《三种挺水植物抗性生理生态特性研究》由会员分享，可在线阅读，更多相关《三种挺水植物抗性生理生态特性研究（10页珍藏版）》请在金锄头文库上搜索。
1、. As an essential component of most constructed wetlands, emergent hydrophytes play importantEco-physiological characteristics of three emergentmacrophyte species to concentration changes of COD,5101520nitrogen and phosphorus#Sun Ruilian1,2, Liu Jian1*(1. Environment Research Institute, Shandong Uni
2、versity, JiNan 250100;2. Insitute of Ecology and Biodiversity, Shandong University, JiNan 250100)Abstract: Three macrophyte species (Zizania latifolia Turcz., Iris pseudacorus L. and Typha latifoliaL.) were studied in constructed microcosm wetlands in order to compare the ability of hydrophytes inpu
3、rifying simulated polluted river water and to analyze plant responses to oxidative stress induced bychemical oxygen demand (COD), nitrogen and phosphorus. The results showed that plantedmicrocosms were more effective in removing COD, total nitrogen (TN) and total phosphorus (TP) thanunplanted microc
4、osms. Among the three hydrophytes, Z. latifolia was superior for TN removal, while I.pseudacorus units showed the highest TP removal efficiency. However, there was no significantdifference between planted units in COD removal efficiencies. The plasticity of I. pseudacorus was thebest exposed to sewa
5、ge, which was associated with significantly higher SOD and CAT activities withtreatment T1. However, treated with low COD/N/P (T1), the MDA levels of T. latifolia and Z. latifoliawere basically unaffected. In addition, treatment of polluted river water induced enhancement inproline level of three sp
6、ecies. It can be concluded that the antioxidative defence system and free prolineaccumulation were activated but could not resist the oxidative stress in plants exposed to highconcentrations of COD/N/P (160/30/4 mg L-1).Keywords: Emergent macrophyte; Antioxidant enzyme; Nutrient removal; Zizania lat
7、ifolia; Irispseudacorus; Typha latifolia25 1 IntroductionDue to excellent nutrient capturing capacity, low operation cost and low energy demand,constructed wetlands have been used as nutrient sinks or removal systems for polluted river water1roles in facilitating physical and biological processes in
8、 nutrient and organic substance removal. In303540fact, not all emergent macrophytes can tolerate permanent flooding and lower dissolved oxygendue to high COD and biochemical oxygen demand (BOD) loads, and at high concentrations, somenutrients in the aquatic environment due to agricultural run-off, i
9、ndustrial discharge and biologicalwaste decomposition, especially ammonium and phosphate, may become toxic to plant growth.However, for successful growth, the species selected must be able to tolerate permanentwaterlogging, higher nutrient concentrations, lower dissolved oxygen, higher turbidity, an
10、dpotentially toxic contaminants depending on the source of the wastewater.Much previous work on macrophytes has involved plant growth, nutrient and COD removal,nutrient accumulation and translocation, heavy metal removal and accumulation2-4. Only fewstudies have been conducted on physiological toler
11、ance of macrophytes to high nutrient andorganic substance concentrations. The responses of submerged macrophytes to increasedconcentrations of ammonia have been reported by Cao et al.5, Nimptsch and Pflugmacher6, andWang et al.7, who discussed the physiological and biochemical responses to ammonia s
12、tress andthe antioxidative protection mechanisms of macrophytes. Yu and Yang8 studied thephysio-chemical characteristics of seaweed Gracilaria lemaneiformis under high N/PFoundations: Specialized Research Fund for the Doctoral Program of Higher Education (No. 20100131120078),Foundation for National
13、Water Special Project (No. 2012ZX07203-004), National , Excellent Young andMiddle-Aged Scientists of Shandong Province (BS2010SF016) and Independent Innovation Foundation ofShandong University (2012TS039)Brief author introduction:The first auhtor and the corresponding author: Sun Ruilian, (1978-), f
14、emale, doctor,lecturer, phytoremediation. -1-45505560concentrations. Recently, Xu et al.9 reported the physiological responses of emergentmacrophytes Phragmites australis to wastewater with different CODs. However, most currentresearch on physiological tolerance to nutrient stress focuses on submerg
15、ed macrophyte. Studieson the physiological response of emergent macrophytes are still very limited.Among emergent macrophytes, Typha latifolia, Iris pseudacorus and Zizania latifolia Turcz.are common wetland plants that grow widely in tropic and warm regions10. With their highnutrient absorption cap
16、acity, they have been used widely in constructed wetlands around the world.In our previous study on the ability of eight species of emergent plant in purifying polluted riverwater, it has been showed that I. pseudacorus, Z. latifolia and T. latifolia were good choices ineliminating nutrients and organic matter 11. There have been no detailed studies on plant toleranceto organic substance and nutrient stress. Therefore, the main aims of this study wer
