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1.
Chinaisrichinmercuryresources,rankingthirdintheworld .MercuryoresaremostlydepositedinSouthwestandCentralChinalikeGuizhou ,SouthernShaanxi,NorthernHenanandEasternSichuan provinces,particularlyGuizhouwhere 75%mercuryoreofallChinaexists.Annualproductionin 60’sa…  相似文献   

2.
1 IntroductionMercury(Hg)asaglobalpollutanthascausedconcernworldwidesincetheendof 1980s.Itisemittedtotheatmospherefrombothanthropogenicandnaturalsources.Importantsourceoftheformeristhedischargefrom productionanduseofHgaswellasthecombustionoffossilfuels(Nri…  相似文献   

3.
VerticalfluxesofvolatilemercuryoversoilsurfacesinGuizhouProvince,ChinaFengXinbin,ChenYecai,ZhuWeiguoStateKeyLaboratoryofEnvir...  相似文献   

4.
于2012年11~12月采集贵州不同营养状况的6座水库——三板溪水库、龙滩水库、万峰湖水库、百花湖水库、红枫湖水库和阿哈水库水样,分析水体中汞的形态分布及与水体富营养化之间的关系,探讨水体汞形态及其分布特征对水体富营养化的响应.结果表明:6座水库总汞浓度的平均值为(5.82±4.99)ng/L,其中在阿哈水库的库中和百花湖水库的岩脚寨采样点存在不同于其它点的局部污染源;MeHg浓度平均值为(0.08±0.07)ng/L,阿哈水库的MeHg浓度较高是其它水库的2~10倍,约为0.26ng/L.在枯水期,贵州6座水库的富营养化程度不同,其中三板溪水库和龙滩水库为表现为贫营养型;万峰湖水库表现为为贫中营养型;百花湖水库和红枫湖水库表现为为中富营养型;阿哈水库为富营养型.富营养化指数与总汞、甲基汞和溶解态甲基汞皆呈显著正相关(r=0.477,P<0.05; r=0.558, P<0.05;r =0.502, P< 0.05, n=19).富营养化对水库生态系统中形态汞之间的迁移和转化有着重要影响,为溶解态汞和甲基汞的生成提供了有利条件,对水体中汞的地球化学循环的影响不可忽视.  相似文献   

5.
Total mercury in wild fish in Guizhou reservoirs, China   总被引:2,自引:0,他引:2  
The health hazard of mercury (Hg) compounds is internationally recognized, and the main pathways for methylmercury (MeHg) intake in humans are through consumption of food, especially fish. Given the large releases of Hg to the environment in China, combined with the fast development of hydropower, this issue deserves attention. Provided similar mobilization pathways of Hg in China as seen in reservoirs in North America and Europe one should expect increased Hg contamination in relation to future hydropower reservoir construction in this country. This study presents total Hg (THg) concentrations in wild fish from six Guizhou reservoirs, China. The THg concentrations in fish were generally low despite high background levels in the bedrock and depositions from local point sources. The over all mean ± SD concentration of THg was (0.066 ± 0.078) μg/g (n = 235). After adjusting for among-reservoir variation in THg, there were significant differences in THg among functional groups of the fish, assumed to re?ect trophic levels. Predicted THg- concentration ratios, retrieved from a mixed linear model, between the functional groups were 9:4:4:1 for carnivorous, omnivorous, planktivorous and herbivorous fish. This result indicated that MeHg accumulation may prevail even under circumstances with short food chains as in this Chinese water system. No fish exceeded recommended maximum THg limit for human consumption set by World Health Organization and the Standardization Administration of China (0.5 μg/g fish wet weight (ww)). Only six fish (2.5%) exceeded the maximum THg limit set by US Environmental Protection Agency (0.3 μg/g fish ww).  相似文献   

6.
王祖波  何天容 《中国环境科学》2019,39(10):4254-4261
以亚硒酸钠、蒙脱土等作为材料,对蒙脱土进行硒化改性,将硒负载在经过改性的蒙脱土上制备出汞的钝化剂以降低汞和甲基汞(MeHg)在稻米中的富集.将硒化修复剂与污染土壤混合进行浸泡土试验和盆栽试验,分析土壤和稻米中THg和MeHg,探讨不同硒化修复剂对污染土壤中汞的阻控修复效果,并筛选出最佳修复剂.结果表明,4种修复剂均对污染土壤中汞有明显的钝化阻控作用,可显著降低土壤中可交换态汞和甲基汞,降低稻米中THg和MeHg含量.蒙脱土通过不同方式硒化改性后,使蒙脱土结构性能优化,吸附容量增加,并能使硒稳固在蒙脱土上,达到更好的钝化修复效果.硒化壳聚糖改性蒙脱土、亚硒酸钠改性蒙脱土、硒化纤维素改性蒙脱土、硒粉改性蒙脱土4种修复剂稻米THg的降低率依次为81.86%、79.74%、65.69%、61.78%,MeHg降低率依次为89.62%、83.91%、72.93%、63.01%.相比较而言,亚硒酸钠改性蒙脱土修复效果稍低于硒化壳聚糖改性蒙脱土,但其改性方法简单,成本低,更有利于修复剂的推广应用.  相似文献   

7.
松花江水体沉积物汞污染的生态风险   总被引:10,自引:5,他引:10  
为了发展一种方法以便重建河流沉积物中汞的初始背景浓度,并在此基础上评价松花江汞污染现状,于2005年采集了吉林市至哈尔滨市松花江河段沉积物样品,用混合酸消解后,使用原子荧光分析测定了沉积物中总汞含量,使用ICP-MS和ICP-AES分别测定了沉积物中钪和主要阳离子含量.以保守元素钪为基准元素,重建了松花江沉积物中汞的初始背景含量,然后计算了沉积物中汞的富集比率和潜在生态风险指数.结果表明,吉林市至松源河段沉积物汞仍然存在极强的生态污染风险,松源以下河段沉积物中Hg存在中等或轻微生态污染.与以前研究多采用全球工业化前沉积物中汞最高含量或上地壳中汞平均含量来评价沉积物中汞的生态风险相比,本方法比较客观地反映了研究河段沉积物中汞的污染现状和生态风险,建议在沉积物重金属污染评价研究中采用.  相似文献   

8.
Before 1970s the Second Songhua River and Ji Canal of China had been polluted seriously by mercury. During peak pollution period, mercury levels in water, sediment and fish body of these rivers were close to or even higher than that of famous Minamata Bay of Japan. Some residents who live near to the polluted rivers were affected and the methyl mercury values in their blood, hair and urine were higher than normal people obviously . Since the fish had decreased even vanished in these rivers, so the food chain that transfers mercury to human also was out off almostly. However, nervous symptoms of Minamata disease were discovered among fisherman who had eaten more fishes. This report relates the stories about the mercury pollution of the Second Songhua River and Ji Canal.  相似文献   

9.
Spatial distribution patterns of total mercury (THg) in 36 surficial sediment samples representing five regions of Lake Taihu were assessed using the ArcGis geostatistical analyst module. The pollution levels of THg were also evaluated from the same five lake regions. Concentrations of THg were in a ranged of 23-168 ng/g (mean 55 ng/g) in surfical sediments, which was significantly higher than those established baseline levels of the lake. Results of THg indicated that the northern region exhibited notably higher values, the bay regions showed elevated values relative to open areas, and the lakeside regions were higher than those observed in the central area. Lake Taihu suffered moderate to high Hg pollution, and expressed clear Hg enrichment status according to monomial pollution index I geo and human activity factors. The concentrations of THg in the surficial sediments of Lake Taihu showed moderate-strong variation (coefficient of variation 52%). Geostatistical analysis indicated a weak spatial self-correlation, suggesting the contamination of Hg in Lake Taihu is primarily the result of anthropogenic activities.  相似文献   

10.
The adsorption behaviors of Hg(Ⅱ) on laterite from Guizhou Province,China,were studied and the adsorption mechanism was discussed.The results showed that different mineral compositons in the laterite will cause differences in the adsorption capacity of laterite to Hg(Ⅱ).Illite and non-crystalloids are the main contributors to enhancing the adsorption capacity of laterite to Hg(Ⅱ).The pH of the solution is an important factor affecting the adsorption of Hg(Ⅱ) on laterite.The alkalescent environment (pH 7-9) ...  相似文献   

11.
Air pollution control devices (APCDs) are installed at coal-fired power plants for air pollutant regulation. Selective catalytic reduction (SCR) and wet flue gas desulfurization (FGD) systems have the co-benefits of air pollutant and mercury removal. Configuration and operational conditions of APCDs and mercury speciation a ect mercury removal e ciently at coal-fired utilities. The Ontario Hydro Method (OHM) recommended by the U.S. Environmental Protection Agency (EPA) was used to determine mercury speciation simultaneously at five sampling locations through SCR-ESP-FGD at a 190 MW unit. Chlorine in coal had been suggested as a factor a ecting the mercury speciation in flue gas; and low-chlorine coal was purported to produce less oxidized mercury (Hg2+) and more elemental mercury (Hg0) at the SCR inlet compared to higher chlorine coal. SCR could oxidize elemental mercury into oxidized mercury when SCR was in service, and oxidation e ciency reached 71.0%. Therefore, oxidized mercury removal e ciency was enhanced through a wet FGD system. In the non-ozone season, about 89.5%–96.8% of oxidized mercury was controlled, but only 54.9%–68.8% of the total mercury was captured through wet FGD. Oxidized mercury removal e ciency was 95.9%–98.0%, and there was a big di erence in the total mercury removal e ciencies from 78.0% to 90.2% in the ozone season. Mercury mass balance was evaluated to validate reliability of OHM testing data, and the ratio of mercury input in the coal to mercury output at the stack was from 0.84 to 1.08.  相似文献   

12.
在淮南市区40个小学采集楼道、操场及学校临近街道灰尘样品.通过王水水浴-冷原子荧光法测定汞含量,地累积指数法评价其汞污染状况,健康风险模型评估其对儿童的健康风险.结果显示:小学校园及临近街道灰尘中汞含量呈现出:楼道操场街道,分别为0.329、0.164、0.118mg·kg~(-1),各介质中均出现了不同程度汞积累.对于不同功能区,街道灰尘汞呈现出:农业区商业交通区煤矿区废弃煤矿区旅游区;操场灰尘中汞表现为:废弃煤矿区商业交通区旅游区煤矿区农业区;楼道灰尘中汞表现为:商业交通区旅游区煤矿区废弃煤矿区农业区.淮南市燃煤活动对淮南城区小学校园操场和楼道灰尘汞的积累影响较大;从健康风险上而言,灰尘中汞对儿童无显著的非致癌风险,但商业交通区内小学楼道内灰尘汞的暴露量较高,可能会危害儿童健康,需加以重视.  相似文献   

13.
贵州万山汞矿区汞的环境污染及对生态系统的影响   总被引:34,自引:9,他引:34  
通过对贵州万山汞矿地区环境样品(水、土壤、植物、农作物和动物)的系统研究,发现该地区的环境汞污染以土壤、大气污染为主,水体基本处于正常范围.土壤汞含量为24.31~347.52mg·kg-1,比全国土壤平均值高出2~3个数量级;水中汞含量除了冶炼厂荷花池中含量较高外,其它水体为0.10~0.68ng·mL-1.由于矿山长期的开采和冶炼,整个环境的汞污染严重,当地的植被、农作物、动物中存在明显的汞蓄积,各种植物不同部位的汞含量为0.47~331.4mg·kg-1;苔藓可以高度富集汞.  相似文献   

14.
马丽钧  周浪  宋波  王佛鹏  张云霞  吴勇 《环境科学》2023,44(5):2868-2878
贵州省是我国Hg产量和储量最大的省份,玉米是其第二大粮食作物,有必要摸清贵州省土壤Hg含量状况,并评估其玉米生产安全性.在玉米主产区采集了990组土壤-玉米样品和270个土壤单一样品,测定土壤pH、阳离子交换量(CEC)和有机质(SOM)含量,以及土壤和玉米中Hg含量.结果表明,贵州省旱地土壤pH在3.93~9.82之间,ω(SOM)几何均值为27.5 g·kg-1,CEC几何均值为11.7 cmol·kg-1;土壤ω(Hg)范围为0.005~686 mg·kg-1,几何均值为0.632mg·kg-1,样点超标率为7.22%;其中,铜仁市土壤Hg污染最突出,超标率达21.3%;就县级而言,黔东南苗族侗族自治州丹寨县、铜仁市万山区和碧江区土壤Hg点位超标率较高;基于《食品安全国家标准食品中污染物限量》(GB 2762-2017),玉米籽粒Hg含量超标率为1.11%,超标点位主要分布于铜仁市万山区和安顺市西秀区等工矿业活动区周围.由结果可知,贵州省存在土壤Hg污染严重的情况,整体上玉米可实现安全种植,但...  相似文献   

15.
1 Determinationoftotalmercuryandspeciationofmercurycompoundsinatmosphere1.1 DeterminationoftotalmercuryAsamplingtrainconsistingofafiltertoretain particulatephasemercuryfollowedbyanabsorbenttrapwhichretainstotalgaseousmercuryisusedfordeterminationoftota…  相似文献   

16.
利用自动汞分析仪、GC-ECD和原子荧光分析了汞污染暴露1,3,7,20,30,90d后,大鼠脑、肝、肾中的总汞、甲基汞和硒的含量.结果表明,总汞、甲基汞含量随暴露时间的延长而显著增加;各组织对总汞和甲基汞蓄积量的顺序是肾>肝>脑;从甲基汞和总汞的比率分析发现,甲基汞很容易透过血脑屏障,并且在脑中有较高的蓄积;硒能够拮抗汞在脑、肝、肾中的蓄积水平.  相似文献   

17.
贵州省黔西南州晴隆-安龙地区主要贵州"红土型"金矿的主要产区,也是贵州省湿法炼金的主要生产基地,区内金矿生产在一定程度上促进了当地乃至贵州省经济社会的发展,同时也对当地矿山生态环境造成了较大影响,产生很多环境地质问题,矿山矿渣、废渣等产生的环境地质问题尤为突出。为了解该地区矿山有害废物种类、含量变化范围和污染程度及分布,通过对调查区42件矿渣、废渣所含As、Sb、Hg及73件浸出液中As、Sb、Hg、CN-、S2-有害元素分析,确定晴隆、兴仁、安龙各调查区存在的主要的有害元素及污染程度,根据综合污染指数(GTi)划分出中度、轻度污染区域,提出今后该区矿山地质环境恢复治理建议和有待研究的环境地质问题。  相似文献   

18.
山东南四湖沉积物中汞的污染现状及迁移研究   总被引:1,自引:1,他引:1  
通过测定南四湖及其入湖河流沉积物中总汞和形态含量,研究南四湖沉积物中汞的污染现状及空间迁移特征.南四湖表层沉积物中总汞含量为0.046 mg·kg-1,明显高于其环境背景值,表明南四湖受到一定程度的汞污染;沉积物中汞的形态主要以残渣态为主,占总汞含量的65.15%,非残渣态占总汞比例相对较小,依次为有机结合态(30.61%)、可提取态(2.93%)、铁锰氧化态(1.31%),其空间变化为独山湖区和昭阳湖区非残渣态汞含量较低,南阳湖区和微山湖区相对较高,具有一定的潜在生态危害;从水平方向来看,南四湖表层沉积物中汞含量具有明显差异,各湖区污染程度不同,汞在水平方向迁移较明显;垂直方向来看,从柱状沉积物底部到顶部汞的含量呈增加趋势,这可能与不同时期社会经济状况有关.  相似文献   

19.
煤中汞燃烧过程析出规律试验研究   总被引:32,自引:6,他引:32       下载免费PDF全文
在小型煤粉燃烧实验台架上进行煤燃烧后汞的燃烧形态转化试验研究。采样过程利用了美国EPA推荐使用的On-tario-Hydro方法进行煤样燃烧产物的取样。研究认为,煤样燃烧后烟气中的气态汞总量在10-15μg/m^3范围内,其中二价汞在40%左右,较低的烟气冷却速率可以促进单质汞向二价汞的转化、烟气中的气态汞占总汞的70%左右。  相似文献   

20.
云南棕榈藤资源及发展策略   总被引:4,自引:0,他引:4  
云南省具有丰富的棕榈藤种质资源,棕榈藤作为一种重要的非木材植物,不仅在全球生物多样性保护、经济贡献和生态重建等方面起着重要的作用,而且,与当地居民有着密切的联系,为各少数民族创造了财富。然而,随着经济的发展,森林资源减少,环境条件退化,棕榈藤资源日益减少,特别是有些优良棕榈藤种类处于濒危状态。因此,优良棕榈藤的引入、繁殖和栽培,不仅将满足棕榈藤发展的需要,而且亦将扩大良种藤的遗传基因库,为未来棕榈藤资源的进一步开发利用打下坚实的基础。论文基于云南棕榈藤资源发展的要求,对棕榈藤资源现状、利用、发展潜力和策略进行探讨。  相似文献   

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