河流对阿哈水库汞迁移转化过程的影响

阿哈水库是贵阳市饮用水源,二十世纪九十年代之前阿哈水库流域的煤窑废水污染是其主要污染源;之后,矿山煤窑废水经集中治理,状况得到很大改善,生活水排放成为主要污染源。阿哈水库入库河流总汞浓度为7.1~47.9 ng/L;甲基汞浓度为0.16~2.50 ng/L;活性汞浓度为0.25~2.43 ng/L,且随季节变化明显,枯水期<丰水期。阿哈水库入库河流汞的主要存在形态为颗粒态汞,总汞与颗粒态汞呈显著正相关。阿哈水库唯一的出湖河流小车河中,各种形态的汞均较入湖河流中的汞含量大大减少,这表明水库的沉淀和拦截净化作用相当显著。     

Methylmercury and total mercury distribution in the sediments of Baihua Reservoir, Guizhou Province, China

Mercury is an important pollutant in lakes. Methylmercury （MeHg）, the most toxic mercury species, which can be formed from inorganic mercury in lakes, can be bioaccumulated into high concentration in food chain and result in a potential threat to human beings. Sediments play an important role for the Hg biogeochemistry in the aquatic systems： Mercury methylation has been shown to be fastest in the surfacial sediments, where the microbial activity is highest. The formation of MeHg in lakes suggests that sediments and/or near-shore wetlands can be the sources of MeHg in aquatic environments. The Baihua Reservoir, located in the suburb of Guiyang, was impounded in 1966. From the 1970s to the 1990s, Guizhou Organic Chemical Plant which used inorganic mercury as catalyst to produce acetic acid, was responsible for the discharge of waste water with high mercury content.     

Seasonal distribution of total mercury and methylmercury in sediments of the Wujiangdu Reservoir, Guizhou, China

The concentrations of total mercury and methylmercury in sediments were determined at the dam of the Wujiangdu Reservoir in different seasons. Total mercury (HgT) levels in the whole sediment profile were 254.2±47.0 ng/g in winter, 254.2±31.6 ng/g in spring, and 256.7±60.8 ng/g in summer, without significant variations in different seasons or at different depths. In contrast, the methylmercury (MeHg) compounds were most abundant at the sediment-water interface and decreased progressively with depth. MeHg contents of the sediments during different seasons are highly dependent on microbial activity, and seem to be higher when Hg (II)-methylating microorganisms are active. Thus, MeHg levels tend to rise in the loci where nutrient supplies and biological productivity are favorable. The percentage of HgT that is present as MeHg in the sediments increased gradually from December 2003 to April 2004 and to July 2004.     

Distribution of mercury species in water and sediments in Caohai Lake, Guizhou Province

Caohai Lake which is situated in Guizhou Province, has suffered drain project many times since 1958.The main mercury contamination includes industry waste water, litter and waste residue from refine zinc furnace and so on. The water and sediment samples which were collected from Caohai Lake in different seasons using metal clean protocols. Study sites were selected at the upper and down reaches and the tributaries of this lake, respectively. Total mercury （THg）, reactive mercury （RHg） and dissolved mercury （DHg） concentrations were measured by trap pre-concentration and CVAFS detection methods, and the concentrations of particulate mercury （PHg） are equal to difference of THg and DHg. Total methylmercury （MeH） and dissolved methylmercury （DMeHg） concentrations were measured by GC-CVAFS detection method. Mercury in sediment was measured by AAS method. The results in autumn were obtained as follows： the average concentrations of total mercury, reactive mercury,     

渤海表层悬浮泥沙的空间模态及其时间变化

针对整个渤海海域悬浮泥沙分布全貌研究的不足,基于2000-2004年连续5年的354个SeaWiFS反演的渤海表层悬沙浓度资料,经多年月平均得到其季节变化特征;通过经验正交函数分解,给出其空间模态及时间系数,揭示渤海表层悬浮泥沙的空间分布特征及其随时间的变化。渤海表层悬沙浓度除秦皇岛海域外近岸高,离岸低,辽东湾东岸浓度远大于西岸;冬季浓度最高,春秋次之,除河口海域外夏季浓度最低;河口海域冬夏季均为浓度高值区。经验正交分解显示第一空间模态反映渤海悬沙浓度的总体分布特征,其显著变化周期为12个月,显示渤海表层悬沙的季节变化特征。第二空间模态反映黄河入海径流对渤海表层悬沙浓度分布格局的影响, 其周期为6个月,代表黄河口海域悬沙浓度的变化周期。第三模态显示渤海不同海域悬沙浓度的增加或减小过程并不同步,存在明显的位相差异。     

The Distrbution of Various Mercury Species in Soil

According to the mercury species with different solubilities,the analytical procedure involving sequential chemical extraction has been applied to partitioning the mercury species in soils into seven fractions.Soil samples collected from five localities in different areas (the high-mercury ares.the man-made mercury-polluted area and the reference area)were an alyzed for the seven mercury species.It is found that high mercury contents of soils can be attributed to both man-made pollution and geological processes,but the two kinds of solis show obvious differences in the distribution of their mercury species.     

Spatial and temporal distributions of mercury species and controlling factors in Hongfeng Reservoir, Guizhou, China

The Hongfeng Reservoir was built in 1960 and is an alkaline, hyper-eutrophic and seasonal anoxic reservoir due to the contamination from domestic and industrial wastewaters. The water samples at deferent depths from two sampling sites were collected from November 2003 to September 2004 using metal clean protocols. Total Hg （THg）, reactive Hg （RHg）, dissolved total Hg （DHg）, dissolved gaseous mercury （DGM） were measured by gold trap pre-concentration and CVAFS detection. Methyl mercury was measured by distillation followed by aqueous phase ethylation, precollection on a Tenax, isothermal gas chromatography and cold vapor atomic fluorescence detection. There was no discernible seasonal trend （about 8 ng/L） in THg concentration based on the average information developed during the four cruises except for high concentrations at bottom and water-sediment interface in May and September 2004. On the other hand, particulate mercury （PHg） and methyl mercury have discernible seasonal variability. Proportion of PHg increased from 29% in February 2004 to 50% in May 2004. In November 2003, February and May 2004 methyl mercury concentrations were relative low and increased with depth （from 0.13 to 0.40 ng/L）. In September 2004, methyl mercury concentrations increased from 0.14 ng/L in the epilimnion to 0.99 ng/L in the hypolimnion. DGM concentrations varied from 0.024 to 0.11 ng/L and decreased with depth.     

不平衡输沙含沙量垂线分布研究

采用理论推导和数值计算的方法,进一步研究了不平衡输沙条件下的含沙量垂线分布,首次提出了非饱和泥沙通量的概念及其表达式,推导了不平衡输沙含沙量垂线分布的理论解,包括不平衡输沙含沙量垂线分布指数公式和幂函数公式,以及相应的底部含沙量确定方法。同时利用差分法求解剖面二维扩散方程,得到了不同参数的不平衡输沙含沙量垂线分布。其结果除少数误差稍大外,两种途径得出的含沙量垂线分布彼此符合良好。     

土壤／沉积物中汞污染地球化学及污染防治措施研究

本文综述了汞的来源,介绍了汞的形态及形态分析方法的研究进展,讨论了影响汞吸附和解吸的主要因素,比较了对土壤/沉积物中汞污染进行风险评价的方法,提出了生物修复、减少汞污染的排放等治理我国汞污染的有效措施。最后对汞在土壤/沉积物中的地球化学行为等研究方面进行了展望。     

Distribution and speciation of mercury in the Hongfeng Reservoir,Guizhou Province,China

The water, pore water, sediment, and fish samples were collected from the Hongfeng Reservoir in November 2003 and February 2004 in accordance with trace metal protocols. The average concentrations of total mercury （THg）, dissolved mercury （DHg）, reactive mercury, dissolved gaseous mercury, total methylmercury, and dissolved methylmercury in the water columns were 8.00, 5.70, 0.63, 0.05, 0.16, and 0.07 ng/L, respectively. THg and DHg in the water columns, THg in pore water and THg in lake sediments of the Hongfeng Reservoir showed the level of mercury in the Hongfeng Reservoir was higher than in other natural waters in the world due to the loading of a lot of waste water with relatively high concentrations of mercury, whereas methylmercury concentrations in fish （wet weight） varied from 1.73-51.00 ng/g, much lower than in most remote lakes and reservoirs reported in northern Europe and North America. Methylmercury distributions in pore water and sediments showed methylation occurred mainly in the upper several centimeters of sediment cores in the Hongfeng Reservoir. The concentrations of dissolved organic carbon, total suspended particles, total Hg, and methylmercury were higher at Houwu than those at Daba in November 2003. It is suggested that other pollutants such as N and P from fishing farm and other waste water at Houwu, which resulted in deterioration of water quality, affected the concentrations and distributions of mercury species in the reservoir.     

中国汞的地球化学空间分布特征

20世纪80年代以来中国积累了岩石、土壤和水系沉积物中的大量可靠的汞分析数据和图件,为分析汞的地球化学空间分布特征提供了依据.从空间分布上看,从中国北部到南部,从西部到东部,土壤和水系沉积物中汞的含量背景值逐渐增高,汞在以干旱荒漠区、半干旱荒漠区、黄土地区和高寒山区为主的西部和北部呈低背景,在东部的森林沼泽区和半湿润低山丘陵区为中等背景,在南部的湿润低山丘陵区、热带雨林区和高山峡谷区为高背景,尤其在以云南东南部、贵州、广西西部、湖南西部岩溶区为中心的低温成矿域内,无论岩石、土壤还是水系沉积物,汞含量背景值达到最高.一般情况下,岩石、土壤和水系沉积物之间的汞含量具有继承性,在地理空间分布上呈明显的对栽应关系,并且土壤和水系沉积物之间的汞含量具有相近性,土壤和水系沉积物较岩石更为富集汞.     

Different mercury species in the atmosphere over the municipal solid waste landfills

Mercury （Hg） in atmosphere can indicate the air quality and the intensity of the Hg emission sources, and the potential impact of the emission source on the local, regional, and global environments. Landfill is a place where municipal solid waste is transported, dumped, spread, and buried, during these disposal processes, some Hg contained in the wastes will be released into atmosphere. This paper presents different Hg species in the atmosphere over the near surface at 5 landfills, i.e., 3 landfills in Guiyang and 2 landfills in Wuhan. Besides one operational sanitary landfill, Gaoyan, the other four landfills just present the total gaseous mercury （TGM） over 0.1 m above the ground; in the Gaoyan landfill, TGM was measured at two altitudes, 0.1 m and 2 m, and other Hg species, reactive gaseous mercury （R.GM）, total particulate mercury （TPM）, monomethyl mercury （MMHg） and dimethyl mercury （DMHg） were also monitored at 2 m above the ground. TGM was measured by Tekran 2537A mercury analyzer, RGM was collected by KCl coated denuders, TPM by quartz filters, MMHg absorbed by dilute HCl solution, DMHg absorbed by CarbotrapTM and analyzed by GC-CVAFS. The results showed that the TGM over the closed landfills has an obvious diurnal pattern, with maximum at daytime and minimum during nighttime, which reflects the Hg emission process over the landfill cover surface, the typical average TGM was about 10-30 ng/m^3 at 2 closed landfills, which was several times higher than the global background; at the soil covered part of the active landfills, TGM concentration range and variation are similar to those at the closed landfills; when the weather is clear, the highest TGM appeared at the working face and downwind of the wording face, TGM can reach up to 500 ng/m^3 at these places, but at raining days, there is no distinct discrepancy between TGM measured at the upwind and downwind of the working face.     

Screening Effect of the Diffusive Boundary Layer in Sediments of Lake Aha in the Suburbs of Guiyang City,Guizhou Province

The redox cycle of iron and manganese is a major geochemica process at the boundary layers of lake sediments.Lake Aha,which lies in the suburbs of Guiyang City,Guizhou Province,China,is a medium-sized artificial reservoir with seasonally anoxic hypolimnion,Long-term sedimentary accumulation of iron and manganese resulted in their enrichment in the upper sediments,In the anoxic season,Fe^2 and Mn^2 ,formed by diological oxidation,would diffuse up to overlying waters from sediments.However,the concentration of oxidation,would diffuse up to overlying waters from sediments,However,the concentration of Fe^2 increased later and decreased earlier than that of Mn^2 .Generally,sulfate reduction occurred at 6 cm below the sediment-water interface.Whereas,in the anoxic season.the reduction reached upper sediments,inhibiting the release of Fe^2 ,The Fe concentration of anoxic water is quickly decreased from high to low as a result of reduction of the suplhur system.     

不同来源区洪水对黄河下游流量-含沙量关系的影响

根据1950-1960年及1974-1985年实测洪峰水沙资料,分析了不同来源区洪水对黄河下游花园口、高村、艾山、利津水文站流量 含沙量关系的影响,以河口镇至龙门区间、马莲河和北洛河总来水量占三门峡、黑石关、小董总水量的20%或25%以上作为中游粗沙来源区洪水,以河口镇至龙门区间、马莲河和北洛河总来水量占三门峡、黑石关、小董总水量的20%或25%以下作为细沙来源区或少沙区洪水。这样,黄河下游花园口、高村、艾山、利津水文站平均流量 平均含沙量关系可分为以增加平均含沙量为主和以增加平均流量为主的两个区。同时,河口镇至龙门区间、马莲河和北洛河的洪水,大大增加了黄河下游平均来沙系数和平均含沙量,并导致全下游河段的必然淤积。     

Autumn-winter anomalous variations in bottom water and sediment temperatures in Lake Teletskoe

We discuss the results of bottom temperature monitoring run in October through December 2005 in the deepwater basin of Lake Teletskoe at a lake depth of 320 m using an autonomous recorder. The obtained temperature patterns of water and sediments to a depth of 1.4 m show sudden large changes. Bottom water temperature fluctuated between 2.9 and 4 °C, and the sediment geothermal gradient changed from –360 to +170 mK/m for the period of measurements. Water temperature became 0.6 °C warmer through November and suddenly switched to cooling after 5 December, and the drop reached 1.15 °C for the following 22 days. The change in water temperature caused the respective change in sediments, namely, gave rise to a positive geothermal gradient. Estimating the deep component of geothermal gradient (heat flow) with this climate noise requires a longer experiment of more than one year.     

Analyses of the vertical and temporal distribution of sulfate-reducing bacteria in Lake Aha (China)

In April and September of 2005, two sediment cores were collected from Lake Aha, which is polluted by the acid mine drainage of the mining industries. Sulfate-reducing bacteria (SRB) groups and their quantity were analyzed by using PCR and FISH (fluorescence in situ hybridization), respectively. The results showed that four SRB groups (Desulfotomaculum, Desulfobulbus, Desulfococcus–Desulfonema–Desulfosarcina and Desulfovibrio–Desulfomicrobium) were detected in September, while only three SRB groups (Desulfotomaculum, Desulfobulbus and Desulfococcus–Desulfonema–Desulfosarcina) were detected in April. Desulfovibrio–Desulfomicrobium was not detected and was expected to exist inactively, in April. Meanwhile, the distribution of every SRB group was wider in September than in April. The results indicated that different SRB groups had different vertical and temporal distribution. The vertical and temporal distribution of SRB was mainly in the upper sediments, and the number of SRB groups and quantity were larger in September than in April. It suggested that the environmental conditions of sediments in September were more suitable for SRB. An erratum to this article can be found at     

Environmental impacts of the abandoned mercury mine in Podljubelj, Slovenia

The Podljubelj mercury mine lies in the NW part of Slovenia. The ore is of hydrothermal-vein type. The ore deposit was exploited between the years 1557 and 1902. Total production of the mine was 110000 tons of ore （360 tons of Hg）. A smelter located close to the mine had been in operation since 1855. The waste material from the mine and the smelter was dumped in close vicinity of the mine. Total quantity of the waste has been estimated at 170000 tons. In order to establish environmental impacts, soil and stream sediment samples were investigated. Soil samples were collected at two different depths （horizons A and B） in a 100 m grid within an 88 ha area. In the vast area also 11 samples of stream sediments were considered. Heavy metals were determined by means of cold vapor atomic absorption spectrometry CV-AAS after aqua regia digestion. Based on the chemical analyses of samples, the estimated mercury mean for soils is 3.67 mg/kg （0.35-244 mg/kg） for horizon A and 1.39 mg/kg （0.17-71.7 mg/kg） for horizon B. The estimated mercury mean for stream sediments is 0.64 mg/kg （0.065-1.36 mg/kg）. The concentrations of mercury in soils generally decrease with depth and distance from the mine. The highest content of Hg was determined in a sample taken in the immediate vicinity of the smelter （719 mg/kg）. The results have shown that on the 9 ha of the study area, the contents of Hg in soils exceeded the officially set limit value for soils （10 mg/kg）. High contents of Hg in soil around the abandoned smelter are a consequence of former atmospheric emissions and technological losses. High contents of Hg were also found in the mine and smelter waste dump. At the edges of the study area and in the samples of stream sediments, Hg concentrations are low.     

Source apportionment and distribution of atmospheric mercury in urban Beijing,China

The concentration of gaseous elemental mercury (GEM) in the atmosphere of urban Beijing was measured from October 2003 to September 2004 to investigate the origins and spatial-temporal variations of atmospheric Hg. The mean value of Hg concentration is 17.1 ng·m-3 (n=653). The atmospheric Hg data showed spatial-temporal variations throughout the duration of our observation. The maximum GEM concentration (53.7 ng·m-3) was observed at Gucheng in the western area of urban Beijing. The GEM concentrations increased from the north to the south of the studied area, and were higher in winter than in summer. The highest and lowest monthly averages of GEM concentrations were measured to be 23.3 and 4.1 ng·m-3 in January and July, respectively. In addition, GEM concentrations are higher in the daytime than at night in Autumn and from 14 March to 15 April, but daily GEM variation showed an inverse pattern from 22 April to 22 May. In winter, two peak values of GEM concentrations occurred at 13:30 and 21:30. Daily variation of GEM concentrations in summer was the lowest in the four seasons. Mercury from coal combustion was estimated to be the main source of anthropogenic emissions in Beijing from October 2003 to September 2004. Additionally, Hg emission from natural gas burning was estimated to be another dominant source of atmospheric Hg in Beijing.     

基于GIS的水沙运动模型的开发研究

黄河是我国水利的重要工作对象,针对复杂的数学模型需要一个表现平台对其进行可视化的需求,重点研究如何使各种水沙运动模型信息快速、直观、丰富地表现在GIS平台上.研究的主要模块包括流速场符号化、水文信息分类渲染、流速场动画.     

Seasonal variations of adsorption/desorption equilibrium concentrations of P at water-sediment interface in different trophic states of Taihu Lake, China

Sediment from three different trophic states （Meiliang Bay, Xukou Bay and Gonghu Bay） in spring, summer, autumn and winter were collected and analyzed in Taihu Lake. At the same time, seasonal variations in adsorption/desorption equilibrium were investigated with corresponding sediments from these three trophic states, including adsorption efficiency, adsorption/desorption equilibrium concentration and equilibrium adsorption quantity. Variations of TP and P fractions＇ concentrations in the initial and end of adsorption experiment were also documented in order to find the most active P fractions. The following conclusions were obtained： （1） Concentrations of total phosphorus （TP） and its fractions in the sediments were coincided with the trophic state of corresponding overlying water, Meiliang Bay〉Gonghu Bay〉Xukou Bay. The Meiliang Bay located in the north of Taihu Lake is in the eutrophic state and belong to alga-type lake; the Xukou Bay located in the northeast of Taihu Lake is relatively clean lake region; the Gonghu Bay is located in the east of Taihu Lake is in the meso-trophic state. Fe-P concentrations in the Meiliang Bay, Gonghu By and Xukou Bay account for 35.1%-70.9%, 19.6%-26.8%, 16.5%-34.3% of TP, Ca-P account for 20.6%-43.7%, 40.7%-45.0%, 23.0%-41.1% and OP accounts for 15.3%-20.2%, 28.4%-37.4%, 23.6%-54.3%, which changes obviously in different seasons. Fe-P is the major fraction in the eutrophic lake region, which is significantly correlated with the TP concentrations. （2） Adsorption and desorption processes in these three lake regions varied with season.