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981.
河南省1950~1990年水旱灾害分析   总被引:6,自引:1,他引:6  
蒋金才  季新菊 《灾害学》1996,11(4):69-73
根据河南省各县1950~1990年水、旱灾史料,进行系统的整理分析,揭示了本省各流域水、旱灾害农业损失程度,论述了水、旱灾的成灾原因、特点和规律。并对水、旱灾的灾度作了初步的探析。  相似文献   
982.
区域水资源承载能力综合评价:主成分分析法的应用   总被引:115,自引:1,他引:115  
针对模糊综合评判法在综合评价中存在的主观随意性问题,提出采用主成分分析法进行区域水资源承载能力综合评价。首先对各区域的灌溉率、水资源利用率、水资源开发程度、供水模数、需水模数、人均供水量和生态环境用水率这七个主要因素进行了分析;然后,根据主成分分析法的原理,运用少数几个新的综合指标对原来的七个指标所包含的信息进行最佳综合与简化,研究其在各区域水资源开发利用过程中的不同贡献及综合效应;同时,以评价参  相似文献   
983.
厌氧氨氧化(Anammox)是一种高效低耗的新型生物脱氮技术,在城市污水处理中具有广阔的应用前景.在城市污水脱氮系统中,厌氧氨氧化菌(AnAOB)是否存在、丰度如何及Anammox脱氮效能如何,是进行Anammox评估的重要指标.本研究重点介绍了在生物脱氮系统中进行AnAOB菌种测定和菌群结构分析的分子生物学技术及Anammox脱氮贡献率的计算方法 .结果发现,对于AnAOB的菌种测定和菌群结构分析,可采用实时荧光定量聚合酶链锁反应(qPCR)、16S rRNA高通量测序和宏基因组测序等分子生物学技术;Anammox脱氮贡献率可通过物料衡算法和15N同位素示踪法计算.同时,对这些评估方法存在的一些局限性也进行了阐述.总体而言,如何科学、有效、全面地评估Anammox在生物脱氮系统中发挥的作用仍是一个需要长期探究的课题.但随着相关研究的不断深入,检测手段和分析方法也会得到不断优化,这将为Anammox工艺的理论研究及工程应用提供重要支持.  相似文献   
984.
Understanding atmospheric mercury (Hg) accumulation in remote montane forests is critical to assess the Hg ecological risk to wildlife and human health. To quantify impacts of vegetation, climatic and topographic factors on Hg accumulation in montane forests, we assessed the Hg distribution and stoichiometric relations among Hg, carbon (C), and nitrogen (N) in four forest types along the elevation of Mt. Gongga. Our results show that Hg concentration in plant tissues follows the descending order of litter > leaf, bark > root > branch > bole wood, indicating the importance of atmospheric Hg uptake by foliage for Hg accumulation in plants. The foliar Hg/C (from 237.0 ± 171.4 to 56.8 ± 27.7 µg/kg) and Hg/N (from 7.5 ± 3.9 to 2.5 ± 1.2 mg/kg) both decrease along the elevation. These elevation gradients are caused by the heterogeneity of vegetation uptake of atmospheric Hg and the variation of atmospheric Hg° concentrations at different altitudes. Organic soil Hg accumulation is controlled by forest types, topographic and climatic factors, with the highest concentration in the mixed forest (244.9 ± 55.7 µg/kg) and the lowest value in the alpine forest (151.9 ± 44.5 µg/kg). Further analysis suggests that soil Hg is positively correlated to C (r2 = 0.66) and N (r2 = 0.57), and Hg/C and Hg/N both increase with the soil depth. These stoichiometric relations highlight the combined effects from environmental and climatic factors which mediating legacy Hg accumulation and selective Hg absorption during processes of organic soil mineralization.  相似文献   
985.
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   
986.
Ji  Ying  Du  Jianhui  Wu  Xiaoqing  Wu  Zhong  Qu  Deqiang  Yang  Dan 《Environment, Development and Sustainability》2021,23(9):13731-13754
Environment, Development and Sustainability - Cold chain logistics has become one of the main sources of carbon emissions. Meanwhile, the implementation of low-carbon economy has become an...  相似文献   
987.
Environmental Science and Pollution Research - Co3O4 is a promising Hg0 removal catalyst for industrial application. Operating temperature and low sulfur resistance are two of the main problems...  相似文献   
988.
Chen  Zhen  Yu  Chuan  Lan  Shenyu  Liu  Yifan  Li  Cunjun  Chen  Xianlei  Klemeš  Jiří Jaromír  Zhu  Mingshan 《Environmental Chemistry Letters》2023,21(5):2475-2481
Environmental Chemistry Letters - The growing energy demand in the context of climate change issues requires the development of green fuels such as hydrogen from water. Piezocatalytic water...  相似文献   
989.
This paper reviews the utilisation of waste as an alternative fuel, commonly referred to as Waste-to-Energy (WTE). The paper contains a comprehensive survey of the literature published in this field with comparative analysis of different approaches and methods. The main features and properties of municipal and industrial waste have been analysed as these can vary significantly from location to location and year to year. The paper discusses the applicability and limitations of current and developing WTE technologies as well as new and emerging WTE technologies and the recent developments in design of for producing heat, power and fuels. Methodologies that are considered include criteria for technology selection, together with procedures that comply with the environmental EC regulations Best Available and Best Applicable Techniques (BREFs).  相似文献   
990.
Environmental Science and Pollution Research - Achieving the carbon neutrality in China has great impact on alleviating global warming. Compost application, an important measure to promote soil...  相似文献   
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