Test Research on the Characteristics of Pollution Boundary Layer in the River Outlet Area of Grand Liao River

By using the meteorological data in the pollution boundary layer which was observed in two ground observation sites:coast and land in the river outlet area of Grand Liao River during January-February in 2007,the daily change characteristics of pollute boundary layer in winter in the area were discussed. The results showed that the pollute boundary layer in the river outlet area of Grand Liao River was affected by the sea and land. In the certain weather condition,maybe the sea-land breeze appeared in the low altitude which was below 200 m in the coastal zone. The stability change in the different height in the coastal zone was more stable than in the land zone,and the wind field change in the area was mainly in 300 m low altitude. At night,the temperature inversion often appears in the area,and the thickness of temperature inversion layer is stably during 200-300 m. The thermal internal boundary layer penetrated deeply into the land about 10 km,and the height could reach 800 m. The atmospheric diffusion ability in the coastal area was weaker and stronger in the land area.

POLLUTION TREND IN THE TUMEN RIVER AND ITS INFLUENCE ON REGIONAL DEVELOPMENT

The Tumen River had failed to meet Grade Ⅲ and Ⅳ levels in the environmental quality standard for surface water, and had exceeded Grade Ⅴ level. Surface water pollution is serious. The major excessive standard pollutants were COD Mn and SS. After taking effective treatment steps, the worsening trend of water pollution will be basically under control. But the change of runoff in the Tumen River is large in a year, especially during as long as five month freezing period, smaller flow and lower temperature of river waters led to weak dilution and self purification capacity. The water quality of the Tumen River will not reach the appoint functional water quality standards, even if sewage meets discharge standard, which will influence water resources utilization in the lower reaches of the Tumen River and regional economic development. Therefore water pollution has become the major restrictive factor of the development of the Tumen River area.

Numerical simulation of the transport and diffusion of dissolved pollutants in the Changjiang (Yangtze) River estuary

Based on a coupled hydrodynamic–ecological model for regional and shelf seas (COHERENS), a three-dimensional baroclinic model for the Changjiang (Yangtze) River estuary and the adjacent sea area was established using the sigma-coordinate in the vertical direction and spherical coordinate in the horizontal direction. In the study, changing-grid technology and the "dry-wet" method were designed to deal with the moving boundary. The minimum water depth limit condition was introduced for numerical simulation stability and to avoid producing negative depths in the shallow water areas. Using the Eulerian transport approaches included in COHERENS for the advection and dispersion of dissolved pollutants, numerical simulation of dissolved pollutant transport and diffusion in the Changjiang River estuary were carried out. The mass centre track of dissolved pollutants released from outlets in the south branch of the Changjiang River estuary water course has the characteristic of reverse current motion in the inner water course and clockwise motion offshore. In the transition area, water transport is a combination of the two types of motion. In a sewage-discharge numerical experiment, it is found that there are mainly two kinds of pollution distribution forms: one is a single nuclear structure and the other is a double nuclear (dinuclear) structure in the turbid zone of the Changjiang River estuary. The rate of expansion of the dissolved pollutant distribution decreased gradually. The results of the numerical experiment indicate that the maximum turbid zone of the Changjiang River estuary is also the zone enriched with pollutants. Backward pollutant flow occurs in the north branch of the estuary, which is similar to the backward salt water flow, and the backward flow of pollutants released upstream is more obvious.

Assessment of Water Quality of the Trans-Boundary Zarafshan River in the Territory of Uzbekistan

The Zarafshan river is a main trans-boundary river of the Aral Seabasin. As the main water resource, the Zarafshan river water is mainly used by the republics ofTajikistanandUzbekistan. We explored the trends of space-time pollution of river water with ammonium, nitrates, phosphates, biological oxygen demand (ВОD), fluorine and some heavy metals at seven water sampling points along theZarafshanRiver inUzbekistan. The experimental data showed that the water quality of the Zarafshanriver in 2002-2009 has undergone a considerable transformation, even by the length of the river. The chemical composition of the Zarafshan river water underwent changes due to the agricultural collector-drainage discharges and the sewage of the cities of Samarkand and Navoi. The water pollutants of the Zarafshan river, as a con- sequence of the agricultural pollution, consisted of mineralization, ammonium, nitrate, phosphate, and pesticides. Therefore, it is necessary to monitor the chemical composition of the large agricultural collector-drainage discharges into the river. The main sources of the heavy metals (primarily arsenic and zinc) in the Zarafshan river water were probably ore processing manufactures located interritoryofTajikistan.

平原河网地区典型旱地面源污染排放系数时间变化特征及影响因素研究

【目的】探明平原河网地区典型旱地离田排放系数的变化特征,为农业面源污染监测管理提供参考。【方法】以上海市崇明岛某典型旱地为研究对象,通过构建水文-水质协同监测系统,对旱地面源污染排放系数进行测算,明确排放系数的时间变化特征,分析排放系数的影响因素。【结果】日尺度下,氮、磷的离田排放系数变化范围分别为2.2~9843.9、0.08~667.0 g/(hm^(2)·d);月尺度下,氮、磷离田排放系数变化范围分别为0.02~17.2、0.001~1.04kg/(hm^(2)·m)。在降水产流事件中,氮离田排放系数与降水历时呈极显著正相关,磷离田排放系数与产流事件的总降水量、平均降水强度、最大小时降水强度极显著正相关。施肥后,氮日排放系数迅速增大,磷日排放系数无明显变化。各时间尺度下,氮排放系数与地表径流不存在显著相关性,磷排放系数与地表径流极显著正相关。【结论】氮、磷离田排放系数的日、月际变化幅度较大,氮离田排放系数易受施肥措施影响,磷离田排放系数则更易受降水和地表径流的影响。

伊洛河(巩义段)排污口表层水体微塑料的赋存特征、分布与风险评价

作为一种新污染物,微塑料可通过排污口进入河流。通过采集伊洛河(巩义段)13个入河排污口表层水体的样品,采用显微镜观察、激光红外等方法,对其赋存特征、分布进行分析及定性,并进行风险评价。结果表明:①伊洛河(巩义段)排污口表层水体中微塑料平均丰度为(96.5±35.5)n/L,检出形态纤维状和透明色占比较高,粒径以<0.5 mm为主。②检出塑料种类分别为聚酰胺(PA)、聚乙烯(PE)、聚丙烯(PP)、聚苯乙烯(PS)、聚对苯二甲酸乙二醇酯(PET)和聚氯乙烯(PVC),其中,PET占比为16%~50%,PE占比为22%~48%,每个样点二者占比之和均超过50%。③污染负荷指数法评估该研究区段为低风险,而微塑料聚合物组成危害指数法和潜在生态风险指数法表明,有PVC检出的样点排污口表层水体风险会升高。研究显示,伊洛河(巩义段)排污口水体中微塑料引起的环境风险不仅与其丰度有关,还依赖于微塑料的种类,微塑料的潜在风险应引起重视。

入河排污口水环境污染状况及综合治理方法研究

利用加权平均值和多个排放量计算方法对入河排污口水环境展开研究,采集各行政区的入河排污口的污水、化学需氧量、氨氮数据,得出结论:A行政区、B行政区、C行政区污染最重,污水排放量均已达到了3.2亿吨以上,E行政区、F行政区、D行政区的年污水排放量相对较少,均在0.5亿吨以上。选取近五年入河排污口污染物排放数据,结果表明,河底污染、河流内部水的流动力、入河排污口与污水管网设置不合理是造成入河排污口水环境污染的主要原因,并提出从污水管网建设、管理策略、监督体系等多个方面进行综合治理,改善水环境质量。

珠江源曲靖南盘江污染特征分析及对策措施

南盘江是珠江源头、云南曲靖人民的母亲河,其综合系统治理关系到曲靖的生态环境改善和经济社会的可持续发展。为精准掌握南盘江流域水污染问题,本研究详细分析了水质时空变化,降雨时城区管网溢流情况,沿岸排污口分布及污染物排放、合流制截污管网覆盖及漏损情况,南盘江干流闸坝运行调度情况。结果表明:南盘江流域水质劣Ⅴ类,重度污染,水质旱季劣于雨季,支流劣于干流,下游劣于上游,主要超标因子为NH 3-N和TP;当城区降雨量高于约10 mm时,部分支流白石江等雨水口大量生活污水溢流,雨污合流制难以应对降雨天气;干支流共有排口225个,抽检50个排口水质达标率约24%,超标排放情况普遍;曲靖城区城市建设落后,建成区约30 km 2采用雨污合流制,仍有约40%区域未覆盖截污管网;城区人均水资源量760 m 3,仅为云南人均的15.6%,全国的36%,沿岸闸坝蓄水满足农业灌溉用水需求,闸坝运行调度混乱,河道生态流量无法保障。建议以河长制为抓手,加强工业及城镇生活点源污染治理,优化区域水资源配置,推进河道综合治理、理顺管理机制体制,构建快处高效的治理执行体系,形成全社会参与的南盘江治理局面,方能促进南盘江水生态环境质量持续改善,惠及民生,还河于民。

入河排污口排查及其在桂林市水环境治理中的应用

入河排污口排查相关工作的开展和实施是水环境治理的重要环节,各地区都在积极响应国家号召,推进这方面工作的落实,并在入河排污口排查、监测和溯源等方面取得了一定成效。相关人员掌握了排污口数量和分布的基本情况,技术规范也更加完善,为排污口整治和水环境综合治理提供了参考和依据。但在相关工作的落实过程中也发现了很多问题,如入河排污口量大面广、区域分布差异大、混接混排、排放方式各异等一系列问题,在一定程度上增加了排查和综合治理的难度。在排查和监管工作中也存在主体责任不明、工作落实不细致等问题,需要进一步改进和完善[1]。本文简要分析了入河排污口排查工作的目标要求和技术要点、现状及存在的问题,并就相关工作的开展提出了一些建议和对策。

常州次级河流污染分析及治理方式探讨—以藻港河区段河道为例

本文研究了藻港河(三井段)主河道及民营河、大沟河、太湖河、大湾河、三井河、泰山河、五奎河等7条支流的水质情况。检测结果表明:藻港河(三井段)13个采样断面中,11个断面的水质指标符合GB 3838-2002[1]Ⅲ类标准,1个符合Ⅴ类标准,1个属于劣Ⅴ类标准;藻港河(三井段)支流共设16个采样断面,1个断面的水质指标符合GB 3838-2002Ⅳ类标准,2个符合Ⅴ类标准,13个属于劣Ⅴ类标准。主河道水质由支流河道水质决定。根据藻港河(三井段)主河道及支流的水质状况,本文从河道建设情况、工业源、生活源、地面径流污染等方面进行水质污染分析,从企业雨污分流、泵站截污、改建生态河道、排放口编码、河道长效管理等方面提出了治理措施,以期为城市次级河流污染分析及治理方式研究提供参考。

内蒙古入河排污口现状及整治建议

入河排污口排查整治是推动流域水生态环境质量提高的基础性举措。入河排污口规范化建设是“十四五”水生态环境保护的重要工作,对提高区域生态环境及促进绿色、高质量发展具有重要意义。通过分析内蒙古自治区入河排污口整治现状得出:按流域统计,黄河流域占41.8%;按类型统计,工业排污口占36.3%;按盟市统计,赤峰市占比个数最多,为35.2%。依据现状,提出按分类进行整治、建立健全长效机制等对策建议,为深入打好碧水保卫战、全面加快自治区入河排污口排查整治工作进度提供依据。

滇池流域汛期污染特征及分区管控策略研究

基于滇池流域长时间序列的降雨数据、河湖水质数据以及各类型排口水质数据,分析了滇池流域河湖水质变化对降雨的响应关系,提出了汛期污染分区控制的相关对策建议。结果表明:近年来滇池流域降雨集中程度增加,短时强降雨事件发生频率增大,汛期污染控制难度增大;河湖水质整体上呈现出汛期主要污染物浓度高于非汛期的现象,入湖河道氨氮和总磷与降雨量呈现出明显的正相关性;汛期污染主要来自于河道沿岸的合流制排口、种植业排口和分流制雨污混接口的排放;为提升汛期污染防治的精细化水平,建议按照城郊面山洪水冲击控制区、主城中心合流制污染控制区、二环外合流制溢流污染控制区、分流制排水系统混流及径流污染控制区、农业农村面源污染控制区来对滇池流域汛期污染进行分区控制。

水库水源的数据中心自然水冷却系统温排水影响分析

水库水源的低温水冷却系统是解决数据中心能耗问题的一种有效手段,但产生的温排水对环境的影响亦不容忽视。以武当云谷大数据中心为例,基于MIKE21 FM软件建立了丹江口水库坝下至黄家港水文站的平面二维数值模型,研究了数据中心温排水退水口设在不同位置对温排水扩散规律的影响。结果表明:随着温排水退水口位置处水深和流速的增大,温排水的最大温升和相应的温度混合区范围也逐渐减小,当水深超过2 m时,局部最大温升已低于1℃。研究成果可为采用水库低温水作为冷却水源的类似数据中心温排水退水口选址及温排水影响分析提供借鉴。

长江下游生态岛农村生活污水排放规律

为了明确长江下游地区农村生活污水排放规律,对长江入海口崇明生态岛A镇的农村地区展开了污水排放调研。结果表明:A镇户均常住人口为1.55人/户,人均用水量为79.5 L/(人·d),平均折污系数为0.76。农村生活污水中黑水排放量小、污染物浓度高,人均黑水水量占排水量的29.90%。农村生活污水时排水量、污染物浓度波动较大,7:00—8:00污染物浓度较高,在20:00排水水量达到全天的最大值。全年人均日排水量变化较大、日负荷变化较小,在国庆节、春节等节日人均排水量、负荷较大。研究结果对于长江下游生态岛农村生活污水治理的模式选择、装备研制、提标及资源化模式的探索具有重要意义。

淡水养殖排污口全过程监测体系分析

随着水产养殖业的快速发展,水产养殖污染防治监测体系的重要性日益显现,特别是水产养殖排污口已正式纳入入河排污口监测范围,因而对水产养殖污染治理和尾水排放提出了更为严格的监测要求。本文以Z省淡水养殖为主要研究对象,分析该区域淡水养殖总体概况和尾水主要排污特征,针对水产养殖排污口监测体系存在的基础薄弱、尾水监测体系待进一步完善以及排污口规范化待进一步实施等短板,从水产养殖排污口全过程监测的角度提出加强源头管控、尾水监测、排污口规范化和长效管理等建议,为水产养殖主体持续完善污染防治设施和管理提供参考,有效促进水产养殖产业绿色可持续发展。

污染源自动监测系统运行维护及管理研究

为了提升入河排污口自动监测系统的性能,便于对水环境质量进行监控和预警,对监测系统的性能展开研究。对自动监测站数据和手工监测数据进行比对分析,结果显示,技术误差满足规范要求,证明自动监测站的数据准确可信。根据实际项目经验,从运维机构的角度,针对排污口水质自动监测站的工作职责、季节性差异化运维、质量管理等方面存在的问题提出建议。

城市湖泊污染控制工程研究——以梅溪湖为例

在城市快速开发建设进程中,城市湖泊水环境面临着严峻考验。文章以梅溪湖为例,分析梅溪湖规划建设的成功经验,并针对晴天污水直排、初期雨水污染、管网病害等突出问题,采用排口智能化改造、管道病害修复、管网改造完善等工程措施,在控制入湖污染的同时兼顾景观功能。该工程的实施对完善城市排水体系、防治污染风险、改善湖泊水质具有重要意义,为城市湖泊污染控制提供有益借鉴。

Analyses of Physical and Chemical Parameters in Surface Waters nearby a Cement Factory in North Central, Nigeria

Water samples were collected from three stations along the water course of Oinyi River, Kogi State, Nigeria, bi-monthly for 12 months (October 2010 to September 2011). A total of 16 physical and chemical parameters (temperature, dissolved oxygen, biochemical oxygen demand, chemical oxygen demand, electrical conductivity, flow velocity, depth, nitrate, nitrite, phosphate, ammonia, pH, turbidity, total suspended solids, total dissolved solids and colour) were analyzed and results showed that pH (6.8 to 7.26), conductivity (106.0 to 211.7 μS/cm), colour (3.87 ± 0.159 Pt.Co), turbidity (14 - 22.7 NTU), total suspended solids (45 - 54 mg/l), biochemical oxygen demand (2.05 - 2.89 mg/l), chemical oxygen demand (17.19 ± 0.15 mg/l), temperature (24°C to 27°C) and depth (0.23 to 0.35 m) were significantly different across the different stations and between the months. However, total dissolved solids (52.7 to 108.8 mg/l), dissolved oxygen (6.02 to 7.01 mg/l), ammonia (0.00 to 0.02 mg·l-1), nitrite (0.01 - 0.09 mg·l-1), nitrate (0.045 ± 0.006 mg·l-1), phosphate (0.2 to 2.05 mg·l-1) and flow velocity (0.1 to 0.35 m·s-1) showed variations within the sampling stations. Maximum conductivity (211.7 μS/cm), colour (5.83 Pt.Co), turbidity (22.7 NTU), total suspended solids (54 mg/l), total dissolved solids (108.8 mg/l), nitrite (0.09 mg/l) and nitrate (0.006 mg/l) values were recorded at station 2 which is the discharge point of industrial waste. River water did show significant pollutional increase at the effluent impacted site during the present study. Dissolved oxygen showed direct relation with temperature, biochemical oxygen demand and chemical oxygen demand. The non-stop and continuous discharges of cement waste water into the river lessened water quality with significant or corresponding effect on the biota of the studied area, thus paving way for clear assertion that the water quality deterioration was as a result of the impacts of the waste water from cement industry.

控制单元污染源排污许可总量限值优化研究——以永定河流域为例

排污许可证制度是目前普遍采用的水环境管理的重要制度之一,在水污染控制和水环境质量改善中发挥着重要作用。通过将基于水环境容量约束和基于流域排放标准的允许排放量进行对比,构建了控制单元排污许可总量限值管理模式和污染源排污许可总量限值优化方法。基于永定河流域典型控制单元的实证研究表明,在执行流域排放标准时,北京段典型控制单元可满足水环境质量改善需求,但张家口段典型控制单元仍需要削减CODCr210.388 t/a。张家口段典型控制单元内2家污水处理厂上游间接排放固定源需分别削减CODCr0.002和32.039 t/a。

基于固定式ADCP的陈东港污染物通量计算

根据太湖流域西部重要入太湖河道陈东港2021年ADCP流量测验数据和水质在线监测数据,分析了该河道流量、污染物质量浓度和通量的年内变化特征,比较了流量、水质数据采集频次对污染物通量计算结果的影响。结果表明:2021年陈东港年平均流量为73.66 m^(3)/s,年径流量为23.29亿m^(3),日均流量年内波动剧烈,峰值出现在7月,其变化过程受降水影响显著;COD_(Mn)和TP质量浓度的年内波动也较明显,全年累计通量分别为10357 t和352 t。基于固定式ADCP流量测验数据计算污染物通量较基于水文巡测数据的精度提升约39.5%,两者差异主要集中在6—8月。若要将两种污染物年累计通量的计算相对误差控制在5%以内,流量采集频次不宜低于2 d一次;若相对误差控制在10%以内,流量采集频次不宜低于10 d一次,在丰水期(6—9月)和枯水期(12—2月)需提升至2 d一次。与流量采集频次相比,两种污染物年累计通量对水质采集频次变化的敏感性相对较低,当水质采集频次从8 h一次减少到30 d一次时,相对误差仍在5%以内。