【摘要】 通过对东江东莞段及东莞运河进行连续5个月的水质监测,分析东江和运河水质变化规律,以及运河排涝对东江水质的影响.监测数据表明,雨季东江东莞段DO、高锰酸盐指数、NH4+-N、TP平均浓度分别为6.2、2.4、1.30、0.14 mg.L-1;东莞运河平均浓度分别为3.4、7.2、9.4、0.69 mg.L-1;运河排涝对东江水质造成季节性的污染,以氨氮最为严重,实测高达4.8mg.L-1.采用CE-QUAL-W2模型建立东江河网水动力水质模型,模型结果和实测数据验证吻合,高低水位的平均误差分别为0.16 m和0.09 m,氨氮平均误差为0.13 mg.L-1.在模型验证的基础上计算分析在不同水文条件下运河排涝对河网的水质影响,计算结果表明,中水位排涝流量大,污染带浓度低,为2.6 mg.L-1,排出主要水体时间短,是较好的排放方式.更多还原

【Abstract】 Based on 5-month consecutive in-situ monitoring data,this paper investigated water quality in Dongguan reach of Dongjiang River and Dongguan Canal,and water quality impact in Dongjiang River caused by the canal drainage during the rainy season.It shows that,the average of DO,permanganate index,NH+4-N and TP in the rainy season are 6.2,2.4,1.30 and 0.14 mg·L-1 in Dongjiang River,respectively,and 3.4,7.2,9.4,0.69 mg·L-1 in Dongguan Canal,respectively.The canal drainage will lead to water quality seasonally polluted in Dongjiang River,especially ammonia nitrogen is the key pollution indicator,and the maximum observed is 4.8 mg·L-1.CE-QUAL-W2 model was applied to simulate the hydrodynamics and water quality in Dongjiang River network.The numerical results agree well with the field data.The average errors of high and low water levels are 0.16 m and 0.09 m,respectively,and the average error of ammonia nitrogen is about 0.13 mg·L-1.The model studied the different scenarios of water quality impact in the river network caused by the canal drainage under different hydrological conditions.The numerical results show that when the canal drainage at the median water level,the concentration in the pollutant zone is relatively low,about 2.6 mg·L-1,and the influence time is shorter.It is a suitable way for the canal drainage.更多还原