N、K元素对水葫芦修复水体铯污染的影响

Effects of N,K Elements on Eichhornia crassipes Repairing Cesium Contamination in Water

研究氮肥和钾肥对水葫芦吸收富集水体^(137)Cs的影响,能够为铯污染水体的植物修复提供方法参考。设计铯污染浓度为0.5、5和50 mg/L,每个铯浓度下,N和K的使用量分别为0、0.5和5 mg/L,3次重复。研究不同铯污染水体中N、K对水葫芦的生物效应(BE)和吸收转移铯的影响情况。结果表明:(1)施用N、K肥对水葫芦不同生物性状有不同影响,这与铯污染浓度、N、K肥施用量有一定关系。(2)单独施用N肥可增加水葫芦干重,单独施用K肥会降低干重。(3)施用N肥提高植株铯含量6.53%,施用K肥提高植株铯含量14.46%,N、K配合施用提高植株铯含量33.96%。说明N、K肥无论是单独施用还是配合施用,均能提高植物铯含量,配合施用的效果大于单独施用。因此,在铯污染水体中,适量施用N、K肥可以提高水生植物对铯的清除能力。

It can provide a method for the phytoremediation of cesium contamination of water to analyze the effects of N,K fertilizer on Eichhornia crassipes absorbing and accumulating 137^Cs in water. Cesium contamination concentration was set as 0.5,5 and 50 mg/L,and corresponding to the use of N and K as 0,0.5 and 5 mg/L respectively,with three duplications aiming to study the biological effects of N,K elements on Eichhornia crassipes and absorption and transfer of cesium in different cesium contaminations water. The results showed that application of N and K fertilizer has different effects on different biological characteristics of Eichhornia crassipes. The dry weight of Eichhornia crassipes increases by adding N fertilizer solely;while it decreases by adding K fertilizer only. The cesium content in plant is increased by 6.53 % by the application of N fertilizer,14.46% by the application of K fertilizer,and 33.96% by combining N and K fertilizer together,indicating that whether N,K fertilizer are used separately or combined together,the two fertilizers can increase the cesium content in plant,and the effect is greater when N,K fertilizer are combined together. Therefore,suitable amount of N and K fertilizer can improve the removal ability of aquatic plants for cesium.