Nguyễn Hữu Thành, Văn Thị Hà
Từ khoá: đặc điểm hoá học, lân, đất phù sa, sông Hồng
Summary
Study on the phosphorus chemical characteristics of eutric fluvisols inside dike of the Red River in Hanoi
Total content of P2O5 at surface horizons was 0.10-0.23% and decreased by depth. Total phosphorus reserve 2.16-5.68tons P2O5/ha. Content of total phosphorus was mainly inorganic phosphorus, occupying 81.20-96.47% of the total phosphorus. Forms of insoluble and ion phosphate have highest rate in the inorganic phosphorus. Content of available phosphorus was not so high, being 2.3-7.3mg/100g soil at surface horizons. P fixation capacity was high and depended on a P dose added to the soil. Fixed amount of P2O5 decreased 24.89-39.69% when added P dose was 20 ppm P.