Đề tài Phân hạng đất đai ( land classification ) bài 8

Tom tat De tai Phan hang dat dai ( land classification ) bai 8: ...dinh duong „ Dat co do phi trung binh (7diem) : dat phen it co ham luong dinh duong thap „ Dat co do phi thap (5 diem) : dat phen trung binh phai cai tao moi nuoi trong duoc „ Dat co do phi qua thap (2 diem) : dat phen nhieu, dat lay thut, dat cat rat ngheo dinh duong phai cai tao lau mo... do phi FCC (Fertility Capability Classification) Dai hoc Bac Carolina USA „ Muc do phan vi (categories) : 3 muc do „ Type : sa cau tang mat (topsoil) „ Subtratatype : sa cau tang duoi (subsoil) „ Modifier condition : cac dieu kien bo sung 7YEU TO CHAT DAT 2. He thong phan loai do phi FCC :..., dat bao hoa nuoc >90 ngay/nam „ d (dry) : kho han >90 ngay/nam „ e (exchange) : CEC (Cation exchange capability) thap „ a (aluminium toxic) : Al3+ bao hoa > 60% Al3+ bao hoa (%) = Al3+ x 100 CEC „ h (high acid) : Al3+ bao hoa 10 - 60% „ i : kha nang co dinh P2O5 cao „ v (vertic)...