银川平原水葫芦·大薸引种栽培及水体氮磷去除研究

Research on Introduction and Cultivation of Eichhornia crassipes and Pistia stratiotes in Yinchuan Plain and the Removal of Nitrogen and Phosphorus in Water

通过在中温带区域(宁夏银川)设置不同浓度梯度水体处理引进栽种水葫芦和大薸,探寻其中后期生长特征以及利用对氮、磷等营养物质的强吸收作用,解决农田退水富含高氮、高磷等营养物质问题。结果表明,水葫芦、大薸喜高浓度营养元素的生长条件,在高浓度(T4、C4)处理条件下生长最好。水葫芦、大薸对于水体氮磷去除效果显著,对水体氮去除率最高可达84.54%、81.55%;对水体磷去除率最高可达99.17%、98.66%。植物死亡枝体腐烂后,体内氮磷元素会返还水体,应在生长放缓时期及时收割。总磷、溶解氧和pH是影响水葫芦生长存活的关键环境因子;除溶解氧因子外,大薸对其余水质指标均响应显著,与总氮、瞬时水温和总氮相关性强。两者长势良好,夏季能适应中温带区域(宁夏银川)气候,解决农田退水富含高氮、高磷等营养物质问题具有可行性。

Eichhornia crassipes and Pistia stratiotes were introduced and planted in the mid-temperate region(Yinchuan,Ningxia)by setting different concentration gradients for water treatment.Exploring the growth characteristics in the middle and late stages and using the strong absorption of nitrogen,phosphorus and other nutrients to solve the problem of high nitrogen,high phosphorus and other nutrients in farmland dewatering.The results showed that,Eichhornia crassipes and Pistia stratiotes like the growth conditions of high concentrations of nutrient elements,and the best growth conditions were treated with high concentrations(T4,C4).Eichhornia crassipes and Pistia stratiotes have a significant effect on the removal of nitrogen and phosphorus in water,and the removal rate of nitrogen in water can reach 84.54%and 81.55%;the removal rate of phosphorus in water can reach 99.17%and 98.66%.After the dead branches of the plants rot,the nitrogen and phosphorus elements in the body will return to the water body,and they should be harvested in time when the growth slows down.Total phosphorus,dissolved oxygen and pH are the key environmental factors affecting the growth and survival of Eichhornia crassipes.Except for the dissolved oxygen factor,Pistia stratiotes responded significantly to other water quality indicators,and had a strong correlation with total nitrogen,instantaneous water temperature and total nitrogen.Both of them grow well and can adapt to the climate of the mid-temperate region(Yinchuan,Ningxia)in summer,and it is feasible to solve the problem that the farmland retreat water is rich in nutrients such as high nitrogen and high phosphorus.