ẢNH HƯỞNG CỦA BÓN LÂN LIÊN TỤC CHO SẮN (9 NĂM) TỚI ĐỘ PHÌ ĐẤT DỐC FERRALIC ACRISOLS Ở TỈNH THÁI NGUYÊN

Nguyễn Thế Hùng, Nguyễn Thế Đặng (trang 19-24)

Từ khoá:  ảnh hưởng, bón phân, lân, sắn, độ phì, đất dốc ferralic acrisol, Thái Nguyên

Summary

Effects of long-term P fertilization for cassava on soil fertility of sloping ferralitic acrisols in Thai Nguyen province

P applications in conmbination with one level of 80kg N and 80 kg K₂O for cassava in sloping ferralic acrisols. It did not have considerable effects on soil C, N, K and S but significantly increased total soil P and soil pH. It increased soil extractable P and Mg but decreased soil extractable K. Soil NH_4-N and NO_3-N supply rates extracted by ion exchange membranes in one day decreased with increased P rates but these could not be detected by chemical extraction method