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81.
《China Geology》2022,5(3):402-410
This study investigated water samples collected from the surface water and groundwater in Wuhan City, Hubei Province, China in different stages of the outbreak of the coronavirus disease 2019 (hereinafter referred to as COVID-19) in the city, aiming to determine the distribution characteristics of antiviral drugs in the city’s waters. The results are as follows. The main hydrochemical type of surface water and groundwater in Wuhan was Ca-HCO3. The major chemical components in the groundwater had higher concentrations and spatial variability than those in the surface water. Two antiviral drugs and two glucocorticoids were detected in the surface water, groundwater, and sewage during the COVID-19 outbreak. Among them, chloroquine phosphate and cortisone had higher detection rates of 32.26% and 25.80%, respectively in all samples. The concentrations of residual drugs in East Lake were higher than those in other waters. The main drug detected in the waters in the later stage of the COVID-19 outbreak in Wuhan was chloroquine phosphate, whose detection rates in the surface water and the groundwater were 53.85% and 28.57%, respectively. Moreover, the detection rate and concentration of chloroquine phosphate were higher in East Lake than in Huangjia Lake. The groundwater containing chloroquine phosphate was mainly distributed along the river areas where the groundwater was highly vulnerable. The residual drugs in the surface water and the groundwater had lower concentrations in the late stage of the COVID-19 outbreak than in the middle of the outbreak, and they have not yet caused any negative impacts on the ecological environment.©2022 China Geology Editorial Office.  相似文献   
82.
《China Geology》2022,5(3):411-420
A large number of antibiotics have been discharged into rivers by human activities, posing a threat to aquatic ecosystems. The surface water of the Yellow River Basin also suffers antibiotic pollution, which hinders the improvement in the aquatic ecological environment. This study investigated and analyzed the characteristics and assessed the ecological risks of antibiotic pollution in surface water bodies such as canals, rivers and fish ponds in Kaifeng, Henan Province, which is a key city along the lower reaches of the Yellow River. The test results are as follows. A total of 15 types of antibiotics were detected in the surface water. They had a total antibiotic concentration of 12.2–249.9 μg/L, of which tetracyclines (TCs) and quinolones accounted for the highest percentages. Six types of quinolones had detection rates of up to 100%, and doxycycline (DC) and oxytetracycline (OTC) had average concentrations of 29.52 μg/L1 and 13.71 μg/L, respectively. The major canals with water diverted from the Yellow River had total concentrations of quinolones and TCs of 22. 0 μg/L and 14.9 μg/L, respectively, which were higher than those in previous studies. This phenomenon may be related to the decrease in the water flow of the Yellow River during the dry season and the increase in the antibiotic consumption of residents in the context of the Covid-19 outbreak. The upper reaches of the Huiji River in the Xiangfu District had higher antibiotic content than other districts in Kaifeng. Specifically, TCs accounted for 72.38%–91.84% of all antibiotics, and the DC and OTC concentrations were significantly higher than other antibiotics in the upper reaches. As indicated by the ecological risk assessment results, TCs had the highest ecological risks to green algae. Among them, DC had medium-high risks; TC, OTC, and chlortetracycline (CTC) had medium-high risks; trimethoprim (TMP) and lomefloxacin (LOM) had low risks; other TC antibiotics had no risk. Compared with green algae, most antibiotics showed higher ecological risks to daphnia and lower ecological risks to fish. DC and OTC dominate antibiotic pollutants in the surface water in Kaifeng City, and especially in Xiangfu District, where DC and OTC have medium-high risks. The TCs in the major Yellow River showed medium risks to both green algae and daphnia. It can be speculated that the antibiotic pollution in the Yellow River might pose a certain threat to the ecological security of water in Kaifeng City.©2022 China Geology Editorial Office.  相似文献   
83.
作为全球性危机,新冠疫情和气候危机在影响范围、效果、原因等方面的相似之处可能使两种危机的效果叠加,而二者的不同之处又可能导致应对政策的相互干扰,带来更加严峻的复合风险。文中全面分析了全球面临的新冠疫情和气候危机的复合风险,识别了新冠疫情对全球气候变化适应进程的影响,以及适应在各国疫后绿色复苏计划中的地位。研究表明,目前全球的绿色复苏中较少考虑适应,而绿色复苏为同时恢复经济和增强气候恢复力提供了机会,如果能在绿色复苏中考虑变革性适应,将显著提升社会经济系统对气候变化等冲击的抵御能力与恢复力,实现疫情后更持续和更有韧性的经济发展。  相似文献   
84.
NASA's Deep Space 1 mission flew by Comet 19P/Borrelly on September 22, 2001.We present observations of molecular species obtained with the 30-m telescope of theInstitut de Radioastronomie Millimétrique (IRAM) and the Nançay radio telescopeat and near the time of this flyby. OH, HCN, and CS production rates were measured,while upper limits were deduced for CO, H2CO and H2S.  相似文献   
85.
This article focuses on the water distribution network in Paris, from the 1830s, when most Parisians got their water from public fountains and private wells, to the 1930s, by which time almost all of the capital’s inhabitants had been connected to the same network and enjoyed a standard service. It contributes, by a detailed analysis of the entire chain of mediators and mediation, to specify how the modern infrastructure ideal actually took form. In that aim, we analyze the manner in which each actor (public as well as private), in accordance with his/her constraints and resources, which depend on his/her position in the social space, was able to conceive of his/her environment, define objectives, confront problems, make choices and deploy a whole range of frequently innovative practices. In order to understand the underlying factors, our task consists in identifying the actors, modi operandi, progress and phases involved in universalizing water services. Spatially analyzing the extension of the water network, this article demonstrates that the process of universalization, far from being the inexorable and linear outcome of the action of a small number of “major historical forces”, was the upshot of the actions of a whole range of actors acting in specific different geographical, social, economic and technical contexts. The achievement of the “modern infrastructural ideal” as a macro-social phenomenon was ultimately down to a long accumulation process of a multitude of actions, interactions, conflicts and learning processes.  相似文献   
86.
The Finite Pool of Worry (FPW) hypothesis states that humans have finite emotional resources for worry, so that when we become more worried about one threat, worry about other threats decreases. Despite its relevance, no conclusive empirical evidence for the hypothesis exists. We leverage the sudden onset of new worries introduced by the COVID-19 pandemic as a natural experiment to test the FPW hypothesis and a related hypothesis, the Finite Pool of Attention (FPA) hypothesis. The FPA hypothesis proposes that when we pay more attention to one threat, our attention to other threats decreases. To test these two hypotheses, we assessed self-reported attention, self-reported worries, and Twitter/news attention to various threats (climate change, terrorism, economic problems, and others) throughout the pandemic in three countries (USA, Italy, and China). We find that as attention to and worry about COVID-19 increases, attention to climate change decreases, but worry does not. Our results are confirmed by further analysis of a large, longitudinal U.S. sample. We find that public perceptions that COVID-19 and climate change are related do not fully explain the positive relationship in worry between the two hazards. In summary, our findings suggest that while there may be a Finite Pool of Attention to threats, there is limited evidence for a Finite Pool of Worry.  相似文献   
87.
新冠肺炎(COVID-19)疫情给农户生计发展带来了重大风险,而生计资本是抵御疫情冲击、阻断返贫危机的关键。论文以重点疫区湖北省及周边地区为研究区域,基于可持续生计分析框架,从生计资本“结构—存量”多维视角出发,采用内生转换回归模型分析疫区465户农户生计资本对疫情风险的抵御作用。研究发现:① 重点疫区农户生计资本总量不高,疫情可能诱发生计脆弱性但不是唯一要素,基层公共卫生建设也极为重要;② 生计资本对疫情风险有显著抵御效应,人力资本维度作用更为凸显,物质资本占比过高反而会削弱疫情应对能力;③ 农户生计资本结构与存量分布不均,家庭劳动力、健康投入、财富积累、居住环境、社会阅历等是核心要素;④ 疫后生计恢复主要依赖于人力与金融资本的积累,而帮扶关键在于应急和兜底保障,要根据区域农户生计特征拟定差异化的疫情常态防控举措。  相似文献   
88.
89.
李涛  李宇  戴靓  王姣娥 《地理研究》2021,40(11):3225-3241
科学评估重大公共卫生事件扰动对节假日城际出行活动的影响对于科学预防疫情传播、提升城际出行安全性具有重要意义。文章利用百度迁徙平台提供的城际出行数据,系统探讨了COVID-19疫情影响下的“五一”小长假城际出行规模时序变化、格局变化与出行流格局特征,并基于空间计量模型剖析了疫情与节假日叠加背景下的城际出行影响因素。结果表明:受COVID-19疫情影响,2020年“五一”小长假期间的城际出行规模同比下降达46.0%,时段波动主要表现为省内波动,省外城际出行总体较为平稳;COVID-19疫情对城际出行的影响呈现出东北>东中部>西部的特征;COVID-19疫情显著降低了“五一”小长假城际出行范围,相较于正常期70%的城际出行联系集中在400km范围内,疫情影响下的70%的城际出行联系集中在250 km范围以内;GDP、城镇化率、行政等级等城市规模吸引力因素,公路密度与高铁等交通变量是影响“五一”期间城际出行的主要因素,但各变量对城际出行的影响在“五一”不同时段具有时间异质性。公路密度与有无高铁具有显著的正向作用;城镇化率在出行期与返程期对城际出行分别起到了显著负向与正向作用;旅游资源丰富度仅在出行期显著。  相似文献   
90.
利用武汉市人口迁出规模指数与武汉迁入到湖北各市人口比例的乘积(MSI)及市内交通强度(TI),建立时间回归模型,分析各市的COVID-19每日新增病例;利用交通可达性及各市GDP比例,建立空间回归模型,分析湖北省各市COVID-19的万人累计感染率。结果显示:1)基于人口迁徙数据与各市每日新增COVID-19病例构建的回归模型具有显著性(Sig.=0.00),R2达0.715;从标准化系数结果可以看出,MSI(0.85)对各市每日新增病例的影响程度更高;2)累计万人感染率与医疗机构数、GDP具有显著的正相关关系,与床位数量不相关;3)基于交通路网、社会经济数据与湖北省各市的万人累计感染率构建的空间回归模型亦具有显著性,其标准化决定系数为0.672,各市GDP比例对模型的影响更大。  相似文献   
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