密度和收割对水蕹菜净水效果的影响

通过在水桶试验中设置2种不同处理方式(密度和收割),研究水蕹菜(Ipomoea aquatic Forsk)对富营养水质的净化特性及效果。结果表明:室外培养12 d,高密度组(10 g/L)对NO2-、NO3-、PO32-、TN、TP和Chl-a的平均去除率最高,分别为90.88%、93.98%、98.96%、82.36%、88.89%和89.33%,显著高于对照组(0 g/L);收割有助于刺激植物加速分蘖、促进植物对N、P元素的吸收固定,并改善水体的DO;水蕹菜组织N、P含量在试验前后发生变化,并与生长水体中的N、P浓度呈正相关关系;植物固定对水体中N、P去除的贡献率与植菜密度呈正相关关系,占高密度组水体中TN、TP去除总量的52.05%和40.41%,为试验组水体中N、P去除的主要途径。

Effects of planting density and harvest of Ipomoea aquatic on the purification efficiency of eutrophic pond water

We use two kinds of treatments(different density and harvest) to study the characteristics and effects of eutrophic water purification by Ipomoea aquatica in water bucket.The results show,after 12 days outdoor culture,the removal rate of NO-2、NO-3、PO3-4、TN、TP and Chla in high density group(10 g/L) are 90.88%、93.98%、98.96%、82.36%、88.89% and 89.33%,respectively.It means that the high density group is significantly higher than the control group(0 g/L).Otherwise,harvest will accelerate the tiller,promote absorption of nitrogen and phosphorus,and improve the DO in water.The phosphorus and nitrogen concentration of plant tissue change,it shows positive correlation with the growth of the water body of the phosphorus and nitrogen.It also shows a positive correlation between the nitrogen removal rate and the density of plant,the high density group(10 g/L) of Ipomoea aquatica removed the 52.05% of TN and 40.41% of nitrogen,respectively.