NGHIÊN CỨU CÂN BẰNG N, P, K TẠI MỘT SỐ VÙNG THÂM CANH RAU NGOẠI THÀNH HÀ NỘI

Nguyễn Mạnh Khải¹, Phạm Quang Hà², Đặng Thanh Xuân², Nguyễn Thị Huệ², Ingrid Oborn³

¹Khoa Môi trường, Đại học Khoa học Tự nhiên

²Viện Thổ nhưỡng Nông hoá

³Trường Đại học Nông nghiệp Thuỵ Điển

Từ khoá: cân bằng, N, P, K, thâm canh, rau, ngoại thành, Hà Nội

Summary

N, P, K balance at field levels in intensive vegetable farming of Bang b and Phuc Ly village (Hanoi peri-urban)

Results: the main source of element inputs to agricultural land was waste water in Bang B village and animal manure in Phuc Ly. In connection to the field balance we can draw conclusion that the choice of cultivating wet vegetables gives higher inputs of nutrients through water compared to the dry vegetables. Balances showed surplus for N and P. All the K-balances except one (XC-BB) showed deficit. The range of P-balances at farm-gate level is +112 to 432kg/ha/year. Nutrient balances at field level showed N-surplus of 154-910 kg/ha/year, and K that ranged between -133 to 779 kg/ha/year. However, the high N and P surpluses in Phuc Ly and Bang B might indicate a certain risk for N and P losses to the wide environment. That can cause problems with eutrophication of irrigation and drinking waters.