人工污水中的N在模拟秋茄湿地系统中的分配循环及其净化效果

ALLOCATION,CYCLE AND PURGED EFFECTS OF NUTRIENT POLLUTANT N IN ARTIFICIAL WASTEWATER IN SIMULATED KANDELIA CANDEL WETLAND SYSTEM

在温室中建立模拟红树林植物秋茄湿地系统，系统包括１年生秋茄苗、底泥和潮汐海水分别用正常、５倍和１０倍浓度的人工制备的城市污水每周定时、定量对模拟系统污灌２次，持续１年，用以研究营养污染物Ｎ在系统中的分配循环及被净化的效果．结果表明，加入系统中的污水Ｎ主要留存在土壤中，留存在植物体中只有一小部分．４个处理污水浓度组植株中Ｎ元素的周转期依次为４．１年、４．９年、５．３年和４．３年，比２０龄的秋茄群落Ｎ周期７年短，系统对污水Ｎ的净化效果随污水处理浓度增大而增大，有植物系统中，正常、５倍和１０倍浓度污水处理组分别为２３．５０％、７８．０６％和８３．８８％；无植物系统中，对应组分别为２１．６０％、７７．３５％和８２．０１／．

A simulated mangrove wetland was set up in a greenhouse. The system consisted of three subsystems, the one-year old seedlings of Kandelia candel , sediment and tidal water(the artificial seawater cycled as tide by pumping).The artificial wastewater of three different concentrations,namely Cp1,and Cp10 and artifical seawater(control)of 1.5% salinity had been discharged into the wetland in fixed quantity twice a week for a year.The property of Cp1 was similar to that of domestic wastewater while Cp5 and CP10 contained five and ten times of the nutrients and heavy metals found in nitrogen wastewater,respectively. The results showed that the total nitrogen in artificial wastewater discharged to the system remained mainly in soil with a small portion entered into the seedling subsystem. The cycle time of nitrogen uptaken by seedlings was about 5 years.The N purifying rates of the wetland systems for normal,five times and ten times of concentration of artificial wastewater were 23.50%,78. 06%,and 83. 88%, respectively.