2022年8月20日 星期六
初春马来眼子菜分解对水体和底泥碳、氮和磷积累及释放的影响
Effect of decomposition of Potamogeton malaianus on accumulation and release of carbon, nitrogen and phosphorus in water and sediment at early spring
2014年 第23卷 第2期 页码[80-86]    下载全文[1.1MB]  
摘要

通过实验室模拟初春温度(17 ℃)条件,研究了沉水植物马来眼子菜(Potamogeton malaianus Miq.)分解过程对其有机碳、总氮和总磷的释放,水体和底泥中有机碳、总氮和总磷含量以及水体中铵态氮和硝态氮含量的影响,同时对水体N2 和N2 O 的释放状况进行了分析。结果表明:在70 d 的实验周期内,马来眼子菜分解迅速,至实验结束时植株失重率达到86. 92%,植株中有机碳量、总氮量和总磷量分别较实验初始时降低了88. 51%、88. 93% 和86.63%;底泥中有机碳、总氮和总磷含量分别较实验初始时增加了5. 56%、17. 06%和2. 17%。在马来眼子菜分解过程中,水体中的溶解氧含量和氧化还原电位均较对照明显降低,并呈现在实验初期迅速下降然后逐渐增加并趋于稳定的趋势;水体中的有机碳、总氮、总磷以及铵态氮含量均较对照大幅度增加,并呈现在实验初期迅速上升然后逐渐下降并趋于稳定的趋势;而水体中的硝态氮含量则呈先下降后上升再下降的趋势。水体中N2 和N2 O 释放通量较对照明显增加,且在实验中期N2 和N2 O 释放通量达到峰值。研究结果表明:随时间推移,马来眼子菜向水体释放的磷大部分沉积到底泥中,而氮则部分沉积到底泥中、部分以气体形式(N2 和N2 O)逸出水体。

Abstract

Through laboratory simulation condition of early spring temperature (17℃), effects of decomposing process of submerged plant Potamogeton malaianus Miq. on its release of organic carbon, total nitrogen and total phosphorus, on contents of organic carbon, total nitrogen and total phosphorus in water and sediment and on contents of ammonium nitrogen and nitrate nitrogen in water were studied, and meanwhile emission status of  N2 and N2 O in water were analyzed. The results show that during the experimental period of 70 d, P. malaianus is decayed quickly, its loss weight rate reaches 86. 92% until the end of experiment, and its amounts of organic carbon, total nitrogen and total phosphorus decrease by 88. 51%, 88. 93% and 86. 63% as compared to those at the beginning of experiment, respectively. At the end of experiment, contents of organic carbon, total nitrogen and total phosphorus in sediment increase by 5. 56%, 17. 06% and 2. 17% as compared to those at the beginning of experiment, respectively. During the decomposing process of P. malaianus, both dissolved oxygen content and oxidation-reduction potential in water decrease obviously as compared to the control with the trend of decreasing quickly at the beginning of experiment and then increasing gradually and becoming stable. Contents of organic carbon, total nitrogen, total phosphorus and ammonium nitrogen in water increase greatly as compared to the control with the trend of increasing quickly at the beginning of experiment and then decreasing gradually and becoming stable. While content of nitrate nitrogen in water appears the trend of firstly decreasing and then increasing again decreasing. Emission fluxes of N2 and N2 O in water increase obviously as compared to the control and reach the maximum in the middle of experiment period. It is suggested that with prolonging of time, most phosphorus in water released from P. malaianus run into sediment, while a part of nitrogen runs into sediment and a part of nitrogen runs out of water as the form. of gas (N2 and N2O).

 

关键词马来眼子菜; 分解; 营养成分释放; 水体; 底泥; 初春
Key wordsPotamogeton malaianus Miq.; decomposition; nutrition release; water; sediment; early spring
作者王博, 李法云, 范志平
所在单位辽宁石油化工大学生态环境研究院, 辽宁抚顺113001
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基金项目国家水体污染与治理科技重大专项(2012ZX07505-001); 国家自然科学基金资助项目(40971277)