茶園小流域からの窒素,リン,CODの排出負荷量の推定

概要

論文の詳細を見る
An investigation on water quality was conducted in a small catchment of a tea field for three years, and runoff loads of total nitrogen (T-N), total phosphorus (T-P) and chemical oxygen demand (COD) were estimated. Runoff quantity was estimated using a water-balance equation. The annual runoff loads of T-N were estimated to be 61.0 kg·ha-1 for the first year, 193 kg·ha-1 for the second year, and 88.1 kg·ha-1 for the third year, and the average load for the three years was 114.1 kg·ha-1. The ratio of the nitrogen load to the amount of applied nitrogen fertilizer was 17.1%, being much lower than in previous studies. The main reason for the low ratio obtained in this study was the lower concentration of nitrogen. The annual runoff loads of T-P and COD were estimated to be 0.68 kg·ha-1 and 59 kg·ha-1, respectively, and both were affected by the flushing effect on rainy days. This result suggests the importance of monitoring of phosphorus and COD as well as nitrogen in upland fields.
社団法人　日本水環境学会の論文
2002-09-10