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1.
甲烷(CH4)和氧化亚氮(N2O)是大气中重要的温室气体,对全球变暖和大气化学有重要作用。受人为活动影响较大的河流、河口是大气中CH4和N2O的重要源。于2019年春季、2020年秋季台风前后沿三亚河从下游到上游采集了11个站位的样品,测定三亚河水体中CH4、N2O浓度及相关参数,并估算了水-气界面释放通量。结果表明:春季、秋季以及台风后CH4平均浓度分别为(15.92±23.04)、(364.43±265.41)、(666.02±502.60) nmol/L,N2O平均浓度分别为(24.37±19.88)、(8.47±5.19)、(47.48±33.47) nmol/L,台风后大于台风前。水体中CH4、N2O主要受溶解氧(DO)和降雨影响,下游河段主要受潮汐作用影响。现场产生和沉积物释放是水体中CH4的主要源,硝化作用是水体中N2  相似文献   

2.
宁夏典农河是黄河宁夏段的主要入黄排水沟之一,其水质状况对黄河宁夏-内蒙古段跨省流域水质安全至关重要。选取典农河2011—2020年10个监测点位的16项水质参数,采用综合污染指数(WPI)法,结合相关性分析、主成分分析、聚类分析等分析方法,综合分析该流域水污染特征,并对污染程度进行评估,对污染因子和污染原因进行解析,最终提出管控建议。研究结果表明:2011—2020年,影响典农河水质的主要污染因子为CODCr、NH3-N、TP、TN,对应的年均浓度范围分别为22.3~71.5、0.64~9.09、0.173~0.662、2.89~21.52 mg/L,超标率分别为46%、8%、13%、85%。典农河2011—2020年WPI范围为0.59~1.74,重金属含量一直维持在较低水平。流域TN与TP年均浓度比值范围为20~84,整体呈下降趋势,且各监测点的差异性逐渐减小;BOD5与CODCr浓度比值范围为0.02~0.19,反映出典农河流域水体可生化性较差。各监测断面污染物之间存在较强相关性,其中:流域C...  相似文献   

3.
以2016—2020年古泊善后河国家和省级地表水监测网水质例行监测数据为依据,采用水质指数法(WQI)对古泊善后河水质污染状况进行综合评价;基于水质评价结果,选取影响最大的两项指标CODMn和TP,于2020年10月对古泊善后河开展加密监测,调查分析污染来源。结果表明,2016—2020年古泊善后河水质波动变化较大,汛期降雨对水质下降影响明显,CODMn、TP、CODCr、氟化物和BOD5是影响古泊善后河水质的主要指标;加密监测期间,古泊善后河干流水质CODMn和TP指标浓度分别升高28.9%、38.3%,其中宿迁段升幅显著高于连云港段;支流水质超Ⅲ类比例为22.9%,劣Ⅴ比例为6.3%;部分乡镇生活污水直排和持续降雨将农田中高浓度污染物冲刷进河流支浜,是导致水质下降的主要原因。  相似文献   

4.
为建立一种针对城市河流水体常规污染指标的快速原位监测方法,首次运用紫外光诱导荧光分析仪对扬州市60条城市河流进行水体三维荧光光谱(EEM)测量,形成了具有多样性的水质样本集合。利用峰值拾取法、相关性分析和主成分分析3种方式从三维荧光光谱中提取溶解性有机物(DOM)污染信息,结合多元线性回归算法(MLR),建立与化学需氧量(CODCr)、高锰酸盐指数(IMn)、氨氮(NH3-N)和总磷(TP)4项常规水质污染指标相关的预测模型。研究结果表明,峰值拾取法结合相关性分析可以有效地反映水体EEM中的污染特征和状况,由此建立的4项水质指标预测模型训练集决定系数均>0.82,预测结果与国家及行业标准方法分析值之间具有较低的均方根误差,说明该预测方法具有较好的准确度和精密度,为城市广域水体的高效、原位监测提供了一种有效的解决方案。  相似文献   

5.
黑龙江流域地处世界三大黑土区之一的中国东北平原,土壤腐殖质含量高,这些腐殖质随着地面径流进入水体,成为流域溶解性有机物(DOM)的自然本底(环境背景)。自然本底的存在导致流域水质有机污染综合指标不能真实反映流域的人为污染,流域背景区内高锰酸盐指数、化学需氧量背景值范围分别为3.0~11.7、14.3~40.5 mg/L。流域部分水质考核断面水质受到有机质背景值的影响。由于叠加人为污染,定量分析高锰酸盐指数、化学需氧量背景值范围存在很大难度。重金属元素相对稳定,相对于"六五"时期重金属背景值,目前水体中重金属含量普遍升高。结合水环境管理需求,背景值研究成果应用于水环境管理还需要进一步深入研究和实践。笔者在综述黑龙江流域水环境背景值研究基础上,总结目前存在的问题,提出水环境背景值研究建议,为科学客观评价流域水质提供参考。  相似文献   

6.
结合紫外可见吸收光谱与三维荧光光谱法,利用平行因子分析方法研究哈尔滨市磨盘山水库水体中的溶解性有机质(DOM)。结果表明,水体DOM吸收系数α355平均值为(4.71±0.66)m-1,表明水库中有色溶解性有机质(CDOM)较高;水库水体DOM存在3个荧光组分,分别为类腐殖质C1(345 nm、440 nm)、类腐殖质C2(285 nm、405 nm)和类富里酸组分C3(275 nm、475 nm);C1、C3呈现显著的正相关性,自生源指数与C1呈显著的负相关性;类腐殖质的荧光强度在深层水体中逐渐增加,且深层水体的腐殖化程度较高,较为稳定;水库中心水体中DOM的自生源特征较其他区域明显,浮游植物和细菌的有机体降解产物增加。  相似文献   

7.
采用3种方法分析黑龙江省松花江流域高锰酸盐指数非点源污染的负荷。分析结果显示,非点源污染造成的松花江流域高锰酸盐指数负荷约为70%;松花江流域支流源头属于高高锰酸盐指数河段,本底值约为5mg/L,河流流经1000Km非点源污染会增加高锰酸盐指数约1mg/L;松花江流域河流中高锰酸盐指数含量高的主要原因是流域内土壤有机质含量高。  相似文献   

8.
对2006—2019年赣江水体及水库丰水期-枯水期的总氮(TN)、氨氮(NH3-N)、硝态氮(NO-3-N)和总磷(TP)浓度变化和分布特征进行分析。将赣江按河谷地形和河道特征划分为上游、中游、下游3段;根据水流来源将赣江划分为章水、桃江、湘水、贡水、泸江、赣江干流。结果显示:桃江TN质量浓度在2011年枯水期取得最大值8.26 mg/L;章水TP质量浓度在2007年枯水期取得最大值0.18 mg/L,整个赣江丰水期-枯水期的TP质量浓度在0.02~0.18 mg/L范围内浮动,变化幅度较小;章水NH3-N浓度在2008年枯水期取得最大值1.86 mg/L,而在2017—2019年NH3-N的浓度基本处于0.5 mg/L以内,达到《地表水环境质量标准》(GB 3838—2002)Ⅲ类水质标准。万安水库和峡江水库对总氮的滞留率,丰水期分别为24.26%、17.44%,枯水期分别为21.36%、16.60%;对总磷的滞留率,丰水期分别为24.78%、19.05%,枯水期分别为33....  相似文献   

9.
基于2013年凤羽河流域水质氮磷监测数据,解析流域水质氮磷特征,并分析影响其变化因素。结果表明:凤羽河水质氮磷质量浓度较高出现在3个时段,2月份,TN 0.95 mg/L~2.47 mg/L,以NO_3~--N(55.6%)和DON(32.0%)为主,人类活动是影响的主要因素;5—6月,TN 0.77 mg/L~2.47 mg/L,以NO_3~--N(64.3%)为主,TP 0.08 mg/L~0.70 mg/L,以PP(56.4%)和DTP(43.6%)为主,水稻种植和初期降雨是影响的主要因素;7—9月,TN 0.76 mg/L~3.73 mg/L,以NO_3~--N(47.4%)和PN(35.4%)为主,TP 0.07 mg/L~0.97 mg/L,以PP(74.6%)为主,日降雨量是影响的主要因素。治理凤羽河流域农业面源污染应分时段、分区域调控。  相似文献   

10.
选取2016—2022年攀枝花市环境空气质量监测数据,基于年度、季度、月度、小时时间尺度评价环境空气质量综合指数贡献率。结果表明,攀枝花市污染类型已由传统的单一工业型污染转变为复合型污染,且污染物在不同时间尺度下的分布特征明显。从季度尺度来看,第一季度细颗粒物(PM2.5)综合指数贡献率较大,第二和第三季度臭氧(O3)综合指数贡献率较大,第四季度二氧化氮(NO2)及PM2.5综合指数贡献率较大。从月度尺度来看,O3在3—8月的贡献较大,PM2.5、NO2、可吸入颗粒物(PM10)、一氧化碳(CO)、二氧化硫(SO2)在1—2月及11—12月的贡献较大。从小时尺度来看,O3在13—19点贡献较大,PM10、PM2.5、CO在8—13点贡献较大,SO2在9—13点贡献较大,NO2在8—1...  相似文献   

11.
Minho River, also called Miño (in Spain), extends to about 300 km from Spain to Portugal. The source of the river lies in Spain and in the last 75 km, the river defines the border between Portugal and Spain. Under the scope of a cooperation project between North Portugal and Galicia region of Spain, titled: “Valorization of the natural resources of the Minho/Miño drainage basin”, seven water-sampling campaigns were carried out during the last 2 years in Minho River basin. Seven sampling sites were selected along the international stretch, and five were chosen in the main Portuguese and Spanish tributaries of Minho River. Water quality based on the physicochemical and microbial parameters was assessed. According to the Portuguese legislation for surface waters, the international section of Minho River presents a reasonably good water quality (BOD5 <5 mg/L, TNK <2 mg/L, and total phosphorous <1 mg P/L). Valença and Louro were found to be the most polluted sampling sites and Louro the most polluted tributary (maximum values observed: TSS?=?26 mg/L, BOD5?=?6.6 mg O2/L, COD?=?20.8 mg O2/L, total nitrogen?=?9.9 mg N/L; minimum value observed: OD?=?1.3 mg O2/L). A one-dimensional stream water quality model QUAL2Kw was calibrated using data measured in field surveys along the international stretch of Minho River. QUAL2Kw was also used to predict the impact of flow conditions, discharges, and tributaries on the water quality of international stretch of Minho River, essential to establish proposals for management and planning of Minho River Basin.  相似文献   

12.
采用超滤法、紫外-可见吸收光谱和三维荧光光谱分析法研究了北京市西城区4个典型功能区(居民区、文教区、交通区、商业区)雨水管网表层沉积物中不同分子量溶解性有机质(DOM)的分布特征和光谱特性。结果表明:雨水管网沉积物DOM以小分子量组分为主,约占整体水平的60%~70%。通过分析还发现,沉积物中小分子量(小于3k Da)DOM主要是类蛋白物质,而腐殖类物质主要集中在DOM的大分子量(大于10k Da)区域,微生物活动对小分子量DOM贡献作用显著,由此可见,DOM的分子组成和结构特性在一定程度上可以作为雨水管网沉积物DOM主成分和来源的衡量指标。4个功能区DOM腐殖化水平较低,表现出随分子量增大DOM腐殖化程度升高的规律。  相似文献   

13.
A modified Streeter–Phelps equation and the Hydrological Engineering Centers River Analysis System (HEC-RAS) were combined to assess water quality of the Tan-Sui River and its tributaries. The Tan-Sui River is the main source of water supply for northern Taiwan, and the water quality of its stream is significantly affected by tides. In this study, HEC-RAS was employed to assess the impact of tides on water quality and to calculate reoxygenation coefficients. The modified Streeter–Phelps equation was used to calculate water quality in terms of contaminant degradation and reoxygenation. Biochemical oxygen demand (BOD) and ammonia nitrogen (NH3–N), the most important identified sources of water pollution in the rivers investigated, were evaluated. Dissolved oxygen (DO) was also simulated, since it is often used as a staple of water quality. Results showed that employing HEC-RAS for hydraulic calculations improves the modified Streeter–Phelps simulation. In river sections without tidal influence, water quality was sensitive to the BOD and NH3–N degradation constants. Downstream of Chin-Mei Creek, while the BOD degradation constant decreased by 80%, BOD and DO concentrations increased from 7.1?mg/L to 10.7?mg/L and 5.0?mg/L to 7.2?mg/L, respectively, indicating that water quality was not as sensitive to variations of the BOD degradation constant as expected. The concentrations of DO and BOD at the river mouth had a significant impact on water quality for the tidal sections of the investigated rivers due to mixing of tidal and river waters. The BOD and NH3–N degradation constants in the tidal sections had little impact on water quality simulations. This study demonstrated the innovative combination of the modified Streeter–Phelps equation and HEC-RAS to assess the impact of tidal variation and to simulate the water quality of a tidal river when available data is rather limited.  相似文献   

14.
The study dealt with the method to predict the BOD5 in effluent from industrial wastewater by using the UV absorption from two wavelengths, 260 and 550 nm. The interference from suspended solids was reduced. In the same time, COD was used as the secure value to calculate BOD5. From the representative wastewater treatment plants, the estimated effluent BOD5 of wastewater from the Para rubber industry showed an average error at ±2.97 mg/l. While it was at ±3.31 mg/l, for frozen seafood industry. The simple mathematic equations in this study gave the assuring method for BOD5 estimation without time consuming.  相似文献   

15.
Contamination of oxygen-consuming organics (OCOs) was one of the most serious problems in the Yellow River of China. This study was conducted to analyze monitoring of the data on OCOs contamination for the river in 1980 and during 1992–1999 as well as examining the effect of suspended solids (SS) on chemical oxygen demand (CODMn) and biochemical oxygen demand (BOD5) of river water. Several significant results have arisen from the study. First, CODMn and BOD5 of the river water showed an increasing trend from the upper to the lower reaches of the mainstream. BOD5 values of river water in 1992 were significantly higher than those in 1980 and showed an increasing trend during 1992–1999. Second, OCOs in river water of the mainstream was attributed mainly to point sources; the ratio of point to non-point sources of BOD5 was about 2.81. The load from point sources showed an increasing trend during 1992–1998. In contrast, the load from non-point sources manifested a decreasing trend during this period; this was caused by the decreasing trend of SS content in river water. The total load of BOD5 from point and non-point sources displayed an increasing trend during 1992–1998. Third, as the humic substances in SS can hardly be biologically oxidized in natural conditions but can be oxidized by chemical oxidants such as potassium permanganate, CODMn was not suitable for being regarded as a parameter reflecting the pollution degree of OCOs in river water with a high SS content.  相似文献   

16.
The aim of this study was to evaluate the water quality of the Cértima River basin (Central Portugal). For that purpose, surface water samples were collected in March, May and July 2003, at 10 selected sampling sites, and were analysed for physicochemical parameters, namely temperature, conductivity, pH, total suspended solids, dissolved oxygen, biochemical oxygen demand (BOD5), Kjeldahl nitrogen and total phosphorus. Results revealed an acceptable water quality during the spring season. Maxima of 64 mg dm−3 for BOD5, 39 mg dm−3 for Kjeldahl nitrogen, and 5.2 mg dm−3 for total phosphorus, were recorded during summer, indicating a significant degradation of the water quality in a river stretch located downstream of the town of Mealhada. These values, which did not comply with the objectives of minimum quality for surface waters prescribed by the Portuguese legislation, were related to domestic wastewater discharges and runoff waters from a cattle farm. Besides their effects on the middle stretch of the river, these pollution sources were the most likely cause of the high nutrient load in downstream waters, and thus may have a major impact on the trophic status of Pateira de Fermentelos, a sensitive wetland area located in the lower Cértima basin.  相似文献   

17.
2001-2015年松花江流域水污染变化特征研究   总被引:1,自引:0,他引:1  
利用2001-2015年松花江流域国家监测网30个可比断面监测数据,从流域和断面水质变化、各项指标超标情况和浓度变化、污染负荷等方面分析了松花江流域水质变化情况。结果表明,松花江流域水质总体呈好转趋势,特别是2007年以来有比较明显的改善。该流域长期以来主要污染指标为高锰酸盐指数、石油类、五日生化需氧量和氨氮。高锰酸盐指数、石油类和五日生化需氧量污染均有明显改善,但氨氮污染改善不明显。在继续加强COD排放总量控制的基础上,有效削减氨氮排放是促进松花江水质改善的重点。  相似文献   

18.
2020年8月15日袁河袁州区段(棚下-袁河水厂取水口)出现溶解氧过饱和现象,为了解该河段溶解氧的变化及提高河道流量前后对水生态环境的影响,将该段河道分为6个监测断面,于8月16—24日监测每个监测点的常规水质、浮游植物群落结构、溶解氧和实时流量.结果表明:自然状态下袁河袁州区段溶解氧沿水流方向从6.8 mg/L逐渐增...  相似文献   

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