小浪底水库对氨氮的水环境效应

采用1992年7月—2008年2月黄河干流潼关、三门峡、小浪底等水质监测断面氨氮逐月浓度监测数据,分析了小浪底水库运行前后潼关、三门峡、小浪底的氨氮年通量、年平均浓度变化情况,并结合潼关自动站与花园口自动站氨氮监测数据以及断面过水流量历史记录,研究了小浪底水库对氨氮的水环境效应。结果表明:小浪底水库运行后,就氨氮指标而言,小浪底坝下断面水质达标率大幅提高;从氨氮浓度波峰出现时间来看,小浪底断面氨氮浓度变化比潼关、三门峡断面滞后,滞后时间为30～60 d;小浪底水库下泄流量越大,有效库容越小,水库对氨氮的稀释作用越小,氨氮波峰滞后时间越短。     

黄河干流水样三氮测定保存方法的探讨

<正> 一、前言三氮在水质监测中系指氨氮、亚硝酸盐氮、硝酸盐氮等氮化物的三种存在形态。一般地表水中氨氮、亚硝酸盐氮、硝酸盐氮含量不大,只有生活污水、工业废水中含量较高。当水体中氨氮、亚硝酸盐氮含量突然增高,说明水体正受到污染;当水体中氨氮、亚硝酸盐氮含量很低,主要是硝酸盐氮时,则说明水体基本得到自净。因此氨氮、亚硝酸盐氮、硝酸盐氮在水体中的含量是衡量水     

以水质目标管理为抓手保护首都生命之水

正密云水库是首都重要饮用水源地和生态屏障,始终把保水作为首要政治责任,通过上游保水、护林保水、库区保水、依法保水及政策保水,多措并举保障水质安全、水环境安全。一水质监测为保护好密云水库水资源、水生态环境,管理处对入库水体、库区水体及出库水体建立了水质控制断面,定期进行监测。2002年起针对密云水     

立面二维水质模型预测小浪底出库水质研究

针对小浪底水库下半段库区出现水质水温分层现象,建立基于标准k-ε紊流双方程的立面二维水质模型对小浪底出库水质进行了预测。通过示踪试验确定水质模型的参数,并将氨氮含量作为预测水质参数,采用实测数据对模型进行了验证,结果表明:小浪底坝下段氨氮含量预测值与实测值相比较平均相对误差为12%,坝前断面垂向氨氮含量预测值与实测值相比平均相对误差为17%,表明该水质模型可以较准确预测小浪底出库水质。应用该模型预测2013—2014年度黄河调水期小浪底出库水质表明:2014年3月10日小浪底出库水氨氮含量将达到1.20 mg/L(超标),应从3月1日开始加大陆浑水库、故县水库闸门开启度,进行稀释调度,以确保调水水质不超标。     

太湖水质指标相关关系的研究

引入多元统计中的类离差平方和系统聚类法,对太湖焦山站的高锰酸盐指数、5 d生化需氧量、溶解氧、氨氮、亚硝酸盐氮、硝酸盐氮、总磷、总氮等8个水质指标进行了聚类分析计算,探索其相关关系.结果表明,硝酸盐氮与总氮、氨氮与亚硝酸盐氮、高锰酸盐指数与总磷可以聚为一类,而5 d生化需氧量与溶解氧各成为一类.研究结果为进一步改善太湖水环境提供科学依据.     

东风水库COD氨氮衰减系数分析

利用2006-2009年38次东风水库入库、出库水质、水量数据,采用常规监测资料估算法,分析率定COD、氨氮衰减系数,破解了通过水质模型计算纳污能力的核心难题,为实现最严格的水资源管理制度,明确水功能区限制纳污红线,产格控制入河排污总量提供技术支撑.     

石河水库水质氮的存在形式的研究

文章根据2013年1月～2017年7月石河水库蟠桃峪监测点水质采样监测结果,选取了硝酸盐氮、亚硝酸盐氮、氨氮、溶解氧、PH值和总磷等指标进行研究,对各类无机氮污染物的变化趋势及其与水质因子之间的相关性进行了分析,并通过多元回归分析,分别得出了硝酸盐氮、亚硝酸盐氮和氨氮的多元回归方程。     

浅谈我省水质监测站网规划

一、现状情况。江苏省水环境监测中心1996年通过国家质量技术监督检验检疫总局的网点考核，为国家级计量认证合格单位，2001年又通过了五年一次的复查换证考核。全省现有地表水水质监测站264个，地下水水质监测井186个，目前正常监测项目为水温、电导率、PH、溶解氧、氨氮、硝酸盐氮、亚硝酸盐氮、高锰酸盐指数、五日生化     

屋面储存雨水水质随时间变化的研究

研究屋面储存雨水在不同时间段内的水质情况,可为储存雨水的使用提供指导。以西安地区的降水为研究对象,采集雨水储存,并监测水质的变化。监测项目包括：水温、pH值、电导率、SS、COD、浊度、氨氮。监测分析结果表明：在监测时间段内储存雨水的硝酸盐氮呈上升趋势,浊度、SS、COD、氨氮随时间呈下降趋势。参考国家生活杂用水水质标准及地表水环境质量指标对不同监测时间段内的雨水水质评价,雨水储存30~40 d内基本为Ⅳ类水,此阶段为储存雨水的最佳利用时间,40 d以后储存雨水需要更新。     

江西千烟洲农业生态系统水环境氮污染研究

本实验以氨氮(NH4+-N)、亚硝酸盐氮(NO--N)、硝酸盐氮(NO3--N)及总氮(TN)为研究目标,选取松塘水库、G井、Ⅰ井、人工鱼塘、甘家水井、架竹河为研究点.近期(2010年1月-2010年5月)水质动态监测资料表明,千烟洲农业生态系统水环境氮污染以硝酸盐氮(NO3--N)为主,地下水流场上下游差异性较大;地下水流场下游甘家水井,硝酸盐最高含量达22.56 mg/L,最低含量14.80 mg/L,超过世界卫生组织(WHO)规定的生活饮用水标准10 mg/L,检出率100％,出现了硝酸根型地下水;农忙时人工鱼塘、架竹河水中亚硝酸盐氮(NO2--N)含量明显升高,高达约0.20 mg/L,对水中生物的生长极为不利;河、库、井水中氨氮(NH4+-N))浓度差异不显著,但随时间变化差异明显.通过研究“三氮”在地下水中的转化规律,为农业生产和地下污染防治提供依据.     

袁河底泥污染物监测与分析

本文通过对袁河沉积物中氨氮、总氮、总磷和COD(重铬酸钾法)含量的监测,分析袁河底泥污染物的分布规律,并通过同一断面袁河污染物与底泥中相应污染物含量的对比,研究底泥污染物的来源,由此得出除个别断面外,沉积物中污染物含量高的断面河水中的含量相应的也较高。对比袁河与太子河流域可知,袁河流域沉积物污染程度远低于太子河流域。这就为维持袁河河流生态健康,合理利用袁河水资源提供了依据。     

关于测定水中亚硝酸盐氮、硝酸盐氮、总氮的方法探讨

含氮化合物是水体污染监测中的重要指标,因此需要可靠精确的检测方法作为支撑。本文采用气相分子吸收光谱法对亚硝酸盐氮、硝酸盐氮、总氮进行检测分析,结果表明:标准曲线相关系数均大于0.999,检出限、精密度、准确度、加标回收率均满足方法要求。表明气相分子吸收光谱法具有较高的灵敏度和准确度,稳定性好,可实现样品在线自动稀释和在线消解,简化样品前处理过程,更适用于大批量含氮化合物水质检测工作。     

The Role of Sediments in the Nitrogen Budget of Lower Green Bay,Lake Michigan

The extreme southern portion of Green Bay is a shallow (1 to 5 m depth), eutrophic water body which receives considerable nutrients from the Fox River and metropolitan Green Bay, Wisconsin. Research to evaluate the effect of sediments on nitrogen (N) in the bay entailed periodic sampling of waters and sediments at six sites over 20 months and laboratory investigations of the rates of nitrification, denitrification, mineralization, immobilization, and N₂ fixation. The monitoring data indicated that the N concentrations, approximately 0.6 and 0.8 mg/L of inorganic and organic N, respectively, in the bay waters are considerably higher than the threshold limits that may cause algal bloom and aquatic weed problems. Consideration of the available sediment N pool with respect to recognizable N inputs indicated that only 1.2 percent of the yearly N loading from the Fox River is present in the active sediment layer. Nitrification and subsequent denitrification at the sediment-water interface as a result of intermittent wind stirring could be a major sink for N, but presently it has a minor impact due to the high loading rate of N in this ecosystem. The study indicates that even if approximately 50 percent of the present point source loading of N were eliminated by pollution abatement, the N input from nonpoint sources (combined with existing concentrations of phosphorus in the bay waters) would be sufficient to maintain eutrophic conditions.     

Nitrogen dynamics in sediment during water level manipulation on the Upper Mississippi River

Nitrogen (N) has been linked to increasing eutrophication in the Gulf of Mexico and as a result there is increased interest in managing and improving water quality in the Mississippi River system. Water level reductions, or ‘drawdowns’, are being used more frequently in large river impoundments to improve vegetation growth and sediment compaction. We selected two areas of the Upper Mississippi River system (Navigation Pool 8 and Swan Lake) to examine the effects of water level drawdown on N dynamics. Navigation Pool 8 experienced summer drawdowns in 2001 and 2002. Certain areas of Swan Lake have been drawn down annually since the early 1970s where as other areas have remained inundated. In the 2002 Pool 8 study we determined the effects of sediment drying and rewetting resulting from water level drawdown on (1) patterns of sediment nitrification and denitrification and (2) concentrations of sediment and surface water total N (TN), nitrate, and ammonium (NH). In 2001, we only examined sediment NH and TN. In the Swan Lake study, we determined the long‐term effects of water level drawdowns on concentrations of sediment NH and TN in sediments that dried annually and those that remained inundated. Sediment NH decreased significantly in the Pool 8 studies during periods of desiccation, although there were no consistent trends in nitrification and denitrification or a reduction in total sediment N. Ammonium in sediments that have dried annually in Swan Lake appeared lower but was not significantly different from sediments that remain wet. The reduction in sediment NH in parts of Pool 8 was likely a result of increased plant growth and N assimilation, which is then redeposited back to the sediment surface upon plant senescence. Similarly, the Swan Lake study suggested that drawdowns do not result in long term reduction in sediment N. Water level drawdowns may actually reduce water retention time and river‐floodplain connectivity, while promoting significant accumulation of organic N. These results indicate that water level drawdowns are probably not an effective means of removing N from the Upper Mississippi River system. Copyright © 2006 John Wiley & Sons, Ltd.     

Periphyton contribution to nitrogen dynamics in the discharge from a wastewater treatment plant

To evaluate the importance of periphyton to nitrogen dynamics in the discharge from wastewater treatment plants (WWTPs), we examined changes in total and inorganic nitrogen content downstream from a WWTP on the Kurose River in Hiroshima Prefecture, Japan. At 0.7 km downstream of the WWTP (point A), NH₄⁺?N was the dominant form of inorganic nitrogen, but concentrations decreased rapidly to 5 km downstream (point B). In contrast, no significant change in the [NO₂^?+ + NO₃^?]?N concentration was observed between the two points. Total nitrogen (TN) load decreased significantly between the two points, suggesting that sorption and/or denitrification occurred in the river channel. Potential rates of nitrogen sorption and transformation by periphyton were determined in a loboratory experiment in which changes in the nitrogen content of river water were examined in an acrylic chamber with periphyton. Nitrification and nitrogen removal occurred mainly in the periphyton. The contributions of periphyton activity to TN and NH₄⁺?N decrease in the field, as estimated from the results of the laboratory experiments, were 6–18% and 23–72%, respectively. These results suggest that periphyton plays an important role in decreasing NH₄⁺?N concentration in the discharge from wastewater treatment plants.     

排水农田氮素运移,转化及流失规律的研究

在总结文献和室内外试验基础上，对排水条件下氮素运移，转化及流失规律进行了分析研究；建立了一维、二维土壤水和地下水中氮素运移转化数学模型；探索了有限元数值计算法耦合求解水流和氮素运移模型，并提出了改进流线追踪法，克服已有简易计算方法中采用经验数据，精确方法计算繁复，且耗机时多的缺点，可用于排水农田氮素运移长期预报。     

灌溉施肥条件下田间氮素在土壤中迁移情况的研究

结合唐山市农业地区灌溉施肥的实际情况 ,通过野外田间在灌溉降雨及施肥的实际条件下 ,对土壤剖面上水分及三氮含量等的长期监测和分析 ,结合室内的土柱模拟试验以及建立数学模型模拟计算等工作 ,对不同条件下的土壤水分及土壤中氮素的变化进行了研究     

天然水体氮自净过程及硝化所需溶解氧源试验验证

通过试验验证了天然水体中确实存在氮的自然净化过程和同步硝化/反硝化途径。在氮与有机物浓度较低时,遮光阻断藻类光合作用试验表明,大气复氧足以使试验水质条件下的氮和有机物完全氧化。然而,有机物过早消耗对硝化后产生的硝酸氮再行反硝化作用不利。反硝化反应彻底进行可以通过外加碳源方式实现。COD初始浓度较高会引起异养菌对氧的大量消耗,使本来数量就处于劣势的硝化细菌的硝化反应受阻。     

曝气炭砂滤池去除氨氮的生产性示范工程研究

通过运行炭层空气曝气活性炭-石英砂双层滤池(简称曝气炭砂滤池)生产性示范工程,并与无曝气炭砂滤池及砂滤池进行对比,研究了曝气炭砂滤池作为快滤池时对水中氨氮及亚硝酸盐氮的去除性能。结果表明,曝气炭砂滤池可将氨氮浓度低于2.5mg/L的进水处理至0.5mg/L以下,且进水氨氮低于1.5mg/L时不需曝气,其去除效果显著优于普通炭砂滤池和石英砂滤池;曝气炭砂滤池亦可有效去除亚硝酸盐氮。用曝气炭砂滤池替代石英砂滤池是水厂提升氨氮去除能力的一种可行的滤池改造方式。     

生物有机肥与水分联合调控下稻田土壤氮素变化规律

为了探究生物有机肥和控制灌溉联合调控下稻田土壤氮素变化的特征和规律,开展了水稻小区种植试验。试验设置2种灌溉模式（常规淹灌（F）、控制灌溉（C））和3种施肥模式（全施化肥（A）、生物有机肥等氮替代15%化学氮肥（B）、生物有机肥等氮替代30%化学氮肥（C））,分析水稻生育期内土壤铵态氮与硝态氮含量的变化特征。试验表明：至水稻分蘖期时,相同灌溉模式下,配施生物有机肥处理的稻田土壤铵态氮含量均值均低于全施化肥处理,降幅为19.85%~48.78%,土壤硝态氮含量均值是生物有机肥等氮替代30%化学氮肥的处理低于全施化肥处理,降幅为15.35%~33.08%;而从水稻拔节期起,相同灌溉模式下配施生物有机肥处理的稻田土壤铵态氮平均含量比全施化肥处理增加了12.71%~56.26%,除FB处理硝态氮含量降低外其余配施生物有机肥处理的土壤硝态氮平均含量比全施化肥处理增加了19.21%~105.80%。控制灌溉的水稻全生育期土壤硝态氮含量显著高于常规淹灌（P＜0.05）,而土壤铵态氮含量则是常规淹灌高于控制灌溉。结果表明：生物有机肥配施化肥有利于水稻分蘖期后土壤铵态氮和硝态氮含量的积累,提升了稻田土壤氮素的养分累积,其中生物有机肥等氮替代15%化肥的效果较好。控制灌溉使得土壤硝态氮含量增加,同时也减少了土壤铵态氮的含量。综合考虑环境与经济效益,控制灌溉与生物有机肥等氮替代15%化肥的稻田水肥管理模式较好。