密云水库水源保护区不同类型村庄生活污水排放特征

Discharge Features of Rural Domestic Wastewater from Different Types of Villages in Water Source Protection Area, Miyun Reservoir, Beijing

密云水库作为北京市重要的水源地，水质状态存在向中等富营养发展的趋势。由于流域村镇生活污水收集处理程度低，已成为影响密云水库水质的污染来源之一。本文选取水源保护区内普通自然村、生态旅游村和镇政府所在村3种典型村庄为研究对象，采用入户调查和采样分析的方法对村庄生活污水的产量、组成、排放系数及季节变化等特征进行研究。结果表明，不同类型村庄的污水的产量和结构不尽相同，旅游村的污水产量远远高于普通村和镇级村。厨余废水、洗浴废水和洗衣废水构成生活污水的主要部分，其中旅游村的污水主要来自养鱼废水。生活污水的产生具有季节性和时段性的特点，旅游村夏秋两季污水产量最高，约为冬春两季的2-4倍；普通村和镇级村夏季污水产量约为其他季节的2-3倍。旅游村的人均生活污水排放系数最高，为118 L·d^-1，是其他类型村人均生活污水排放系数的4-5倍，普通村最低。污水中的总磷（TP）、化学需氧量（COD）和氨氮（NH4^＋-N）指标均较高。COD含量与污水类型密切相关，与村庄类型无明显相关。

Water quality of Miyun Reservoir in Beijing, an important surface drinking water source area, trends to medium eutrophication. Rural domestic wastewater has become one of important pollution sources of Miyun Reservoir, owing to the low level of sewage collection and treatment. Three types of villages in this water source protection area including the ordinary village, eco-tourism village and village where the town government locates were selected to study discharge amount, composition, temporal variation and emission coefficient of rural domestie wastewater by in-door survey and sample analyzing. The results showed that there were different amount of wastewater discharge and structures in different types of villages. The wastewater discharge of eco-tourism village was much higher than other two villages. Kitchen wastewater, bath wastewater and laundry wastewater constituted major parts of rural wastewater. There was a large percentage of wastewater from fishpond in eco-tourism village. The wastewater discharge amount varied from different seasons and period of the daily time, The wastewater discharge amount from coo-tourism villages in summer and autumn were higher, about 2-4 times than that amount in winter and spring. The wastewater discharge from ordinary village and township in summer was 2-3 times than that amount in any other seasons. The per capita wastewater emission coefficient of the eco-tourism village was the highest at 118.06 L· d^-1, which was 4-5 times than that of other two types of villages. The per capita wastewater emission coefficient of the ordinary village was the lowest. The concentration of total phosphorus （TP）, chemical oxygen demand（COD） and ammonia（NH4^＋-N ） were rather higher. The concentration of COD related closely to the type of wastewater, not to the type of village.