The Characteristics Of Nitrogen And Phosphorus Distribu Tion And Its Adsorption Desorption In Caohai Wetland,Guizh Ou Province

To reveal the Weining Caohai water and surface sediment of nitrogen and phosphorus distribution characteristics and the rule of surface sediment on the nitrogen and phosphorus adsorption desorption,In September 2014 and in April 2015,use GPS to Caohai water into the surface layer,middle,and water-sediment interface layer to fixedpoint sampling.The corresponding sampling points in surface sediment sampling,at the same time,gathering Caohai basin of the rivers,pH,TDS,EC,DO field test analysis.Determination of total nitrogen and total phosphorus of the water in the lab,chemical extraction method has been applied to the determination of the surface sediment organic matter,nitrogen speciation and phosphorus speciation,analysis of nitrogen and phosphorus in the surface sediment adsorption desorption laws,Based on the above analysis and discussion on this article made the following main conclusions:(1)Duringe submerged plant,the company a weak alkaline pH value,the DO content is high,the EC value is low,the overall reduction environment;In the water plant area show the opposite trend.In water surface layer,middle,and the interface layer,with the increase of water depth,Eh and DO gradually reduce the trend more apparent,EC and pH had no obvious change.(2)Abundant water to the content of total nitrogen,total phosphorus in water are characterized by a water plant area > submerged plant area,with the increase of water depth,from the surface to the interface layer has a tendency to gradually increase.At the same time,grass sea water in abundance,Has a trend to N2(g),and phosphorus in the submerged plant area in HPO42-form existence,H2PO4-form in the water plant area.Caohai are based on nitrogen and phosphorus from sewage and agricultural nonpoint source,the release of the sediment is also one of the source of nitrogen and phosphorus in grass sea water.(3)Produce the average organic matter in the mutagenicity > altogether,in the water plant area > the submerged plant area distribution characteristics.Caohai section sediment total nitrogen and total phosphorus increased with the increase of the depth,the content has a tendency to gradually reduce.(4)Chohai surface sediment phosphorus total nitrogen content in between 2367-13011 mg/kg respectively,the average of 6937 mg/kg;During dry grass sea total nitrogen content is between 2212 ~ 9861 mg/kg,the average is 6405 mg/kg.In the plentiful water season and Caohai sediment nitrogen speciation is mainly not convert nitrogen(NTNN)strong oxidant leaching nitrogen(SOEF-N),ion exchange nitrogen(IEFN-N),weak acid leaching mode(WAEF-N)and alkali leaching nitrogen(SAEF-N)content is less,and the mean are not convert nitrogen(NTN-N)> can convert nitrogen(TTN-N)> strong oxidizer leaching nitrogen(SOEF-N)trend.(5)The plentiful,TP content in the surface sediment in between 316-759 mg/kg,the average content of 520 mg/kg;During dry Caohai TP content in the surface sediment between 234 ~ 812 mg/kg,the average level of 451 mg/kg,the mutagenicity of total phosphorus content is lower than the same period on average.The plentiful and dry Caohai phosphorus mainly Fe/Al phosphorus and organic phosphorus(OP-P),followed by calcium phosphate(Ca-P)and can also square one phosphorus(RSP-P),ion exchange state phosphorus content is very few,on the spatial distribution,organic phosphorus(OPP),inorganic phosphorus(IP-P)and total phosphorus are consistent,other phosphorus had no obvious correlation.(6)With the increase of temperature,the sediment of ammonia nitrogen in water by adsorption has a tendency to increase,the higher the temperature,the greater the adsorption quantity,and total phosphorus in sediment preferred to reduce the trend,the sediment of ammonia nitrogen and total phosphorus in water body to release a quantity to increase,set the temperature range of the experiment,the higher the temperature,to release a quantity is larger;Partial acidic and alkaline can inhibit the adsorption of ammonia nitrogen and phosphorus,promote the release of sediment phosphorus,and inhibit the release of ammonia nitrogen;As the disturbance,the greater the degree of ammonia nitrogen and total phosphorus adsorption and release.