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Combined effects of elevated temperature and CO_2 concentration on Cd and Zn accumulation dynamics in Triticum aestivum L.

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Journal of environmental sciences 2016年第9期28卷 109-119页

作者： Xiaoheng Wang Yu Li Hong Lu Shigong Wang College of Earth and environmental sciences Lanzhou University School of Chemical Engineering Northwest University for Nationalities department of Gastroenterology First Hospital of Lanzhou University School of atmospheric sciences Chengdu University of Information Technology College of atmospheric sciences Lanzhou University

A simulated climate warming experiment was conducted to evaluate the combined effects of elevated temperature and CO_2 concentration on the bioaccumulation,translocation and subcellular distributions of Cd and Zn in wheat seedlings（Triticum aestivum *** 1.） at Dingxi,Gansu Province,*** objective was to find evidence that global climate change is affecting the bioaccumulation of Cd and Zn in *** *** *** results showed that compared to control A,elevated temperature and CO_2 increased Cd bioaccumulation in the shoots by 1.4–2.5 times,and increased that in the roots by 1.2–1.5times,but decreased Zn levels in wheat shoots by 1.4–2.0 times,while decreased that in the roots by 1.6–1.9 ***,temperature and CO_2 concentration increase also led to increased Cd concentration,and decreased Zn concentration in subcellular compartments of wheat *** largest Cd concentration increase（174.4%） was observed in the cell wall and debris fractions of shoots after they were subjected to the highest CO_2 and temperature treatment（TC3）.The largest Zn concentration decrease（53.1%） was observed in the soluble（F3） fractions of shoots after they were subjected to the medium CO_2 and temperature treatment（TC2）.The temperature and CO_2 increase had no significant effect on the proportional distribution of Cd and Zn in the subcellular *** root-to-shoot translocation of Cd increased with the increasing temperature and CO_2 ***,the Zn distributions only fluctuated within a small range.

关键词： Climate warming Elevated CO_2 Elevated temperature Trace elements Wheat

Experiment on Dust Flux During Duststorm Periods over Desert Area

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Acta meteorologica Sinica 2008年第2期22卷 239-247页

作者：张宏升朱好彭艳康凌陈家宜 Soon-Ung PARK Center of Sino-Korcan atmospheric sciences Department of Atmospheric SciencesPeking University Center of Sino-Korean atmospheric sciences Department of Atmospheric SciencesPeking University Center of Sino-Korean atmospheric sciences Department of Atmospheric SciencesSeoul National UniversitySeoul 151-742Korea

The present study investigates the characteristics of turbulent transfer and the conditions for dust emission and transport using the dust concentration and micrometeorological data obtained during dust events occurring in the spring of 2004 over the Hunshandake desert area. The turbulent exchange coefficients and turbulent fluxes of momentum and heat are calculated. The relationships between dust flux, friction velocity, and wind speed are also explored. The results show that thermal turbulence is dominant during daytime of non-dusty days. The dynamic turbulence increases obviously and the sensible heat flux reduces by different degrees during dust events. There is an efficient downward transfer of momentum before duststorm occurrence, and both the dynamic turbulence and the thermal turbulence are important in the surface layer. The dynamic turbulence even exceeds the thermal turbulence during severe duststorm events. The values of dust flux vary in the range of -5 5, -30 30, and -200-300 μg m^-2 s^-1 during non-dusty days, blowing dust, and duststorm events, respectively. A slight upward transport of dust is observed during non-dusty days. The dust flux gradually varies from positive to negative during duststorm periods, which indicates the time evolution of dust events from dust rising to stably suspending and then deposition. The dust flux is found to be proportional to u＊^3. The threshold values of wind speed and friction velocity are about 6 and 0.4 m s^-1, respectively.

关键词： turbulent transfer dust flux threshold friction velocity dust event Hunshandake desert area

A Multifunctional HTDMA System with a Robust Temperature Control

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Advances in atmospheric sciences 2009年第6期26卷 1235-1240页

作者：叶兴南陈天翼胡大伟杨新陈建民张人一 Alexei F.KHAKUZIV 王琳 department of environmental Science&Engineering Fudan University department of atmospheric sciences Texas A&M UniversityCollege Station

The hygroscopicity of atmospheric aerosols significantly influences their size distribution, cloud condensation nuclei ability, atmospheric residence time, and climate forcing. In order to investigate the hygroscopic behavior of aerosol particles and serious haze in China, a Hygroscopic Tandem Differential Mobility Analyzers （HTDMA） system was designed and constructed at Fudan University. It can function as a scanning mobility particle sizing system to measure particle size distribution in the range of 20-1000 nm in diameter, as well as a hygroscopicity analyzer for aerosol particles with diameters between 20-400 nm in the range of 20%-90% RH （relative humidity）. It can also measure the effect of uptake of inorganic acids or semiVOCs on the hygroscopic behavior of aerosols, such as typical inorganic salts in atmospheric dust or their mixtures. The performance tests show that the system measured particle size of the standard polystyrene latex spheres （PSLs） is 197 nm, which is in excellent agreement with the certified diameter D=199±6 nm, as well as a standard deviation of the repeated runs SD=8.9×10^-4. In addition, the measured hygroscopic growth factors of the model compounds, （NH4）2SO4 and NaNO3, agree with the Kohler theoretical curves. The results indicate that the HTDMA system is an excellent and powerful tool for studying the hygroscopic behavior of submicron aerosols and meets the demand required for laboratory research and fieldwork on atmospheric aerosols in China.

关键词： HTDMA hygroscopic behavior atmospheric aerosols set up evaluation

Relationship between the Circumglobal Teleconnection and Silk Road Pattern over Eurasian continent

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Science Bulletin 2019年第6期64卷 374-376页

作者： Fuli Zhou Renhe Zhang Jinping Han Chinese Academy of Meteorological sciences University of Chinese Academy of sciences department of atmospheric and Oceanic sciences & Institute of atmospheric sciences Fudan University

During boreal summer, two remarkable upper-level wave trains over Eurasia were documented in literature, i.e., Circumglobal Teleconnection (CGT) and Silk Road Pattern (SRP). They are widely discussed because of their influences throughout the entire midlatitude Eurasia. SRP was defined by 200 hPa meridional winds [1]. Enomoto et al.[2] found that the wave train influenced the climate variation over Japan when they detected the mechanism of Bonin High, and then named it as "Silk Road Pattern". SRP has 3 prominent action centers, which are located in west-central Asia, Mongolia and the Far East, respectively [3].

关键词： During boreal summer remarkable upper-level located in west-central Asia

An overview of emissions of SO2 and NOx and the long-range transport of oxidized sulfur and nitrogen pollutants in East Asia

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Journal of environmental sciences 2016年第6期28卷 13-25页

作者： Yu Qu Junling An Youjiang He Jun Zheng State Key Laboratory of atmospheric Boundary Layer Physics and atmospheric Chemistry Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China Chinese Research Academy of environmental sciences Beijing 100012 China China-ASEAN environmental Cooperation Center Ministry of Environmental Protection of the People's Republic of ChinaBeijing 100035 China

The long-range transport of oxidized sulfur（sulfur dioxide（SO2） and sulfate） and oxidized nitrogen（nitrogen oxides（NOx ） and nitrate） in East Asia is an area of increasing scientific interest and political concern. This paper reviews various published papers, including ground- and satellite-based observations and numerical simulations. The aim is to assess the status of the anthropogenic emissions of SO2 and NOx and the long-range transport of oxidized S and N pollutants over source and downwind region. China has dominated the emissions of SO2 and NOx in East Asia and urgently needs to strengthen the control of their emissions, especially NOx emissions. Oxidized S and N pollutants emitted from China are transported to Korea and Japan, due to persistent westerly winds, in winter and ***, the total contributions of China to S and N pollutants across Korea and Japan were not found to be dominant over longer time scales（e.g., a year）. The source–receptor relationships for oxidized S and N pollutants in East Asia varied widely among the different studies. This is because：（1） the nonlinear effects of atmospheric chemistry and deposition processes were not well considered, when calculating the source–receptor relationships;（2） different meteorological and emission data inputs and solution schemes for key physical and chemical processes were used; and（3） different temporal and spatial scales were employed. Therefore, simulations using the same input fields and similar model configurations would be of benefit, to further evaluate the source–receptor relationships of the oxidized S and N pollutants.

关键词： Long-range transport Sulfate Nitrate East Asia Source–receptor relationships

Influence of the Arctic on the Predictability of Eurasian Winter Extreme Weather Events

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Advances in atmospheric sciences 2020年第4期37卷 307-317页

作者： Guokun DAI Mu MU department of atmospheric and Oceanic sciences and Institute of atmospheric sciences Fudan UniversityShanghai 200438China

The linkage between the Arctic and midlatitudes has received much attention recently due to the rapidly changing *** investigations have been conducted to reveal the relationship between the Arctic and Eurasian extreme events from the perspective of climatological *** a prediction source for extreme events in Eurasia,Arctic conditions are crucial for extreme event ***,it is urgent to explore the Arctic influence on the predictability of Eurasian extreme events due to the large uncertainties in Arctic *** the sensitivity and nonlinearity of the atmospheric circulations in midlatitude to Arctic conditions,it is necessary to investigate the Arctic influences on Eurasian extreme weather events in case studies at weather time *** studies indicate that only perturbations in specific patterns have fast ***,the conditional nonlinear optimal perturbation approach is recommended for exploring the uncertainties in Arctic initial and boundary conditions and their synergistic effect on Eurasian extreme ***,the mechanism for extreme event formation may differ in different ***,more extreme cases should be investigated to reach robust conclusions.

关键词： Arctic uncertainties Eurasian extreme weather events synergistic effect optimization algorithms

Impacts of Coastal SST Variability on the East Asian Summer Monsoon

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Advances in atmospheric sciences 2007年第2期24卷 259-270页

作者：黄安宁张耀存高新房 department of atmospheric sciences Nanjing University

The impacts of the seasonal and interannual SST variability in the East Asia coastal regions （EACRSST） on the East Asian summer monsoon （EASM） have been examined using a regional climate model （PδRCM9） in this paper. The simulation results show that the correlation between the EACRSST and the EASM is strengthened after the mid-1970s and also the variability of the EACRSST forcing becomes much more important to the EASM interannual variability after the mid-1970s. The impacts of the EACRSST on the summer precipitation over each sub-region in the EASM region become weak gradually from south to north, and the temporal evolution features of the summer precipitation differences over North and Northeast China agree well with those of the index of EASM （IEASM） differences. The mechanism analyses show that different EACRSST forcings result in the differences of sensible and latent heat flux exchanges at the air-sea interface, which alter the heating rate of the atmosphere. The heating rate differences induce low level air temperature differences over East Asia, resulting in the differences of the land-sea thermal contrast （LSTC） which lead to 850 hPa geopotential height changes. When the 850 hPa geopotential height increases over the East Asian continent and decreases over the coast of East China and the adjacent oceans during the weakening period of weakens consequently. On the contrary, the EASM enhances during the strengthening period of the LSTC.

关键词： SST variability coastal oceans East Asian monsoon numerical simulations

Cloud Radiative Forcing Induced by Layered Clouds and Associated Impact on the atmospheric Heating Rate

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Journal of Meteorological Research 2015年第5期29卷 779-792页

作者：吕巧谊李积明王天河黄建平 department of atmospheric sciences Lanzhou University

A quantitative analysis of cloud fraction, cloud radiative forcing, and cloud radiative heating rate （CRH） of the single-layered cloud （SLC） and the multi-layered cloud （MLC）, and their differences is presented, based on the 2B-CLDCLASS-LIDAR and 2B-FLXHR-LIDAR products on the global scale. The CRH at a given atmospheric level is defined as the cloudy minus clear-sky radiative heating rate. The statistical results show that the globally averaged cloud fraction of the MLC （24.9%）, which is primarily prevalent in equatorial regions, is smaller than that of the SLC （46.6%）. The globally averaged net radiative forcings （NET CRFs） induced by the SLC （MLC） at the top and bottom of the atmosphere （TOA and BOA） and in the atmosphere （ATM） are -60.8 （40.9）, 67.5 （49.6）, and 6.6 （8.7） W m-2, respectively, where the MLC contributes approximately 40.2%, 42.4%, and 57% to the NET CRF at the TOA, BOA, and in the ATM, respectively. The MLC exhibits distinct differences to the SLC in terms of CRH. The shortwave CRH of the SLC （MLC） reaches a heating peak at 9.75 （7.5） km, with a value of 0.35 （0.60） K day-1, and the differences between SLC and MLC transform from positive to negative with increasing altitude. However, the longwave CRH of the SLC （MLC） reaches a cooling peak at 2 （8） km, with a value of -0.45 （-0.42） K day-1, and the differences transform from negative to positive with increasing altitude. In general, the NET CRH differences between SLC and MLC are negative below 7.5 km. These results provide an observational basis for the assessment and improvement of the cloud parameterization schemes in global models.

关键词： single-layered cloud multi-layered cloud cloud fraction cloud radiative forcing cloud radiativeheating rate

Accumulation of Pb,Cu,and Zn in native plants growing on contaminated sites and their potential accumulation capacity in Heqing,Yunnan

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Journal of environmental sciences 2008年第12期20卷 1469-1474页

作者： Sardar Khan department of Soil environmental sciences Research Center for Eco-Environmental Sciences department of environmental sciences University of Peshawar25120 Peshawar

Phytoremediation is one of the cost-effective and environmental friendly technologies used to remove contaminants from contaminated soils,which has been intensively studied during the last ***,few economical and effective remediation methods are available for the remediation of Pb contaminated *** study was conducted to assess the potential of 19 plants growing on contaminated sites in Pb mine *** and associated soil samples were collected and analyzed for total metal concentrati...

关键词： accumulation of Pb Cu and Zn cultivated crops accumulator lead mine remediation