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51.
基于GIS的上海市嘉定区暴雨积涝灾害风险区划研究 总被引:3,自引:0,他引:3
根据2006-2012年上海嘉定区9个气象站点的小时降水资料,结合嘉定区的社会经济与自然地理要素,构建一个集致灾因子、孕灾环境、承灾体及防灾减灾能力为一体的区域暴雨积涝风险评价模型。通过GIS技术实现各指标的栅格化,并利用指数模型对各因子基于500 m×500 m栅格的基本单元进行计算,编制嘉定区的暴雨积涝灾害风险区划图,构成嘉定区五个等级的风险,分别为高、次高、中等、次低和低。区划结果表明嘉定区的暴雨积涝灾害危险性指数从中心向外围成递减的趋势,且嘉定镇、新城和工业南区相对风险较高,华亭、徐行、南航和江桥风险相对较低。经嘉定区历年暴雨积涝灾情资料、典型暴雨积涝案例和专家的验证,均表明风险区划的结果和实际灾情符合度较高,对嘉定暴雨积涝的防灾减灾具有重要的现实指导意义。 相似文献
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1960年以来山西秋季连阴雨的气候特征分析 总被引:1,自引:0,他引:1
利用山西省66个测站1960-2009年秋季(9-11)月的逐日降水量,采用线性倾向估计、累积距平法、EOF及Morlct小波分析方法,系统地分析了山西秋季连阴雨的变化趋势和时空结构特征,建立了秋季连阴雨强度指数模型。结果表明:山西秋季年际区域性连阴雨次数和阴雨日数呈明显的线性减少趋势,过程雨量呈波动上升趋势,连阴雨次数的累积距平表现为"三升两降"型变化;山西秋季连阴雨的年际和年代际变化特征明显,1960-1970年代中期,有5~6年的周期变化,1990年代后期有2年的周期变化特征,年代际变化呈"波动状"变化规律;全省秋季连阴雨从南到北呈递减分布,除北部的天镇、山阴、繁峙等呈增加趋势外,各代表站表现为一致的减少趋势,南部、东南部及五台山为连阴雨多发区,大同盆地、忻州盆地、太原盆地为少发区;山西秋季连阴雨存在2~3年、8年左右的显著振荡周期。1970年代中期到1980年代中期,8年左右振荡周期的振幅最大,能量最强,是周期振荡最强的阶段。 相似文献
54.
Tao M Fengkui Duan Kebin He Yu Qin Dan Tong Guannan Geng Xuyan Liu Hui Li Shuo Yang Siqi Ye Beiyao Xu Qiang Zhang Yongliang Ma 《环境科学学报(英文版)》2019,31(9):8-20
With rapid economic growth and urbanization, the Yangtze River Delta(YRD) region in China has experienced serious air pollution challenges. In this study, we analyzed the air pollution characteristics and their relationship with emissions and meteorology in the YRD region during 2014–2016. In recent years, the concentrations of all air pollutants, except O_3,decreased. Spatially, the PM_(2.5), PM_(10), SO_2, and CO concentrations were higher in the northern YRD region, and NO_2 and O_3 were higher in the central YRD region. Based on the number of non-attainment days(i.e., days with air quality index greater than 100), PM_(2.5) was the largest contributor to air pollution in the YRD region, followed by O_3, PM_(10), and NO_2.However, particulate matter pollution has declined gradually, while O_3 pollution worsened.Meteorological conditions mainly influenced day-to-day variations in pollutant concentrations. PM_(2.5) concentration was inversely related to wind speed, while O_3 concentration was positively correlated with temperature and negatively correlated with relative humidity.The air quality improvement in recent years was mainly attributed to emission reductions.During 2014–2016, PM_(2.5), PM_(10), SO_2, NO_x, CO, NH_3, and volatile organic compound(VOC)emissions in the YRD region were reduced by 26.3%, 29.2%, 32.4%, 8.1%, 15.9%, 4.5%, and0.3%, respectively. Regional transport also contributed to the air pollution. During regional haze periods, pollutants from North China and East China aggravated the pollution in the YRD region. Our findings suggest that emission reduction and regional joint prevention and control helped to improve the air quality in the YRD region. 相似文献
55.
基于GIS的东辽河流域生态安全空间差异评价研究 总被引:6,自引:1,他引:5
生态安全建设是协调经济开发与生态保护的重要战略.区域生态安全评价与预警研究具有空间特性、非线性、随机性,研究过程中必须处理大量的空间信息,而空间分析和空间数据管理正是GIS的优势,它使各环境要素的分布态势及彼此间的拓扑关系一目了然,并且图文并茂地展示全流域的生态安全格局.在充分研究辽河流域生态环境状况基础上,选取东辽河流域11个县市区,借助GIS格网赋值技术,讨论了基于GIS的东辽河生态安全空间差异的评价方法.首先,拟定"压力-状态-响应"(P-S-R)指标体系,实地调查并收集资料;然后,数字化流域,运用模糊AHP法赋权并量化计算;最后,建立东辽河流域生态安全指数GRID数据库,进行GIS的空间Interpolate运算和Assembly分析.结果表明,公主岭市是生态安全区,约占全流域面积的10.78%;西丰市和东辽县是生态不安全区,约占流域面积的13.07%;其余8个地区为生态安全中等区,约占全流域面积的76.15%.评价结果与各地区现状生态环境评价基本-致.提出了相应的生态保护建议. 相似文献
56.
应用激光粒度粒形分析仪、灰熔融性测定仪、原子吸收光谱仪和XRD等仪器手段对国内2种垃圾焚烧飞灰的密度、颗粒特性、熔点、成分和晶相结构等物理化学性质进行了详细的研究。研究发现,2种灰样颗粒直径的数量积分分布非常接近,其中基本没有超过40 μm的颗粒。由于垃圾焚烧飞灰在化学成分上存在的差异导致了其熔点有很大的不同。此外,XRD结果显示不同来源的飞灰其晶相结构存在较大的差别,这可能与垃圾的来源和焚烧工艺以及烟气处理方法有关。实验结果为飞灰无害化低温烧结工艺的选择和运行参数的制定提供了依据。 相似文献
57.
Jie Liu Fan Chen Haiqing Geng Xinxin Qiu Binbin Cai 《Frontiers of Environmental Science & Engineering in China》2010,4(3):349-360
The major features of different road sections were identified. Methods quantitatively determining the ecological impact of
highway construction were discussed, and a demonstration was presented. The Dabao highway (from Dali to Baoshan) and the Sixiao
highway (from Simao to Xiaomengyang) passing through the Longitudinal Range-Gorge Region were used as examples in this paper.
For the normal road sections having no important species to protect, a method of ecosystem health assessment was introduced
to calculate the overall range of the ecological impact of highway construction. For the road sections having plants or soils
of interest, indexes were selected and the range of impact was determined using mathematical methods such as regression analysis
and variance analysis. The range of impact on animal populations was also discussed in terms of the minimum living areas required
by animal populations and the fragmentation caused by highway construction. The results indicate that the zones impacted by
highway construction were composed of both regular and anomalous figures, the range of impacts for different landforms of
the two sample highways were substantially different; highway construction had dramatic effects on roadside ecosystem health;
the impact on soil factors of farmland was greater than 200 m, and the distance may exceed 1000 m when important large animals
were considered. 相似文献
58.
Fang Li Jing Jin Dongqin Tan Longxing Wang Ningbo Geng Rong Cao Yuan Gao Jiping Chen 《环境科学学报(英文版)》2016,28(10):209-217
Hexabromocyclododecane(HBCD) and tetrabromobisphenol A(TBBPA) are two kinds of brominated flame retardants and widely present in the environment and biota. The levels,spatial distributions and mass inventories of HBCD and TBBPA were investigated in sediments and paddy soils from the Liaohe River Basin in northeast China. The concentrations of ΣHBCD and TBBPA were in the range of not detected(nd) to 4.02 ng/g dry weight(dw) and 0.03 to 4.06 ng/g dw, respectively. γ-HBCD was dominated in sediments,while the abundance of α-HBCD was relatively high in paddy soils. The spatial distributions of HBCD and TBBPA in surface sediments and paddy soils indicated that the local point-input was their major source. The significant correlation between total organic carbon(TOC) contents and the HBCD levels suggested that TOC content also exerted an influence on the distribution of HBCD in sediments. Meanwhile, it was found that the irrigation with river water was not the major transportation pathway of HBCD and TBBPA in paddy soils. Based on the study, it was estimated that there were about 1.67 tons HBCD and 2.20 tons TBBPA deposited into sediments of the Liaohe River system every year. The total mass inventories of HBCD and TBBPA in sediments were far higher than that in paddy soils. 相似文献
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