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Guanglin Ji Zhijiong Huang Xiao Tang Jiamin Ou Menghua Lu Yuanqian Xu Zhuangmin Zhong Qinge Sh Huangjian Wu Chuanzeng Zheng Tao Deng Duohong Chen Min He Junyu Zheng 《环境科学学报(英文版)》2022,34(4):233-248
The conventional Ensemble Kalman filter (EnKF), which is now widely used to calibrate emission inventories and to improve air quality simulations, is susceptible to simulation errors of meteorological inputs, making accurate updates of high temporal-resolution emission inventories challenging. In this study, we developed a novel meteorologically adjusted inversion method (MAEInv) based on the EnKF to improve daily emission estimations. The new method combines sensitivity analysis and bias correction to alleviate the inversion biases caused by errors of meteorological inputs. For demonstration, we used the MAEInv to inverse daily carbon monoxide (CO) emissions in the Pearl River Delta (PRD) region, China. In the case study, 60% of the total CO simulation biases were associated with sensitive meteorological inputs, which would lead to the overestimation of daily variations of posterior emissions. Using the new inversion method, daily variations of emissions shrank dramatically, with the percentage change decreased by 30%. Also, the total amount of posterior CO emissions estimated by the MAEInv decreased by 14%, indicating that posterior CO emissions might be overestimated using the conventional EnKF. Model evaluations using independent observations revealed that daily CO emissions estimated by MAEInv better reproduce the magnitude and temporal patterns of ambient CO concentration, with a higher correlation coefficient (R, +37.0%) and lower normalized mean bias (NMB, -17.9%). Since errors of meteorological inputs are major sources of simulation biases for both low-reactive and reactive pollutants, the MAEInv is also applicable to improve the daily emission inversions of reactive pollutants. 相似文献
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基于洞庭湖流域1993-2011年的自然、社会经济等资料系列,立足于致灾因子危险性、孕灾环境脆弱性的自然属性和承灾体易损性的社会属性两方面,建立指标体系,并在此基础上,运用GIS技术与数理统计相结合的方法,对该流域农业旱灾风险进行综合评价。结果表明:从整体上看,长沙市和湘潭市为农业旱灾高风险区,益阳市和衡阳市为较高风险区,岳阳市、邵阳市和怀化市为中等风险区,娄底市为较低风险区,株洲市、郴州市、永州市、常德市、张家界市和湘西自治州为低风险区。孕灾环境脆弱性、致灾因子危险性、承灾体易损性的差异是导致各地州市农业旱灾风险度大小的症结所在。 相似文献
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<正>森林乃维护自然界生态平衡、调节大气、净化环境的重要可持续资源。东南亚林业大国缅旬多年来在推动林木经济发展同时,尽力实对林业资源的可再生保护。迄今为止,该国已逐渐形成由现行《缅甸联邦森 相似文献
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Biogenic silica (BSi) contents in the marsh plants (Phragmites australis, Scirpus mariqueter and Spartina alterniflora) and associated
sediments in Chongming Island eastern intertidal flat of the Yangtze Estuary were determined. The BSi contents in P. australis, S.
mariqueter and S. alterniflora varied from 25.78–42.74 mg/g, 5.71–19.53 mg/g and 6.71–8.92 mg/g, respectively. Over the entire
growth season, P. australis and S. mariqueter were characterized by linear accumulation patterns of BSi. The aboveground biomass
(leaves and culms) of the marsh plants generally contained more BSi than underground biomass (roots). BSi contents were relatively
higher in dead plant tissues than in live tissues which was probably due to the decomposition and the leaching of labile components
of plant tissues such as organic carbon and nitrogen. Comparing with the habitats of S. mariqueter and S. alterniflora, the highest BSi
content was recorded in sediments inhabited by P. australis, with an annual average of 15.69 mg/g. Overall, the intertidal marshes in
the Yangtze Estuary may act as a net sink of BSi via plant uptake and sedimentary burial. 相似文献
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循环经济是一种以提高生态效率为核心、以遵循3R技术为原则、以两低一高为基本特征、符合可持续发展理念的经济增长模式.推行循环经济是实现社会-经济-环境系统可持续发展的必由之路.通过阐述循环经济内涵,并就长沙环境质量、资源供需情况、农业发展等方面作了分析,并且分析了长沙推行循环经济可能面临的问题,提出发展循环经济是长沙新的发展经济模式和实现经济、社会、环境协调发展的战略选择,并就此提出了建议. 相似文献