盐城潮滩湿地对N、P营养物质的截留效应研究

研究了盐城潮滩芦苇（Phragmites australis）、盐蒿（Artemisia schrenkiana）、互花米草（Spartina alterniflora）和淤泥光滩4种湿地对N、P营养物质的截留效应.在所选取的4种湿地中,分别采集了水、土壤和生物样;水样的总氮（TN）、总磷（TP）用过硫酸氧化还原法测定,土壤和生物样的TN、TP分别用凯氏定N法和钼锑抗比色法测定.研究结果显示,不同污染程度的水源灌溉下的芦苇湿地,其截留N、P的效果差异显著.其中,黄沙港不定期污水灌溉的芦苇湿地每年平均可截留TN 0.095 t/hm^2、TP 0.026 t/hm^2;而采取三灌三排方式用河水灌溉的新洋港芦苇湿地每年可分别截留TN 0.030 t/hm^2、TP 0.001 t/hm^2.比较盐蒿、互花米草和淤泥光滩3种湿地每年对湿地水中N、P的截留效果,淤泥光滩的效果最差,仅截留TN 0.385 kg/hm^2、TP 0.042 kg/hm^2;互花米草效果最好,分别截留TN 220.660 kg/hm^2、TP 36.754 kg/hm^2.尽管互花米草生物量大于芦苇,但其截留效果仍低于芦苇湿地（芦苇1 a收割1次）.

Retention Effect of Wetland for Nitrogen and Phosphorus Nutrients in the Coastal Zone of the Yancheng

Coastal zone is one of the most sensitive regions to global environment change,most of the physical phenomena and ecological process changes took place because of the coastal wetland exploitation and the coastal land use changes.The wetland ecosystem has the function of purifying the nutrition.It is significant to study the coastal wetland changes and its effects on the eco-environment for better understand the regional eco-environment evolvement or global changes.In order to analysis the retention effect of the tidal flat for nitrogen and phosphorus,the indicators,including nitrogen,phosphorus of water samples,surface soil samples,plants and animal samples,were collected from tidal salt marshes which include Phragmites australis marsh,Artemisia schrenkiana marsh, Spartina anglica marsh and silt flat in the Yancheng tidal flat were tested.Total nitrogen(TN) and total phosphorus(TP) concentrations of all the samples were measured with kjeldahl's device and colorimetric method.The results showed that,under irregular irrigation by pollutant water,about 0.095 t of TN,(0.026 t) of TP can be removed from Phragmites australis marsh per hectare per year,which were 3.2 and 18.5 times as the purification efficiency of Phragmites australis marsh by general irrigation with river water,respectively.The difference of the purification efficiency,between Phragmites australis marshes of river water and effluent irrigation,showed that there were great potential purification functions for nutrients of the Phragmites australis wetlands in the tidal flat of the Yancheng. Among the other 3 types' wetlands,the purification efficiency of silt flat for nitrogen,phosphorus was the poorest,the purification rates for TN,TP just were 0.385 kg/hm~(2),0.042 kg/hm~(2) respectively.The best efficiency came from Spartina anglica flat,there were 220.660 kg/hm~(2),36.754 kg/hm~(2) purification rates for TN and TP.Although with the more biomass than the Phragmites australis,the purification efficiency of Spartina anglica flat is poorer.The possible cause is that the Phragmites australis had been harvested once in a year but the Spartina anglica didn't have in this flat,there accumulated more nitrogen,phosphorus and the nutrients had no chance enter global cycle again.