Chemical analyses of plant materials
The dried water hyacinth materials, both before and after their application to wastewater treatment, were ground and analyzed for nitrogen, phosphorus and ash contents by the methods recommended by the National Feed Industry Standard Technology Committee (NFISTC), which include the Method for the Determination of Crude Protein in Feedstuffs ( GB/T 6432-1994, PRC), the Determination of Phosphorus in Feed-Spectrophotometry ( GB/T 6437-2002, PRC) and the Method for the Determination of Crude Ash in Feedstuffs ( GB/T 6438-1992, PRC).