摘要
为探究高州水库集水区的污染状况,根据2008年污染源的调查结果,利用排污系数法和输出系数法,结合现场资料调查,分别对该地区点源和非点源污染负荷(COD、NH_3-N、TN、TP)进行估算,并应用地理信息系统(GIS)技术对集水区内污染源空间分布特征及来源构成进行分析。结果表明,高州水库集水区内COD、NH_3-N、TN、TP污染物输出总量分别为8 192.83、394.13、1 137.38、94.29 t/a,其中非点源污染COD、NH_3-N、TN、TP输出量为7 114.79、336.91、1 060.21、88.08 t/a,占污染物输出总量的比例分别为87%、85%、93%、93%。COD、TN和TP均以农林种植源排放为主,占总输出量的比例分别为50%、52%、50%。NH_3-N以农村生活源排放为主,占总输出量的比例为63%。在空间分布上,每年不同乡镇单位面积COD、NH_3-N、TN、TP的负荷强度分别为47.08~144.63、2.43~5.24 kg/hm^2、6.70~20.34 kg/hm^2、0.60~1.73 kg/hm^2,其中此4项指标的污染负荷强度均以临近库区的平山镇最高。在来源构成上,集水区各镇COD、NH_3-N、TN、TP污染负荷的70%~94%来源于非点源。为保护高州水库水环境,应将集水区内非点源(农村生活、散养畜禽、农林种植)作为重点控制源,同时根据其空间分布特征进行分区防治,重点防控区域为平山镇。
Gaozhou Reservoir is the only drinking water source of Maoming City, Guangzhou Province, and plays an important role in local social and economic development. The catchment area of Gaozhou Reservoir includes Magui area o , Dapo, Guding, Shenzhen and Pingshan Towns as well as some area of Dongan and Changpo towns, with the f 1 022 km2. In recent years, economic development and changes in agricultural production modes in the catchment area have increased the eutrophication of Gaozhou Reservoir. In the spring of 2009 and 2010, cyanobac- teria blooms threatened drinking water safety. To assess the pollution status in the catchment area, point and non- point sources pollution loading were evaluated and, based on the 2008 pollution source investigation, emission coef- ficients and export coefficients were calculated. Spatial distribution features and sources of pollution were analyzed using GIS. The study supports pollution control and ecological restoration efforts in the Gaozhou Reservoir catch- ment. Point and non-point sources of pollution include chemical oxygen demand （COD） , ammonia nitrogen （NH3- N）, total nitrogen （TN） and total phosphorous （TP）. Point source pollution loading was evaluated using the emis- sion coefficient method and investigation information included industrial wastewater discharge volume in the catch- ment area in 2008 and the pollutant discharge coefficient, urban population and pollutant discharge coefficient of domestic sewage, stock and marketing amounts of livestock and poultry in large scale breeding and the pollutant discharge coefficient of aquaculture wastewater. Non-point source pollution loading was evaluated using the export coefficient method and the investigation information included the rural population, number of poultry, land use of each town and the vegetation cover in the catchment area in 2008. The total pollution loads of COD, NH3-N, TN and TP discharged from the catchment were 8 192.83, 394.13, 1 137.38 and 94.29 t/a, respectively. Among them, non-point source of COD, NH3-N, TN and TP loads were 7 114.79,336.91, 1 060.21 and 88.08 t/a, ac- counting for 87%, 85%, 93% and 93% of total pollution loads, respectively. The pollution loads of COD （50%）, TN（52% ） and TP（50% ） were mainly agricultural non-point source pollution and the discharge load of NH3-N （63%） was primarily rural domestic pollution. The pollution loads of COD, NH3-N, TN and TP in differ- ent towns ranged from 47.08 - 144.63, 2.43 - 5.24, 6.70 - 20.34 and 0.60 - 1.73 kg/hm2, respectively, with the highest pollution loads of COD, NH3-N, TN and TP in Pingshan Town, the town nearest the reservoir. Non- point sources of pollution contributed 70% - 94% of the COD, NH3-N, TN and TP loads among the towns in the catchment area. To conserve the water quality of Gaozhou reservoir, non-point sources of pollution coming from ru- ral domestic, livestock breeding and agriculture should first be reduced. Moreover, the management strategies in different area should be established according to the spatial distribution characteristics of pollution and Pingshan town is the primary area.
出处
《水生态学杂志》
CSCD
北大核心
2017年第3期23-31,共9页
Journal of Hydroecology
基金
环保公益性行业科研专项(201509027)
国家自然科学青年基金(41401115)
广东省科技计划(2014A020216017)
广东省科技计划(2014A040401037)
关键词
高州水库
非点源
污染负荷强度
地理信息系统
Gaozhou Reservoir
non-point source
pollution load intensity
geographic information system
