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811.
乌鲁木齐土壤中多环芳烃的污染特征及生态风险评价 总被引:3,自引:1,他引:2
在乌鲁木齐地区不同功能区采集28个表层土壤样品,对土壤中多环芳烃(PAHs)的污染特征进行研究,并运用正定矩阵因子分析法对其来源进行分析,采用苯并[a]芘的毒性当量浓度(TEQBa P)对PAHs的生态风险进行评价。研究显示,土壤中∑16 PAHs含量为331~15 799μg/kg,其平均值为(5 018±4 896)μg/kg(n=28),以3环、4环为主。∑16PAHs的浓度呈现出交通区工业区公园区农业区居民商业区的变化趋势;正定矩阵因子分析法表明,乌鲁木齐表层土壤中PAHs的主要来源及贡献分别为煤的燃烧(51.19%),汽油车燃烧(19.02%),柴油车燃烧(18.35%),机动车石油的泄漏(11.42%);53%的采样点TEQBa P值超过荷兰土壤标准目标参考值,主要集中在交通区和工业区。 相似文献
812.
乌鲁木齐市主要饮用水源地水质健康风险评价 总被引:3,自引:1,他引:2
运用美国环保局(USEPA)推荐的健康风险评价模型对2011—2013年乌鲁木齐市主要地下和地表饮用水源地水体中污染物通过饮水途径致人体健康危害风险进行初步评价,结果显示:致癌物和非致癌物所致个人健康危害年风险均低于USEPA和国际辐射防护委员会(ICRP)最大可接受风险水平,致癌物产生的健康危害年风险数量级10-9~10-5,高出非致癌物101~107数量级,各饮用水源地的个人健康危害年总风险以致癌物风险为主,致癌物中的重金属六价铬和砷风险占总风险的比例高达99.6%,应优先控制,地表水源地中挥发性有机致癌物对人体产生的潜在健康危害也不容忽视,非致癌物中要特别重视氟化物的危害。 相似文献
813.
在线单颗粒气溶胶质谱在大气重金属铅污染事故中的应用研究 总被引:2,自引:1,他引:1
重金属铅由于其对人体健康的影响而广受关注。利用在线单颗粒气溶胶质谱仪对2012年发生在华南地区的一次金属铅污染事故中的含铅颗粒物的质谱特征、粒径分布及排放规律进行了分析。监测发现A、B两个监测点位的含铅颗粒物比例多在夜间或凌晨达到高峰,高峰时刻含铅颗粒物数浓度占比最高可达67%,对比广州市区、鹤山超级站的含铅颗粒物浓度占比,可知该地区含铅颗粒物的污染程度较高。两监测点位的含铅颗粒物质谱特征及粒径分布情况非常相似,可能存在相同的排放源或具有相同的形成机制。质谱中都均含有明显的铅、元素碳、硫、硫酸盐等信号,可能来自于燃煤源的排放。通过进一步对比分析燃煤烟气排放的含铅颗粒物质谱特征,判断其为燃煤源排放。 相似文献
814.
815.
Subba Rao N 《Environmental monitoring and assessment》2008,136(1-3):437-447
Trace elements are essential for human health. However, excess concentrations of these elements cause health disorders. A
study has been carried out in Visakhapatnam environs, Andhra Pradesh, India to ascertain the causes for the origin and distribution
of iron content in the groundwaters. Fifty groundwater samples are collected and analyzed for iron. The content of iron ranges
from 400 to 780 μg/l. A comparison of groundwater data with rock and soil chemistry suggests that the concentration of iron
(400–530 μg/l) in the groundwaters is derived from the rocks and soils due to geogenic processes. This concentration is taken
as a natural occurrence of iron in the groundwaters of the study area for assessing the causes for its next higher content
(>530 μg/l). Relatively higher concentration of iron (540–550 μg/l) is observed at some well waters, where the wells are located
nearby municipal wastewaters, while the very high concentration of iron (610–780 μg/l) is observed in the industrially polluted
groundwater zones, indicating the impact of anthropogenic activities on the groundwater system. These activities mask the
concentration of iron caused by geogenic origin. Hence, both the geogenic and anthropogenic activities degrade the groundwater
quality. Drinking water standards indicate that the iron content in all the groundwater samples exceeds the permissible limit
(300 μg/l) recommended for drinking purpose, causing the health disorders. Necessity of close monitoring of groundwater quality
for assessing the impact of geogenic and anthropogenic sources with reference to land use/land cover activities is emphasized
in the present study area to protect the groundwater resources from the pollution. 相似文献
816.
Perrino C Canepari S Cardarelli E Catrambone M Sargolini T 《Environmental monitoring and assessment》2008,136(1-3):69-86
A field study was carried out at six locations in the Lazio region (Central Italy) aimed at characterising atmospheric particulate
matter (PM10 and PM2.5) from the point of view of the chemical composition and grain size distribution of the particles, the mixing properties of
the atmosphere, the frequency and relevance of natural events. The combination of four different analytical techniques (ion
chromatography, X-ray fluorescence and ICP for inorganic components, thermo-optical analysis for carbon compounds) yielded
sound results in terms of characterisation of the air masses. During the first three months of the study (October–December
2004), many pollution events of natural (sea-salt or desert dust episodes) or anthropogenic nature were identified and characterised.
More than 90% of the collected mass was identified by chemical analysis. The central role played by the mixing properties
of the lower atmosphere when pollution events occurred was highlighted. The results show a major impact of primary anthropogenic
pollutants on traffic stations and a homogeneous distribution of secondary pollutants over the regional area. An evaluation
of the sources of PM and an identification of possible reliable tracers were obtained using a chemical fractionation procedure. 相似文献
817.
根据全国饮用水源地调查和现行政策法规,结合江苏省及泰州市饮用水源地专项整治情况,全面分析了饮用水源地防控和预警工作中存在的问题,借鉴国外饮用水源地防控预警的特色做法,阐述了适合中国国情的饮用水源防控及预警的10项保护措施,供环保从业人员参考。 相似文献
818.
819.
820.
Global warming impacts the water cycle not only by changing regional precipitation levels and temporal variability, but also by affecting water flows and soil moisture dynamics. In Brandenburg, increasing average annual temperature and decreasing precipitation in summer have already been observed. For this study, past trends and future effects of climate change on soil moisture dynamics in Brandenburg were investigated, considering regional and specific spatial impacts. Special Areas of Conservation (SACs) were focused on in particular. A decreasing trend in soil water content was shown for the past by analyzing simulation results from 1951 to 2003 using the integrated ecohydrological model SWIM [Krysanova, V., Müller-Wohlfeil, D.-I., Becker, A., 1998. Development and test of a spatially distributed hydrological/water quality model for mesoscale watersheds. Ecol. Model. 106, 261–289]. The trend was statistically significant for some areas, but not for the entire region. Simulated soil water content was particularly low in the extremely dry year 2003. Comparisons of simulated trends in soil moisture dynamics with trends in the average annual Palmer Drought Severity Index for the region showed largely congruent patterns, though the modeled soil moisture trends are characterized by a much higher spatial resolution. Regionally downscaled climate change projections representing the range between wetter and drier realizations were used to evaluate future trends of available soil water. A further decrease of average available soil water ranging from −4% to −15% was projected for all climate realizations up to the middle of the 21st century. An average decrease of more than 25 mm was simulated for 34% of the total area in the dry realization. Available soil water contents in SACs were generally higher and trends in soil moisture dynamics were lower mainly due to their favorable edaphic conditions. Stronger absolute and relative changes in the simulated trends for the past and future were shown for SACs within Brandenburg than for the state as a whole, indicating a high level of risk for many wetland areas. Nonetheless, soil water content in SACs is expected to remain higher than average under climate change conditions as well, and SACs therefore have an important buffer function under the projected climate change. They are thus essential for local climate and water regulation and their status as protected areas in Brandenburg should be preserved. 相似文献