云南高原湖滨带3种挺水植物对水体N的净化能力及响应

以云南常见湖滨带挺水植物水葱、芦苇、茭草为待试植物,通过静水培养试验,分析了3种湖滨带挺水植物在TN浓度为10～10.5 mg.L-1污水中的生长特征及其与净化能力的相互关系。研究表明,植物的生长、生理反应和净化能力间有较好的相关性,水葱、茭草和芦苇的相对生长速率分别为0.0023/d、0.0012/d和0.0017/d,水葱株高增长率为茭草的1.4倍,芦苇的1.84倍,水葱的生长量为(干重)3.53 g,为芦苇的1.76倍,茭草的2.22倍;对N的累积能力分别比芦苇和茭草高1.1倍和1.3倍,对氮的同化利用率显著高于芦苇和茭草。水葱、芦苇、茭草对污水氮的净化率分别为86.59%、76.32%和74.83%,对氮的吸收率分别为23.81%、8.55%、11.30%;电导率和MDA比值分别为1.136,2.214和1.413;0.962,1.629和2.06,水葱均表现出较好的净化效果和较强的抗逆性。结果表明,植物对环境的适应及功能的发挥,一方面取决于自身的生物学特性,另一方面受生长环境的影响,环境胁迫导致其生长不良,不能有效发挥其湖滨水体净化功能。

Nitrogen removal ability of three emergent aquatic plants along the plateau lakeside of Yunnan and their response to sewage

Three emergent aquatic plants including Scirpus validus,Phragmites australis and Zizania latifolia,commonly found in Yunnan plateau wetland lakeside were selected to study the purification effect using pot experiments.The biomass,resistance,nitrogen(N) removal and their relationships of the plants were studied under the TN concentrations of 10 15 mg.L 1in the sewage.The results showed that the N removal ability had significant correlation with the plant physiological reaction and growth.The relative growth rates of S.validus,Z.latifolia and P.australis were 0.0023,0.0012 and 0.0017 d 1,respectively.Growth rate in height of S.validus was 1.4 times and 1.84 times higher than that of Z.latifolia and P.australis,respectively.The biomass of S.validus reached 3.53 g,which was 1.76 times and 2.22 times higher than that of P.australis and Z.latifolia,respectively.The N accumulation capacity of S.validus was 1.1 times and 1.3 times larger than that of P.australis and Z.latifolia,respectively,and it also had significantly higher N assimilation efficiency as compared to Z.latifolia and P.australis.For S.validus,P.australis and Z.latifolia,the sewage N removal rates were 86.59%,76.32% and 74.83%;the rates of N uptake were 23.81%,8.55% and 11.30%;the conductivities were 1.136,2.214 and 1.413;and the ratios of MDA were 0.962,1.629 and 2.06.S.validus appeared to be most efficient in both of purification and stress resistance.The result showed that the functioning of plants and their adaptation to environment not only depend on their biological characteristics but also on the growth environment.To apply the aquatic plants to treat the polluted lakes,the compatibility of plant biological characteristics and plant adaptability should be considered;otherwise,the goal of purifying polluted lake waters could not be reached.