Distribution,migration and purifying effect of cadmium in artificial Avicennia marina wetland system Phosphorus cycling in a simulated wastewater-affected mangrove(Avicennia marina) wetland system Evaluation and construction of wetland ecological network in Qingdao City Comparison on purification effects of Sonneratia apetala and Phragmites communis wetland systems on nitrogen and phosphorus Lead cycling in a simulated wastewater-affected mangrove(Avicennia marina) wetland system ALLOCATION AND CIRCULATION OF PHOSPHORUS IN ARTIFICIAL WASTEWATER WITHIN A SIMULATED MANGROVE WETLAND SYSTEM THE ECOLOGICAL DISTRIBUTIONS OF BACTERIA AND ALGAE IN THE STIMULATING WETLAND SYSTEM