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1.
根据高氟地区大面积饮用水及土壤深层及表层水溶氟单位面积随机取样分析含氟量,应用数理统计显著性检验方法检验,进取对照区及实验点在青铜峡高氟地区是可行的。通过大动物-绵羊野外放牧等实验,搞清了青铜峡地区的饮用水和土壤水溶氟的本底值;同时分清了工业氟污染及自然高氟污染对畜牧业的危害所占的比例。  相似文献   

2.
大气氟污染的植物监测的研究   总被引:8,自引:0,他引:8  
本文对大气氟污染与植物叶片中含氟量之间的关系进行了研究,结果表明:(1)一定时间内大气中氟浓度与植物叶片的吸氟量和积累量呈正相关,且相关关系极显著;(2)植物叶片中的含氟量与测定点距污染源的距离呈负相关,距污染源越远在一定时间内植物叶片中含氟量和氟的积累量越低,依此可将污染区划分成严重污染区、中度污染区、轻度污染区和相对清洁区四类;(3)在树木生长期(5~9月份)内,叶片中的含氟量随生长时间的增加呈直线上升趋势。  相似文献   

3.
高氟水沸石除氟的效果研究   总被引:2,自引:0,他引:2  
通过静态搅拌实验和恒温震荡实验,研究了接触时间、pH、温度及反复使用次数对沸石除氟效果的影响.结果表明,在适宜的条件下,沸石除氟效果随着使用次数的增多有上升趋势,除氟效果良好,适用于我国高氟水地区.  相似文献   

4.
高氟饮用水脱氟技术   总被引:2,自引:0,他引:2  
综合了国内目前使用的高氟饮用水脱氟技术,重点介绍两种已用于设备制作的脱氟技术--活性氧化铝和活化沸石。目的介绍了于高氟地区。对饮用水进行脱氟,对氟的地方病进行治理。  相似文献   

5.
安徽淮北平原浅层水中氟的调查分析及建议对策   总被引:1,自引:1,他引:0  
以安徽淮北平原浅层水中与人体健康密切相关的氟元素为研究对象,通过现场调查、采样、测试、分析,得出研究区浅层水中的氟含量在平面分布上,具有由中部向西北部渐高,向东南部渐低的变化特征;在垂向分布上,总体看随深度呈现先增大后减小的变化趋势,以26~30 m范围均值点为临界点,其均值为2.19 mg/L。根据水样中氟含量的高低,将采样区划分为Ⅰ、Ⅱ、Ⅲ三个等级高氟水区和非超标区。探讨了浅层水中氟的影响因子,认为高氟水主要是由自然条件形成。针对采样区浅层高氟水改水现状和存在问题,提出具体建议对策。  相似文献   

6.
调查研究了塔里木河干流流域地下水中氟的含量水平及分布特征.揭示了地下水中氟与水化学性质之间的相互关系。探讨其形成高氟地下水的环境因素,并提出改水防病措施.  相似文献   

7.
一、材料与方法 1.环境样品:牧草生长未期在氟污染牧场同步采集29个点的牧草、土壤样品。测定带尘牧草、水洗牧草、土壤样品的全氟含量。用石灰滤纸法在其中22个牧草采样点测定5个月的大气氟浓度,计算出青草期大气氟平均值。研究环境中各因子之间相互关系。 2.动物样品:以本地区牧业主体山羊为观察动物,选择5个羊群,以其中半岁羊牙齿出现明显损伤为标准,统计羊群发病率。并计算各点青草期(5个月)牧草氟含量月均值。研究环境含氟水平与氟对动物损伤的关系。 在若干放牧点随机取25只羊,38头牛、12匹马、驴骨、蹄壳样品。分别测定骨、蹄壳氟含量。  相似文献   

8.
大气氟污染对水稻产量影响的初步调查   总被引:2,自引:0,他引:2  
大气中氟化物不仅对人体健康有影响,对农作物的生长也有一定危害,江苏、浙江等蚕桑地区,由于砖瓦窑排放大量氟化物,桑叶含氟量明显升高,使蚕茧减产。磷肥厂附近,因氟的污染,也常使粮食减产。 大气中氟化物对玉米、麦类、棉花的危害国内外已有很多人做过很多研究。一般认为、氟化物的毒性比二氧化硫大几十到几百倍。但氟化物对水稻产量的具体影响,尚未见详细报导。为了查清大气中氟化物对水稻产量的影响,防治氟污染,并为处理污染纠纷提供科学依据,我们对某磷肥厂附近水稻生长情况进行实地调查。  相似文献   

9.
离子选择电极法测定土壤中水溶性氟   总被引:3,自引:0,他引:3       下载免费PDF全文
阐述了离子选择电极法测定土壤中水溶性氟的方法。进行了缓冲液用量、浸取时间,水土比等条件实验。该方法精密度好、准确度高,适用于不同类型的土壤中水溶性氟的测定。  相似文献   

10.
青铜峡铝厂氟污染对广武乡玉米影响的调查分析   总被引:1,自引:0,他引:1  
监测了青铜峡铝厂东南方向4.5km的广武乡玉米叶,得知含氟量为43.94-166.1mg/kg,对照样品树新林场玉米叶的含氟均值为13.15mg/kg,广武乡的玉米受到了严重的氟污染,农作物减产严重。  相似文献   

11.
Some issues of environmental concern in Kampala,the capital city of Uganda   总被引:1,自引:0,他引:1  
Kampala, the capital city of Uganda is the administrative, political, commercial, industrial, educational and cultural centre of Uganda. The city has an area of 190 km2 and is located 8 km north of Lake Victoria (the second largest fresh water lake in the world) and approximately 42 km north of the equator. The population varies from about 1.2 million during the day to perhaps 0.9 million at night. The anthropogenic activityof this population far exceeds the infrastructure capacity of the city, leading to the deterioration of the urban environment. This article highlights the major sources of environmental degradation and pollution in the city, which include solid waste,abattoir waste, sewage, sanitation, drainage, industrial pollution, traffic pollution, atmospheric pollution, urban agriculture, rapid urbanisation and water hyacinth.  相似文献   

12.
Access to safe drinking water is an important issue of health and development at national, regional, and local levels. The concept of safe drinking water assumes greater significance in countries like India where the majority of the population lives in villages with bare infrastructures and poor sanitation facilities. This review presents an overview of drinking water quality in rural habitations of northern Rajasthan, India. Although fluoride is an endemic problem to the groundwater of this region, recently, other anthropogenic chemicals has also been reported in the local groundwater. Recent case studies indicate that about 95% of sites of this region contain a higher fluoride level in groundwater than the maximum permissible limit as decided by the Bureau of Indian Standards. Nitrate (as NO $_{3}^{\,\,-})$ contamination has appeared as another anthropogenic threat to some intensively cultivable rural habitations of this region. Biological contamination has appeared as another issue of unsafe drinking water resources in rural areas of the state. Recent studies have claimed a wide variety of pathogenic bacteria including members of the family Enterobacteriaceae in local drinking water resources. Overall, the quality of drinking water in this area is not up to the safe level, and much work is still required to establish a safe drinking water supply program in this area.  相似文献   

13.
再生水作为改善城市景观用水纳入河道,可其对地下水具有潜在的污染风险。通过构建区域地下水数值模型,应用质点追踪技术,计算出永定河补水区在河湖受水后地下水5 a运移1.47 km、20 a运移6.32 km,年均运移0.32 km。在数值模拟的基础上,依据地下水运移轨迹,结合区域水文地质条件,将研究区划分为核心监控区、二级监控区和控制监控区3个地下水监测分区,并提出各分区地下水监测井的布设原则及布设方式,实现地下水环境监测网络的优化。  相似文献   

14.
为了了解塔里木河下游9次应急输水的生态环境效益,利用MODIS—NDVI最大合成法、差值法,分析了塔里木河下游植被指数的年际变化情况,结果表明:(1)塔里木河下游地区植被覆盖度变化中增加区面积呈增加趋势。(2)2002年与输水初期相比,植被覆盖度增加区主要分布于上段和中段的老塔里木河及其文阔尔河河道两侧,下段河道覆盖度增加区仅零星分布于距河道0.3km左右的地势低洼区域。2003年以后,下段植被覆盖度增加区面积已达84.30km^2,是2002年的3.16倍,主要分布在距离河道0.5km左右的河道两侧。至2007年塔里木河下游河道两侧植被覆盖度增加区的变化是比较显著的,特别是下段植被覆盖增加区呈带状分布于距河道1.5km左右的范围内。植被指数遥感监测说明塔里木河下游地区的生态环境得到明显改善。  相似文献   

15.
This study assesses the occurrence of nitrate in the groundwater beneath the R'mel area of the Loukkos perimeter (north-west Morocco), which covers an approximate area of 2,560 km2 and is located between the towns of Ksar el Kebir and Larache. It also borders the Atlantic Ocean. Groundwater supplies are the principal source of drinking water in this region and there is no public drinking water network in the rural area. This perimeter has a population of about 500,000 inhabitants of which the rural population represents 60%, many of whom have depended on and used the water from the aquifers for many years. The inhabitants and farmers depend on the groundwater supplies for drinking water, crop irrigation and other uses. The plain provides the ideal conditions for agriculture and the use of chemical fertilisers has been increasing. In this study, 53 water samples were collected from wells and springs. Each well or spring was sampled once or twice during 1998-2000. Nitrate concentrations ranged from extremely low up to 144 mg L(-1). Nitrate concentrations exceeded the maximum contaminant level (MCL) of 50 mg L(-1) in 12 of the 53 groundwater samples (23%), whereas 31 of the 53 samples (58%) had nitrate concentrations of less than 25 mg L(-1).  相似文献   

16.
东沙沙洲离岸潮间带风电场建设对鸟类的影响   总被引:2,自引:1,他引:1  
对东沙沙洲离岸潮间带风电场的建设给鸟类造成的影响进行了调查。分析表明,噪声对东沙沙洲迁徙鸟类影响不大;光对夜间迁徙鸟类造成一定的影响;风机对候鸟迁徙影响不大,少数低飞候鸟可能存在撞机风险;风机基础和人工岛的永久占地造成的直接生物量损失为3.2 t/a,总计损失约64万元;风电场建设将使东沙沙洲鸟类栖息地面积减少81.5 km2,约占总栖息地面积的13.9%,但风机对鸻鹬类等中小型涉禽、水鸟的觅食影响不大,风电场区域仍可作为这些鸟类的觅食地。在影响分析的基础上提出了设计、施工、运营阶段相应的防范措施。  相似文献   

17.
李磊  李艳红 《干旱环境监测》2013,(4):154-159,183
选取艾比湖流域1990年、2001年、2011年同期(9月)3期I.and.satTM遥感影像,基于归一化植被指数NDVI,提取植被覆盖等级图,利用ArcGIS9.3和Fragstas3.3对该流域植被景观的变化进行了分析研究。结果表明:1990—2011年,该流域植被覆盖度变化明显,低植被覆盖区和较低植被覆盖区都有所减少,分别由1990年的34.05%和32.94%减少到2011年的32.8%和24.06%;较高植被覆盖区和高植被覆盖区有所增加,分别由8.49%和5.20%增长到15.13%和9.83%,但水域面积退化明显,由1990年的525.9765km2缩小至494.9876km2,减少了30.9889km2,退缩幅度达O.4%;最大斑块指数(LPI)由17.04上升到21.10,香农多样性指数(SHDI)和香农均势度指数(SHEI)分别由1.5387和0.8588增长到1.6395和0.9150。表明艾比湖流域景观格局混杂程度愈来愈高,空间异质性在逐年加强,总体空间格局向破碎化趋势发展。  相似文献   

18.
利用多星遥感影像动态监测了2015年春季太湖北部湖湾沉水植被分布的变化过程,并对水生植被遥感监测中的几个关键问题展开了探讨。决策树方法获取的水生植被分布结果表明,2015年4月28日太湖北部湖湾发现明显沉水植被分布面积约11.2 km~2,与2014年同期相比,新出现的较大面积沉水植被分布区域主要集中在田鸡山西和锡东水厂附近。提出应及时清理打捞,避免水生植被死亡腐烂,威胁水质安全。  相似文献   

19.
This paper describes the impact of urbanization on the groundwater regime in a fast growing city, Solapur, in central India, giving special emphasis on the management of the present and ultimate demand of water in 2,020 AD. The objective is to apprise the city planners and administrators of the effects of urbanization on the groundwater regime in a fast growing medium-sized city in a developing country where the infrastructure developments are not in conformity with the rapid growth in population. Solapur city with an area of 178.57 km2 receives a recharge of about 24 million m3 of groundwater from various sources annually. Reduction in recharge, as conventionally assumed due to the impact of urbanization, could not, however, be well established. Instead, there was a rise in recharge as water use in the city grew from time to time and more and more water was supplied to satisfy the human needs. Compared to mid-1970s, groundwater levels have increased within the main city area due to increased recharge and decreased groundwater abstraction. However, outside the main city area, there is a general decline in groundwater levels due to increased groundwater utilization for irrigation purposes. Groundwater quality deterioration has been highly localized. Water quality has deteriorated during the last 10 years, especially in dugwells, mainly due to misuse and disuse of these structures and poor circulation of groundwater. However, in case of borewells, comparison of the present water quality with that in mid-1970s and early 1980s does not show any perceptible change. Deeper groundwater tapped by borewells can still be used for drinking purposes with caution.  相似文献   

20.
北京市某高层建筑高空电磁辐射环境影响分析   总被引:1,自引:0,他引:1  
选取北京市某代表性高层居民楼顶平台作为高空电磁辐射环境水平监测点进行综合场强和选频监测,评价总体电磁辐射环境水平,并分析监测区域电磁辐射能量的来源。结果表明:该高空监测区域的电磁辐射环境总体水平低于国家规定的公众照射导出限值,但高于地面水平。监测区域主要受30 km 外的中波台影响,其次是9 km 外的中央电视塔。影响最大的是639 kHz频率的中波信号,占100 kHz~300 MHz总场强的95%以上,其次是1.28 MHz频率的中波信号。提出,开展敏感建筑物规划建设时,应考虑中波的传播特性和对环境的影响。  相似文献   

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