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1.
元江-红河跨境水质环境问题和保护研究 总被引：1，自引：0，他引：1
在红河干流不同污染流域,设立5个环境监测断面,同时选定人烟稀少、无工业、自然条件良好的李仙江加禾断面为对照。利用1999～2002年对水质影响大的DO、COD、BOD5、NH 3-N、NO3-N、NO 2-N、Cu、Pb、Cd、T-P、石油类及SS 12项污染物,均在枯、丰、平3个不同水期采样监测,将监测结果做数理统计分析,研究污染物的迁移、转化规律,并得出:出境断面NH 3-N平均含量高达0.18～0.86m gL/,T-P高达0.045～0.315m g/L,SS高达69～3412m gL/,从而提出小流域治理、退耕还林、城市水网改造及控制含磷洗涤剂使用的建议。 相似文献
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昆明翠湖水质变化特征及影响因素研究 总被引：6，自引：2，他引：4
翠湖是昆明非常重要的景观水体。通过对翠湖有代表性位点水样及相应底泥样品的采集,翠湖水样及底泥的主要指标进行监测、分析和评价。结果表明：目前翠湖水体（总磷含量0．38mg／L,总氮5．06mg／L,氨氮2．37mg／L）已属富营养化水体;翠湖水体总磷、总氮和氨氮含量随季节呈现明显动态变化,高锰酸盐指数和pH值等含量随季节变化不明显;底泥总磷含量3．02g／kg,速效磷163．29mg／kg,碱解氮493．41mg／kg,水体营养盐和底泥营养盐含量有明显相关性,底泥中营养盐总磷、速效磷和碱解氮含量对水体富营养程度有很大影响。 相似文献
3.
北京官厅水库砷和氨氮分布特征及水质变化 总被引：1，自引：0，他引：1
为研究北京市官厅水库湿地生态系统水环境改善状况,于2011年丰水期(9月)在水库采集表层水样52个,采用便携式水质监测仪和重金属分析仪对水库原典型污染物砷和氨氮的污染情况进行了检测。结果表明,表层水的T、pH、DO、NH4+-N和As5个指标分别为:22.5～25.8℃、8.57～8.98、17～9.61mg/L、0.13～0.36mg/L、1.94～6.52μg/L。同时结合ArcGIS技术对各指标的空间分布特征进行分析,可以看出,表层水DO和As空间分布差异显著(p<0.05),pH和氨氮差异不显著。官厅水库近几年水质有所好转,pH、氨氮转变尤为明显。综合分析可看出,官厅水库水库水质良好,除个别点外,上述指标均符合地表水II类标准。 相似文献
4.
呼伦湖是内蒙古第一大湖,在草原生态环境保护中举足轻重。在气候变化和人类活动的影响下,呼伦湖的水环境状况不容乐观。为了掌握呼伦湖水体的水质状况,在实地采样的基础上,基于地统计学半方差函数理论和GIS克立格空间插值方法,定量分析了呼伦湖水体溶解氧含量的空间变异特征及分布格局。结果表明：溶解氧的半方差拟合最优模型为球面模型,该水质参数具有强烈的空间自相关性;空间分布上,结合地表水环境质量标准,呼伦湖大部分水域的水质为IV类;考虑到鱼类等水生生物的生存需要,呼伦湖整体的溶解氧状况基本适合鱼类的生长,其中比较适合的区域分布在湖中部。 相似文献
5.
L. M. Sorokovikova V. N. Sinyukovich I. V. Tomberg G. I. Popovskaya N. V. Bashenkhaeva N. P. Sez’ko N. A. Zhuchenko 《Geography and Natural Resources》2016,37(3):220-227
Field observations showed that the characteristics of chemical composition of waters and the development of plankton algae in the lakes within the delta of the Selenga river are determined by their flowage. The most open Lake Nekipelovskoe communicates with the Selenga outlets throughout a year, and Lake Zavernyaikha only at the period of an open channel. Lake Semenovskoe and Lake Khlystov Zaton are located in the islands and are isolated from the outlets. According to composition of main ions, the lakes under investigation refer to the hydrocarbonate class, the calcium group. The sum of ions in the water of Lake Nekipelovskoe approaches the one in the Selenga (86?221 mg/dm3), and the highest sums of ions were recorded in the wintertime in the lakes isolated from the outlets (446?743 mg/dm3). The lakes of the delta are characterized by a high trophicity. The maximum concentrations of total phosphorus in Lake Nekipelovskoe and Lake Zavernyaikha were 68 and 122 μg mg/dm3, and in Lake Semenovskoe and Lake Khlystov Zaton ?0.8 and ?0.63 μg mg/dm3, respectively. The most intense development of algae is observed in Lake Zavernyaikha, which is due to the high population of Baikal endemics. Lake Zavernyaikha showed a close negative correlation between the concentration of NO 3 ? , mineral phosphorus and phytoplankton biomass; the correlation coefficient was ?0.8 and ?0.63, respectively. The lakes exhibited increased contents readily hydrolysable organic matter, and a decrease in dissolved oxygen concentration in winter; hydrogen sulfide was repeatedly recorded in Lake Khlystov Zaton. The water quality in the lakes during the springtime varies from “quite clean” to “weakly polluted”; at low-water periods, especially in winters, it can drop to the category of “exceedingly dirty”. The water quality of the Selenga can be influenced by the lakes during spring floods when material accumulated during the wintertime is transported to the river outlets and further to Lake Baikal. 相似文献
6.
WANG Lei ZHANG Guang-Xin 《湿地科学》2006,4(3):193-197
1 INTRODUCTIONNitrogen and phosphorus in the water are the nu-trients limited in natural wetlands,which seriously in-fluence on the ecosystem production and the biodiver-sity(Mitsch,Grosselin,2000).Nitrogen and phos-phorus recycles have been interrupted b… 相似文献
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滹沱河流域本底状态地表水氮、磷非点源污染评价 总被引：2，自引：0，他引：2
通过对滹沱河流域各支流源头区地表水中氮、磷浓度监测分析,得出本底状态下总氮浓度为0.223～5.631 mg/L,氨氮浓度范围为未检出～0.634 mg/L,可溶态氮浓度为0.190～5.532 mg/L,总磷浓度为0.024～0.683 mg/L,可溶态磷浓度为0.026～0.220 mg/L.本底状态下各水文期氮的非点源污染形态都以可溶态氮为主;磷的非点源污染形态枯水期以可溶态磷居多,丰水期以颗粒态磷为主.滹沱河流域本底状态下氮、磷非点源污染水平较高. 相似文献
10.
本文报道了1999年12月-2000年3月期间南极长城站码头叶绿素a的含量及变化,调查期间叶绿素a含量较高,平均值为2.16mg/m3,变化范围为0.60-7.67mg/m3。高值出现在月初和月中,低值出现在月上旬,这是潮汐所至。而营养盐的含量较高且变化较大,但PO4P的含量较低,且变化不明显。营养盐的浓度由高到低依次为NO3N>NH4N>NO2N>PO4P。 相似文献
11.
Chrysophyte cysts preserved in recent and pre-industrial lake sediment samples from 54 Muskoka-Haliburton (Ontario) lakes were used in a paleolimnological study to determine the impact of acidic precipitation and cottage development on water quality. A total of 246 cyst morphotypes were identified. Ecological preferences of cyst morphotypes were determined using multivariate statistical analysis, cluster analysis, and species-environment correlations. Recent cyst assemblages were related to water chemistry and lake morphometric variables using Redundancy Analysis (RDA). The distribution of morphotypes was related to a gradient of acid neutralising capacity (ANC), expressed through the association of variables related to buffering (i.e. longitude, watershed area, and ionic concentration) with the first axis (1 = 0.29). Cyst assemblages were also defined, to a lesser extent (2 = 0.06), by a trophic status gradient, created through the combination of total nitrogen (TN), total phosphorus (TP), volume-weighted cottage density, and lake depth variables. The identification of lakewater pH and trophic status as important determinants of cyst assemblage structure allowed for the reconstruction of acidification and eutrophication related water chemistry changes using fossil cyst assemblages. The reconstruction of pre-industrial (pre-1850) water quality conditions with fossil cyst assemblages indicated that pH significantly decreased in 24.1% of the study lakes and increased in 16.7% of the lakes. Increases in pH in more alkaline drainage basins are attributed to alkalinity generation processes induced by acidic precipitation as has been shown in other studies. Total phosphorus (TP) concentrations significantly declined in 12.9% of the lakes and increased in 16.6% of lakes. Increases in [TP] were linked to cottage development. Decreases in trophic status may be due to landuse changes, the result of the acidification occurring in the area, or warmer and drier climates. A comparison of chrysophyte cyst and diatom water quality inferences show similar trends in pH changes. There is a good agreement between diatom and chrysophyte bioindicators with respect to [TP] changes in oligotrophic lakes (< 10 g/L); however, diatom inferences suggest that lakes with current [TP] values greater than 10 g/L have decreased in trophic status over time, while chrysophyte reconstructions suggest that these same lakes have become more productive systems. 相似文献
12.
Robert B. Cook Russell G. Kreis Jr. John C. Kingston Keith E. Camburn Stephen A. Norton Myron J. Mitchell Brian Fry Linda C. K. Shane 《Journal of Paleolimnology》1990,3(1):13-34
McNearney Lake is an acidic (pH=4.4) lake in the Upper Peninsula of Michigan with low acid neutralizing capacity (ANC=-38 eq L-1) and high SO
inf4
sup2-
and aluminium concentrations. Oligotrophy is indicated by high Secchi transparency and by low chlorophyll a, total phosphorus, and total nitrogen concentrations. The lake water is currently acidic because base cations are supplied to the lake water at a low rate and because SO
inf4
sup2-
from atmospheric deposition was not appreciably retained by the lake sediments or watershed and was present in the water column.This interdisciplinary paleolimnological study indicates that McNearney Lake is naturally acidic and has been so since at least 4000 years B.P., as determined from inferred-pH techniques based on contemporary diatom-pH relationships. Predicted pH values ranged from 4.7 to 5.0 over the 4000-year stratigraphy. Considerable shifts in species composition and abundance were observed in diatom stratigraphy, but present-day distributions indicate that all abundant taxa most frequently occur under acidic conditions, suggesting that factors other than pH are responsible for the shifts. The diatom-inferred pH technique as applied to McNearney Lake has too large an uncertainly and is not sensitive enough to determine the subtle recent changes in lakewater pH expected from changes in atmospheric deposition because: (1) McNearney Lake has the lowest pH in the contemporary diatom data set in the region and confidence intervals for pH predictions increase at the extremes of regressions; (2) other factors in addition to pH may be responsible for the diatom species distribution in the lake and in the entire northern Great Lakes region; (3) McNearney Lake has a well-buffered pH as a consequence of its low pH and high aluminium concentrations and is not expected to exhibit a large pH change as a result of changes in atmospheric deposition; and (4) atmospheric deposition in the region is modest and would not cause a pH shift large enough to be discernable in McNearney Lake.Elevated atmospheric deposition is indicated in recent sediments by Pb, V, and polycyclic aromatic hydrocarbon accumulation rates and to a lesser extent by those of Cu and Zn; however, these accumulation rates are substantially lower than those observed for acidified lakes in the northeastern United States. Although atmospheric loadings of materials associated with fossil fuel combustion have recently increased to McNearney Lake and apparently are continuing, the present study of the diatom subfossil record does not indicate a distinct, recent acidification (pH decrease).Order of the first two authors is alphabetical 相似文献
13.
洪泽湖不同湖区表层沉积物对磷的吸附特征 总被引：1，自引：0，他引：1
研究了洪泽湖9 个湖区表层沉积物对磷的吸附行为和沉积物对磷的吸附/解吸平衡质量浓度, 并分析了沉积物理化性质与磷吸附特征参数的关系。结果表明, 在低磷浓度条件下(0~1 mg/L), 沉积物对磷的最大吸附量为50.67~85.17 mg/kg, 沉积物在磷酸盐初始质量浓度较低时都存在负吸附(释放)现象。各湖区沉积物的吸附/解吸平衡磷浓度(EPC0) 范围为0.06~0.11mg/L, 均小于其上覆水中磷的含量, 沉积物对其上覆水中的磷表现为吸附作用。沉积物最大磷吸附量(Qmax)、本底吸附态磷量(NAP) 和总最大吸附磷量(TQmax) 与沉积物中活性铁和活性铝的含量显著正相关, 与沉积物中总磷、无机磷、有机磷和有机质的含量相关性不显著。吸附/解吸平衡浓度(EPC0) 与沉积物各理化参数之间没有表现出显著相关性。 相似文献
14.
《地理学报(英文版)》2019,(3)
The Interconnected River System Network (IRSN) plays a crucial role in water resource allocation, water ecological restoration and water quality improvement. It has become a key part of the urban lake management. An evaluation methodology system for IRSN project can provide important guidance for the selection of different water diversion schemes. However, few if any comprehensive evaluation systems have been developed to evaluate the hydrodynamics and water quality of connected lakes. This study developed a comprehensive evaluation system based on multi-indexes including aspects of water hydrodynamics, water quality and socioeconomics. A two-dimensional (2-D) mathematical hydrodynamics and water quality model was built, using NH_3-N, TN and TP as water quality index. The IRSN project in Tangxun Lake group was used as a testbed here, and five water diversion schemes were simulated and evaluated. Results showed that the IRSN project can improve the water fluidity and the water quality obviously after a short time of water diversion, while the improvement rates decreased gradually as the water diversion went on. Among these five schemes, Scheme V showed the most noticeable improvement in hydrodynamics and water quality, and brought the most economic benefits. This comprehensive evaluation method can provide useful reference for the implementation of other similar IRSN projects. 相似文献
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基于SCS和USLE的程海总磷总氮参照状态推断 总被引：2，自引：0，他引：2
将流域入湖的氮磷负荷分为点源和非点源两部分,基于SCS模型和USLE模型,分别计算流域入湖的溶解态和颗粒态非点源负荷,根据工业、城镇生活及规模养殖废水排放,计算了流域入湖的点源负荷。通过计算的入湖负荷和现有的湖泊氮磷浓度数据,建立了湖泊氮磷质量守恒模型。根据计算的逐年入湖氮磷负荷和建立的湖泊氮磷质量守恒模型,逆推逐年的湖泊氮磷浓度,确定湖泊氮磷参照状态。应用建立的模型推断程海的TP、TN参照状态分别为0.014 mg/L和0.247 mg/L。构建的湖泊氮磷参照状态推断模型,所需资料少,概念清晰,在资料缺乏的其他湖泊流域具有推广应用价值。 相似文献
16.
《地理学报(英文版)》2017,(6)
Since the construction of the Three Gorges Dam,the Poyang Lake hydrological characteristics obviously changed.During the impoundment period of the Three Gorges Reservoir,the hydrodynamic factors of Poyang Lake varied.Water level dropped,the velocity decreased and water exchange time lengthened,which changed the release of phosphorous from sediments.In order to investigate how the hydrodynamic factors influence the release of phosphorous from sediments,we used a two-way annular flume device to simulate the release characteristics of phosphorous from sediments under variable water levels and velocities.We found that both water level rising and velocity increasing could enhance the disturbance intensity to sediments,which caused the increase of suspended solids(SS)concentration,total phosphorus(TP)concentration in the overlying water,and the ability that phosphorus released to overlying water from sediments enhanced as well:when overlying water velocity maintained 0.3 m/s,SS concentration increased to 4035.85 mg/L at the water level25 cm which was about 25 times compared to the minimum value and TP concentration in the overlying water also reached the maximum value at the water level 25 cm which was 1.2times that of the value at 10 cm;when water level maintained 15 cm,SS concentration increased to 4363.35 mg/L at the velocity of 0.5 m/s which was about 28 times compared to the value of 0 m/s,and TP concentration in the overlying water increased from 0.11 mg/L to 0.44mg/L.When the water level maintained 15 cm,the phosphorous release rate reached the maximum value of 4.86 mg/(md)at 0.4 m/s.The concentration of total dissolved phosphorous(TDP)and soluble reactive phosphate(SRP)both in overlying water and sediment-water interface were negatively correlated with p H.Using the parabolic equation,the optimum water level at a velocity of 0.3 m/s was calculated to be 0.57 cm,and the optimum velocity at water level of 15 cm was found to be 0.2 m/s. 相似文献
17.
2010年、20111年和2012年7月对北京翠湖湿地水环境进行跟踪调查与监测,评估湿地恢复之后翠湖湿地水环境的改善效果。恢复区水体pH值、总氮(TN)、总磷(TP)、电导率(EC)和溶解氧(DO)等指标在3年间都表现为下降趋势。其中,pH值从2010年的8.36降到2012年的7.44;TN从2010年的1.94 mg/L降到2012年的1.76 mg/L;TP从2010年的0.129 mg/L降到2012年的0.117 mg/L。说明翠湖湿地经过湿地恢复后,总氮(TN)、总磷(TP)去除效果明显,湿地水环境良好改善,水体自净能力得到加强。本研究可为湿地水环境恢复评估及管理提供一定的科学依据。 相似文献
18.
乌梁素海氮污染及其空间分布格局 总被引：24，自引：0，他引：24
针对草型富营养化湖泊乌梁素海富营养化日趋严重和湿地面积逐渐萎缩的现实,本文系统地研究了TN、NH4+-N、NO3--N和Org-N在上覆水与沉积物中的分布规律。结果表明,上覆水中TN含量平均为1.78mg/L,且无机氮污染以NH4+-N为主,占无机氮总量的69%以上;表层沉积物中氮素的水平分布格局均体现出西高东低的经向分异特征并主要以Org-N的形式存在;表层沉积物中TN对底栖生物已经具有一定的生态毒性效应并正由最低级向严重级过渡;氮素在乌梁素海沉积剖面上均表现出随深度增加而含量递减的规律,表层010cm的TN平均含量达到1.28g/kg,分别为1022cm和2240cm的1.6和1.9倍,揭示了乌梁素海富营养化进程加速始于20世纪90年代。 相似文献
19.
Since the construction of the Three Gorges Dam, the Poyang Lake hydrological characteristics obviously changed. During the impoundment period of the Three Gorges Reservoir, the hydrodynamic factors of Poyang Lake varied. Water level dropped, the velocity decreased and water exchange time lengthened, which changed the release of phosphorous from sediments. In order to investigate how the hydrodynamic factors influence the release of phosphorous from sediments, we used a two-way annular flume device to simulate the release characteristics of phosphorous from sediments under variable water levels and velocities. We found that both water level rising and velocity increasing could enhance the disturbance intensity to sediments, which caused the increase of suspended solids (SS) concentration, total phosphorus (TP) concentration in the overlying water, and the ability that phosphorus released to overlying water from sediments enhanced as well: when overlying water velocity maintained 0.3 m/s, SS concentration increased to 4035.85 mg/L at the water level 25 cm which was about 25 times compared to the minimum value and TP concentration in the overlying water also reached the maximum value at the water level 25 cm which was 1.2 times that of the value at 10 cm; when water level maintained 15 cm, SS concentration increased to 4363.35 mg/L at the velocity of 0.5 m/s which was about 28 times compared to the value of 0 m/s, and TP concentration in the overlying water increased from 0.11 mg/L to 0.44 mg/L. When the water level maintained 15 cm, the phosphorous release rate reached the maximum value of 4.86 mg/(md) at 0.4 m/s. The concentration of total dissolved phosphorous (TDP) and soluble reactive phosphate (SRP) both in overlying water and sediment-water interface were negatively correlated with pH. Using the parabolic equation, the optimum water level at a velocity of 0.3 m/s was calculated to be 0.57 cm, and the optimum velocity at water level of 15 cm was found to be 0.2 m/s. 相似文献
20.
特枯水情对长江中下游悬浮泥沙的影响 总被引：3，自引：0，他引：3
基于长江中下游气象资料、历史水沙资料和2006 年10 月现场水沙观测资料, 分析了 典型枯水年大通站的月均径流量和输沙率特征、2006 年特枯水情产生的气候背景以及对长江中下游含沙量和悬沙粒径产生的影响。分析表明, 枯水年长江干流输沙量有显著的减少, 2006 年特枯水情下大通站汛期输沙量仅占多年平均值(1985-2000 年) 的19.8%。在特枯水情 和三峡工程蓄水的背景下, 2006 年10 月长江中下游含沙量平均为0.057 kg/m3, 只占 2003-2005 年10 月平均值的20.6%。2006 年10 月长江中下游悬沙中值粒径平均为4.8 µm, 悬沙中值粒径只占多年平均值的26.3%, 占近期平均值的41.8%。含沙量、悬沙粒度和中游 河床冲淤特性的综合分析表明, 城陵矶-湖口河段水沙垂向交换强, 是三峡兴建以后近期河 道调整频繁的河段。洞庭湖和鄱阳湖对长江干流含沙量的贡献较大, 尤以鄱阳湖的贡献最大, 长江中下游其他支流对长江干流含沙量的贡献较小。汉江和巢湖对长江中下游悬沙粒径的影响相对较大, 而洞庭湖和鄱阳湖则对悬沙粒径的影响相对较小。 相似文献