太湖旱地非点源污染定量化研究

采用田间试验方法,研究了太湖地区旱地氮磷向水体排放的年负荷。结果表明,太湖流域典型旱地氮磷向水体迁移的年负荷分别为12.66,4.05 kg/hm2,分别约占年施肥量的5.6%和4.1%。示范区内旱地氮磷向水体迁移的年总量为3.86 t和1.24 t。NO3-—N和PN是氮流失的主要形式,应重点控制NO3-—N和PN的流失;而PP是磷流失的主要形式,占总磷的76%,是控制的重点。氮磷向水体迁移具有明显的季节特征,夏季和秋季为氮磷高负荷季节,6—11月占全年氮磷输出总量的83.4%和79.8%。在当前的非点源污染治理中,应采取有力措施控制农田养分流失。

Quantif ication of Non2point Pollution from Uplands in Taihu Lake Catchment

The released nitrogen and phosphorus by surface runoff from uplands in the Taihu Lake catchment were investigated in a case study. Results showed that each year, about 12.66 kg/hm^2 of nitrogen and 4.05 kg/hm^2 of phosphorus from the uplands in the catchment were discharged into water body, accounting for 5.6 % and 4.1% of annual fertilization, respectively. About 3.86 t of total nitrogen and 1.24 t of total phosphorus from the uplands in the demonstration area were discharged into water body per year. Nitrate-N and PN were the main component part of N loss, which indicates that controlling Nitrate-N and PN loss is the key to controlling non-point pollution. PP was the main component part of phosphorus loss, accounting for 76 % of total phosphorus. Nitrogen and phosphorus loss were obviously characterized by seasonal variation. Summer and autumn were the high load seasons, in which nitrogen and phosphorus loss from June to November accounted for 83.35% and 79.79% of total loads, respectively. We should pay great attention to controlling nutrient loss during farming for non-point pollution control.