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集中式饮用水水源地水质预警指标体系构建 总被引:3,自引:2,他引:1
饮用水水源地水质预警是建立健全饮用水安全保障体系的关键环节,构建水源地水质预警指标体系是水源地监控预警工作的重要基础。系统分析了常规水质在线、生物毒性在线、卫星遥感、人工巡视等水质预警监测技术手段,并分析比较了各方法的优缺点。以此为基础,遵循水源地预警指标体系构建原则与实际需求,统筹兼顾,提出了建立以常规理化-生物毒性在线监测相结合,遥感监测与人工巡查相统筹的一体化水源地水质预警指标体系,为水源地水质预警监控工作提供合理的、科学的技术支撑。 相似文献
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为进一步推进疫情防控应急管理规划理论和相关制度的改进完善,采用国外先进作战任务规划方法探讨面向重大疫情的应急管理规划问题,从理论和实践相结合的角度论述面向疫情的应急防控管理规划基本任务、主要类型、规划业务要求、任务规划成果;提出疫情防控应急管理规划流程,并设计预先规划、应急规划和临机调控规划3种典型规划,构建覆盖国家、省、市县和乡镇/街道4个层级的疫情防控应急管理规划体系。结果表明:基于作战任务规划的应急管理规划流程和体系科学性更强、适用性更高,对应急管理规划、应急预案与防疫预案的制定有参考价值。 相似文献
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To improve the desulfurization efficiency of sorbents at low cost, modified semi-coke was used as the substrate for mixed metal oxides (ZFM; oxides of zinc [Zn], iron [Fe], and manganese [Mn]) in hot gas desulfurization. Performance of the prepared ZFM/modified semi-coke (MS) sorbents were evaluated in a fixed-bed reactor in the temperature range 400-550°C. Results showed that the molar ratio of Mn to Zn, effect of the substrate, the calcination temperature, and the sulfidation temperature influenced the performance of the sorbents. Optimum conditions for the preparation of the ZFM/MS sorbents were molar ratio of Mn(NO(3))(2)·6H(2)O, Zn(NO(3))(2), and Fe(NO(3))(3), 0.6:1:2; mass ratio of ZFM0.6 to modified semi-coke support, 1:1; and calcination temperature, 600°C. The ZFM0.6/MS sorbent thus prepared exhibited the best sorption sulfur capacity of 27.46% at 450°C. 相似文献
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The process of a bioindication of genotoxic effects of complex mixtures on the environment using higher plants is very appropriate and effective. We present the results of an in situ indication of the genotoxic effects of polluted environment near Žilina city. For a more complex monitoring we used: the Tradescantia micronucleus (Trad-MCN) assay, the Tradescantia microspore test and an evaluation of the abortivity of the pollen grains of native plant species. We found significant differences in the frequency of the micronuclei when using the Trad-MCN test in local of Dubeň. The Tradescantia pollen abortivity test showed significant differences in the frequency of the abortive pollen grains between the exposed groups and the control group. By using native plant species in the pollen abortivity test we found significant differences in both of the two locations for the four following species during two consecutive years: Artemisia vulgaris, Melilotus albus, Trifolium pratense, Typha latifolia. 相似文献
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Journal of Material Cycles and Waste Management - Foot and mouth disease and avian influenza are highly contagious. The foot and mouth disease virus can be transmitted in a number of ways,... 相似文献
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Xiaoli Shen Sheng Li William J. McShea Dajun Wang Jianping Yu Xiaogang Shi Wei Dong Xiangcheng Mi Keping Ma 《Conservation biology》2020,34(1):158-167
Flagship species have been used widely as umbrella species (i.e., species with large home range whose protection often provides protection for sympatric species) in the management of China's nature reserves. This conflation of flagship and umbrella species is best represented by the giant panda (Ailuropoda melanoleuca) and other large, endangered mammals designated as conservation targets in site selection and planning of reserves. Few empirical studies have tested the effectiveness of flagship species as surrogates for a broader range of sympatric species. Using extensive camera-trap data, we examined the effectiveness of management zones designated to protect flagship (target) species in conserving sympatric species in 4 wildlife reserves (Gutianshan, Changqing, Laohegou, and Wolong). We tested whether the progression from peripheral to core zones was associated with an increasing habitat association for both target and sympatric species. The distribution patterns of the study species across the zones in each reserve indicated a disparity between management zones and the species’ habitat requirements. Management zone was included in the final model for all target species, and most of them had higher occurrence in core zones relative to less-protected zones, but zone was not a predictor for most of the sympatric species. When management zone was associated with the occurrence of sympatric species, threatened species generally had higher detections in core zones, whereas common species had higher detections outside of the core zone. Our results suggested that reserve planning based on flagship species does not adequately protect sympatric species due to their specialized habitat requirements. We recommend re-examining the effectiveness of management zoning and urge a multispecies and reserve-wide monitoring plan to improve protection of China's wildlife. 相似文献
310.
北京市2018年春季一次沙尘回流过程的污染特征 总被引:1,自引:0,他引:1
通过监测数据分析,结合轨迹模拟和特征雷达图的分析结果,对2018年4月14~19日北京出现的一次沙尘天气过程进行分析.结果显示:依据ρ(PM2.5)和ρ(PM10)及其比值PM2.5/PM10[ρ(PM2.5)/ρ(PM10),下同]的变化情况,此次沙尘过程可分为沙尘期、中间期、回流期和回流后期4个典型时期.沙尘期ρ(PM10)平均值达到(278.5±83.7)μg/m3,明显高于回流期和回流后期,回流后期ρ(PM2.5)平均值达到(135.5±16.9)μg/m3,明显高于回流期和沙尘期.沙尘期逐小时PM2.5/PM10<0.2,回流期和回流后期PM2.5/PM10比值分别介于0.3~0.6和0.5~0.8范围内.SO42-、NO3-和NH4+等(SNA)水溶性离子沙尘期浓度占比仅为7.3%±2.5%,沙尘回流期和回流后期SNA占比分别增长至47.0%±6.3%和51.3%±5.7%.研究表明,受天气系统影响,回流沙尘可裹挟南部的细颗粒和气态污染物输送到北京后发生累积和二次转化,从而推高PM2.5浓度,因此发生沙尘回流时,区域内应加强一次污染物排放的管控力度,同时北京市需进一步加强机动车氮氧化物的排放监管. 相似文献