化反硝化是铵态氮去除的主要途径。植物吸收氮量由鲜重乘以单位鲜重的植物全氮含量得出, 底泥吸附氮量由鲜重乘以底泥含氮量得出, 水体氮量由水样总氮浓度乘以水体积得出。基于以上内容, 由微生物硝化反硝化作用去除的氮量可由以下公式推算得出:

N=I-F-P-F-S-V.

式中:N为微生物硝化反硝化去除的氮量; I为废水中的初始氮量(g); F为试验结束时废水中残留的氮量(g); P为植物吸收的氮量(g); S为底泥中累积的氮量(g); V为氨挥发的氮量(g), 由于试验期间废水中pH在5.59~7.43, 远低于氨挥发所需的pH 8.0^[21], 因此, 本研究中氨挥发损失的氮量可忽略不计。

各部分氮质量计算方法:进水总氮量和水体残留总氮量直接用培养液体积与试验前后浓度相乘得出; 由于添加自配溶液不含有机氮, 所以近似认为底泥吸附氮增量等于铵态氮、硝态氮增量的和; 绿狐尾藻吸收量为植物鲜重增量乘以干鲜比再乘以植物全氮含量得出。

I=V_w× C_w;

F=V_w× C_f;

P=M₁× C_p;

S=M₂× C_s.

式中:V_w为水体积(L); C_w为试验开始时的水体总氮浓度(mg· L^-1); C_f为试验结束时的水体总氮浓度(mg· L^-1); M₁为植物收获鲜重(g); C_p为植物全氮含量(mg· kg^-1); M₂为植物收获鲜重(g); C_s为底泥全氮含量(mg· kg^-1)。

2 结果

2.1 水体TN及NH₄⁺-N、NO₃^--N的去除效果

28 d后200、400 mg· L^-1 N $\begin{matrix} {H_{4}}^{+} \end{matrix}$ -N处理的水体TN去除率分别为86.1%和77.7%(图1), N $\begin{matrix} {H_{4}}^{+} \end{matrix}$ -N去除率分别为89.8%和78.8%(图1)。其中, 0-7 d的TN及N $\begin{matrix} {H_{4}}^{+} \end{matrix}$ -N浓度迅速降低, 7 d后降低速度减缓。200 mg· L^-1处理的TN浓度, 7 d下降为初始浓度的55.4%, 28 d下降为16.3%; 400 mg· L^-1处理的TN浓度, 7 d下降为初始浓度的62.2%, 28 d下降为25.8%。0-7 d, 200和400 mg· L^-1处理减少的水体TN浓度占0-28 d TN浓度减少量的60.8%和50.9%。其中0-1 d去除速率最高, 两个处理在处理1 d时的处理率分别达到73.8%和69.0%, 有26.2%和31.0%的水体TN在0-1 d被去除。

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	图1 水体总氮、铵态氮、硝态氮浓度的变化Fig.1 Changes in the concentrations of ammonium nitrogen total nitrogen and nitrate nitrogen in water

0-28 d内, 200和400 mg· L^-1处理的水体N $\begin{matrix} {O_{3}}^{-} \end{matrix}$ -N浓度先升高后降低, 分别在14和7 d出现最大值, 200 mg· L^-1处理N $\begin{matrix} {O_{3}}^{-} \end{matrix}$ -N浓度达到0.9 mg· L^-1, 400 mg· L^-1处理N $\begin{matrix} {O_{3}}^{-} \end{matrix}$ -N浓度达到1.1 mg· L^-1(图1)。

2.2 底泥NH₄⁺-N、NO₃^--N含量随时间的变化

200和400 mg· L^-1处理, 底泥N $\begin{matrix} {H_{4}}^{+} \end{matrix}$ -N含量0-7 d表现为先升后降, 在7-14 d底泥N $\begin{matrix} {H_{4}}^{+} \end{matrix}$ -N含量有所升高, 14 d之后含量变化趋于平缓(图2)。在14-28 d这一阶段, 200和400 mg· L^-1处理中底泥N $\begin{matrix} {H_{4}}^{+} \end{matrix}$ -N含量分别为19.3~29.5和80.3~94.5 mg· kg^-1, 是原底泥背景值(12.0 mg· kg^-1)的1.6~2.5倍和6.7~7.9倍。

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	图2 底泥铵态氮和硝态氮浓度的变化Fig.2 Changes in the concentrations of ammonium nitrogen and nitrate nitrogen in sediments

200 mg· L^-1处理中N $\begin{matrix} {O_{3}}^{-} \end{matrix}$ -N含量在0-14 d上升速率先快[0-1 d速率为22.8 mg· (kg· d)^-1]后慢[1-7 d速率为4.0 mg· (kg· d)^-1], 400 mg· L^-1处理中N $\begin{matrix} {O_{3}}^{-} \end{matrix}$ -N含量0-1 d急剧上升[速率为24.0 mg· (kg· d)^-1], 然后1-7 d逐渐稳定[速率为0.7 mg· (kg· d)^-1], 1-7 d两个处理上升速率差异明显(图2)。7-14 d, N $\begin{matrix} {O_{3}}^{-} \end{matrix}$ -N含量逐渐增至峰值, 200和400 mg· L^-1处理分别达到53.7和31.5 mg· kg^-1。0 mg· L^-1处理在0-1 d也出现波动, N $\begin{matrix} {O_{3}}^{-} \end{matrix}$ -N含量在处理1 d时达到16.4 mg· kg^-1, 随后降低至小于1.0 mg· kg^-1。

2.3 绿狐尾藻全氮含量及株长增长

经过28 d的培养, 绿狐尾藻全氮含量及植株株长明显增加。试验前后, 0、200、400 mg· L^-1处理植物的鲜重分别为211.3、397.3和345.0 g。200 mg· L^-1处理的全氮含量及植株株长增加量最大, 增加量分别为22.3 mg· kg^-1和44.3 cm, 400 mg· L^-1处理次之, 空白对照最低, 其中绿狐尾藻在400 mg· L^-1处理培养下28 d生物量低于200 mg· L^-1处理, 全氮含量少3.5 mg· kg^-1, 植株株长少7.7 cm(图3)。可见, 一定铵态氮浓度有利于绿狐尾藻的生长, 但铵态氮含量过高, 反而会影响植物生长。

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	图3 绿狐尾藻全氮含量和植株株长的变化Fig.3 Changes in plant total nitrogen and plant length of Myriophyllum elatinoides

2.4 氮质量平衡计算

28 d后, 200和400 mg· L^-1处理中, 14.0%和22.3%的外源N $\begin{matrix} {H_{4}}^{+} \end{matrix}$ -N成为水体残留氮, 14.7%和30.2%的外源N $\begin{matrix} {H_{4}}^{+} \end{matrix}$ -N转化为底泥N $\begin{matrix} {H_{4}}^{+} \end{matrix}$ -N, 25.3%和11%的外源N $\begin{matrix} {H_{4}}^{+} \end{matrix}$ -N转化为底泥N $\begin{matrix} {O_{3}}^{-} \end{matrix}$ -N, 29.7%和12.7%的外源N $\begin{matrix} {H_{4}}^{+} \end{matrix}$ -N被绿狐尾藻植物吸收利用, 16.3%和22.8%的外源N $\begin{matrix} {H_{4}}^{+} \end{matrix}$ -N最终以硝化反硝化途径去除(表1)。可见, 植物吸收在氮去除中贡献较大, 尤其在200 mg· L^-1处理下, 绿狐尾藻的种植有利于水体氮污染的净化。

表1 试验系统在试验28 d后的氮质量平衡 Table 1 The total amount of nitrogen of all parts of the system after 28 days test

指标 Parameter	N $\begin{matrix} {H_{4}}^{+} \end{matrix}$ -N/mg· L^-1
指标 Parameter	0	200	400
0 d进水总氮量Total nitrogen content at 0 d/g	0.00	3.00	6.00
水体残留总氮量Total nitrogen content in residual water/g	0.03	0.42(14.0%)	1.34(22.3%)
底泥吸附氮增量Nitrogen increment absorbed by sediment/g	-0.25	1.20(40.0%)	2.47(41.2%)
绿狐尾藻吸收氮量Nitrogen uptaken by Myriophyllum elatinoides/g	0.18	0.89(29.7%)	0.76(12.7%)
硝化反硝化去除氮量N removal through nitrification and denitrification/g	0.04	0.49(16.3%)	1.43(22.8%)

Note: Data in bracket is total nitrogen variation as a percentage of total nitrogen in different substrates of water.

注:括号里数据是不同基质中总氮变化量占进水总氮量的百分比。

表1 试验系统在试验28 d后的氮质量平衡 Table 1 The total amount of nitrogen of all parts of the system after 28 days test

3 讨论

28 d的试验过程中, 0 mg· L^-1处理的绿狐尾藻生长利用的氮全部来自底泥N $\begin{matrix} {H_{4}}^{+} \end{matrix}$ -N(表1、图2), 说明绿狐尾藻优先利用底泥N $\begin{matrix} {H_{4}}^{+} \end{matrix}$ -N, 而底泥初始N $\begin{matrix} {H_{4}}^{+} \end{matrix}$ -N没有转化为N $\begin{matrix} {O_{3}}^{-} \end{matrix}$ -N的趋势^{[22, 23]}。两个处理的植物吸收氮的总量跟浓度关系不大^[24], 区别也不大, 植物吸收氮量分别为0.89和0.76 g。这说明, 0-28 d, 400 mg· L^-1处理中添加的多余的N $\begin{matrix} {H_{4}}^{+} \end{matrix}$ -N并没有被植物吸收^[25]。

在只添加外源N $\begin{matrix} {H_{4}}^{+} \end{matrix}$ -N的条件下, 底泥N $\begin{matrix} {H_{4}}^{+} \end{matrix}$ -N和N $\begin{matrix} {O_{3}}^{-} \end{matrix}$ -N含量的增加是底泥吸附和硝化共同作用的结果^[26]。底泥N $\begin{matrix} {H_{4}}^{+} \end{matrix}$ -N含量在0-1 d上升, 吸附起主要作用; 1-7 d底泥N $\begin{matrix} {H_{4}}^{+} \end{matrix}$ -N浓度下降, 这是底泥N $\begin{matrix} {H_{4}}^{+} \end{matrix}$ -N吸附和底泥内部硝化共同作用产生的结果, 在这一阶段, 硝化作用较强, N $\begin{matrix} {H_{4}}^{+} \end{matrix}$ -N转化为N $\begin{matrix} {O_{3}}^{-} \end{matrix}$ -N^[27]。7-14 d, 受制于氧气浓度, 硝化作用放缓, 底泥N $\begin{matrix} {H_{4}}^{+} \end{matrix}$ -N含量又有上升。0-1 d底泥N $\begin{matrix} {O_{3}}^{-} \end{matrix}$ -N含量显著上升, 硝化作用明显, 1-14 d底泥N $\begin{matrix} {O_{3}}^{-} \end{matrix}$ -N含量增速逐渐降低, 可能的原因是0-1 d底泥氧气消耗得不到及时补给供应, 硝化作用放缓, 同时反硝化作用也开始消耗硝化作用产生的N $\begin{matrix} {O_{3}}^{-} \end{matrix}$ -N。14-28 d, 此阶段水和底泥的氮浓度均呈缓慢下降趋势, 说明水体、底泥和绿狐尾藻之间的氮流动达到与空白对照处理相似的较稳定的状态^[21]。焦立新等^[28]研究沉水植物穗花狐尾藻(M. spicatum)对高浓度N $\begin{matrix} {H_{4}}^{+} \end{matrix}$ -N(通过底泥释放)抑制作用时发现, 上覆水N $\begin{matrix} {O_{3}}^{-} \end{matrix}$ -N有一定程度升高, 达到7.26~9.31 mg· L^-1, 相比之下, 沉积物底泥N $\begin{matrix} {O_{3}}^{-} \end{matrix}$ -N浓度为2.60~16.01 mg· L^-1, 沉积物间隙水N $\begin{matrix} {O_{3}}^{-} \end{matrix}$ -N浓度为0.71~0.88 mg· L^-1, 说明硝化作用主要发生在上覆水。水深方面, 有研究达到了1 m^[28], 深水条件下不利于水体复氧, 同时本研究底泥沉积物厚度与上覆水深度比例为2:1(上述研究比例为1:4)便于外界空气向水体富氧, 加上试验植物向水体较强的泌氧作用, 本研究浅水条件更有利于水体N $\begin{matrix} {H_{4}}^{+} \end{matrix}$ -N的硝化作用。

高浓度N $\begin{matrix} {H_{4}}^{+} \end{matrix}$ -N水体进入绿狐尾藻湿地系统后, 对植物生长产生了抑制作用, 400 mg· L^-1处理植物株长和全氮浓度均低于200 mg· L^-1处理, 但均高于添加0 mg· L^-1 N $\begin{matrix} {H_{4}}^{+} \end{matrix}$ -N处理。潘琦等^[29]在研究苦草(Vallisneria natans)和黑藻(Hydrilla verticillata)对水体中高浓度N $\begin{matrix} {O_{3}}^{-} \end{matrix}$ -N抑制作用时得出, 在其3个处理浓度范围的植物生长情况, 低浓度和高浓度均对植物生长不利, 而中浓度最适, 在水中只有高浓度N $\begin{matrix} {O_{3}}^{-} \end{matrix}$ -N条件下, 才不利于植物生长。本研究中, 在去除外源添加高浓度N $\begin{matrix} {H_{4}}^{+} \end{matrix}$ -N时, 产生的N $\begin{matrix} {O_{3}}^{-} \end{matrix}$ -N浓度最大值不超过1.2 mg· L^-1, 不足以抑制绿狐尾藻的生长。同时, 在高浓度N $\begin{matrix} {H_{4}}^{+} \end{matrix}$ -N废水处理下, 由于植物吸收、微生物硝化-反硝化作用、底泥吸附等途径能较快地去除N $\begin{matrix} {H_{4}}^{+} \end{matrix}$ -N污染, 减少了其对绿狐尾藻生长的胁迫作用。上述结果表明, 绿狐尾藻可以耐受高浓度N $\begin{matrix} {H_{4}}^{+} \end{matrix}$ -N。

4 结论

室内绿狐尾藻湿地系统对高N $\begin{matrix} {H_{4}}^{+} \end{matrix}$ -N水体的处理效果明显, 其去除率可达89.8%。

不同浓度N $\begin{matrix} {H_{4}}^{+} \end{matrix}$ -N处理的绿狐尾藻的氮含量显著增加, 但400 mg· L^-1处理中添加的多余的N $\begin{matrix} {H_{4}}^{+} \end{matrix}$ -N并没有被植物利用, 说明绿狐尾藻对的吸收利用有一定的限度, 绿狐尾藻植物吸收氮量只能达到总进水氮量的12.7%~29.7%。

绿狐尾藻湿地对于高浓度N $\begin{matrix} {H_{4}}^{+} \end{matrix}$ -N水体具有潜在的N $\begin{matrix} {H_{4}}^{+} \end{matrix}$ -N消解能力, 是因为湿地微生物的硝化反硝化作用, 且高浓度N $\begin{matrix} {H_{4}}^{+} \end{matrix}$ -N水体处理中22.8%的N $\begin{matrix} {H_{4}}^{+} \end{matrix}$ -N最终以硝化反硝化途径去除。

The authors have declared that no competing interests exist.

参考文献

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2010

0.0

... 近年来,随着工业发展和养殖业的集约化,高氨氮废水排放造成了严重的环境问题^[1] ...

2010

0.0

... 氮引起的地表水、地下水污染,已对农业、渔业等多个行业造成危害,已威胁到人们的健康安全^[2] ...

1995

0.0

... 常用的氨氮废水处理方法有厌氧/好氧工艺(A/O)、活性污泥法(SBR)、膜生物反应器(MBR)、氧化沟、人工湿地等^[3,4] ...

2004

0.0

... 常用的氨氮废水处理方法有厌氧/好氧工艺(A/O)、活性污泥法(SBR)、膜生物反应器(MBR)、氧化沟、人工湿地等^[3,4] ...

1995

0.0

... 与其它处理工艺相比,人工湿地是一种简单有效、价格低廉的处理技术,已广泛用于处理农业、工业、矿山废水和生活污水^[5,6,7] ...

1996

0.0

... 与其它处理工艺相比,人工湿地是一种简单有效、价格低廉的处理技术,已广泛用于处理农业、工业、矿山废水和生活污水^[5,6,7] ...

2009

0.0

... 与其它处理工艺相比,人工湿地是一种简单有效、价格低廉的处理技术,已广泛用于处理农业、工业、矿山废水和生活污水^[5,6,7] ...

2009

0.0

... 在人工湿地中,氨氮去除的主要途径有植物吸收、基质吸附、氨挥发和微生物硝化反硝化等^[8,9] ...

2000

0.0

... 在人工湿地中,氨氮去除的主要途径有植物吸收、基质吸附、氨挥发和微生物硝化反硝化等^[8,9] ...

2007

0.0

徐红灯, 席北斗, 王京刚, 蔡洋. 水生植物对农田排水沟渠中氮、磷的截留效应. 环境科学研究, 2007, 20(2): 84-88.

Xu H

, Xi B

, Wang J

, Cai

Study on the interception of nitrogen and phosphorus by macrophyte in agriculture drainage ditch.

Research of Environmental Sciences, 2007, 20(2): 84-88. (in Chinese)

摘　要：为有效阻控农田土壤流失氮、磷通过沟渠进入水体，通过动态模拟实验研究对比不同排水沟渠对农田流失氮、磷的截留作用，同时通过静态模拟实验重点探讨了水生植物对氮、磷在水-沉积物-水生植物这一微观系统中的截留机理。结果表明，沟渠中的水生植物茭白和菖蒲对氮、磷的截留和转化有明显的促进作用；水生植物的存在可以加速氮、磷界面交换和传递，从而使上覆水中氮、

... 除植物本身对氮素直接吸收外,水生植物的存在还可改变基质的理化特性、提高系统中溶解氧含量^[10,11],同时,水生植物还可作为先锋植物用于相应重金属污染严重区域^[12,13] ...

2004

0.0

2016

0.0

张华, 康雅茸, 徐春华. 兰州银滩黄河湿地4种植物的光合特性. 草业科学, 2016, 33(4): 622-634.

Zhang

, Kang Y

, Xu C

Photosynthetic characteristics of 4 wild plants in Yintan wetland in Lanzhou section of Yellow River.

Pratacultural Sciences, 2016, 33(4): 622-634. (in Chinese)

The present study analyzed the relationship between photosynthetic characteristics in different growth stages and environmental factors and discussed plant adaption characteristics and mechanism in wetlands based on natural plants of Lythrum salicaria , Phragmites australis , Scirpus triqueter and Acorus calamus ’s growing in Yintan wetland of Lanzhou section of Yellow River. In May 11, the two peaks curve of net photosynthetic rate (P n ) of L. salicaria and P. australis was not obvious and the P n of S. triqueter and A. calamus were relatively stable, the average of P n decreased in the following order: P. australis>L. salicaria>S. triqueter>A. calamus . In August 19, the curves of P n of L. salicaria , P. australis and S. triqueter showed two peaks with significant photosynthetic “midday depression” and the curves of P n of A. calamus was one peak, the average of P n decreased in the following order: P. australis>A. calamus>L. salicaria>S. triqueter . In May 11, photosynthetically active radiation (PAR), atmospheric temperature (T a ), atmospheric CO 2 concentration (C a ), relative humidity (RH), transpiration rate (T r ), stomatal conductance (G s ), intercellular CO 2 concentration (C i ) and water use efficiency (WUE) had positive correlation or significant correlation with the diurnal variation of P n . In August 19, only PAR, C a , T r , G s , WUE and soil moisture had positive correlation or significant correlation with the diurnal variation of P n . In May 11, PAR and WUE had the greatest effects on P n of 4 studied plants, which were the major environmental and physiological factors. In August 19, PAR and T r had the greatest effect on P n of L. salicaria and S. triqueter ’s and PAR and WUE had the greatest effect on P n of P. australis and A. calamus which were the major environmental and physiological factors. Although each factors had different effects, PAR was the main cause of plant photosynthetic physiological characteristics.

本研究以兰州银滩黄河湿地自然生长的千屈菜( Lythrum salicaria )、芦苇( Phragnites awstralis )、藨草( Scirpus triqueter )、菖蒲( Acorus calamus )为研究对象,对4种典型植物生长季不同阶段的光合特性及其与环境因子间的关系进行比较分析,探讨了4种植物对湿地的适应特性和机制。结果表明,1)5月11日千屈菜、芦苇的净光合速率(P n )呈不明显的双峰曲线,藨草和菖蒲的P n 变化较为平稳,日均P n 表现为芦苇>千屈菜>菖蒲>藨草;8月19日,千屈菜、芦苇、藨草的P n 呈双峰曲线,光合“午休”现象明显,菖蒲为单峰曲线,日均P n 表现为芦苇>菖蒲>千屈菜>藨草。2)5月11日,光合有效辐射(PAR)、大气温度(T a )、大气CO 2 浓度(C a )、相对湿度(RH)、蒸腾速率(T r )、气孔导度(G s )、胞间CO 2 浓度(C i )、水分利用效率(WUE)与4种植物P n 的日变化存在不显著、显著( P< 0 . 05)或极显著( P< 0 . 01, P <0.001)的正相关关系;8月19日,PAR、C a 、T r 、G s 、WUE、土壤湿度(SM)与4种植物P n 的日变化存在不显著、显著或极显著的正相关关系;3)5月11日,PAR、C a 、T a 、RH对4种植物的P n 影响较大,是主要的环境生理影响因子;8月19日,PAR、T r 对千屈菜、藨草的P n 影响最大,PAR、WUE对芦苇、菖蒲的P n 影响较大,是主要的环境生理影响因子。尽管各因子对4种植物的光合速率均有不同影响,但PAR是对植物光合生理特性产生影响的根本原因。

2014

0.0

张丽, 彭重华, 王莹雪, 卢思维. 14种植物对土壤重金属的分布、富集及转运特性. 草业科学, 2014, 31(5): 833-838.

Zhang

, Peng Z

, Wang Y

, Lu S

Heavy metal distribution, bioaccumulation and translocation characteristics of fourteen plants.

Pratacultural Sciences, 2014, 31(5): 833-838. (in Chinese)

This paper focused on the distribution, bioaccumulation and translocation of heavy metal from soil to plants. Based on the concentrations of heavy metals, including Cu, Cd, Pb and Zn, determined by atomic absorption spectrophotometry, fourteen typical plants were studied in the Qingshuitang heavy metals polluted area in Zhuzhou. The results showed that these species had promising prospects on repairing combined heavy metals soil pollution. More specifically, the bioconcentration factor and transfer factor about Aristolochia debilis to Cu, Pb, Cd and Zn, Clerodendrum bungei and Sambucus chinensis to Pb, Cd and Zn, Lagedium sibiricum to Pb and Zn, Setaria viridis and Cynanchum auriculatum to Cd and Alternanthera philoxeroides to Cu were all greater than 1. These plants could apply on the heavy metal pollution regions as pioneer plants.

以株洲市清水塘重金属污染工业区14种典型植物为研究对象,采用原子吸收分光光度法测定其Cu、Cd、Pb、Zn 4种重金属含量,研究植物对重金属的分布、富集和转运特性。结果表明,14种植物对修复复合型土壤重金属污染有较好的应用前景。其中,马兜铃( Aristolochia debilis )对Cu、Pb、Cd、Zn,臭牡丹( Clerodendrum bungei)、接骨草(Sambucus chinensis )对Pb、Cd、Zn,山莴苣( Lagedium sibiricum )对Pb、Zn,狗尾草( Setaria viridis)、牛皮消(Cynanchum auriculatum )对Cd,空心莲子草( Alternanthera philoxeroides )对Cu的地上部分富集系数和转运系数都大于1。可将这些植物作为先锋植物用于相应重金属污染严重区域。

2013

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... 然而,水体中氨氮浓度过高,会对水生植物产生一定的毒害作用,并抑制其正常生长^[14] ...

2015

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... 研究表明,绿狐尾藻对高氨氮具有较强的耐受性,可作为生态治理的先锋植物^[15] ...

2013

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王文国, 苏小红, 汤晓玉, 侯远青, 胡启春. 用于农村生活污水处理的常见外来湿地植物的环境风险评估与管理. 生态与农村环境学报, 2013, 29(2): 191-196.

Wang W

, Su X

, Tang X

, Hou Y

, Hu Q

Environmental risk assessment and management of exotic wetland plants used for treatment of rural domestic sewage.

Journal of Ecology and Rural Environment, 2013, 29(2): 191-196. (in Chinese)

Constructed wetlands have been being used more and more extensively in treatment of rural domestic sewage. The plants used in constructed wetlands are mostly alien garden plants, which might pose threats to rural ecological environment. Environmental risks of eight exotic plants used for this purpose were analyzed for comprehensive evaluation, using a modified Australian weeds risk assessment system and a Chinese alien plants invasion risk assessment index system. Eichhornia crassipes and Pistia stratiotes have been defined as invasive plants, which are very risky and should be used sparingly; Myriophyllum aquaticum and Thalia dealbata have a high potential risk of invasion and should be used with caution; Cyperus alternifolius , Canna indica , Pontederia cordata and Cyperus papyrus are relatively lower in invasion risk and may be appropriately used in constructed wetlands. Analysis of the above-mentioned exotic wetland plants, except the first two for suitable distribution shows that all the wetland plants are suitable to grow in South China, where paddy fields, rivers, lakes, reservoirs and fish ponds are extensively distributed. These wetland ecosystems are vulnerable to threats. It is, therefore, essential to intensify the management of constructed wetlands and wetland plants, by adopting measures likes use of native substitutes, site selection, growth management, isolation and re-use of biomass, etc. so as to reduce the risk of exotic wetland plants, to make better use of them in treating rural domestic sewage and to improve ecological environment of the rural areas.

对用于农村生活污水处理的8种常见外来湿地植物的环境风险进行分析，并利用改良的澳大利亚杂草评估系统和国内的外来物种入侵风险指数评估体系进行综合评价。水葫芦（ Eichhornia crassipes ）和大薸（ Pistia stratiotes ）已被界定为入侵植物，风险最大，应该尽量避免使用；粉绿狐尾藻（ Myriophyllum aquaticum ）和再力花（ Thalia dealbata ）具有一定的潜在入侵风险，应该慎用；旱伞草（ Cyperus alternifolius ）、美人蕉（ Canna indica ）、梭鱼草（ Pontederia cordata ）和纸莎草（ Cyperus papyrus ）的风险性相对较低，可以适当地用于人工湿地。利用最大熵（MaxEnt）模型对除水葫芦和大薸以外的上述其他6种外来湿地植物在我国的潜在适生区进行分析的结果表明，这些植物的主要适生区位于我国南方地区。我国南方农村地区分布广泛的稻田、河流、湖库和鱼塘等生态系统极易受到威胁。应加强对人工湿地和湿地植物的管理，从可替代的本土植物、选址、生长管理、隔离和再利用等方面进行管控，降低外来湿地植物的风险，使其更好地应用于农村生活污水的处理，改善农村地区的生态环境。

... 同时相对于大薸(Pistia stratiotes)、凤眼莲(Eichhornia crassipes)等水生植物,具有较小的生态风险^[16] ...

2015

0.0

... 且处理废水的绿狐尾藻净化系统中微生物对沉积物的脱氮发挥重要作用^[17,18],但有关绿狐尾藻湿地对高氨氮废水的去除效率及其主要去除途径的报道不多 ...

2015

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2000

0.0

... 采用碱性过硫酸钾消解后用流动分析仪(Fir-5000)测定总氮(TN)浓度^[19] ...

... 25 mm)后,用半微量开氏法(GB7173-87)测定TN含量^[19] ...

2008

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... 4 数据统计氮质量平衡法可用于评估湿地系统中的氮去除途径及其贡献率^[20] ...

2006

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卢少勇, 金相灿, 余刚. 人工湿地的氮去除机理. 生态学报, 2006, 26(8): 2670-2677.

Lu S

, Jin X

, Yu

Nitrogen removal mechanism of constructed wetland .

Acta Ecologica Sinica, 2006, 26(8): 2670-2677. (in Chinese)

Eutrophication of lakes and aquatic systems deteriorate the ecosystem and economy. The causes and controls of eutrophication have attracted attentions worldwide, including China. Extensive research has been carried out on problems related to eutrophication in China. Nitrogen is one of the major nutriments contributing to the eutrophication in aquatic environments. The external nitrogen load (including point source and nonpoint source) is an important component of the total water-pollutant load. The traditional wastewater treatment technology, which lacks in integrated collection systems, poses excessive investment costs on the control of nonpoint pollution. The constructed wetland is an important technology to reduce the external nitrogen load, especially from the nonpoint source. It is capable of effectively removing nitrogen and handling a high pollutant load; moreover, it is friendly to eco-system and requires low investment costs. Thus the constructed wetland is especially fit for controlling the eutrophication. Illustrating the nitrogen removal mechanisms in constructed wetland has an important meaning on the eutrophication in aquatic systems. The nitrogen removal mechanism in the constructed wetland with a leak-proof layer consists of volatilization, ammonification, nitrification/denitrification, plant uptake, and matrix adsorption, is reviewed in this paper. In a constructed wetland without a leak-proof layer, the nitrogen exchange with the surrounding environments has significant effects on the nitrogen removal rate. Generally, nitrification/denitrification is the major nitrogen removal mechanism in constructed wetlands. Volatilization is insignificant when the pH of the wastewater is less than 7.5. Volatilization is significant when the pH is higher than 9.3. Nitrification/denitrification is the major nitrogen removal mechanism in constructed wetlands treating domestic wastewater. Under low influent loads, suitable climate conditions, and appropriate plant species, the plant-harvest process maybe the major nitrogen removal pathway. Well-managed artificial wetlands usually show a better nitrogen-removing efficiency than do natural wetlands. Sound system designs (e.g., the medium configuration, the arrangement of helophytes, and the opitimization of water distribution and collection) have a direct impact on the nitrogen removal in constructed wetlands. Reasonable operations and maintenances, such as the effective control of the water level, the correct helophyte cultivation, and the sound helophyte harvest can effectively improve the nitrogen removal in a constructed wetland.

湖泊等水环境的富营养化给人类带来诸多损害，如环境、生态和经济等方面的损害。富营养化的原因和控制途径引起了包括中国在内的很多国家的关注。我国针对水环境的富营养化问题开展了大量的工作。氮是引发水环境富营养化的主要营养物之一。外源氮负荷（分点源和非点源两部分）是水环境污染负荷的重要组成部分。传统污水处理技术应用于收集系统欠缺的非点源污染的治理时成本过高。人工湿地是有效削减水环境中外源氮负荷的重要技术手段，在处理非点源污染源带来的氮负荷时更是如此。人工湿地具有氮去除效果好、耐冲击负荷能力强、投资低和生态环境友好等优点。因此人工湿地非常适合于水环境富营养化的防治。阐明人工湿地中氮的去除机理对水环境的富营养化等具有重要的意义。防渗人工湿地的氮去除机理主要包括挥发、氨化、硝化/反硝化、植物摄取和基质吸附。未防渗的人工湿地中，周围水体与人工湿地的氮交换影响着人工湿地中氮的去除。一般情况下，人工湿地中硝化/反硝化是最主要的氮去除机理。pH值小于7.5时，氨挥发可忽略。pH值在9.3以上时，氨挥发很显著。处理生活污水的人工湿地中氮的去除主要是依靠微生物的硝化/反硝化作用。在进水负荷低、气候适宜、植物物种适宜和收割频率与时机适宜的条件下，植物收割可能成为主要的去氮途径。人工合理导向的湿地的氮去除效果通常优于天然湿地。合理的设计（填料的搭配、植物物种的配置以及布水和集水的优化）对人工湿地系统中氮去除的改善有重要影响。合理的运行，如有效的水位控制，正确的植物培育、合理的植物收割等，能有效地改善湿地中的氮去除。

... 0^[21],因此,本研究中氨挥发损失的氮量可忽略不计 ...

... 14-28 d,此阶段水和底泥的氮浓度均呈缓慢下降趋势,说明水体、底泥和绿狐尾藻之间的氮流动达到与空白对照处理相似的较稳定的状态^[21] ...

2010

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李亚娟, 杨俞娟, 张友润, 滕一波, 方萍, 林咸永. 水分状况与供氮水平对土壤可溶性氮素形态变化的影响. 植物营养与肥料学报, 2010, 16(5): 1153-1160.

Li Y

, Yang Y

, Zhang Y

, Teng Y

, Fang

, Lin X

Effects of water condition and nitrogen level on soild issolved nitrogen compounds.

Plant Nutrition and Fertilizer Science, 2010, 16(5): 1153-1160. (in Chinese)

A ventilated incubation experiment was conducted to investigate the dynamic trends of the soil NH + 4 -N, NO 3 - -N and soluble organic nitrogen(SON)contents under different water conditions and nitrogen levels in two paddy soils, Alluvial soil and Purplish clayey soil. During incubating period, the content of NH + 4 -N in the Purplish clayey soil is significantly higher under the waterlogged incubation than that under the watercontrolled incubation, whether nitrogen fertilizer is added or not. However, the content of NH + 4 -N in the Alluvial soil is not obviously enhanced under the waterlogged incubation or nitrogen fertilization, except for being distinctly elevated at the 7th day of the waterlogged incubation with nitrogen fertilizer addition. The NO 3 - -N contents of the two soils are significantly increased under the watercontrolled incubation with or without nitrogen fertilization. Whereas, aforesaid phenomena exhibits during whole incubation period in the alluvial soil but starts from the 21st day of incubation in the Purplish clayey soil. The NO 3 - -N content is significantly increased in the Alluvial soil with nitrogen fertilization under both the watercontrolled condition and waterlogged condition. While, the NO 3 - -N content of the Purplish clayey soil with nitrogen addition is not noticeably increased under the waterlogged condition. The contents of SON in the two soils are gradually increased and reach the highest level during the period of 21th day to 35th day of incubation, and then are rapidly declined to their original levels. On the peak period, the ratio of SON to TSN can reach to 80% in the Alluvial soil and 60% in the Purplish clayey soil, respectively. These results indicate that the nitrification activity in the Alluvial soil is very strong not only under the watercontrolled condition but also under the waterlogged condition. It is, therefore, important to pay much more attention to the NO 3 - -N leaching loss in the Alluvial soil, and the risk of soluble organic nitrogen losses in the two paddy soils during its peak period could not be neglected either.

采用通气培养试验，研究比较了两种水稻土在不同水分和供氮水平下的矿质氮（TMN）和可溶性有机氮（SON）的变化特征。结果表明，加氮处理及淹水培养均显著提高青紫泥的NH + 4 -N含量; 除加氮处理淹水培养第7 d外，潮土NH + 4 -N含量并未因加氮处理或淹水培养而明显升高。无论加氮与否，控水处理显著提高两种土壤的NO 3 - -N含量，其中潮土始见于培养第7 d，青紫泥则始于培养后21 d; 加氮处理可显著提高淹水培养潮土NO 3 - -N含量，却未能提高淹水培养青紫泥NO 3 - -N含量。两种土壤的SON含量从开始培养即逐步升高，至培养2135 d达高峰期，随后急剧下降并回落至基础土样的水平; SON含量高峰期，潮土SON/TSN最高达80%以上，青紫泥也达60%。综上所述，潮土不仅在控水条件下具有很强硝化作用，在淹水条件下的硝化作用也不容忽视，因此氮肥在潮土中以硝态氮的形式流失的风险比青紫泥更值得关注; 在SON含量高峰期，两种土壤的可溶性有机氮的流失风险也应予以重视。

... L^-1处理的绿狐尾藻生长利用的氮全部来自底泥N H4+-N(表1、图2),说明绿狐尾藻优先利用底泥N H4+-N,而底泥初始N H4+-N没有转化为N O3--N的趋势^[22,23] ...

1992

0.0

... L^-1处理的绿狐尾藻生长利用的氮全部来自底泥N H4+-N(表1、图2),说明绿狐尾藻优先利用底泥N H4+-N,而底泥初始N H4+-N没有转化为N O3--N的趋势^[22,23] ...

2003

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童昌华, 杨肖娥, 濮培民. 水生植物控制湖泊底泥营养盐释放的效果与机理. 农业环境科学学报, 2003, 22(6): 673-676.

Tong C

, Yang X

, Pu P

Effects and mechanism of hydrophytes on control of release of nutrient salts in lake sediment. Journal of Agro-Environment Science, 2003, 22(6): 673-676. (in Chinese)

通过人工模拟的方法,进行了用狐尾藻、凤眼莲2种水生植物来控制湖泊底泥营养盐释放的研究.结果表明,水生植物能有效抑制底泥中TN、TP、硝态氮和氨态氮的释放;沉水植物狐尾藻比漂浮植物凤眼莲的效果好.底泥采取物理处理(塑料包被)后在短期内(15～20 d)能暂时控制底泥中营养盐的释放,但不能保持长久,并在随后表现出一定的"补偿效应".物理措施如底泥包被不是控制底泥营养盐释放的有效方法和根本途径,水生植物修复才能有效抑制底泥中营养盐的释放,今后将成为控制底泥中营养盐释放的发展方向.

... 两个处理的植物吸收氮的总量跟浓度关系不大^[24],区别也不大,植物吸收氮量分别为0 ...

2014

0.0

高岩, 马涛, 张振华, 张力, 王岩, 严少华. 不同生长阶段凤眼莲净化不同程度富营养化水体的效果研究. 农业环境科学学报, 2014(12): 2427-2435.

Gao

, Ma

, Zhang Z

, Zhang

, Wang

, Yan S

Nutrient removals from eutrophic water by Eichhornia crassipes at different growth stages. Journal of Agro-Environment Science, 2014(12): 2427-2435. (in Chinese)

The capability of floating macrophyte, water hyacinth( Eichhornia crassipes ), to clean up eutrophic water has been widely recognized, but there is still lack of information on the effect of E. crassipes at different growth stages on nutrient removal from eutrophic water with various concentrations of nitrogen(N) and phosphorous(P). A series of simulated experiments were conducted comparing the efficiency of N and P removals from eutrophic water by E. crassipes at different growth stages. The proportion of N accumulated by E. crassipes to the total dissolved nitrogen(TDN) removal from the water declined as the initial concentrations of N in the water increased. However, E. crassipes at different growth stages showed different efficiencies of TDN removal from the water with the various concentrations of N and P. In water with relatively low concentrations of N and P, the effects of E. crassipes on the removals of TDN and total dissolved phosphorous(TDP) were not significantly different among the different growth stages; whereas in water with relatively high concentrations of N(TDN ~7 mg·L -1 or ~13 mg·L -1 ), the efficiency of TDN removal from the water at the initial phase of the experiments was significantly higher at the early stage of plant growth than the middle and late growth stages, but became closer among the different growth stages as the experiments progressed. In water with TDN levels of ~7 mg·L -1 , the proportion of plant N accumulation to N removals from water was in order of the late growth stage E. crassipes significantly reduced the contents of N and P in sediments. The amount of P assimilated by E. crassipes exceeded the amount of P removed from the water. The contribution of plant assimilation to the removals of TDP was not significantly different among the different stages of plant growth. These results showed that nitrogen assimilation by E. crassipes at the early growth stage contributed greatly to N removals from water; while N removal via the root biological processes was small, and E. crassipes not only removed P from the water, but also assimilated P released from the sediments.

通过模拟实验,比较不同生长阶段凤眼莲对不同程度富营养化水体氮、磷去除效果,研究植株吸收氮、磷能力对去除水体营养盐的贡献,以及对底泥营养盐含量的影响.结果发现随着富营养化水体初始氮浓度增加,不同生长阶段凤眼莲吸收氮量占水体可溶性总氮(TDN)去除量的比例呈现明显下降趋势,但不同生长阶段凤眼莲吸收作用在净化不同浓度氮的效率和贡献方面存在一定差异.在低浓度富营养化水体中,三个生长阶段凤眼莲对水体TDN、TDP去除效果和效率的影响无显著差异.在净化中、高浓度水体氮时(TDN浓度约为7、13 mg·L -1 ),生长初期凤眼莲对水体TDN在实验前期的净化效率明显高于生长后期,而生长中期净化效率最慢,但在实验中、后期各生长阶段凤眼莲净化速率趋于一致.在中等氮浓度水体中(TDN浓度约为7 mg·L -1 ),凤眼莲吸收氮量占水体氮损失量百分比为生长后期<生长中期<生长初期.种植凤眼莲水体中底泥总氮、总磷含量均显著降低;凤眼莲对磷吸收量高出水体可溶性总磷(TDP)损失量,不同生长阶段凤眼莲吸收作用对消减水体磷的贡献无显著差异.综合分析说明生长初期凤眼莲通过主动吸收净化高浓度水体氮的速率最快、贡献最高,而通过凤眼莲根系调节的生物脱氮途径理论上较弱,凤眼莲不仅能够快速去除上覆水体中的磷,而且能够吸收底泥中的磷

... L^-1处理中添加的多余的N H4+-N并没有被植物吸收^[25] ...

1990

0.0

戴树桂, 张明顺, 庄源益. 底泥中氮的主要迁移转化过程及其转化模型的研究. 环境科学学报, 1990(1): 1-9.

Dai S

, Zhang M

, Zhuang Y

Transportation and translocation of nitrogen in sediment. Acta Scientiae Circumstantiae, 1990(1): 1-9. (in Chinese)

The diffusion and the adsorption of NO 8 -N and NH 4 -N and the denr-trification of NO 8 -N in sediment were studied. NH 4 -N diffused cross the interface of water-sediment into the water column while NO 8 -N transferred in another direction.In interstitial water,45 percent of NO 8 -N from overlying water was adsorbed and 30 percent was lost during denitrifica-tion. The denitrification rate constant of NO 8 -N reached its maximum between 7-11 cm of the sediment and the maximum adsorption occurred in the top few centimeters of the sediment. Transport models of NO 8 -N and NH 4 -N in interstitial water were suggested and applied to calculate the amounts of nitrogen transferred cross the interface.

研究了NO 3 - -N,NH 4 + -N在底泥中的扩散、吸附以及NO 3 - -N的反硝化等过程.结果表明,在泥-水界面间,NH 4 + -N主要向上浮水中扩散,NO 3 - -N主要向间隙水中扩散.扩散到间隙水中的NO 3 - -N45％被吸附,30％因反硝化作用而失掉,其反硝化速率常数在7—11cm层最大.氮的吸附速率常数在表层最大.建立了间隙水中NO 3 - -N和NH 4 + -N的转化模型,并计算了氮在泥-水界面间的扩散量,计算结果与实测结果基本相符.

... 在只添加外源N H4+-N的条件下,底泥N H4+-N和N O3--N含量的增加是底泥吸附和硝化共同作用的结果^[26] ...

2008

0.0

孙志高, 刘景双. 湿地土壤的硝化-反硝化作用及影响因素. 土壤通报, 2008, 39(6): 1462-1467.

Sun Z

, Liu J

Nitrification-denitrification and its affecting factors in wetland soil——A review.

Chinese Journal of Soil Science, 2008, 39(6): 1462-1467. (in Chinese)

摘　要：硝化-反硝化作用与土壤的供氮能力及氮气态损失密切相关，其对于湿地氮循环的生态意义重大。综述了湿地土壤硝化-反硝化作用的研究方法、影响因素及模型表征的研究动态。当前湿地土壤硝化-反硝化作用的研究主要集中在净硝化／反硝化能力方面，而模型研究仅停留在一般概念模型和动力学模型的表征上。影响湿地土壤硝化-反硝化作用的因素主要包括温度条件、水分条件、土壤理化性质及生物区系等。鉴于当前湿地土壤硝化一反硝化作用研究内容的不均衡性和不深入性，其在今后研究中应亟需加强的领域包括：（1）硝化-反硝化作用驱动机制；（2）概念模型与应用模型表征；（3）全球变暖、降水改变及碳、氮输入等对硝化-反硝化作用的影响；（4）人类活动对硝化-反硝化作用的影响。

... 1-7 d底泥N H4+-N浓度下降,这是底泥N H4+-N吸附和底泥内部硝化共同作用产生的结果,在这一阶段,硝化作用较强,N H4+-N转化为N O3--N^[27] ...

2009

0.0

焦立新, 王圣瑞, 金相灿. 穗花狐尾藻对铵态氮的生理响应. 应用生态学报, 2009, 20(9): 2283-2288.

Jiao L

, Wang S

, Jin X

Physiological responses of Myriophyllum spicatum to ammonium nitrogen.

Chinese Journal of Applied Ecology, 2009, 20(9): 2283-2288. (in Chinese)

With the sediment applied with 0, 024%, and 048% NH4Cl (treatme nts CK, SN1, and SN2) as the substrate, a greenhouse experiment was conducte d to study the physiological responses of Myriophyllum spicatum to ammonium nitr ogen. The NH4+-N concentration in the sediment, pore-water, and overlying -water ranged in 1235〖KG-*2〗-〖KG-*7〗87032 mg·kg-1, 109〖KG-*2 〗-〖KG-*7〗103605 mg·L-1, and 010〖KG-*2〗-〖KG-*7〗2430 mg·L-1 , respectively. Comparing with those in CK, the plant height, root length, and fresh biomass of M. spicatum in treatments SN1 and SN2 decreased by 15 66% and 5552%, 4572% and 6765%, and 1969% and 8116%, respectively. T he SOD activity in M. spicatum leaves and roots was SN1 peroxidase (POD) and catalase (CAT) activities in the leaves were SN2 The malondialdehyde (MDA) contents of leaves and roots in SN1 and SN2 were increased by 4630% and 8275%, and 1966% and 5519%, respectively. It was suggested that NH4+-N had toxic effects on M. spicatum, and the higher the NH4+-N concentration in sediment, the more obvious the physiological re sponses of M. spicatum exhibited.

在温室内，以原沉积物(CK)和分别添加0.24%与0.48%氯化铵(SN 1 和SN 2 )的沉积物作为底质培养沉水植物，研究了穗花狐尾藻对高浓度铵态氮胁迫的生理响应.结果表明:不同处理沉积物、间隙水和上覆水中铵态氮浓度分别在12.35～870.32 mg·kg -1 、1.09～1036.05 mg·L -1 和0.10～24.30 mg·L -1 ，与CK相比，SN 1 和SN 2 处理的穗花狐尾藻生物量、株高和根长分别降低了19.69%和81.16%、15.66%和55.52%与45.72%和67.65%.不同处理根系和叶片SOD活性均表现为SN 1 2 2 1 1 和SN 2 根系POD和CAT活性则显著高于CK；SN 1 、SN 2 叶片和根系丙二醛(MDA)含量分别比CK提高了46.30%、82.75%和19.66%、55.19%.不同浓度铵态氮对穗花狐尾藻均具有毒害作用，而且铵态氮浓度越高，植物生理响应越明显.

... 焦立新等^[28]研究沉水植物穗花狐尾藻(M ...

... 水深方面,有研究达到了1 m^[28],深水条件下不利于水体复氧,同时本研究底泥沉积物厚度与上覆水深度比例为2:1(上述研究比例为1:4)便于外界空气向水体富氧,加上试验植物向水体较强的泌氧作用,本研究浅水条件更有利于水体N H4+-N的硝化作用 ...

2010

0.0

潘琦, 邹国燕, 宋祥甫. 硝氮胁迫对不同沉水植物生理生长的影响. 上海环境科学, 2010(1): 16-20.

Pan

, Zou G

, Song X

Effects of nitrate-nitrogen stress on the growth and physiological indices of two submerged macrophytes. Shanghai Environmental Sciences, 2010(1): 16-20. (in Chinese)

沉水植物是水生生态系统的初级生产者,对调控生态系统能量的循环和传递,维持水生态系统的结构和功能,都有极为重要的作用.为了解硝态氮浓度对不同种类沉水植物生理生长的综合影响,实验采用6种浓度的硝态氮对苦草和黑藻进行胁迫处理,在实验开始后的6.24 h测定植株抗氧化物酶(SOD、POD、CAT)的活性,并于实验处理7 d后考察植株的叶绿素含量和各项生长指标.结果表明,缺氮条件下苦草和黑藻的SOD、POD反应强烈,40 mg/L下苦草和黑藻的SOD、CAT酶活性几乎无变化;从处理时间上看,苦草总体表现为各浓度处理的SOD、CAT随胁迫时间增加活性上升,POD活性下降;黑藻生理活性表现则相反.胁迫处理7 d后,苦草5 mg/L处理下生物量积累最大,1～20 mg/L内黑藻生物量积累没有差异,苦草的叶绿素、鲜重增量生长指标总体远低于黑藻.研究表明,10 mg/L是苦草能够耐受的最高硝态氮浓度,黑藻在1～20mg/L内均能较好生长;黑藻较苦草对硝态氮胁迫具有更大的耐受性. Abstract： Solution culture method was adopted to study the responses of Vallisneria natans and Hydrilla verticillata to the stress of nitrate-nitrogen (NO_3-N) with six different concentrations.The vitalities of superoxide dismutase (SOD),catalase (CAT) and peroxidase (POD) were surveyed after the plants had been treated for 6 and 24 hours,respectively.The vitalities of SOD and CAT in both species were found to vary in a similar way when NO_3-N was missing,and the vitalities of the three enzymes had little variation even the concentrations of NO_3-N reaching 40 mg/L.After seven day stress treatment,the contents of chlorophyll and other growth indices of Vallisneria natans such as bio-mass were much lower compared with that of Hydrilla verticillata.The results have shown that in terms of NO_3-N concentrations,10 mg/L would be the tolerable limit for Vallisneria natans,while Hydrilla verticillata could be well growing in the range of 1～20 mg/L,i.e.,the latter species was more tolerant of NO_3-N stress than the former one.

... 潘琦等^[29]在研究苦草(Vallisneria natans)和黑藻(Hydrilla verticillata)对水体中高浓度N O3--N抑制作用时得出,在其3个处理浓度范围的植物生长情况,低浓度和高浓度均对植物生长不利,而中浓度最适,在水中只有高浓度N O3--N条件下,才不利于植物生长 ...