The Research Of Absorption Property To Nitrogen And Phosphorus With Several Kinds Of Aquatic Plants In Northeast Areas

This thesis has do the research on the absorption of nitrogen and phosphorns nutrition element for three kinds of hydrophytes (Nymphaea alba,calamus and Phragmites australis) under the condition of different nutrition grads in the rice field, and also researched the absorption of nitrogen and phosphorns nutrition element under the condition of different pH. In this experiment we did not only do the research on the absorption of the nutrition element for just one kind of hydrophytes but also plant two. kinds of hydrophytes together to determine the impact of absorption nitrogen and phosphorns nutrition element for plant different hydrophytes together.For research the absorption of nitrogen and phosphorns elements in the simulate conditions of rice field for these three kinds of hudrophyte,we did a simulate experiment in the lab. The results has shown that as the time extend the biomass of hydrophytes has increased. Nymphaea alba has the most increase biomass at the condition of slight stress 24.6g per individual plant, Phragmites australis has the most increase biomass at the condition of moderate and grievous stress 29.18g per individual plant and 18.08g per individual plant.It also has shown that when the nutrition increased in the simulate rice field the ability of absorption has increased too.But the leaves of hydrophytes has turn to yellow and fall off when the water of rice field at a hight consistence of nutrition. It has shown that when the water has a high consistence of nitrogen and phosphorns elements the growth of hydrophytes would be restrainde, it also iduce the descend of nutrition absorption for hydrophytes, thses can be lead to secondary pullution and accelerate the deteriorate of water quality.In the condition of moderate stress these three kinds of hydrophytes has a highter ability of absorption, the removal rate of Phragmites australis for nitrogen and phosphorns element is 78.7% and 96.1%, the removal rate of calamus for nitrogen and phosphorns element is 75.1% and 92.4%, the removal rate of Nymphaea alba for nitrogen and phosphorns element is 70.6% and 90.2%. In the conditions of slight stress and moderate stress the removal rate of Nymphaea alba for nitrogen and phosphorns element is 73.2% and93.3%. The result has shown that in the condition of slight stess Nymphaea alba has a better ability of absorption for nitrogen and phosphorns elements.In the experiment of plant one kind of hydrophytes and plant two kinds of hydrophytes together we found that in the condition of slight stress the nitrogen and phosphorns element removal rate of Nymphaea alba single group is better than Nymphaea alba combination group, but in the moderate and grievous stress the nitrogen and phosphorns element removal rate of Nymphaea alba combination group is better than Nymphaea alba single group. Therefore when disposeal low concentration of nitrogen and phosphorns element of water it can be palnt Nymphaea alba untiary for cecontaminate water. In the conditions of slight stress and moderate stress the removal rate of nitrogen and phosphorns element for calamus combination group is better than single group. The result has shown that when calumus make use of cecontaminate water plant calcmus with other hydrophytes is better than plant calamus single. Compare with the removal rate of nitrogen and phosphorns element for Phragmites anstralis single group and combination group we found that Phragmites australis has a better avsotption of nitrogen and phosphorns element in the water especially in the condition of grievous stress Phragmites australis is the best hydrophyte combination group for absorption of nitrogen and phosphorns element in the water, so we got this conclusion Phragmites australis is the best hydrophytes to decontaminate water when the water has a hight concentration of nitrogen and phosphorns element.In the condition of differenet pH the absorption of nitrogen and phosphorns element for different hydrophytes was significant difference. In the condition of acaid the removal rate of nitrogen and phosphorns element for Nymphaea alba in the water is 71.3% and 90.4%, the removal rate of nitrogen and phosphorns element for calamus in the water is 73.4% and 94.6%, the removal rate of nitrogen and phosphorns element for Phragmites australis in the water is 75.4% and 96%. In the condition of alkalescence the removal rate of nitrogen and phosphorns element for Nymphaea alba in the water is 72.1% and 89.2%, the removal rate of nitrogen and phosphorns element for calamus in the water is 78.9% and 88.8%, the removal rate of nitrogen and phosphorns element for Phragmites australis in the water is 79% and 92.7%. Compare with these conclusions when we make use of hydrophytes to decontaminate sewage alkalescence water body could promote the absorption of nitrogent, and alkalescence water body could restrain the absorbation of nitrogent. But when we make use of hydrophytes to decontaminate sewage acid water body could promote the absorption of nitrogent, and acid water body could restrain the absorbation of nitrogent.