氮、磷污染水体中荷花的生态效应和生理响应

Ecological effects and physiological responses of lotus on nitrogen and phosphorus polluted water body

[目的]本文旨在探讨荷花(Nelumbo nucifera)在不同氮、磷浓度污染水体中的生态净化效果和生理响应。[方法]在高[总氮(TN):30 mg·L^(-1);总磷(TP):3 mg·L^(-1)]、中(TN:20 mg·L^(-1);TP:2 mg·L^(-1))和低(TN:10 mg·L^(-1);TP:1 mg·L^(-1))3种不同氮、磷污染水平下,以自来水培养为对照组,测定荷花‘红巨子’的生理指标以及水体和底泥的氮、磷浓度,探究荷花对水体和底泥中氮、磷净化吸收的周期变化和生理响应情况。[结果]中、高氮磷浓度水体会对荷花产生胁迫,胁迫作用随着氮、磷浓度升高而加强,而低氮磷浓度水体对荷花生长有促进作用。随着水质的改善,荷花叶片抗氧化酶活性逐渐接近对照组水平。荷花对氮、磷污染水体和底泥中的TN、TP去除效果显著,其中,处理35 d时荷花对低、中、高氮磷浓度富营养化水体中TN去除率分别为57.34%、73.95%、79.49%,TP去除率分别为84.75%、89.99%、83.69%;对低、中、高氮磷浓度富营养化处理组底泥中TN去除率分别为41.36%、32.37%、33.51%,TP去除率分别为59.19%、80.01%、77.72%。[结论]荷花不仅对水体氮、磷污染和底泥中磷污染具有很好的去除效果,而且具有修复较高氮、磷浓度污染水体的潜力,对高污染氮、磷水体净化具有重要意义。

[Objectives]The aim of this study was to investigate the ecological purification effect and physiological response of lotus(Nelumbo nucifera)in polluted water bodies with different nitrogen and phosphorus concentrations.[Methods]The physiological indexes of lotus‘Hongjuzi’and the water column and substrate nitrogen and phosphorus concentrations were measured at three different nitrogen and phosphorus pollution levels:high[total nitrogen(TN):30 mg·L^(-1);total phosphorus(TP):3 mg·L^(-1)],medium(TN:20 mg·L^(-1);TP:2 mg·L^(-1))and low(TN:10 mg·L^(-1);TP:1 mg·L^(-1)),and the tap water culture was used as the control group,to investigate the cyclic changes and physiological response of lotus to the purifying uptake of nitrogen and phosphorus in the water column and substrate.[Results]Water with medium and high nitrogen and phosphorus concentrations produced stress on N.nucifera,and the stress effect intensified with increasing nitrogen and phosphorus concentrations,while water with low nitrogen and phosphorus concentrations promoted lotus growth.With the improvement of water quality,the antioxidant enzyme activity of lotus leaves gradually approached the level of the control group.The removal of TN and TP from nitrogen and phosphorus polluted water bodies and substrates by lotus was significant,and the removal rates of TN from low,medium and high concentrations of eutrophic water bodies at 35 days of treatment were 57.34%,73.95%and 79.49%,the removal rates of TP were 84.75%,89.99%,83.69%,respectively;the TN removal rates were 41.36%,32.37%and 33.51%,and TP removal rates were 59.19%,80.01%and 77.72%in the substrate for the low,medium and high concentration eutrophication treatment groups,respectively.[Conclusions]N.nucifera not only had a good purification effect on nitrogen and phosphorus pollution in water bodies and phosphorus pollution in the substrate,but also had the ability to remediate water bodies polluted with higher nitrogen and phosphorus concentrations,it was important for the purification of high nitrogen and phosphorus polluted water bodies.