Effects of Hg2+, Pb2+ Cd2+ and Cu2+ on the growth and purification capacity of nitrogen and phosphorus of Rhodopseudomonas palustris Inhibitory Effect of Heavy Metal Stress on the Seed Germination of Four Turfgrass Types THE EFFECTS OF LEAD,CADMIUM AND MERCURY IONS ON LDH IN Vicia faba Development of Heavy Metal Ions Detection Biosensors Bacterial Adsorption of Heavy Metal Ions such as Cd2+