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881.
Acharee Kaewlaoyoong Chi Thanh Vu Chitsan Lin Chien Sen Liao Jenq-Renn Chen 《Environmental Earth Sciences》2018,77(12):457
The increasing usage and disposal of plastic products could cause the wide distribution of phthalate esters (PAEs) in various environmental media. In this study, six PAE compounds, namely dimethyl phthalate, diethyl phthalate, di-n-butyl phthalate, benzyl butyl phthalate, di(2-ethylhexyl) phthalate (DEHP), di-n-octyl phthalate, were analyzed in various samples collected from the major plastic industrial area of southern Taiwan, including soil, fertilizer and plastic products, for the purposes of identifying of the possible sources of PAEs and assessing the related health risk. The results show that PAEs in soil samples was dominated by DEHP, with the total concentrations in the range of 0.7?±?0.5, 0.2?±?0.1, and 0.3?±?0.2 mg kg?1 for soil samples from farmland, household back gardens and the roadside, respectively. Contents of PAEs in chemical fertilizer (ND—0 0.87 mg kg?1) were higher than that in organic fertilizer (ND—0.08 mg kg?1), and PAEs concentrations (ND—316 mg kg?1) in plastic mulching films were much less than those in the other types of plastic products (ND—1719 mg kg?1), implying that major sources of PAEs in agricultural soil could be the use of chemical fertilizer and plastic products other than plastic mulching films. Health risk assessment suggested that, via the exposure to PAEs in soil, the potential non-cancer and carcinogenic risks for adults and children are minimal in most cases, except that a “moderate” carcinogenic risk for children exposure to DEHP. The results of this study can serve as a reference for further pollution prevention and environmental protection plans in relation to the industrial operation and discharge as well as the farming practices. 相似文献
882.
After a heavy and continuous rainfall from July 27 to 28, 1981, geological disasters involving large debris flow affected the northern part of Wafangdian City and Pulandian City in Dalian, northeast China, and caused considerable loss of life and property. In recent years, precipitation has continued to increase significantly in Dalian, where the largest debris flow gully, named the Dongmatuncun main ditch, is situated. The Dongmatuncun main ditch is 2 km away from the north side of the right bank of the Fudu River in Wanjialing, Wafangdian City. The geomorphological and hydrological conditions, combined with the characteristics of the debris flow solid source, are conducive to debris flow development. Moreover, with an increase in rainfall, debris flow recurrence becomes increasingly likely. We study the debris flow gully in Dongmatun Village by analyzing the formation conditions through field survey. Fuzzy comprehensive evaluation and analytic hierarchy process are used to evaluate the risk of debris flow. Results indicate that the debris flow gully in Dongmatun Village is highly dangerous and debris flow occurs during heavy rainfall. In addition, the breakout of debris flow can threaten human life and property. 相似文献
883.
Climatic effects of air pollutants over china: A review 总被引:3,自引:0,他引:3
Tropospheric ozone(O3) and aerosols are major air pollutants in the atmosphere. They have also made significant contributions to radiative forcing of climate since preindustrial times. With its rapid economic development, concentrations of air pollutants are relatively high in China; hence, quantifying the role of air pollutants in China in regional climate change is especially important. This review summarizes existing knowledge with regard to impacts of air pollutants on climate change in China and defines critical gaps needed to reduce the associated uncertainties. Measured monthly, seasonal, and annual mean surface-layer concentrations of O3 and aerosols over China are compiled in this work, with the aim to show the magnitude of concentrations of O3 and aerosols over China and to provide datasets for evaluation of model results in future studies. Ground-based and satellite measurements of O3 column burden and aerosol optical properties, as well as model estimates of radiative forcing by tropospheric O3 and aerosols are summarized. We also review regional and global modeling studies that have investigated climate change driven by tropospheric O3and/or aerosols in China; the predicted sign and magnitude of the responses in temperature and precipitation to O3/aerosol forcings are presented. Based on this review, key priorities for future research on the climatic effects of air pollutants in China are highlighted. 相似文献
884.
885.
Wang Yian Liu Donglie Dong Jie Zhang Lu Guo Jincheng Liao Mingsheng Gong Jianya 《Landslides》2021,18(7):2609-2619
Landslides - SAR Interferometry (InSAR) has been proven to be effective for measuring landslides deformation. However, the InSAR application of landslide mapping is limited by the blind observation... 相似文献
886.
云膏共生组合是受化学沉积分异作用控制而形成的岩石组合,对其沉积序列精细刻画,有利于揭示诸多蒸发环境下的沉积学信息。依据鄂尔多斯盆地中部奥陶系马家沟组五段6(简称“马五6亚段”)亚段钻井、岩心资料,开展了岩石宏观和微观观察、典型沉积序列刻画等工作。研究结果表明: (1)鄂尔多斯盆地中部马五6亚段普遍发育碳酸盐岩与蒸发岩共生组合,主要由10种岩石类型构成;(2)主要发育5种沉积序列,下云上膏的岩性组合和序列顶部多发育暴露面等特征表明单个序列具有向上变浅、变咸的演化特征,是蒸发台地叠合海水渐次补给作用的结果;(3)在局限—蒸发台地环境下,主要发育潟湖/滩间海、颗粒滩、灰泥丘、台坪4种沉积亚相及11种沉积微相,与经典的蒸发潮坪序列在岩性组合与沉积构造方面存在明显的差异;(4)马五6亚段沉积期发育2次海平面升降,沉积环境可分别对应于云(膏)质潟湖—灰泥丘/颗粒滩—膏质潟湖—蒸干膏质潟湖和灰泥丘/颗粒滩—膏质潟湖—蒸干膏质潟湖—台坪。该研究结果可为鄂尔多斯盆地马五6亚段沉积环境与海平面变化研究提供系统的岩石学证据。 相似文献
887.
888.
本文依据南沙海域实际地震测线资料,相关证据显示早中新世(T60-T40之间)南沙腹地多盆地发生挤压反转构造,南沙西南部多见挤压褶皱。南沙海域及周边地区在早中新世开始发生全区的挤压隆升和剥蚀,经过局部剥蚀量和构造抬升量定量估算,认为隆升核心区域的九章盆地由于挤压隆升导致的地层剥蚀量大于3 500 m。"早中新世挤压隆升幕"形成一个以郑和隆起为核心的"碟形"剥蚀区,活动时间与西南次海盆的扩张时间一致,西南次海盆的扩张可能是造成隆升幕的重要原因。由于隆升剥蚀前存在深埋,南沙腹地(九章盆地为代表)和南沙北缘(中业、永登盆地为代表)的"浅、薄、小"盆地群的价值不容忽视。 相似文献
889.
以12.5 m 数字高程模型数据为基础,采用数字地貌分析方法提取了濑溪河流域的高程剖面和面积-高程积分(HI)等地貌参数,分析了2021年9月16日四川盆地东南部泸县MS6.0地震震中附近区域地貌与构造活动的响应关系。结果显示:震中西侧的螺观山和梯子崖背斜在震中的南北两端存在明显的缩短量差异;HI条带状低值区的展布方向与流域内构造的方向一致,HI高值区位于华蓥山两条断裂夹持的谷地,但在震中附近存在WNW向的HI低值带。综合分析认为,泸县地震震中附近应存在一走向为WNW的隐伏构造,它不仅调节了螺观山和梯子崖背斜在震中南北两端的缩短量差异,也使得HI值受其影响呈低值特征,该结果与震源机制解结果、等震线长轴走向以及余震空间展布的优势方向相一致。 相似文献
890.
Natural Hazards - In addition to its inherent evolution trend, landslide displacement contains strong fluctuation and randomness, and omni-directional landslide displacement prediction is more... 相似文献