Huaihe River Basin(HRB) is located in China’s north-south climatic transition zone,which is very sensitive to global climate change.Based on the daily maximum temperature,minimum temperature,and precipitation data of...Huaihe River Basin(HRB) is located in China’s north-south climatic transition zone,which is very sensitive to global climate change.Based on the daily maximum temperature,minimum temperature,and precipitation data of 40 meteorological stations and nine monthly large-scale ocean-atmospheric circulation indices data during 1959–2019,we present an assessment of the spatial and temporal variations of extreme temperature and precipitation events in the HRB using nine extreme climate indices,and analyze the teleconnection relationship between extreme climate indices and large-scale ocean-atmospheric circulation indices.The results show that warm extreme indices show a significant(P < 0.05) increasing trend,while cold extreme indices(except for cold spell duration) and diurnal temperature range(DTR) show a significant decreasing trend.Furthermore,all extreme temperature indices show significant mutations during 1959-2019.Spatially,a stronger warming trend occurs in eastern HRB than western HRB,while maximum 5-d precipitation(Rx5day) and rainstorm days(R25) show an increasing trend in the southern,central,and northwestern regions of HRB.Arctic oscillation(AO),Atlantic multidecadal oscillation(AMO),and East Atlantic/Western Russia(EA/WR) have a stronger correlation with extreme climate indices compared to other circulation indices.AO and AMO(EA/WR) exhibit a significant(P < 0.05) negative(positive)correlation with frost days and diurnal temperature range.Extreme warm events are strongly correlated with the variability of AMO and EA/WR in most parts of HRB,while extreme cold events are closely related to the variability of AO and AMO in eastern HRB.In contrast,AMO,AO,and EA/WR show limited impacts on extreme precipitation events in most parts of HRB.展开更多
海水入侵是全球性环境地质问题,对沿海城市的供水安全及生态环境造成严重威胁。微生物对环境变化具有高度的敏感性,近年来许多学者开始关注微生物对海水入侵的响应特征,为海水入侵调查研究提供了新的思路与方法。为了充分认识该领域的...海水入侵是全球性环境地质问题,对沿海城市的供水安全及生态环境造成严重威胁。微生物对环境变化具有高度的敏感性,近年来许多学者开始关注微生物对海水入侵的响应特征,为海水入侵调查研究提供了新的思路与方法。为了充分认识该领域的研究进展,基于Web of Science核心数据库,利用文献计量学可视化分析方法对海水入侵微生物响应特征研究现状、热点及趋势进行分析。文献分析结果表明:该新兴研究领域的成果集中出现在2011年以后,发文量和引文量呈现上升趋势;中国积极参与海水入侵微生物响应特征研究,其发文量及高引用指数均位居世界第二位,研究成果具有较高的学术影响力;由关键词聚类分析可知,该领域热门研究方向包括地下水微生物群落对海水入侵的响应研究、土壤微生物群落对海水入侵的响应研究、元素地球化学循环与微生物作用研究。研究结果表明:咸-淡水交互区微生物群落演替受盐度、溶解氧、温度、有机碳、pH值等多种因子的共同影响,其主控因子随水文地质条件的不同而变化;海水入侵会影响微生物介导的碳、氮、硫、铁等物质循环过程;在含水层中发现的典型海洋细菌及嗜盐古菌对海水入侵的识别具有重要指示意义,相关技术是海水入侵传统调查方法的有力补充,在古海水入侵、现代海水入侵的辨别应用中具有较大优势和潜力。展开更多
Daihai Lake, a modern lacustrine rift basin, located in Inner Mongolia, North China, serves as an important modern analog for understanding deltaic depositional processes in an active rift setting. Two of the deltas ...Daihai Lake, a modern lacustrine rift basin, located in Inner Mongolia, North China, serves as an important modern analog for understanding deltaic depositional processes in an active rift setting. Two of the deltas （Yuanzigou delta and Bulianghe delta） on the margins of Daihai Lake were surveyed to compare and contrast stacking patterns using aerial photographs, field trenching and sediment sampling. Shallow cores and trench data collected from the margins of Daihai Lake indicate that a variety of depositional processes have been active since Daihai Lake formed. Two 3-D sedimentation models which employ chronostratigraphic correlation technique were generated. The chronostratigraphic sedimentation models predict and represent the architectures and sand-body continuity of sediments. Stratigraphical coincidence of the broad sheeted drifts and channel erosion suggests a coupling between downslope and alongslope processes. Distributary mouth bars are prevalent in the front of deltas on steeper slopes due to the dominance of down-slope flows. On the contrary, the along-slope currents favor the development of distal bar deposits with sheeted sandbodies on gentle depositional slopes. This study provides an insight into the architecture of complex sedimentary facies associated with highlighting key differences between downslope flows and alongslope currents. The distribution of sand within these deltas is of particular interests, with applications in understanding the architecture of hydrocarbon reservoirs formed in lacustrine rift basin.展开更多
基金Under the auspices of National Natural Science Foundation of China(No.52279016,51909106,51879108,42002247,41471160)Natural Science Foundation of Guangdong Province,China(No.2020A1515011038,2020A1515111054)+1 种基金Special Fund for Science and Technology Development in 2016 of Department of Science and Technology of Guangdong Province,China(No.2016A020223007)the Project of Jinan Science and Technology Bureau(No.2021GXRC070)。
文摘Huaihe River Basin(HRB) is located in China’s north-south climatic transition zone,which is very sensitive to global climate change.Based on the daily maximum temperature,minimum temperature,and precipitation data of 40 meteorological stations and nine monthly large-scale ocean-atmospheric circulation indices data during 1959–2019,we present an assessment of the spatial and temporal variations of extreme temperature and precipitation events in the HRB using nine extreme climate indices,and analyze the teleconnection relationship between extreme climate indices and large-scale ocean-atmospheric circulation indices.The results show that warm extreme indices show a significant(P < 0.05) increasing trend,while cold extreme indices(except for cold spell duration) and diurnal temperature range(DTR) show a significant decreasing trend.Furthermore,all extreme temperature indices show significant mutations during 1959-2019.Spatially,a stronger warming trend occurs in eastern HRB than western HRB,while maximum 5-d precipitation(Rx5day) and rainstorm days(R25) show an increasing trend in the southern,central,and northwestern regions of HRB.Arctic oscillation(AO),Atlantic multidecadal oscillation(AMO),and East Atlantic/Western Russia(EA/WR) have a stronger correlation with extreme climate indices compared to other circulation indices.AO and AMO(EA/WR) exhibit a significant(P < 0.05) negative(positive)correlation with frost days and diurnal temperature range.Extreme warm events are strongly correlated with the variability of AMO and EA/WR in most parts of HRB,while extreme cold events are closely related to the variability of AO and AMO in eastern HRB.In contrast,AMO,AO,and EA/WR show limited impacts on extreme precipitation events in most parts of HRB.
文摘海水入侵是全球性环境地质问题,对沿海城市的供水安全及生态环境造成严重威胁。微生物对环境变化具有高度的敏感性,近年来许多学者开始关注微生物对海水入侵的响应特征,为海水入侵调查研究提供了新的思路与方法。为了充分认识该领域的研究进展,基于Web of Science核心数据库,利用文献计量学可视化分析方法对海水入侵微生物响应特征研究现状、热点及趋势进行分析。文献分析结果表明:该新兴研究领域的成果集中出现在2011年以后,发文量和引文量呈现上升趋势;中国积极参与海水入侵微生物响应特征研究,其发文量及高引用指数均位居世界第二位,研究成果具有较高的学术影响力;由关键词聚类分析可知,该领域热门研究方向包括地下水微生物群落对海水入侵的响应研究、土壤微生物群落对海水入侵的响应研究、元素地球化学循环与微生物作用研究。研究结果表明:咸-淡水交互区微生物群落演替受盐度、溶解氧、温度、有机碳、pH值等多种因子的共同影响,其主控因子随水文地质条件的不同而变化;海水入侵会影响微生物介导的碳、氮、硫、铁等物质循环过程;在含水层中发现的典型海洋细菌及嗜盐古菌对海水入侵的识别具有重要指示意义,相关技术是海水入侵传统调查方法的有力补充,在古海水入侵、现代海水入侵的辨别应用中具有较大优势和潜力。
基金supported by the Chinese National Natural Science Fund Project(41072084)National Program on Key Basic Research Project(973 Program)(No. 2009CB219502-3)Prof.Qiu Yinan at RIPED(Research Institute for Petroleum Exploration and Development) of CNPC(China National Petroleum Corporation) for his belief in this work and financial support of the research
文摘Daihai Lake, a modern lacustrine rift basin, located in Inner Mongolia, North China, serves as an important modern analog for understanding deltaic depositional processes in an active rift setting. Two of the deltas （Yuanzigou delta and Bulianghe delta） on the margins of Daihai Lake were surveyed to compare and contrast stacking patterns using aerial photographs, field trenching and sediment sampling. Shallow cores and trench data collected from the margins of Daihai Lake indicate that a variety of depositional processes have been active since Daihai Lake formed. Two 3-D sedimentation models which employ chronostratigraphic correlation technique were generated. The chronostratigraphic sedimentation models predict and represent the architectures and sand-body continuity of sediments. Stratigraphical coincidence of the broad sheeted drifts and channel erosion suggests a coupling between downslope and alongslope processes. Distributary mouth bars are prevalent in the front of deltas on steeper slopes due to the dominance of down-slope flows. On the contrary, the along-slope currents favor the development of distal bar deposits with sheeted sandbodies on gentle depositional slopes. This study provides an insight into the architecture of complex sedimentary facies associated with highlighting key differences between downslope flows and alongslope currents. The distribution of sand within these deltas is of particular interests, with applications in understanding the architecture of hydrocarbon reservoirs formed in lacustrine rift basin.
