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1.
本文主要对青藏高原的各类水体(盐湖、河水、井水、泉水及雪水)和柴达木盆地昆特依盐湖,尕斯库勒盐湖的各类沉积物(石盐、石膏、泥岩、粉砂和砂岩等)中氟的分布规律做了初步研究,发现地表水体中的氟主要受构造地质背景以及气候、水体盐度所制约,沉积物中水溶氟的含量与沉积物颗粒大小成反比,同类沉积物中氟的变化与其沉积时水体的古盐度成正比。  相似文献   

2.
对电解铝厂周边氟污染的环境影响评价   总被引:1,自引:0,他引:1  
通过测定广西某电解铝厂周边大气、土壤和农作物中氟化物含量,对该厂周边的氟化物污染进行了评价,结果表明:电解铝厂周围大气氟污染与采样点的方位成显著相关关系;农作物玉米叶片氟污染主要来自于电解铝厂无组织排放的氟化物,而土壤中总氟含量除受大气中氟化物的影响外,还与当地的地质构造、土壤类型等因素有关,与主导风向无明显的相关关系,土壤中水溶氟含量与采样点到电解铝厂距离呈负相关。  相似文献   

3.
本文对高氟区改水后环境中的氟含量进行了调查分析,其结果是该区已陆续改水,大多数居民已饮用到符合卫生要求的水。但该区地面水是计划供应,再加高氟井水未封闭,因而多数居民自留地仍用高氟水浇灌,故该区土壤、蔬菜氟含量、人群摄氟总量仍高于对照区,而人群摄氟比例由改水前饮水占90.73%改变成食物占72.6%。因此,氟污染源的存在是对病区一大威胁。所以,封闭高氟水源,保证水量充足,是完全控制和消灭地方性氟中毒的根本措施。  相似文献   

4.
饮水氟中毒的防治措施   总被引:2,自引:0,他引:2  
地方性氟中毒是一种主要由饮用水含超量氟引起的世界性病害,各大洲都有分布,涉及的国家及地区较多。在我国,该病的分布很广,受害人数也比较多,其中有的省区病害相当严重,对人民身体健康的损害和对生产力的破坏是很大的。本文从饮用水中氟的来源、存在状态及氟与人体健康的关系,说明地方性氟中毒的病害程度与饮用水中氟的含量高低有直接关系,并根据我国具体情况提出几项切实可行的地方性氟中毒防治措施,最后就做好地方性氟中毒防治工作提出几点建议。  相似文献   

5.
通过对电解铝厂周边一定范围内,受氟污染危害的玉米田的调查和研究,揭示了氟污染对玉米产量和子粒品质的影响。试验的结果表明,电解铝厂的氟污染已导致调查区域范围内(0.5~4km)玉米的产量降低至正常产量的28.21%~85.19%,玉米子粒的营养品质变劣,氟含量严重超标,不宜人畜食用。  相似文献   

6.
氟是地球表面分布最广的元素之一,在构成地壳的各种元素中居第十六位。地壳中氟的含量在270~800ppm。很多氟化物均溶于水,且溶解度较高,这一特性决定了氟有极强的地理迁移能力。因此,土壤、水和动植物体内都含有氟。氟是组成人体的必需的微量元素之一,但摄入过量的氟对健康是有害的。由于某一特定的自然环境中含氟过多,通过饮水或食物长期摄入过量的氟,从而使该地区居民引起的慢性  相似文献   

7.
本文对南广河水体中的砷镉铅铬含量分布特征进行了描述,并探讨了南广河的水质质量。结果表明:南广河从上游到下游水体中污染物含量为增大趋势;在时间上也存在一定的变化,枯水期水体中污染物含量高于平水期和丰水期。目前南广河综合水质质量可满足Ⅱ类水质标准要求。  相似文献   

8.
本文对南广河水体中的砷镉铅铬含量分布特征进行了描述,并探讨了南广河的水质质量。结果表明:南广河从上游到了游水体中污染物含量为增大趋势;在时间上也存在一定的变化,枯水期水体中污染物含量高于水期和丰水期。目前南广河综合水质质量可满足Ⅱ类标准要求。  相似文献   

9.
地方性氟中毒的病区遍布世界各地,是一种严重危害人类健康的地方病。自然界中的氟主要通过饮用水进入人体。我国生活饮用水规定水中氟含量在0.5—1,0毫克/升。然而在阿克苏、石河子、奎屯的一些地区,地下水氟含量在1.2—13毫克/升,个别地区地下水氟含量高达23毫克/升。因此,对含氟水进行净化处理是防治地方性氟中毒的有效途径之一,我们在电凝聚除氟原理的基础  相似文献   

10.
水中氟的测定用比色法手续繁琐,采用离子选择电极测定具有选择性好,快速准确,在总离子强度调节缓冲液中,氯化钠可以调即离子强度,而柠檬酸钠可以消除Fe~(3 ),Al~(3 )的干扰。在pH值为5—6时测定较适宜。天然水中氟含量较低,地面水含氟量一般每升含0.2—0.5毫克之间,自来水中要求含氟量每升不超过1.0毫克,有些地下水含氟量较高,可达每升数毫克。水中氟含量的测定方法有茜索锆比色法,茜素络合剂比色法,对磺基苯偶氮变色酸锆比色法,用比色法测定氟,需要蒸馏或萃取等费时费事,特别是在测定微量的氟时,若蒸镏操作不严密,反而给测定结果带来较大的误差,因此令人感到检洲氟化物快速而可靠的方法颇为重要,采用离子选择电极测定微量的氟化物,方法准确、快速,简便,灵敏度高,不破环试样等优点,所以很快地得到人们的重视,在美国已将氟电极法作为水中氟化物的标准分析方法之一,本文采用标准加入法,使用上海生产PF—1型氟电极,对自贡市釜溪河水中的氟进行测定,现将方法小结如下。  相似文献   

11.
饮用水中可溶性氟化物是公众摄入氟的主要途径,其含量水平影响人体健康。分别于2015~2017年的丰水期和枯水期6次随机采集监测了嘉陵江下游52个饮用水样中氟化物含量,并基于地理信息系统平台和健康风险指数法进行了评价。结果表明,该区域饮用水中氟化物浓度平均为0.20~0.25 mg/L。除2015年部分样点外,其余样点的氟浓度均低于国家标准限值。其年际变化为2015年明显高于2016年和2017年(P<0.05);年内变化为枯水期略高于丰水期。研究表明,研究区饮用水中氟化物不会对人体造成威胁,且有逐年降低的趋势,建议当地居民适当增加氟的摄入量,以降低患龋齿的风险。  相似文献   

12.
山西省某区块煤层气采出水水质均值为COD 170 mg/L,BOD529.7 mg/L,氨氮5.36 mg/L,氟化物6.59 mg/L,4个污染物指标超过GB 3838—2002《地表水环境质量标准》Ⅳ类水质限值要求。文章针对该地区煤层气采出水的可生化性差(BOD5/COD≤20%)、氯离子含量较高等特点,采用“电絮凝+电氧化”法进行中试试验,处理后水质COD≤17 mg/L,氨氮≤0.1 mg/L,氟化物≤1.0 mg/L,试验结果表明:采用该方法可以有效降低COD、氨氮、氟化物等主要污染物指标,使该区块煤层气采出水达到GB 3838—2002标准Ⅳ类水质要求(COD≤30 mg/L、氨氮≤1 mg/L、氟化物≤1 mg/L)。应用中试试验研究成果,采用“双电+保障(过滤)”工艺在该区块建成了煤层气采出水处理示范工程,水处理站建成投运后出水水质稳定,始终满足GB 3838—2002《地表水环境质量标准》Ⅳ类水质要求。  相似文献   

13.
Assistant Professor in Human Ecology, in the Indira Gandhi Centre for Human Ecology, Environment and Population Studies at the University of Rajasthan. Although fluorine is an essential element for human growth and development, its intake in excessive amounts beyond the permissible limits can be very harmful. Dental and skeletal fluorosis are some of the common afflictions of fluorine poisoning and it can even have crippling effects in aged individuals. With the rise in industrialization fluoride contamination is increasing in the human environment as it is a basic component of the ground water. Certain regions of India, particularly the arid zones of Rajasthan, have serious fluoride problems and it has become a serious health hazard in several villages of Rajasthan.  相似文献   

14.
A survey of macro-invertebrates and their monthly variations occupying the Tons river in Doon Valley was conducted from August 2003–July 2004. Macro-invertebrate collections and water samples were taken from three sampling stations every month during the period of study. All the hydrological attributes were measured monthly for 1 year. The present study showed that the water velocity, hydromedian depth, turbidity and dissolved oxygen and nature and size of the bottom substrates do play a major role in determining the macro-invertebrate diversity of Tons river. The ecological relevance of the measured hydrological attributes was investigated by comparing their degree of correlation with invertebrate density and diversity. The Shannon–Wiener index (H′) of macro-invertebrates was found to be highest (3.60) during spring season (February and March) and lowest (2.59) during monsoon season (July and August). The high values of diversity index of macro-invertebrates at all the three sampling sites indicate diverse macro-invertebrate communities in the Tons river in Doon Valley, India.  相似文献   

15.
温泉生态旅游是未来温泉旅游的发展方向。温泉生态旅游非常适合在温泉资源丰富而生态环境较脆弱的喀斯特地区开展。基于对贵州省息烽温泉资源开发利用现状的调查,对息烽温泉生态旅游的发展思路、开发模式和运行机制进行了初步研究,希望能为该区域发展温泉生态旅游提供决策参考。  相似文献   

16.
Fifty percent of the dry zone areas in Sri Lanka have fluoride levels above 1 ppm. This paper discusses the ground conditions and recommends an appropriate range of fluoride in drinking water which can support preventive practices for improving the oral health of children 8-years old and younger. In efforts to address the Chronic Kidney Disease of Unknown etiology (CKDU), water treatment to reduce contaminant level in potable water has been implemented. Such treatment would also remove fluoride and has resulted in potable water with various fluoride levels, depending on concentrations in the raw water. While it is important to reduce fluoride levels, it is important to have appropriate residual levels for prevention of dental caries. It needs, however, to be noted fluoride in excess can cause dental fluorosis. In Sri Lanka's dry zone areas increasing prevalence of dental fluorosis with decreasing prevalence of dental caries has been noted. Consumption of tea and powdered milk could increase total intake of fluoride. Fluoridated toothpaste, when used properly, may, however, result in negligible intake of fluoride. Sri Lanka's hot tropical climate which results in substantial intake of fluids reinforces the need to consider reduction in water fluoride. Consideration of local studies and international standards indicate fluoride levels should be in the range of 0.225–0.500 ppm. In the range of 0.225–0.500 ppm, the prevalence of dental fluorosis and caries was only 14% and 8%, respectively, in an endemic district. When fluoride levels are above 0.500 ppm, the issue of dental fluorosis shall need to be addressed. When levels are below 0.225 ppm, oral health care services shall need to be directed at preventing dental caries.  相似文献   

17.
地下水化学成分受地质、水文地质、岩性等因素的控制,水化学特征研究对水资源的利用、管理及保护具有重要的指导作用。西藏自治区芒康县盐井乡境内,沿澜沧江近岸边长约1.5km范围内出露有50余处矿化度较高、水温为中高温、无色、味咸的天然盐泉。这种地下热卤水的分布特征、水化学特征和化学组分的形成,受地质构造、地下水径流通道、径流速度等条件的影响,因此通过对其水样水化学特征的研究,进一步阐明盐泉形成的基本规律。  相似文献   

18.
Abstract: In the karstic lower Flint River Basin, limestone fracturing, jointing, and subsequent dissolution have resulted in the development of extensive secondary permeability and created a system of major conduits that facilitate the exchange of water between the Upper Floridan aquifer and Flint River. Historical streamflow data from U.S. Geological Survey gaging stations located in Albany and Newton, Georgia, were used to quantify ground‐water and surface‐water exchanges within a 55.3 km section of the Flint River. Using data from 2001, we compared estimates of ground‐water flux using a time adjustment method to a water balance equation and found that these independent approaches yielded similar results. The associated error was relatively large during high streamflow when unsteady conditions prevail, but much lower during droughts. Flow reversals were identified by negative streamflow differences and verified with in situ data from temperature sensors placed inside large spring conduits. Long‐term (13 years) analysis showed negative streamflow differentials (i.e., a losing stream condition) coincided with high river stages and indicated that streamflow intrusion into the aquifer could potentially exceed 150 m3/s. Although frequent negative flow differentials were evident, the Flint River was typically a gaining stream and showed a large net increase in flow between the two gages when examined over the period 1989‐2003. Ground‐water contributions to this stream section averaged 2‐42 m3/s with a mean of 13 m3/s. The highest rate of ground‐water discharge to the Flint River occurred during the spring when regional ground‐water levels peaked following heavy winter and spring rains and corresponding rates of evapotranspiration were low. During periods of extreme drought, ground‐water contributions to the Flint River declined.  相似文献   

19.
本文报道了四川省20市、地、州的环境饮水(自来水、井水及部分江河、湖库、泉水)中之~3H辐射水平、变化规律与分布特点,对其影响因素进行了简要探讨和评价。 3H(氚)是氢的唯一放射性同位素,发射低能炖β粒子,在许多生产和研究领域得到了日益广泛的应用。它是核燃料循环中可能对环境产生较大影响的核素之一,更是未来的能源——可控热核反应堆可能对环境产生影响的主要核素。因此,氚是人们进行核环境评价时感兴趣的主要放射性核素之一。事实上氚,是水体中含量最高的放射性核素。因此,氚在环境水中的现状,以及对氚进行有效的监测监督,已成为人们十分关注的问题。  相似文献   

20.
福建乡村温泉旅游开发模式研究——以闽侯光明温泉为例   总被引:1,自引:0,他引:1  
福建省温泉资源丰富,温泉旅游开发是福建省旅游业近阶段焦点之一.开发模式创新是温泉旅游企业赢得市场竞争,实现永续经营的关键.在总结国内外其他学者对温泉旅游开发模式研究的基础上,从发展推动力、资源利用集约程度、温泉与其他产业的对接、温泉主题文化、温泉度假区代系、温泉企业经营管理等六个方面对温泉旅游开发模式进行了系统解构,以闽侯县光明温泉为例,对福建乡村温泉旅游开发模式选择进行了探讨.  相似文献   

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