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Response of Groundwater to Climate Change under Extreme Climate Conditions in North china Plain

Journal of Earth Science 2014年第3期25卷 612-618页

作者： Ying Zhang Jincui Wang Jihong Jing Jichao Sun Institute of Hydrogeology and Environmental Geology Chinese Academy of Geological Sciences

The North china Plain（NCP） is one of the water shortage areas of china. Lack of water resources restricted the economic and social development of North china area and resulted in deterioration of ecosystem and natural environment. Influenced by the climate change and human activities, the water circulation of NCP was largely changed and the crisis of water resources was aggravated. Therefore, it is important to study the features of the extreme climate and the response mechanism of groundwater to climate change. We analyzed the trend of climate change and extreme climate features in the past 60 years based on the monitoring data of meteorological stations. And then the response characteristics of groundwater to climate change were discussed. The average temperature of NCP was in an obviously upward trend. The overall precipitation variation was in a downward trend. The climate change in this area showed a warming-drying trend. The intensity of extreme precipitation displayed a trend of declining and then increasing from north to south as well as declining from eastern coastal plain to the piedmont plain. Grey correlation degree analysis indicated that groundwater depth had a close relationship with precipitation and human activities in NCP. The response of groundwater level to precipitation differed from the piedmont alluvial-pluvial plain to the coastal plain. The response was more obvious in the coastal plain than the piedmont alluvial-pluvial plain and the middle plain. The precipitation influenced the groundwater depth both directly and indirectly. Under the condition of extreme precipitation, the impact would aggravate, in the forms of rapid or lag raise of groundwater levels.

关键词： climate change groundwater response grey correlation extreme precipitation.

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Automatic three-dimensional reconstruction based on four-view stereo vision using checkerboard pattern

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Journal of Central South University 2017年第5期24卷 1063-1072页

作者： XIONG Jie ZHONG Si-dong LIU Yong TU Li-fen School of Electronic Information Wuhan University School of Physics and Electronic Information Engineering Hubei Engineering University

An automatic three-dimensional(3D) reconstruction method based on four-view stereo vision using checkerboard pattern is presented. Mismatches easily exist in traditional binocular stereo matching due to the repeatable or similar features of binocular images. In order to reduce the probability of mismatching and improve the measure precision, a four-camera measurement system which can add extra matching constraints and offer multiple measurements is applied in this work. Moreover, a series of different checkerboard patterns are projected onto the object to obtain dense feature points and remove mismatched points. Finally, the 3D model is generated by performing Delaunay triangulation and texture mapping on the point cloud obtained by four-view matching. This method was tested on the 3D reconstruction of a terracotta soldier sculpture and the Buddhas in the Mogao Grottoes. Their point clouds without mismatched points were obtained and less processing time was consumed in most cases relative to binocular matching. These good reconstructed models show the effectiveness of the method.

关键词： three-dimensional reconstruction four-view stereo vision checkerboard pattern dense point

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Response of soil Olsen-P to P budget under different long-term fertilization treatments in a fluvo-aquic soil

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Journal of Integrative Agriculture 2019年第3期18卷 667-676页

作者： ZHANG Wei-wei ZHAN Xiao-ying ZHANG Shu-xiang Khalid Hamdan Mohamed Ibrahima XU Ming-gang Institute of Agricultural Resources and Regional Planning Chinese Academy of Agricultural Sciences College of Urban and Environmental Sciences Peking University

The concentration of soil Olsen-P is rapidly increasing in many parts of china, where P budget(P input minus P output) is the main factor influencing soil Olsen-P. Understanding the relationship between soil Olsen-P and P budget is useful in estimating soil Olsen-P content and conducting P management strategies. To address this, a long-term experiment(1991–2011) was performed on a fluvo-aquic soil in Beijing, china, where seven fertilization treatments were used to study the response of soil Olsen-P to P budget. The results showed that the relationship between the decrease in soil Olsen-P and P deficit could be simulated by a simple linear model. In treatments without P fertilization(CK, N, and NK), soil Olsen-P decreased by 2.4, 1.9, and 1.4 mg kg^(–1) for every 100 kg ha^(–1) of P deficit, respectively. Under conditions of P addition, the relationship between the increase in soil Olsen-P and P surplus could be divided into two stages. When P surplus was lower than the range of 729–884 kg ha^(–1), soil Olsen-P fluctuated over the course of the experimental period with chemical fertilizers(NP and NPK), and increased by 5.0 and 2.0 mg kg^(–1), respectively, when treated with chemical fertilizers combined with manure(NPKM and 1.5 NPKM) for every 100 kg ha^(–1) of P surplus. When P surplus was higher than the range of 729–884 kg ha^(–1), soil Olsen-P increased by 49.0 and 37.0 mg kg^(–1) in NPKM and 1.5 NPKM treatments, respectively, for every 100 kg ha^(–1) P surplus. The relationship between the increase in soil Olsen-P and P surplus could be simulated by two-segment linear models. The cumulative P budget at the turning point was defined as the "storage threshold" of a fluvo-aquic soil in Beijing, and the storage thresholds under NPKM and 1.5 NPKM were 729 and 884 kg ha^(–1)P for more adsorption sites. According to the critical soil P values(CPVs) and the relationship between soil Olsen-P and P budget, the quantity of P fertilizers for winter wheat could be increased

关键词： long-term fertilization fluvo-aquic soil Olsen-P P budget critical soil P value

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CRA-40/Atmosphere—The First-Generation Chinese Atmospheric Reanalysis(1979–2018):System Description and Performance Evaluation

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Journal of Meteorological Research 2023年第1期37卷 1-19页

作者： Zhiquan LIU Lipeng JIANG Chunxiang SHI Tao ZHANG Zijiang ZHOU Jie LIAO Shuang YAO Jingwei LIU Minyan WANG Huiying WANG Xiao LIANG Zhisen ZHANG Yan YAO Ting ZHU Zhe CHEN Wenhui XU Lijuan CAO Hui JIANG Kaixi HU national Meteorological Information Centre China Meteorological Administration(CMA)Beijing 100081China national Center for Atmospheric Research BoulderCO 80301USA CMA Earth System Modeling and Prediction Centre China Meteorological AdministrationBeijing 100081China

Atmospheric reanalysis reproduces the past atmospheric conditions through assimilation of historical meteorological observations with fixed version of a numerical weather prediction(NWP)model and data assimilation(DA)*** is widely used in weather,climate,and even business-related research and *** paper reports the development of CMA’s first-generation global atmospheric reanalysis(RA)covering 1979–2018(CRA-40;CRA refers to CMA-RA).CRA-40 is produced by using the Global Spectral Model(GSM)/Gridpoint Statistical Interpolation(GSI)at a 6-h time interval and a TL574 spectral(34-km)resolution with the model top at 0.27 hPa.A large number of reprocessed satellite data and widely collected conventional observations were assimilated during the reanalyzing process,including the reprocessed atmospheric motion vector(AMV)products from FY-2C/D/E/G satellites,dense conventional observations(at about 120 radiosonde and 2400 synoptic stations)over china,as well as MWHS-2 and GNSS-RO observations from *** reanalysis fitting to observations is improved over time,especially for surface pressure with root-mean-square error reduced from 1.05 hPa in 1979 to 0.8 hPa,and for upper air temperature from 1.65 K in 1979 to 1.35 K,in *** patterns of global analysis increments for temperature,specific humidity,and zonal wind are consistent with the changes in the observing *** surface temperature from the model’s 6-h forecast reflects the global warming trend *** CRA-40 precipitation pattern matches well with those of GPCP and other ***-40 also successfully captures the QBO and its vertical and temporal development,hemispherical atmospheric circulation change,and moisture transport by the East Asian summer *** is now operationally running in near real time as a climate data assimilation system in CMA.

关键词： CMA reanalysis(CRA) observations data assimilation(DA) forecast model

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CHEBYSHEV FINITE SPECTRAL METHOD FOR 2-D EXTENDED BOUSSINESQ EQUATIONS

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Journal of Hydrodynamics 2011年第1期23卷 1-11页

作者： LI Yok-sheung ZHAN Jie-min, SU Wei Department of Civil and Structural Engineering The Hong Kong Polytechnic University Hong Kong China Department of Applied Mechanics and Engineering Sun Yat-sen University Guangzhou 510275 China

In this article,an accurate Chebyshev finite spectral method for the 2-D extended Boussinesq equations is *** method combines the advantages of both the finite difference and spectral *** Adams-Bashforth predictor and the fourth-order Adams-Moulton corrector are adopted for the numerical solution of the governing differential *** efficient wave absorption strategy is also proposed to effectively absorb waves at outgoing wave boundaries and reflected waves from the interior of the computational domain due to barriers and bottom slopes at the incident wave boundary to avoid contamination of the specified incident wave *** proposed method is verified by a case where experimental data are available for comparison for both regular and irregular *** case is wave diffraction over a shoal reported by Vincent and *** results agree very well with the corresponding experimental data.

关键词： Chebyshev polynomial finite spectral method irregular waves

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Phosphate-induced differences in stabilization efficiency for soils contaminated with lead, zinc, and cadmium

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Frontiers of Environmental Science & Engineering 2018年第2期12卷 97-105页

作者： Jie Ren Zhuo Zhang Mei Wang Guanlin Guo Ping Du Fasheng Li College of Water Sciences Belling Normal Unive~ity Beijing 100875 China State Key Laboratory of Environmental Criteria and Risk Assessment Chinese Research Academy of Environmental Sciences Beijing 100012 China

Phosphates can cost-effectively decrease the mobility of Pb in contaminated soils. However, Pb always coexists with other metals in soil, their competitive reactions with phosphates have not been tested. In this study, the abilities of KHzPO4, K2HPO4, and K3PO4 to stabilize Pb, Zn, and Cd in soils contaminated with a single metal or a ternary metal for different phosphorus/metal molar ratios were investigated. Results indicated that the stabilization efficiency of KH2PO4, K2HPO4, and K3PO4 for Pb, Zn, and Cd in single metal contaminated soil （P/M ratio 0.6） was 96.00%-98.74%, 33.76%-47.81%, and 9.50%-55.79%, respectively. Competitive stabilization occurred in the ternary system, Pb exhibited a strong competition, the stabilization efficiency of Zn and Cd reduced by 23.50%- 31.64%, and 7.10%--39.26%, respectively. Pyromorphite and amorphous lead phosphate formed with excess KH2PO4 or K2HPO4 addition, while K3PO4 resulted in the formation of a hydroxypyr- omorphite precipitate. Amorphous Zn and Cd phosphates and hydroxides were the primary products. The immobilization rate of Zn and Cd depends on pH, and increased significantly in response to the excess phosphate application. This approach provides insight into phosphate-induced differences in stabilization efficiency in soils contaminated with multiple metals, which is of theoretical and engineering significance.

关键词： Heavy metals Metal-contaminated soil Phosphate Competitive stabilization

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Arsenic dynamics in the rhizosphere and its sequestration on rice roots as affected by root oxidation

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Journal of Environmental Sciences 2014年第4期26卷 892-899页

作者： Weisong Pan Chuan Wu Shengguo Xue William Hartley Institute of Environmental Engineering School of Metallurgical Science and Engineering Central South University College of Bioscience and Biotechnology Hunan Agricultural University Crop and Environment Sciences Department Harper Adams University

A pot experiment was conducted to investigate the effects of root oxidation on arsenic （As） dynamics in the rhizosphere and As sequestration on rice roots. There were significant differences （P 〈 0.05） in pH values between rhizosphere and non-rhizosphere soils, with pH 5.68-6.16 in the rhizosphere and 6.30-6.37 in non-rhizosphere soils as well as differences in redox potentials （P 〈 0.05）. Percentage arsenite was lower （4%-16%） in rhizosphere soil solutions from rice genotypes with higher radial oxygen loss （ROL） compared with genotypes with lower ROL （P 〈 0.05）. Arsenic concentrations in iron plaque and rice straw were significantly negatively correlated （R = -0.60, P 〈 0.05）. Genotypes with higher ROL （TD71 and Yinjingmanzhau） had significantly （P 〈 0.001） lower total As in rice grains （1.35 and 0.96 mg/kg, respectively） compared with genotypes with lower ROL （IAPAR9, 1.68 mg/kg; Nanyangzhan 2.24 mg/kg） in the As treatment, as well as lower inorganic As （P 〈 0.05）. The present study showed that genotypes with higher ROL could oxidize more arsenite in rhizosphere soils, and induce more Fe plaque formation, which subsequently sequestered more As. This reduced As uptake in aboveground plant tissues and also reduced inorganic As accumulation in rice grains. The study has contributed to further understanding the mechanisms whereby ROL influences As uptake and accumulation in rice.

关键词： arsenic iron plaque rhizosphere radial oxygen loss rice

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Meta-analysis of the effect of low-level occupational benzene exposure on human peripheral blood leukocyte counts in china

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Journal of Environmental Sciences 2022年第4期34卷 204-210页

作者： Hao Zhang Hong Li Zhijian Peng Juan Cao Jiemeng Bao Lei Li Xuezhong Wang Yuanyuan Ji Zhuojiong Chen School of Science China University of GeosciencesBeijing 100083China State Key Laboratory of Environmental Criteria and Risk Assessment Chinese Research Academy of Environmental SciencesBeijing 100012China Academy of Environmental Planning and Design Co.Ltd.Nanjing UniversityNanjing 210093China College of Earth Sciences Jilin UniversityChangchun 130061China

To investigate the effect of low-level occupational benzene exposure on human peripheral blood leukocyte counts of the workers,domestic and foreign published research data on the change of human peripheral blood leukocyte counts under low-level occupational benzene exposure from January 1990 to December 2020 were collected and *** to the literature inclusion and exclusion criteria,18 independent studies from 12 publications were selected for meta-analysis to explore the effect of low-level occupational benzene exposure on human peripheral blood leukocyte *** results showed that the peripheral blood leukocyte counts abnormal rates of low-level occupational benzene exposure group were higher than those of the control group,and the difference was statistically ***-level occupational benzene exposure could result in a relatively higher abnormal rate of peripheral blood leukocyte counts in the exposed population,indicating that low-level occupational benzene exposure at workplaces specified by the current benzene occupational exposure limit in china would affect the peripheral blood leukocyte counts of the workers,thus benzene with concentrations under the limit in the ambient air of workplace could be still harmful to the health of the exposed *** results of this study could provide a scientific basis for future revision of the benzene occupational exposure limit in china,and could also be a reference for the formulation of environmental standard concerning benzene in china in the future.

关键词： Benzene at workplaces Low-level occupational exposure Peripheral blood Leukocyte Meta-analysis

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Interannual to Decadal Variability of the Winter Aleutian Low Intensity During 1900-2004

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Acta meteorologica Sinica 2011年第6期25卷 710-724页

作者：陈阳翟盘茂 State Key Laboratory of Severe Weather Chinese Academy of Meteorological Sciences CMA

A new winter Aleutian Low （AL） intensity index was defined in this paper. A centurial-long time series of this index was constructed using the sea level pressure （SLP） data of nearly 100 years. The features of interannual and decadal variability of the winter AL intensity since 1900 were analyzed by applying the wavelet analysis. The relationship between the winter AL intensity and atmospheric circulation was examined. The cross-wavelet analysis technique was used to further reveal the relationship between the AL intensity and sea surface temperature （SST） in the equatorial eastern Pacific （EEP） and tropical Indian Ocean （TIO） in winter. The results indicate that： 1） On the interannual timescale, the winter AL intensity displays 3 7-yr oscillations, while on the decadal timescale, 8-10-yr and 16 22-yr oscillations are more obvious. 2） Of the linkage to atmospheric circulation, both AO （Arctic Oscillation） and PNA （Pacific North America pattern） are closely associated with winter AL intensity on the interannual timescale, but only PNA contributes to the variation of winter AL intensity on the decadal timescale. 3） As to the ocean impact, winter EEP SST is a major factor affecting the winter AL intensity on the interannual timescale, especially on the 3 7-yr periods. However, on the decadal timescale, though both the TIO and EEP SSTs are associated with the AL intensity in winter, the TIO SST impact is more significant.

关键词： the Aleutian Low sea surface temperature cross-wavelet analysis variability

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Retrieval of Atmospheric Temperature and Moisture Vertical Profiles from Satellite Advanced Infrared Sounder Radiances with a New Regularization Parameter Selecting Method

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Journal of Meteorological Research 2016年第3期30卷 356-370页

作者：张堃吴春强李俊 Chinese Academy of Meteorological Sciences Beijing 100081China national Satellite Meteorological Center Beijing 100081China Cooperative Institute for Meteorological Satellite Studies University of Wisconsin-MadisonMadisonWI 53706USA

Considering the characteristics of nonlinear problems,a new method based on the L-curve method and including the concept of entropy was designed to select the regularization parameter in the one-dimensional variational analysis-based sounding retrieval *** the first iteration,this method uses an empirical regularization parameter derived by minimizing the entropy of *** subsequent iterations,it uses the L-curve method to select the regularization parameter in the vicinity of the regularization parameter selected in the last *** new method was employed to select the regularization parameter in retrieving atmospheric temperature and moisture profiles from Atmospheric Infrared Sounder radiance measurements selected from the first day of each month in *** results show that compared with the original L-curve method,the new method yields 5.5%and 2.5%improvements on temperature and relative humidity profiles,*** with the discrepancy principle method,the improvements on temperature and relative humidity profiles are 1.6%and 2.0%,respectively.

关键词： Atmospheric Infrared Sounder retrieval entropy L-curve regularization parameter

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