盐胁迫对3种沉水植物生长的影响

Effect of Salinity Stress on Growth of Three Submerged Plants

为了丰富低盐水域环境修复的生态治理手段,筛选出适合本地低盐水体环境的沉水植物,在室外比较研究了盐度0、5、10、15条件下轮叶黑藻、穗花狐尾藻和篦齿眼子菜3种本土常见沉水植物的生长、成活、叶绿素及水体TN、TP指标变化规律。结果表明:轮叶黑藻不能适应所有盐度水体;穗花狐尾藻和篦齿眼子菜在盐度5、10、15的水体中均能成活,且2种沉水植物在盐度5的水体中相对生长率比在盐度0的水体中高;穗花狐尾藻在盐度10、15水体中相对生长率为负,叶绿素含量下降;篦齿眼子菜只在盐度15的水体相对生长率为负,叶绿素含量下降;3种沉水植物都能减少水体中TN、TP浓度。综上所述,穗花狐尾藻和篦齿眼子菜可以适应低盐度的水体环境,穗花狐尾藻低盐环境下容易种植成活,篦齿眼子菜种植成活后对低盐度适应性更强。

In order to select submerged plants suitable for the local low salinity water environment to enrich the ecological management means of environmental remediation in the low salinity water areas,the growth,survival,chlorophyll of three native submerged plants(namely,Hydrilla verticillata,Myriophyllum spicatum and Potamogeton pectinatus L.)as well as the concentrations of TN and TP in experimental water body were compared and studied outdoors under the conditions of salinity 0,5,10 and 15.The results showed that H.verticillata could not adapt to all experimental salinity water bodies,and M.spicatum and P.pectinatus L.could survive in the water bodies with salinity of 5,10 and 15.The relative growth rate of M.spicatum and P.pectinatus L.in salinity 5 was higher than that in salinity 0.The relative growth rate of the M.spicatum in the water bodies with salinity 10 and 15 was negative,and the chlorophyll content decreased.The relative growth rate of the P.pectinatus L.only appeared negative in the salinity 15,and the chlorophyll content decreased.All the three submerged plants could reduce the concentrations of TN and TP in the water body.To sum up,M.spicatum and P.pectinatus L.could adapt to low salinity water environment,and it was easier for M.spicatum to survive in the low salinity environment,while P.pectinatus L.were more adaptable to low salinity environment after surviving.