Marine sedimentary strata are widely distributed in the coastal zone of the study area, and are rich in brine resources. The exploitation of underground water resources often first caused the intrusion of salt water i...Marine sedimentary strata are widely distributed in the coastal zone of the study area, and are rich in brine resources. The exploitation of underground water resources often first caused the intrusion of salt water in the marine strata. Based on the analysis of sea-salt water intrusion feature, the sea-salt water intrusion is divided into four stages: The occurrence and development stage(1976–1985), the rapid development stage(1986–1990), the slow development stage(1990–2000) and the stable development stage(2000–2015). Based on the comparative analysis of the relationship between seawater intrusion and influencing factors, this paper presents that the groundwater exploitation and the brine resources mining are the main control factors of sea-salt water intrusion. On this basis, we have established a numerical model of the sea-salt water intrusion. Using this model, we predicted the development trend of the sea-salt water intrusion. The results show that if the current development of groundwater and brine is maintained, the sea-salt water intrusion will gradually withdraw; once development of brine stops, sea-salt water will invade again. This provides the scientific basis for the rational exploitation of groundwater and the prevention of sea-salt water intrusion.展开更多
Aerosol samples were collected on board the research vessel Xuelong duringthe Fifteenth Chinese Antarctic Research Expedition (CHINARE XV) in November 1998—April 1999 andthe First Chinese Arctic Research Expedition i...Aerosol samples were collected on board the research vessel Xuelong duringthe Fifteenth Chinese Antarctic Research Expedition (CHINARE XV) in November 1998—April 1999 andthe First Chinese Arctic Research Expedition in July—September 1999.The areas traversed by theexpeditionary cruises include the Arctic Ocean, the western North Pacific Ocean and the easternIndian Ocean, covering 75°N—69°S and 75°E—133°W. Aerosol samples were also taken at theChinese Zhongshan Station in East Antarctica during the CHINARE XV. Analysis of the samples yieldedconcentrations of non-sea-salt sulfate and other soluble chemical species in the marine boundarylayer. The data suggest that the chemical composition of the marine aerosols is influenced by threemajor sources: continental air masses, primary oceanic emissions, and secondary marine aerosolsoriginated from oceanic emissions.The results show that, awing to strong anthropogenic sulfuremissions from the Asian continent, non-sea-salt sulfate concentrations in the Northern Hemisphere(the western North Pacific) marine aerosol are significantly higher than those in the SouthernHemisphere (the eastern Indian Ocean). Aerosol non-sea-salt sulfate concentrations appear to beinversely correlated with aerosol non-sea-salt chloride which shows significantly negative values,indicating the loss of chloride by sea salts, in most aerosol samples. Since gaseous HCl may beinvolved in chemical reactions that deplete atmospheric ozone in the marine boundary layer (MBL),high levels of acidic non-sea-salt-sulfate released by human activities in the low and mid-latitudesof the Northern Hemisphere may become an important potential contributor to the loss of atmosphericozone in the MBL.展开更多
We investigate the effects of sea-salt aerosol(SSA) activated as cloud condensation nuclei on the microphysical processes, precipitation, and thermodynamics of a tropical cyclone(TC). The Weather Research and Forecast...We investigate the effects of sea-salt aerosol(SSA) activated as cloud condensation nuclei on the microphysical processes, precipitation, and thermodynamics of a tropical cyclone(TC). The Weather Research and Forecasting model coupled with Chemistry(WRF-Chem) was used together with a parameterization of SSA production. Three simulations, with different levels of SSA emission(CTL, LOW, HIGH), were conducted. The simulation results show that SSA contributes to the processes of autoconversion of cloud water and accretion of cloud water by rain,thereby promoting rain formation. The latent heat release increases with SSA emission, slightly increasing horizontal wind speeds of the TC. The presence of SSA also regulates the thermodynamic structure and precipitation of the TC.In the HIGH simulation, higher latent heat release gives rise to stronger updrafts in the TC eyewall area, leading to enhanced precipitation. In the LOW simulation, due to decreased latent heat release, the temperature in the TC eye is lower, enhancing the downdrafts in the region; and because of conservation of mass, updrafts in the eyewall also strengthen slightly; as a result, precipitation in the LOW experiment is a little higher than that in the CTL experiment.Overall, the relationship between the precipitation rate and SSA emission is nonlinear.展开更多
Atmospheric circulation reconstruction based on glaciochemical records requires knowledge of chemical concentration controls, such as source, transport pathway and strength. To gain insight into these processes, the r...Atmospheric circulation reconstruction based on glaciochemical records requires knowledge of chemical concentration controls, such as source, transport pathway and strength. To gain insight into these processes, the relationships between glaciochemical records from two Northern Hemisphere sites (Mt. Logan in Yukon Territory and 20D in southern Greenland) and instrumental sea level pressure (SLP) series are investigated. Calibrations between Mt. Logan sea-salt sodium (ssNa+) concentration and SLP series show that ssNa+ concentrations are closely correlated with the autumntime (SON) Aleutian Low and the summertime (JJA) North Pacific Subtropical High. Both the deepened Aleutian Low and enhanced North Pacific Sub- tropical High strengthen the transport of sea-salt aerosols from the North Pacific to the Mt. Logan region. Calibrations between 20D ssNa+ concentrations and SLP series indicate that ssNa+ concentrations are closely related to the wintertime (Jan.) Icelandic Low. A deepening of the Icelandic Low strengthens winter storms and frequent cyclogenesis over the North Atlantic and pushes more sea-salt laden air masses to the Greenland ice sheet. Therefore, ice core ssNa+ records from the Mt. Logan region can be considered as a proxy for reconstructing the au- tumntime Aleutian Low and summertime North Pacific Subtropical High, and the ssNa+ records from Greenland ice core (20D) may provide a proxy for reconstructing the wintertime Icelandic Low.展开更多
The Gelsari and Lentini marshes, in east-central Sicily, are wetland under heavy anthropogenic pressure. This area is regularly subjected to water withdrawals and agriculture is practiced. Periodic bird census activit...The Gelsari and Lentini marshes, in east-central Sicily, are wetland under heavy anthropogenic pressure. This area is regularly subjected to water withdrawals and agriculture is practiced. Periodic bird census activities had been conducted in this area between 2016 and 2022 with collected data being supplemented with the data from a previous survey conducted between 2010 and 2016. During the censuses, numerous photographs were collected, which were later used for counts. In total, 121 surveys were carried out, with visits occurring approximately 20 times per year, covering all seasons. The data collected, both from bibliography and unpublished observations, were organised in table. 120 species and subspecies have been reported, 41 of which are in Annex I of the Birds Directive. Between 2021 and 2022, a water column measurement was taken in a central area of the Lentini marsh and compared with rainfall data in the area. It was found that water removal, occurring in both marshes in different modes, produced different effects on habitat conservation. Of the two marshes, Lentini is the one in which the existing favorable conditions in its most depressed areas, located below sea level, have allowed for the adequate conservation of the wetland. This environmental improvement having occurred with respect to the previous period has restored to the marsh its historically recognized possibility of not drying up completely during the summer period, allowing permanence of numerous birds. The obtained results suggest total elimination of agriculture and discontinuation of water withdrawals in the Lentini marsh as well as regulation of withdrawals in the Gelsari marsh.展开更多
Morphological changes with decreasing relative humidity(RH) of supersaturated sea-salt aerosol droplets on a quartz substrate were observed using a high-speed video-camera.Stable gypsum(CaSO4·2H2O) or the metasta...Morphological changes with decreasing relative humidity(RH) of supersaturated sea-salt aerosol droplets on a quartz substrate were observed using a high-speed video-camera.Stable gypsum(CaSO4·2H2O) or the metastable hemihydrate(CaSO4·0.5H2O) were precipitated as the RH decreased.The dynamic process of crystal growth under steady-state humidity was studied by controlling the RH;the metastable hemihydrate was precipitated at 70.5%-77.1% RH,and the apparent crystal growth rate was between 1.42 and 2.33 μm3/s.Stable gypsum was formed at 80.7%-82.2% RH,and the apparent crystal growth rate was between 0.70 and 0.81 μm3/s.展开更多
基金supported by Geological prospecting project in Shandong Province([2011]14)
文摘Marine sedimentary strata are widely distributed in the coastal zone of the study area, and are rich in brine resources. The exploitation of underground water resources often first caused the intrusion of salt water in the marine strata. Based on the analysis of sea-salt water intrusion feature, the sea-salt water intrusion is divided into four stages: The occurrence and development stage(1976–1985), the rapid development stage(1986–1990), the slow development stage(1990–2000) and the stable development stage(2000–2015). Based on the comparative analysis of the relationship between seawater intrusion and influencing factors, this paper presents that the groundwater exploitation and the brine resources mining are the main control factors of sea-salt water intrusion. On this basis, we have established a numerical model of the sea-salt water intrusion. Using this model, we predicted the development trend of the sea-salt water intrusion. The results show that if the current development of groundwater and brine is maintained, the sea-salt water intrusion will gradually withdraw; once development of brine stops, sea-salt water will invade again. This provides the scientific basis for the rational exploitation of groundwater and the prevention of sea-salt water intrusion.
基金supported by the National Natural Science Foundation of China under contract No.40306001the Foundation for the Author of National Excellent Doctoral Dissertation of China under contract No.200354)from the Ministry of Education and the Chinese Academy of Sciences+1 种基金supported by the Wang kuancheng Foundation(the Chinese Academy of Sciences)Fieldwork was sup-ported by the Chinese Arctic and Antarctic Adminis-tration(CAAA),the 15 th Chinese Antarctic Research Expedition and the First and Second Chinese Arctic Research Expedition.
文摘Aerosol samples were collected on board the research vessel Xuelong duringthe Fifteenth Chinese Antarctic Research Expedition (CHINARE XV) in November 1998—April 1999 andthe First Chinese Arctic Research Expedition in July—September 1999.The areas traversed by theexpeditionary cruises include the Arctic Ocean, the western North Pacific Ocean and the easternIndian Ocean, covering 75°N—69°S and 75°E—133°W. Aerosol samples were also taken at theChinese Zhongshan Station in East Antarctica during the CHINARE XV. Analysis of the samples yieldedconcentrations of non-sea-salt sulfate and other soluble chemical species in the marine boundarylayer. The data suggest that the chemical composition of the marine aerosols is influenced by threemajor sources: continental air masses, primary oceanic emissions, and secondary marine aerosolsoriginated from oceanic emissions.The results show that, awing to strong anthropogenic sulfuremissions from the Asian continent, non-sea-salt sulfate concentrations in the Northern Hemisphere(the western North Pacific) marine aerosol are significantly higher than those in the SouthernHemisphere (the eastern Indian Ocean). Aerosol non-sea-salt sulfate concentrations appear to beinversely correlated with aerosol non-sea-salt chloride which shows significantly negative values,indicating the loss of chloride by sea salts, in most aerosol samples. Since gaseous HCl may beinvolved in chemical reactions that deplete atmospheric ozone in the marine boundary layer (MBL),high levels of acidic non-sea-salt-sulfate released by human activities in the low and mid-latitudesof the Northern Hemisphere may become an important potential contributor to the loss of atmosphericozone in the MBL.
基金Supported by the National Natural Science Foundation of China(41875168 and 41705117)Natural Science Foundation of Guangdong Province(2015A030311026)Guangzhou Science and Technology Plan(201707010088)
文摘We investigate the effects of sea-salt aerosol(SSA) activated as cloud condensation nuclei on the microphysical processes, precipitation, and thermodynamics of a tropical cyclone(TC). The Weather Research and Forecasting model coupled with Chemistry(WRF-Chem) was used together with a parameterization of SSA production. Three simulations, with different levels of SSA emission(CTL, LOW, HIGH), were conducted. The simulation results show that SSA contributes to the processes of autoconversion of cloud water and accretion of cloud water by rain,thereby promoting rain formation. The latent heat release increases with SSA emission, slightly increasing horizontal wind speeds of the TC. The presence of SSA also regulates the thermodynamic structure and precipitation of the TC.In the HIGH simulation, higher latent heat release gives rise to stronger updrafts in the TC eyewall area, leading to enhanced precipitation. In the LOW simulation, due to decreased latent heat release, the temperature in the TC eye is lower, enhancing the downdrafts in the region; and because of conservation of mass, updrafts in the eyewall also strengthen slightly; as a result, precipitation in the LOW experiment is a little higher than that in the CTL experiment.Overall, the relationship between the precipitation rate and SSA emission is nonlinear.
基金supported by the Nati onal Natural Science Foundation of China(Distinguis lbed Innovat ion Group,40071 025)Chinese Academy of Sci ences(Grant Nos.Talent Project KZCX1-10-09,KZCX3-SW-33 9)+5 种基金Diector Fund of Key Laboratory of Ice Core and Cold Regions Fnvironment,Cold and Arid Regions Environmental and Engineeni ng Research Institute,CASThe First Chinese National Arctic R es earch ExpeditionUS Nat ional Science Founda tion(ATM-0139481,ESE-9904069)the Electric Power Research Ins titutethe US Environmental Protection Agency,and Environment Canadasupport from the Arctic Institute of North America,University of Calgary,and S.Whitlow,M.Spencer and C.Buck for analyzing samples from both cores.
文摘Atmospheric circulation reconstruction based on glaciochemical records requires knowledge of chemical concentration controls, such as source, transport pathway and strength. To gain insight into these processes, the relationships between glaciochemical records from two Northern Hemisphere sites (Mt. Logan in Yukon Territory and 20D in southern Greenland) and instrumental sea level pressure (SLP) series are investigated. Calibrations between Mt. Logan sea-salt sodium (ssNa+) concentration and SLP series show that ssNa+ concentrations are closely correlated with the autumntime (SON) Aleutian Low and the summertime (JJA) North Pacific Subtropical High. Both the deepened Aleutian Low and enhanced North Pacific Sub- tropical High strengthen the transport of sea-salt aerosols from the North Pacific to the Mt. Logan region. Calibrations between 20D ssNa+ concentrations and SLP series indicate that ssNa+ concentrations are closely related to the wintertime (Jan.) Icelandic Low. A deepening of the Icelandic Low strengthens winter storms and frequent cyclogenesis over the North Atlantic and pushes more sea-salt laden air masses to the Greenland ice sheet. Therefore, ice core ssNa+ records from the Mt. Logan region can be considered as a proxy for reconstructing the au- tumntime Aleutian Low and summertime North Pacific Subtropical High, and the ssNa+ records from Greenland ice core (20D) may provide a proxy for reconstructing the wintertime Icelandic Low.
基金国家重点基金课题:“环渤海滨海地球关键带地质结构和岩相古地理研究(42293261)”中国地质调查局项目:“津冀沿海资源环境承载力调查(DD20189506)”+2 种基金中国地质调查局项目:“黄渤海海岸带重点生态保护修复区综合地质调查(DD20211301)”自然科学基金项目:“渤海湾全新世海面标志点研究与变化历史重建(41372173)”“渤海湾西北岸4 ka BP前后古环境重建(41806109)”。
文摘The Gelsari and Lentini marshes, in east-central Sicily, are wetland under heavy anthropogenic pressure. This area is regularly subjected to water withdrawals and agriculture is practiced. Periodic bird census activities had been conducted in this area between 2016 and 2022 with collected data being supplemented with the data from a previous survey conducted between 2010 and 2016. During the censuses, numerous photographs were collected, which were later used for counts. In total, 121 surveys were carried out, with visits occurring approximately 20 times per year, covering all seasons. The data collected, both from bibliography and unpublished observations, were organised in table. 120 species and subspecies have been reported, 41 of which are in Annex I of the Birds Directive. Between 2021 and 2022, a water column measurement was taken in a central area of the Lentini marsh and compared with rainfall data in the area. It was found that water removal, occurring in both marshes in different modes, produced different effects on habitat conservation. Of the two marshes, Lentini is the one in which the existing favorable conditions in its most depressed areas, located below sea level, have allowed for the adequate conservation of the wetland. This environmental improvement having occurred with respect to the previous period has restored to the marsh its historically recognized possibility of not drying up completely during the summer period, allowing permanence of numerous birds. The obtained results suggest total elimination of agriculture and discontinuation of water withdrawals in the Lentini marsh as well as regulation of withdrawals in the Gelsari marsh.
基金supported by the National Natural Science Foundation of China (20933001,41175119 and 20873006)the National Basic Research Program of China (2009CB220100)the Trans-Century Training Program Foundation for the Talents
文摘Morphological changes with decreasing relative humidity(RH) of supersaturated sea-salt aerosol droplets on a quartz substrate were observed using a high-speed video-camera.Stable gypsum(CaSO4·2H2O) or the metastable hemihydrate(CaSO4·0.5H2O) were precipitated as the RH decreased.The dynamic process of crystal growth under steady-state humidity was studied by controlling the RH;the metastable hemihydrate was precipitated at 70.5%-77.1% RH,and the apparent crystal growth rate was between 1.42 and 2.33 μm3/s.Stable gypsum was formed at 80.7%-82.2% RH,and the apparent crystal growth rate was between 0.70 and 0.81 μm3/s.
