Nguyễn Công Vinh*, Ngô Đức Minh*
*Viện Thổ nhưỡng Nông hoá Quốc gia
Từ khoá: ảnh hưởng, nước thải, thành phố, tích luỹ, kim loại nặng, đất, cây lúa, Nam Định
Summary
Heavy metal accumulation in the soil and rice affected by re-use waste water from Nam Dinh town
Study caried out in My Loc district where rice is irrigated by waste water from Nam Dinh town in more than 20 years. Results: waste water is rich in organic matter, phosphate, values of DO, COD, BOD is over the accepted level by Vietnam Standard. Content of heavy metals Cu, Pb, Zn, Ni As is under accepted level of TCVN for surface water. However, in waste water site hey are higher than in non-waste water site. Particularly, content of Cd in waste water is 5-32 times higher than in non-waste water (Red River water) and over TCVN from 1.3 to 8 times, even, over standard of FAO/WHO for irrigating water for agriculture.