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1.
丰水期红枫湖流域氮污染特征的变化规律研究 总被引：4，自引：0，他引：4
丰水期对汇入红枫湖的后六河、麻线河、羊昌河和桃花园河等河水中氮素的形态和含量进行测定,结果表明NO3--N是氮素的主要形态,约占TN的25%~65%;三态氮在空间分布上,从上游至下游,四条河流表现出不同的变化规律,后六河NH4+-N、NO2--N与NO3--N的变化规律基本上一致外,含量总体上逐渐增加;其它三条河流中,NH4+-N与NO3--N的含量呈现相反的变化趋势,NO2--N的变化规律则不明显。该流域整体上表现为非点源污染的特征。后六河和麻线河地下水中NO3--N的含量明显高于相应河水中的含量。该研究对亚热带小流域河水中氮磷含量及形态变化研究具有借鉴意义,对该流域的环境规划、环境管理和环境污染治理具有指导意义。 相似文献
2.
以青藏高原长江源区典型高寒草地小流域为研究对象,基于2012年小流域气象监测数据和小流域径流水样分析,探讨了小流域水体碳氮输出特征,分析了气象因子和土壤水热对小流域水体碳氮输出的影响。结果表明,径流水体碳氮质量浓度均较低,其中可溶性有机碳(DOC)、可溶性有机氮(DON)、铵态氮(NH4+-N)和硝态氮(NO3--N)含量分别在2.95~6.96mg.L-1、0.45~1.15mg.L-1、0.02~0.88mg.L-1和0.16~0.36mg.L-1之间;DOC、DON、NO3--N在8~10月份之间随时间逐渐升高,9月中旬达到峰值后波动下降,NH4+-N无显著的季节变化特征,溶解氮中DONNO3--NNH4+-N;DOC和DON的输出量与降水、不同土层(20、40、60、90、120cm)地温和不同深度(10、20、40、60cm)土壤水分、水温呈极显著正相关(P0.001),与90、120cm土壤水分呈极显著负相关(P0.001);NH4+-N的输出量与降水、气温、水温呈显著正相关(P0.05);NO3--N与降水呈极显著正相关(P0.001)。 相似文献
3.
漓江水系汞的分布和污染研究 总被引：1，自引：0，他引：1
对漓江水系干流、支流、连体湖泊、较大的孤立湖塘和近岸水井设置40个采样点。水样采样周期为2个水文年,分枯水季和丰水季两次采样,现场测定水温、电导率、pH值等理化参数。系统采集水样112件、底泥样40件、水草样40件、近岸土壤样40件。底泥样用逐步浸提法进行不同形态汞分析。研究结果显示,干流河水、底泥和水草中汞的平均含量分别为0．12μg／L、0．20μg／g和0．032μg／g;主要支流河水、底泥和水草中汞的平均含量高于干流,分别为0．15—0．23μg／L、0．38～1．7μg／g和0．028—0．044μg／g。底泥中汞含量均高于近岸土壤汞含量。无论是干流还是支流,河水汞含量与底泥、水草汞含量有明显的相关关系。由上游至下游,漓江水系干流、主要支流河水样汞含量均不断增高,可高出源头河水汞含量的1．5—5倍。相应地指示重金属离子污染的参考指标——电导率值不断增高,河水的pH值亦逐渐增高。丰水期（5月至6月）河水中的汞含量（0．12—0．28μg／L）明显高于枯水期（9月至11月）河水中的汞含量（0．091—0．28μg／L）。不同断面河水汞含量均高于相应近岸井水汞含量。不同水体底泥中汞的形态分布一般顺序为：残渣态〉难氧化降解有机质结合态〉腐殖酸结合态〉碳酸盐和铁锰氧化物吸附态〉交换态〉易氧化降解有机质结合态〉水溶态。综合各项资料分析,认为漓江干流是桂林城市汞污染最大的汇。根据地表水环境质量标准（GB3838--2002）,仅汞而言,漓江水系均达到Ⅳ类水质标准（河水中汞含量≤1μg／L）。漓江支流汞污染高于干流,对干流存在较大的污染风险。 相似文献
4.
喀斯特山区溪流上覆水—孔隙水—沉积物中不同形态氮的赋存特征及其迁移——以麦西河为例 总被引：4，自引：0，他引：4
选取贵州百花湖入湖支流麦西河为对象,研究了上覆水—孔隙水—沉积物体系氮的形态差异,结果表明:麦西河上覆水中,以硝态氮(NO-3-N)为主,氨态氮(NH+4-N)次之,亚硝态氮(NO-2-N)最低;孔隙水中,溶解无机氮中以NH+4-N为主, NO-3-N次之, NO-2-N最低;沉积物中,总氮(TN)的含量为1110.67～4413.16mg/kg;固定态铵含量为34.56～170.05mg/kg,占TN的1.47%～6.25%;可交换态氮以NH+4-N为主, NO-3-N次之, NO-2-N最低。孔隙水NH+4-N是上覆水NH+4-N的2.65～19.51倍,上覆水NO-3-N是孔隙水NO-3-N的7.14～20.43倍。沉积物TN与孔隙溶解水无机氮(DIN)、孔隙水NH+4-N、沉积物可交换态氮和沉积物可交换性NH+4-N呈显著正相关;在沉积物中,可交换性NO-3-N与可交换性NH+4-N及可交换态氮呈显著正相关,可交换性NH+4-N与可交换态氮呈极显著正相关;孔隙水溶解无机氮与孔隙水NH+4-N呈极显著正相关。麦西河不同介质中氮的迁移关系则表现为:由于浓度梯度,上覆水中的NO-3-N扩散到孔隙水中,进而累积到沉积物中;沉积物的可交换性NH+4-N,进入孔隙水,最终扩散到上覆水中。 相似文献
5.
以洮河流域河水为研究对象,通过对2018年每隔1月洮河干流及支流博拉河和广通河采样点的河水进行水化学研究,揭示了洮河流域河水的水化学组成,探讨了其水化学性质时空变化。结果表明：洮河流域水质偏碱性,干流上游pH值小于下游,并在枯水期都比丰水期为大;矿化度呈枯水期比丰水期小,河水属于中等矿化度水和适度硬水;总硬度、电导率呈枯水期比丰水期大;HCO3-、Ca2+、Na+、Cl-、SO42-、CO32-含量呈枯水期比丰水期大;干流上游HCO3-、Ca2+、CO32-含量大于下游,干流上游Mg2+、K+、Na+、Cl-、SO42-、MnO4<... 相似文献
6.
城市地下水硝酸盐污染及其成因分析——以珠海香洲区为例 总被引：7，自引：0，他引：7
为判断华南地区典型城市地下水硝酸盐污染源,采集珠海市香洲城区及周边地区地下水样,并测定NO3-、NH4+、NO2-、PO43-、1δ5N-NO3-以及EC、pH值等。结果显示:在城市区地下水大多数样品中,NO3-是主要的无机氮形态。近40%的水样超过世界卫生组织饮用水标准(NO3--N≤10mg/l),部分井水有NO2-检出,整体污染较为严重。地下水硝酸盐1δ5N落在6.879‰~26.144‰范围内,而生活污水及化粪池泄漏是地下水NO3--N主要污染源。反硝化作用可能是导致雨季地下水1δ5N值升高的重要因素。另外,稀释、混合等作用可能是导致地下水NO3-浓度季节变化复杂的原因。 相似文献
7.
喀斯特山区浅层地下水的季节变化特征及影响因素——以普定后寨河为例 总被引：2，自引：1，他引：1
以贵州中部喀斯特山区普定县后寨河流域浅层地下水为研究对象,对浅层地下水的季节变化特征及影响因素进行分析。结果表明:在喀斯特山区,浅层地下水主要阴离子为HCO3-、SO42-、Cl-,分别占总离子含量的53%、15%、3%,主要阳离子为Ca2+和Mg2+,占总离子含量的19%和6%,水化学类型为HCO3-Ca型水,pH为7.51～8.23,呈微碱性;浅层地下水具有明显的季节变化特征,HCO3-、Na+、NO3--N、Ca2+、TP的季节差异显著（P<0.05）,K+、Mg2+、Cl-、TN、NH4+-N、SO42-不同季节之间存在差异,但未达显著水平。喀斯特山区,浅层地下水化学性质主要由地层岩性决定,对农业活动、居民生活活动响应敏感,其中以农业活动最为显著,居民生活活动次之。喀斯特山区居民的农业活动和人为干扰使得浅层地下水中氮、磷质量浓度升高,明显影响水质。 相似文献
8.
9.
水体中三氮转化规律及影响因素研究 总被引：6，自引：0，他引：6
以城市污染水体为对象,研究了水体中氨氮（NH3-N）、亚硝酸盐氮（NO3^--N）、硝酸盐氮（NO3^-N）的转化及去除规律。结果表明,温度对水体中三氮（氨氮、亚硝酸盐氮、硝酸盐氮）的去除具有重要的影响,在夏季实验中三氮的转化及去除速率明显高于冬季;而在温度相似的情况下,光照则成为影响三氮转化去除速率的决定因素,还发现,在黑暗条件下,水体中亚硝酸盐氮、硝酸盐氮出现明显的累积现象,而在光照情况下则没有。由此推断,在光照条件下藻类生物的同化作用在三氮转化和去除中起了主要作用,藻类生物同化导致的三氮转化和去除速率明显高于硝化-反硝化过程。 相似文献
10.
该文以河南省贾鲁河中牟段为研究区,探究贾鲁河与河岸带浅层地下水的补排关系以及河水对浅层地下水的影响。通
过野外地质调查、水文地质试验、水位监测及水质检测,分析河岸带地表水与地下水的补排关系及污染特征。结果表明,受
中牟县抽取地下水的影响,该河段周围浅层地下水位低于河水位,河流补给地下水,平均单宽补给量为2.04 m2·d-1;河水中
NH3和COD污染较为严重,地下水中“三氮”均超标,其中NO2和NH3污染严重;河水NH3-N浓度远高于地下水,接受河
流补给的地下水NH3污染严重;因硝化作用,远离河流地下水NH3-N浓度逐渐降低,而NO3-N浓度逐渐升高。 相似文献
11.
Based on the observation of a complete hydrological year from June 2014 to May 2015, the temporal and spatial variations of the main inorganic nitrogen(MIN, referring to NO_3~--N, NO_2~--N, NH_4~+-N) in surface water and groundwater of the Li River and the Yuan River wetland succession zones are analyzed. The Li River and the Yuan River are located in agricultural and non-agricultural areas, and this study focus on the influence of surface water level and groundwater depth and precipitation on nitrogen pollution. The results show that NO_3~-N in surface water accounts for 70%-90% of MIN, but it does not exceed the limit of national drinking water surface water standard. Groundwater is seriously polluted by H_4~+-N. Based on the groundwater quality standard of H_4~+-N, the groundwater quality in the Li River exceeds Class III water standard throughout the year, and the exceeding months' proportion of Yuan River reaches 58.3%. Compared with the Yuan River, MIN in groundwater of the Li River shows significant temporal and spatial variations owing to the influence of agricultural fertilization. The correlation between the concentrations of MIN and surface water level is poor, while the fitting effect of quadratic correlation between H_4~+-N concentration and groundwater depth is the best(R~2=0.9384), NO_3~-N is the next(R~2=0.5128), NO_2~--N is the worst(R~2=0.2798). The equation of meteoric water line is δD =7.83δ~(18) O+12.21, indicating that both surface water and groundwater come from atmospheric precipitation. Surface infiltration is the main cause of groundwater H_4~+-N pollution. Rainfall infiltration in non-fertilization seasons reduces groundwater nitrogen pollution, while rainfall leaching farming and fertilization aggravate groundwater nitrogen pollution. 相似文献
12.
Based on the observation of a complete hydrological year from June 2014 to May 2015, the temporal and spatial variations of the main inorganic nitrogen (MIN, referring to NO3--N, NO2--N, NH4+-N) in surface water and groundwater of the Li River and the Yuan River wetland succession zones are analyzed. The Li River and the Yuan River are located in agricultural and non-agricultural areas, and this study focus on the influence of surface water level and groundwater depth and precipitation on nitrogen pollution. The results show that NO3--N in surface water accounts for 70%-90% of MIN, but it does not exceed the limit of national drinking water surface water standard. Groundwater is seriously polluted by NH4+-N. Based on the groundwater quality standard of NH4+-N, the groundwater quality in the Li River exceeds Class III water standard throughout the year, and the exceeding months’ proportion of Yuan River reaches 58.3%. Compared with the Yuan River, MIN in groundwater of the Li River shows significant temporal and spatial variations owing to the influence of agricultural fertilization. The correlation between the concentrations of MIN and surface water level is poor, while the fitting effect of quadratic correlation between NH4+-N concentration and groundwater depth is the best (R2=0.9384), NO3--N is the next (R2=0.5128), NO2--N is the worst (R2=0.2798). The equation of meteoric water line is δD =7.83δ18O+12.21, indicating that both surface water and groundwater come from atmospheric precipitation. Surface infiltration is the main cause of groundwater NH4+-N pollution. Rainfall infiltration in non-fertilization seasons reduces groundwater nitrogen pollution, while rainfall leaching farming and fertilization aggravate groundwater nitrogen pollution. 相似文献
13.
南、北盘江流域枯水期水化学特征及离子来源分析 总被引：1，自引：0，他引：1
为进一步了解珠江上游南、北盘江流域水化学现状,对其枯水期36个河水样品进行水化学特征分析,结果表明:枯水期河水pH值在7.85~8.75之间,呈弱碱性,TDS均值为358 mg·L-1。河水中阴离子组成以HCO3-、SO42-为主,当量浓度占比均值达到65%与26%,阳离子中Ca2+和Mg2+是绝对的优势离子,当量浓度占比均值分别为65%和24%。与丰水期相关研究对比分析发现Ca2+、Mg2+、Na+、SO42-、HCO3-、Cl-的枯水期浓度普遍高于丰水期,K+、NO3-丰、枯水期浓度变化不大。Piper图、岩性端元分析以及离子浓度比值分析表明,研究区水化学主要受碳酸和硫酸共同参与下的碳酸盐岩风化控制。南、北盘江流域都受到农业施用的钾肥和氮肥的影响,此外,北盘江主要受到煤炭开采以及燃煤工业的影响,南盘江主要受到源头及上游河段化工企业废水和沿途市县的生活废水的影响。与前人数据对比发现,15年间人为活动对流域水化学的影响加剧。 相似文献
14.
渭河水质在较大程度上受非点源污染的影响,因此,有必要对其负荷和比重进行研究。2009年至2010年,对渭河干流关中段咸阳和临潼断面进行了洪水期和非洪水期水质水量同步监测。根据监测结果及水文站实测流量资料,分别采用改进的水文分割法和平均浓度法对两断面的非点源污染负荷进行了计算,分析了非点源污染的特点。结果表明:渭河干流关中段主要污染物为COD、NH3-N和TN,两断面洪水期间各指标的平均浓度基本都小于平时的平均浓度;各指标非洪水期浓度变化总体上小于洪水期浓度变化幅度,量级较大的洪水水质变化幅度相对较小;改进的水文分割法和已被检验并被广泛采用的平均浓度法计算结果符合良好。2009年(枯水年,P=68%)渭河咸阳和临潼站各指标非点源污染所占比例基本在20%～30%左右;2009年渭河干流咸阳-临潼河段污染以点源污染为主,构成比例在80%以上。对比2006年(枯水年,P=69%),2009年临潼站COD、NH3-N和TN年点源负荷分别减少11937t、791t和29t,渭河点源治理取得一定成效;此外,临潼站这两年的污染构成比例基本相同。非点源污染在渭河水污染中占较大比重,其对渭河水质的影响不容忽视。 相似文献
15.
Based on the characteristics of land use and drainage network of the upper watershed of the Miyun Res-ervoir, Beijing, 26 monitoring and sampling sites were selected in different sub-catchments. Temporal and spatial variations in nutrient loss were dealt with in this paper in terms of the monitoring data on the water quality of the main tributaries flowing into the Miyun Reservoir. In combination with the monitoring data on water quality, the impacts of watershed characteristics including land-use type, landscape pattern, and drainage density were assessed, The concentrations of nutrients in the rainy season are higher than those in other seasons, and the concentrations of NO3--N are linearly related to those of total N which is the main form of nitrogen present in the fiver water. The concentrations of nitrogen become higher toward the reservoir along the main rivers. The seasonal variation of ni-trogen in the watershed affected by intensive human activities is very obvious; in the watershed with steady or low water flow, the seasonal variation of nitrogen is less obvious. Forest land and grassland can trap and filter nitrogen effectively. Land-use pattern also has important impacts on the loss of nitrogen. The concentrations of nitrogen and phosphorus in the water bodies show great temporal and spatial variations. On a temporal scale, the concentrations of TN and TP in the rainy reason are higher than those in other seasons. On a spatial scale, the concentrations of TN and NO3--N in the Qingshui River and Chaohe River are highest all the time. The spatial variation of TP is distinct, being obvious at sampling sites near villages. The form of nitrogen and phosphorus loss varies in different hydrological seasons. Dissolved nitrogen and phosphorus are the main forms in streams in non-rainy seasons, the dissolved nitro-gen and total nitrogen decrease in percentage in the rainy season. Particulate nitrogen and phosphorus are the main forms in some rivers. The concentrations of TN and NO3--N from orchards and villages are high whereas those from forest land are lowest. Land-use pattern has impacts on TN and NO3--N losses, at the sampling sites near the source landscape, the concentrations are higher than those at the sampling sites near the sink landscape. Water quality of the rivers which flow into the Miyuan Reservior is influenced by the composition of adjacent soils. 相似文献
16.
选择长江中下游49个湖泊进行不同季节的水体溶解无机氮(DIN)、总氮(TN)、总磷(TP),溶解性无机磷(DIP)以及叶绿素a(Chla)等环境参数分析,开展不同营养水平湖泊水体环境变化特征及生物响应机制研究。结果表明:DIN、TN/TP随TP的变化规律反映了不同营养水平和季节下地球化学作用的影响;氨氮(NH4-N)、TP、DIP、Chla尤其是NH4-N的季节性变化规律与营养水平关系密切;TP<0.05 mg/L时,NH4-N随总磷升高的趋势夏季大于其他季节,TN/TP与硝态氮(NO3-N)、TN相关性好,营养源组成和氨化作用是主要影响因素;0.05 mg/L4-N随总磷升高的趋势基本相同,TN/TP与亚硝态氮(NO2-N)、NO3-N、TN相关好,水生植物利用、氨化和反硝化作用是主要影响因素。TP>0.1 mg/L,冬季NH4-N随总磷升高的趋势明显大于其他季节,TN/TP在冬季和春季与TN、NO3-N相关性好,夏季和秋季与TP相关性好,其主要原因在于夏季和秋季水生植物对DIN的利用量、反硝化作用和湖泊内源释放的显著增强。 相似文献
17.
Alicia Kirschbaum Jesica Murray Emilce López Ahinoam Equiza Marcelo Arnosio Geraldo Boaventura 《Environmental Earth Sciences》2012,65(2):493-504
The Yacoraite River and its tributaries run down the eastern slope of the Aguilar Range. It is one of the tributaries of the
Rio Grande, located in Quebrada de Humahuaca, a UNESCO World Heritage site. The Aguilar underground mine (Pb–Ag–Zn) is located
in the upper reaches of the Yacoraite River drainage basin. The aim of this work is to characterize the presence of heavy
metals in water and sediments of the Yacoraite River and to identify their sources. The analysis shows the seasonal variation
of heavy metals concentration in water and their relation with the World Health Organization (WHO) limits established for
human consumption. The Yacoraite basin is naturally anomalous in some metals and some elements, such as As which is controlled
by the chemical composition of regional lithology. During the wet season, Al, Co, Mo and Pb concentrations in water samples
are higher than during the dry season; in addition, these metals are also higher than WHO limit values. High enrichment factors
for Ba, Mo, Pb, Zn and Cd were found in Casa Grande stream, indicating the direct influence of the mining activities. Cd,
Pb and Zn are present in the Aguilar ore minerals, such as sphalerite and galena. Sediments collected during the dry season
show a drastic increase in the concentration of As, Pb, Ba, Zn, Cd and Mn. The Müller geo-accumulation index in Casa Grande
indicates that it is a highly polluted stream. The concentrations of As, Pb, Ba, Zn, Cd are also high in Yacoraite River: Security Quality Guidelines indicates
toxicity. A decrease in enrichment factors and geo-accumulation indices observed in sediments indicates the occurrence of precipitation/adsorption
processes in the river to restore the equilibrium composition. Strict environmental controls in Aguilar Mine are necessary
to avoid the uncontrolled input of toxic metals in Casa Grande stream and Yacoraite River. 相似文献
18.
Issa Sakho Jean-Paul Dupont Mohamed Talla Cisse Sanae El Janyani Soda Loum 《Environmental Earth Sciences》2017,76(6):253
The understanding of the spatial and temporal dynamic of river systems is essential for developing sustainable water resource management plan. For the Senegal River, this subject is very complex according to the context of (1) transboundary basin, (2) several contrasted climatic zones (Guinea, South Sudanian, North Sudanian and Sahelian) with high rainfall variability and (3) high human pressures (dam construction and water uses). From 1954 to 2000, 80% (mean value) of the Senegal River flows recorded downstream part of the basin are provided by three majors tributaries (Bafing, Bakoye and Faléme) located in the upstream part. Then, in our study, this upper Senegal River basin was chosen in order to investigate the hydrological responses to rainfall variability and dam construction. Two nonparametric statistical methods, Mann–Kendall and Hubert test, were used to detect the long-term changes in the time series of precipitation and water discharge (1954–2000) at the annual and seasonal scales. The continuous wavelet transform (Morlet Wavelet) was employed to characterize the different mode in the water discharge variability. Flow duration curve and cumulative curve methods were used to assess the impact of dams on the hydrological regime of the Senegal River. Results showed that the Senegal River flows have been changing under the influence of both rainfall variation and dam construction. The long-term evolution of water discharge depend on long-term rainfall variability: The wet periods of the 1950s and 1960s correspond to periods of higher river flows, while the droughts of the 1970s and 1980s led to unprecedented river flows deficits. The new period, since 1994, show a high inter-annual variability of rainfall and discharge without clear trend. At seasonal scale, the results showed also a strong relationship between rainfall and runoff (R 2 > 0.8) resulting from alternating wet and dry seasons and rapid hydrological responses according to annual rainfall. Nevertheless, the observed flows during dry seasons highlighted the influence of water storage and restitution of infiltrated waters in soils and surficial formations during wet seasons. In the dry seasons, the water budget of the three upstream tributaries showed a water deficit at the downstream gauging station. This deficit was characterized by water loss to underlying aquifers and highlighted the influence of geological setting on water balance. However, in this context, water restitution during the dry season remained dependent on climatic zone and on the total annual rainfall volume during the previous wet season. The results have highlighted an impact of the Manantali dam previously obscured: The dam has no effect on the regulation of high river flows. That is what explains that since its construction in 1988, flooding of coastal cities, like Saint-louis, by seasonal river floods has not ceased. The flooding risk in coastal cities is not avoided, and the dams caused hyper-salinization of the Senegal lower estuary. The breach created in the coastal barrier of the Langue of Barbary in October 2003 promotes direct export of excess floodwater to the sea and reduces this risk of flooding in the delta area. But, this solution led to considerable loss of potential water resources, and the authors recommend a new water management plan with a global focus. However, this study shows the positives impacts of the two dams. They allow the availability of freshwater in order to support agricultural irrigation in the valley and delta zone, in particular during low flows periods. 相似文献