南广河水体中砷铅铬含量分布特征及质量探讨

本文对南广河水体中的砷镉铅铬含量分布特征进行了描述,并探讨了南广河的水质质量。结果表明：南广河从上游到了游水体中污染物含量为增大趋势;在时间上也存在一定的变化,枯水期水体中污染物含量高于水期和丰水期。目前南广河综合水质质量可满足Ⅱ类标准要求。     

青竹江水环境耗氧污染物含量分布特征及质量评价

本文对青竹江水环境中耗氧污染物(CODCr、BOD5和NH3-N)含量分布特征进行了探讨,并对青竹江的水质质量进行评价。结果表明,青竹江从上游到下游水体中污染物含量为增加趋势,在时间上也存在一定的变化,枯水期水体中污染物含量高于平水期和丰水期,目前青竹江综合水质可满足Ⅱ类水质标准要求。     

江安河水质特征分析及治理对策研究

采用综合评价与分类评价相结合的方法,分析江安河水质特征,旨在发现影响河流水质的主要污染物和污染源,为江安河水污染防治争水责源利用提供科学依据.2011年10月对江安河全段水质进行了统一标准监测,监潮项目有氨氮、总磷、COD、浊度,共4个项目;2012年4月再一次对江安河全段进行监测,并增加测量其水体中几种重金属含量.总体上,上游和中游断面均属清洁水质,下游断面属污染水质.河流综合污染指数、营养盐类污染指数、重金属污染指数均沿流程顺序增高.主要污染物为化学需氧量、氮磷类污染物.上游多为农业灌溉区,中下游污染较为严重,其中生活源、工业源排放的污水是影响江安河水质的主要污染源.     

基于MIKE21的城市入河排污口水质影响预测研究——以南方某城市污水处理厂为例

排污口的设置往往会导致附近水域出现水质超标现象,尤其对于城市内河道,涉及群众用水健康及对周边敏感区域的影响,需要对排污口排放污染物的影响情况进行研究。以南方某城市污水处理厂排污口为例,采用MIKE21二维水质模型模拟了6种工况下COD、NH₃-N两种入河污染物对下游水体的影响情况。结果表明,正常排放时COD、NH₃-N对下游水体影响较小,水质基本满足排污口所在河段水功能区水质要求,事故排放时,对下游造成10km以上的影响。模拟结果基本可以反映排污口排放污水对河道下游水质的影响情况,可为入河排污口排放污染物影响预测提供参考依据。     

实验室率定法测算长江南通段污染物降解系数

污染物降解系数是确定水环境容量的关键参数之一,本文采用实验室率定法,采集长江南通段的水样,分别于6℃、10℃、16℃、20℃室温下,在实验室内进行周期为20天的室内水质分析,根据室内水质分析结果,测算出不同温度下长江南通段"十二五"减排的约束性指标化学需氧量、氨氮的降解系数,并定性分析了长江水体中污染物本底浓度、可生化性、pH值等环境因子对污染物降解系数可能发生的影响。     

北京市南沙河流域水环境质量评价研究

利用2011~2016年的监测数据,对北京市海淀区南沙河流域的水环境质量进行了评价分析,结果表明:该流域水质一直为劣Ⅴ类,其中2011~2014年氨氮浓度呈逐年上升趋势,其他耗氧有机物、总磷主要污染物指标在2014年达到峰值,到2015年略有好转,但5年年均值均未达到水质类别要求;针对原因提出了能使南沙河水质得到持续有效改善的建议。     

察汗乌苏河水体中铅本底偏高探讨

本文在对不同时段察汗乌苏河水质监测结果的分析中,确认该河流存在水质中Pb含量偏高问题。通过对该流域自然影响因素的分析,提出了Pb含量偏高主要受自然因素影响,但流域内矿产资源的开发、污染物排放加重了影响程度。为保证察汗乌苏河水质按功能达标,提出了对察汗乌苏河流域都兰段Pb含量偏高现象进行进一步调查,并加强县城饮用水源地水质监测的建议。     

油菜秸秆腐解对自然水体的影响研究

为探究农田废弃物弃置水体对水环境质量的影响,对油菜秸秆在水中的腐解过程进行了实验研究。通过测量pH、DO、COD、氨氮、硝氮、总磷等水质指标来动态监测水质的变化。结果表明:DO含量初始为2mg/L,水体迅速转换为厌氧状态并保持稳定,35d后水体DO恢复至2~3 mg/L;水体中的COD含量在第3d达到最大值25mg/L,然后迅速下降,此后保持在15 mg/L左右;NH+4-N则在实验过程中缓慢增加,并在35d后维持在较高水平即10mg/L,而NO_3~--N、NO_2~--N含量较低,NO_3~--N含量为0.13mg/L,NO_2~--N含量为0.02 mg/L,TP含量则呈逐渐增加的趋势。油菜秸秆腐解的过程是厌氧腐解过程,此过程中各指标发生关联性的变化。随着时间的增长,水体由黑臭逐渐变清澈,说明水体具有一定的自净能力。     

皖苏两省首次进行长江流域跨界水质联合监测

正为贯彻落实《水污染防治行动计划》和《生态环境监测网络建设方案》,进一步加强跨界水体水质监测工作,提高水质监测数据质量,保证跨界水体水质监测数据的科学性和准确性,更好地适应环境保护管理和日后长江经济带发展要求。依据环保部《跨界(省界、市界)水体水质联合监测实施方案》,2016年6月12日,安徽省环保厅制定了《安徽省跨界(省界、市界)水体水质联合监测实施方案》(以下简称《实施方案》)。     

济宁南四湖水质富营养化评价及防治对策研究

以2012年南四湖水质监测数据为依据,采用修正的卡森指数法（TSIM）对南四湖水质进行评价。结果表明,修正卡森指数的评价结果为TSIM=56．04,南四湖已达到富营养化的标准。根据评价结果,从工业废水、生活污水排放、底质、农业生产、渔业养殖的影响方面分析了水体富营养化的原因,从减少外源污染物、应用生物措施和发展健康水产养殖模式三个方面提出了南四湖水体富营养化的防治对策。     

RIO GRANDE VALLEY,COLORADO, NEW MEXICO,AND TEXAS1

ABSTRACT: The Rio Grande Valley National Water-Quality Assessment study unit encompasses about 45,700 square miles in Colorado, New Mexico, and Texas upstream from the gaging station Rio Grande at El Paso, Texas, and includes surface-water closed basins east of the Continental Divide in New Mexico, and the San Luis Closed Basin in Colorado. The mean annual precipitation ranges from less than 6 to more than 50 inches; potential evapo-transpiration ranges from less than 35 to more than 80 inches per year. Land use is mainly rangeland, forest land, and cropland. Total irrigated acreage in 1990 was about 914,000 acres and water use was about 3,410,000 acre-feet. Two structural settings are found in the study unit: alluvial basins and bedrock basins. The alluvial basins can have through-flowing surface water or be closed basins. The discussion of streamflow and water quality for the surface-water system is based on four river reaches for the 750 miles of the main stem. The quality of the ground water is affected by both natural process and human activities and by nonpoint and point sources. Nonpoint sources for surface water include agriculture, hydromodification, and mining operations; point sources are mainly discharge from wastewater treatment plants. Nonpoint sources for ground water include agriculture and septic tanks and cesspools; point sources include leaking underground storage tanks, unlined or manure-lined holding ponds used for disposal of dairy wastes, landfills, and mining operations.     

福州城市排污规划布局的水环境影响研究

以闽江下游福州城区段为研究区间,分析了闽江下游福州段的水环境质量现状,采用二维水动力-水质耦合模型研究了枯水期城市排污口布局和排污强度规划对水环境质量的影响。研究结果表明,感潮河段排污存在明显的污染物上溯现象,在东南区水厂至马尾水厂备用水源地之间形成高浓度污染团,洋里和连坂排污口对东南区水厂水源地水质影响最为显著,高潮时刻的高锰酸盐指数增量将达1.0mg/L,氨氮增量将达约0.15mg/L,叠加本底值后水质已接近Ⅲ类标准限值。建议逐步将取水口向城市上游淮安段转移,更换取消东南区水厂的取水口。     

Influences of Water and Sediment Quality and Hydrologic Processes on Mussels in the Clinch River

Segments of the Clinch River in Virginia have experienced declining freshwater mussel populations during the past 40 years, while other segments of the river continue to support some of the richest mussel communities in the country. The close proximity of these contrasting reaches provides a study area where differences in climate, hydrology, and historic mussel distribution are minimal. The USGS conducted a study between 2009 and 2011 to evaluate possible causes of the mussel declines. Evaluation of mussel habitat showed no differences in physical habitat quality, leaving water and sediment quality as possible causes for declines. Three years of continuous water‐quality data showed higher turbidity and specific conductance in the reaches with low‐quality mussel assemblages compared to reaches with high‐quality mussel assemblages. Discrete water‐quality samples showed higher major ions and metals concentrations in the low‐quality reach. Base‐flow samples contained high major ion and metal concentrations coincident to low‐quality mussel populations. These results support a conceptual model of dilution and augmentation where increased concentrations of major ions and other dissolved constituents from mined tributaries result in reaches with declining mussel populations. Tributaries from unmined basins provide water with low concentrations of dissolved constituents, diluting reaches of the Clinch River where high‐quality mussel populations occur.     

Sources of water pollution and evolution of water quality in the Wuwei basin of Shiyang river, Northwest China

Based on surveys and chemical analyses, we performed a case study of the surface water and groundwater quality in the Wuwei basin, in order to understand the sources of water pollution and the evolution of water quality in Shiyang river. Concentrations of major chemical elements in the surface water were related to the distance downstream from the source of the river, with surface water in the upstream reaches of good quality, but the river from Wuwei city to the Hongya reservoir was seriously polluted, with a synthetic pollution index of 25. Groundwater quality was generally good in the piedmont with dominant bicarbonate and calcium ions, but salinity was high and nitrate pollution occurs in the northern part of the basin. Mineralization of the groundwater has changed rapidly during the past 20 years. There are 23 wastewater outlets that discharge a total of 22.4 x 10(6)m(3)y(-1) into the river from Wuwei city, which, combined with a reduction of inflow water, were found to be the major causes of water pollution. Development of fisheries in the Hongya reservoir since 2000 has also contributed to the pollution. The consumption of water must be decreased until it reaches the sustainable level permitted by the available resources in the whole basin, and discharge of wastes must also be drastically reduced.     

长山河水质评价及变化趋势分析

以2015 ～2019年长山河4个水质监测站的监测数据为基础,采用综合水质标识指数法对其历年水质进行评价,利用季节性kendall检验法对各监测断面的高锰酸盐指数,氨氮,总磷等3个监测指标变化趋势进行分析.结果 表明:长山河各断面的综合水质均达到或优于水功能区目标要求,水质污染总体呈下降趋势,其中长山河大桥和长山闸一号...     

基于灰色关联分析的岷江上游流域震后水质综合评价

汶川大地震是我国建国以来强度最大、破坏最严重的一次地震,使本就脆弱的岷江上游生态环境和水环境受到极大影响,岷江是成都市和都江堰市的主要水源,本次地震又发生在这两大城市的上游,震区中岷江水质直接关系到这两个城市的用水安全。本文根据跟岷江映秀段的水质监测结果,利用灰色关联分析法对水质进行综合评价分析,研究震后岷江水质特征,为岷江的水环境保护及成都与都江堰的饮用水安全提供参考。     

塔里木河干流生态治理输水抢救工程

塔里木河流域的生态环境问题引起了国内外的普遍关注。为了维护下游日益劣变的生态环境，塔里木河流域管理局积极实施了塔里木河干流生态治理抢救工程，以增加向塔里木河下游的输水量，改善塔里木河流域下游绿色走廊的生态环境状况。自干流中游沙子河-乌斯满河-阿其克河口段河道整治工程竣工后，塔里木河干流向下游输水效率有了明显的提高。     

MUNICIPAL POINT SOURCE AND AGRICULTURAL NONPOINT SOURCE CONTRIBUTIONS TO COASTAL EUTROPHICATION1

ABSTRACT: Tidally influenced reaches of several coastal rivers in eastern North Carolina are suffering from very serious water quality problems — massive surface blooms of noxious blue-green algae, major fish kills from anoxic water, epidemics of red sore disease among fish, fresh water intrusion into estuarine waters, and declining commercial and sports fisheries. An intensive investigation of point source and nonpoint source inputs of nutrients was conducted in one of the eutrophic rivers, the Chowan River. Nonpoint source loading dominated the estimated annual flu of nutrients from the river basin. Automated water quality samplers were utilized to record nutrient levels in stormflow and baseflow from several small agricultural watershed in the basin. Levels of nitrate nitrogen and total phosphorus were from five to 40 times greater in these agricultural watersheds than levels in mostly forested watersheds. Existing water quality data in these eutrophic river basins implicate agricultural activities – particularly animal operations and cropland in watersheds with extensive drainage improvements – as the major contributing factor to the water quality problems.     

ENVIRONMENTAL IMPACT OF STREAM CHANNELIZATION1

ABSTRACT Geologic, engineering, and biological investigations of six Pennsylvania coldwater streams were undertaken to determine the impact of channel modifications instituted both prior to and following Hurricane Agnes. The primary focus of the study was on the ecological changes brought about by stream channelization. No long-term deleterious effects on water quality, attached algae, benthic fauna, or forage fish populations were found. Trout, however, were found to be greater in numbers and weight in natural than in channelized stream reaches. Lack of suitable physical habitat appears to be the primary cause of reduced trout populations in stream reaches which have been channelized.     

Riparian Bird Communities as Indicators of Human Impacts Along Mediterranean Streams

Riparian areas link aquatic and terrestrial habitats, supporting species-rich bird communities, which integrate both terrestrial and aquatic processes. For this reason, inclusion of riparian birds in stream bioassessment could add to the information currently provided by existing programs that monitor aquatic organisms. To assess if bird community metrics could indicate stream conditions, we sampled breeding birds in the riparian zone of 37 reaches in 5 streams draining watersheds representing a gradient of agricultural intensity in central Italy. As a more direct indicator of water quality, stream macroinvertebrates were also sampled for computation of the Italian Extended Biotic Index (IBE). An anthropogenic index was calculated within 1 km of sampled reaches based on satellite-derived land-use classifications. Predictive models of macroinvertebrate integrity based on land-use and avian metrics were compared using an information-theoretic approach (AIC). We also determined if stream quality related to the detection of riverine species. Apparent bird species diversity and richness peaked at intermediate levels of land-use modification, but increased with IBE values. Water quality did not relate to the detection of riverine species as a guild, but two species, the dipper Cinclus cinclus and the grey wagtail Motacilla cinerea, were only observed in reaches with the highest IBE values. Small-bodied insectivorous birds and arboreal species were detected more often in reaches with better water quality and in less modified landscapes. In contrast, larger and granivorous species were more common in disturbed reaches. According to the information-theoretic approach, the best model for predicting water quality included the anthropogenic index, bird species diversity, and an index summarizing the trophic structure of the bird community. We conclude that, in combination with landscape-level information, the diversity and trophic structure of riparian bird communities could serve as a rapid indicator of stream-dwelling macroinvertebrates and, therefore, degradation of in-stream biotic integrity.