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91.
为探究中国第十四届运动会(简称“十四运”)期间西安大气PM2.5中水溶性无机离子浓度水平及来源,利用高分辨率MARGA ADI 2080离子在线分析仪对西安“十四运”前、“十四运”期间和“十四运”后水溶性无机离子进行实时观测,分析了不同时段水溶性无机离子组分污染特征、pH变化及污染来源。结果表明,“十四运”前、“十四运”期间和“十四运”后PM2.5质量浓度分别为13.4、11.9、32.6μg/m3,SNA(NO-3、SO42-和NH+4三者统称)质量浓度分别为5.8、5.4、13.3μg/m3,占总水溶性无机离子的91.6%~93.6%。“十四运”前和“十四运”期间NO-3与SO42-质量浓度比分别为0.7和0.9,表明移动源的比例增加,主要受交通管控的影响。“十四运”后NO 相似文献
92.
随着经济的快速发展,人们逐步意识到依靠不断增加生产要素投入的粗放型经济发展模式已难以为继,绿色发展遂成为全球共识。作为北京生态涵养区的京北地区,在冬奥会和京津冀协同发展的机遇下,制定绿色发展战略,保护生态涵养功能,加快产业转型升级,促进经济、社会、环境协调发展,具有十分重要的意义。本文归纳总结了国际上绿色发展的借鉴经验,通过对京北地区经济发展现状和绿色发展SWOT的分析,设计出京北地区绿色发展基本框架,包括一个目标、三大战略、五项重点任务和五项保障措施。通过落实经济系统、社会系统和环境系统的三大战略措施,突破资源环境约束和共享绿色经济,最终实现京北地区的绿色跨越式发展。 相似文献
93.
94.
Thais Q. Morcatty Jonathan C. Bausch Macedo K. Anne-Isola Nekaris Qingyong Ni Carlos C. Durigan Magdalena S. Svensson Vincent Nijman 《Conservation biology》2020,34(6):1525-1535
Seizures of hundreds of jaguar heads and canines in Central and South America from 2014 to 2018 resulted in worldwide media coverage suggesting that wildlife traffickers are trading jaguar body parts as substitutes for tiger parts to satisfy the demand for traditional Asian medicine. We compiled a data set of >1000 seized wild cats (jaguar [Panthera onca], puma [Puma concolor], and ocelot [Leopardus pardalis]) from 19 Central and South American countries and China. We ran generalized additive mixed models to detect trends in wild-cat seizures from 2012 to 2018 and assess the effects of socioeconomic factors of source countries and between those countries and China on the number of wild cats seized. Jaguar seizures increased over time, and most of the seized jaguar pieces were canines (1991 of 2117). Around 34% (32 of 93) of the jaguar-part seizure reports were linked with China, and these seizures contained 14-fold more individuals than those intended for domestic markets. Source countries with relatively high levels of corruption and Chinese private investment and low income per capita had 10–50 times more jaguar seizures than the remaining sampled countries. The number of Chinese residents in Central and South America was not significantly related to the number of jaguars seized. No socioeconomic factors influenced the seizures of puma and ocelots. Legal market chains may provide structure for the illegal chain; thus, the influx of illegal jaguar products is potentially a side effect of the economic partnership between Central and South American countries and China. Poverty and high levels of corruption in the source countries may motivate local people to engage in illegal activities and contribute to the growth of this trade. Supply-side interventions to curb this threat to Neotropical wild cats may include improved training for officials and promotion of governance and the value of protecting these animals to local people. 相似文献
95.
2010年广州亚运期间空气质量与污染气象条件分析 总被引:9,自引:2,他引:7
利用2010年11月4日~12月10日广州地区NO2、O3、SO2、PM、能见度实测资料,区域空气污染指数RAQI及大气输送扩散特征参数,分析广州亚运期间空气质量与气象条件变化特征.结果表明,亚运期间空气质量比亚运前后好,能见度比亚运前后大,PM1和PM2.5浓度比亚运前后小,能见度与PM1和PM2.5有较好的反相关;亚运期间NO2和SO2日均值和小时均值均达到国家一级标准,PM10日均值和O3小时均值均满足国家二级标准,污染物得到较好的控制;广州地区SO2受本地源和外地源远距离输送叠加影响,NO2受本地源影响较大;广州周边城市NO2、SO2和PM10有向广州输送的潜势,而广州O3有向其周边城市扩散的潜势;亚运期间污染气象条件比亚运前后有利,亚运期间污染物浓度降低得益于政府实施的减排措施及良好的气象条件. 相似文献
96.
Cell concentration, viability and culture composition of airborne bacteria during a dust event in Beijing 总被引:1,自引:0,他引:1
Hongli Yuan Daizhou Zhang Yanning Shi Baozhen Li Jinshui Yang Xuejian Yu Nan Chen Makiko Kakikawa 《环境科学学报(英文版)》2017,29(5):33-40
Airborne bacteria were measured when a dust storm passed Beijing in spring 2012 with a focus on cell concentration,viability and TSA-and R2A-cultured strain composition.The concentration varied at an order of 10~7 cells/m~3 with dust loading(demonstrated with PM_(10))and they had a very close correlation(R_T~2 = 0.91,p 0.01).At the time of highest PM_(10) of652 μg/m~3,the bacterial concentration reached 1.4 × 10~8 cells/m~3,which was larger than that before and after the dust event by one order.Bacterial viability,the ratio of number concentration of viable cells to total cells,was 32%-64%and smaller in the dust plume than that before the dust arrival.Bacterial strains from the culture ranged between 2.5 x 104 and4.6×10~5 CFU/m~3 and no correlation with PM_(10) was determined.Their composition was different before and after the dust arrival according to 16SrRNA gene sequences and strains belong to Actinomycetes and Firmicutes were the majority in the dust samples. 相似文献
97.
Multi-temporal satellite imagery from the Moderate Resolution Imaging Spectrometer (MODIS) was used to map the different ecosystems of Southeast Asian (SEA) rice paddies. The algorithm was based on temporal profiles of vegetation strength and/or water content, using MODIS surface reflectance in visible to near-IR range. The results obtained from the analysis were compared to national statistics. Estimated SEA regional rice area was 42 × 106 ha, which agrees with published values. The model performance was dependent on rice ecosystems. Good linear relationships between the model results and the national statistics were observed for rainfed rice. High linear coefficients of determination, R2, were also found for irrigated rice and upland rice, but the model tended to underestimate irrigated rice and overestimate upland rice. However, these high R2 values indicated that the model effectively simulated spatial distribution of these rice areas. These R2 values were either of similar magnitude or larger than those reported in literature, regardless of the rice ecosystem. Poor correlation was observed for deepwater rice. 相似文献
98.
An important research area in life sciences is devoted to modeling, prediction, and dynamics of gene-expression patterns.
As clearly understood in these days, this enterprise cannot become satisfactory without acknowledging the role of the environment.
To a representation of past, present, and most likely future states, we also encounter measurement errors and uncertainties.
This paper surveys and improves recent advances in understanding the foundations and interdisciplinary implications of the
newly introduced gene–environment networks, and it integrates the important theme of carbon dioxide emission reduction into
the networks and dynamics. We also introduce some operational and managerial issues of practical working and decision making,
expressed in terms of sliding windows, quadrants (modules) of parametric effects, and navigating (controlling) between such effects and directing them. Given data from DNA microarray experiments and environmental records, we extract
nonlinear ordinary differential equations that contain parameters that have to be determined. For this, we employ modern (Chebychevian)
approximation and (generalized semi-infinite) optimization. After this is provided, time- discretized dynamical systems are
studied. A combinatorial algorithm with polyhedra sequences allows to detect the region of parametric stability. Finally,
we analyze the topological landscape of gene–environment networks with its structural (in)stability. By embedding as a module
and investigating CO2 emission control and figuring out game theoretical aspects, we conclude. This pioneering work is theoretically elaborated,
practically devoted to health care, medicine, education, living conditions, and environmental protection, and it invites the
readers to future research.
相似文献
99.
The impact of long-range transport of yellow sand from Asian Continent to the Taipei Metropolitan Area (Taipei) not only deteriorates
air quality but also poses health risks to all, especially the children and the elderly. As such, it is important to assess
the enhancement of PM10 during yellow sand periods. In order to estimate PM10 enhancement, we adopted factor analysis to distinguish the yellow-sand (YS) periods from non-yellow-sand (NYS) periods based
on air quality monitoring records. Eight YS events were identified using factor analysis coupling with an independent validation
procedure by checking background site values, examining meteorological conditions, and modeling air mass trajectory from January
2001 to May 2001. The duration of each event varied from 11 to 132 h, which was identified from the time when the PM10 level was high, and the CO and NO
x
levels were low. Subsequently, we used the artificial neural network (ANN) to simulate local PM10 levels from related parameters including local gas pollutants and meteorological factors during the NYS periods. The PM10 enhancement during the YS periods is then calculated by subtracting the simulated PM10 from the observed PM10 levels. Based on our calculations, the PM10 enhancement in the maximum hour of each event ranged from 51 to 82%. Moreover, in the eight events identified in 2001, it
was estimated that a total amount of 7,210 tons of PM10 were transported by yellow sand to Taipei. Thus, in this study, we demonstrate that an integration of factor analysis with
ANN model could provide a very useful method in identifying YS periods and in determining PM10 enhancement caused by yellow sand. 相似文献
100.
为了研究2008年北京奥运会前期污染物浓度变化特征,对北京气象塔3层高度上的大气污染物(NO2和O3)进行加强观测,分析其变化特征。观测结果表明,由于北京奥运会前期采取了严格的空气质量控制措施,NO2浓度相对车辆限行前下降了45.3%,且随着高度递增逐渐降低;O3浓度最大值和日均值有所降低,其最大值出现时间较10年前提前了12 h,且有4 h左右处于相对平稳状态。O3浓度峰值主要是受NO2的控制,O3浓度峰值出现时间提前反映出北京大气氧化效率不断提高。对于观测期间出现光化学污染事件,利用同期气象资料和大气污染监测数据分析,发现造成这次大气污染的主要原因是气象因子:地面多处于弱高压场控制中,大气层结稳定,风力较弱(小于2 m/s),并伴随着连续高温、强辐射和低湿。 相似文献