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Formation and Movement of Groundwater in the Thick Loess-Palaeosol Sequences of the Chinese Loess Plateau

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Pedosphere 2018年第6期28卷 895-904页

作者： MA Yandong ZHAO Jingbo LIU Rui ZHOU Qi YIN Leipeng School of Geography and Tourism Shaanxi Normal University State key laboratory of Loess and Quaternary Geology Institute of Earth Environment Chinese Academy of Sciences Department of Basic Science Engineering University of Armed Police Force key laboratory of disaster monitoring and mechanism simulating of shaanxi province Baoji University of Arts and Sciences

Permeability and water-bearing space are important hydrological characteristics of the loess strata. In this study a systematic experiment was conducted to measure the magnetic susceptibility, grain size, porosity, and infiltration rate of the loess and palaeosol layers on a loess tableland of the central Chinese Loess Plateau, in order to investigate the differences in hydrological conditions between the loess and palaeosol layers. The magnetic susceptibility of the loess layer was lower than that of the palaeosol layer, but the average quasi-steady infiltration rate was about 0.31 mm min^(-1) higher, the coarse silt and very fine sand contents were about7.1% greater, and the porosity was about 5.7% higher. These differences were mainly due to pedogenesis, which was affected by the Quaternary climate. The pedogenesis differences between the loess and palaeosol layers resulted in hydrological property differences in terms of permeability and water-bearing space. The loess layer had a higher permeability and more water-bearing space than the palaeosol layer, which meant that the loess layer is more likely to form aquifers and the palaeosol layer is more prone to form *** groundwater in the loess strata had a multilayered characteristic, which depended on the relative impermeability of palaeosol layer and the alternate deposition of loess-palaeosol layers. The hydrological characteristics of the loess strata demonstrated that the Quaternary climate had an important control function on the formation and movement of groundwater. This knowledge provides a reliable theoretical basis for water resource development and utilization on the Chinese Loess Plateau, and this study extends the application of Quaternary climate change theory to hydrological systems in loess deposits.

关键词： aquifer aquitard grain size magnetic susceptibility pedogenesis permeability Quaternary climate

The spike weight contribution of the photosynthetic area above the upper internode in a winter wheat under different nitrogen and mulching regimes

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The Crop Journal 2019年第1期7卷 89-100页

作者： Wei Chen Jingjuan Zhang Xiping Deng key laboratory of disaster monitoring and mechanism simulating of shaanxi province Baoji University of Arts and Sciences State key laboratory of Soil Erosion and Dryland Farming on the Loess Plateau Institute of Soil and Water Conservation Northwest A&F University and Chinese Academy of Sciences School of Veterinary and Life Sciences Murdoch University

Besides leaves, non-foliar green organs such as stem and spike are also considered photosynthetic organs. To assess the photosynthetic contributions of these organs, the correlations between these photosynthetic areas and single-spike weight were investigated in a winter wheat(Triticum aestivum L.) under four nitrogen and mulching treatments: N120,N150, N195, and N195 + M. Two-year repeated field experiments were conducted on the Loess Plateau of China. Non-foliar photosynthetic area, grain-filling ratio and duration,grain yield, and in particular, single-spike weight, were measured, recorded and *** the N195 + M treatment, plants showed the largest area of photosynthetic organs(flag leaf and non-foliar organs) and the highest grain yield and single spike weight. Singlespike weight was positively correlated with the areas of all examined non-foliar photosynthetic organs, in particular with the area above the flag leaf node(R^2= 0.761*)and the area above the exposed part of the peduncle(EXP)(R^2= 0.800**). In addition, singlespike weight was highly correlated with average grain-filling ratio(R^2= 0.993**), whereas it was less highly correlated with grain-filling duration(R^2= 0.533). The morphological traits of non-foliar photosynthetic organs were also more highly correlated with average grainfilling ratio than with average grain-filling duration. The significant correlation between each of the morphological traits(area, length and width) of EXP and single-spike weight indicates that morphological traits of EXP are important in determining spike weight in the Loess Plateau environment.

关键词： Grain-filling ratio Grain-filling duration Loess Plateau Photosynthetic organs Single spike weight Winter wheat

Simulation of Ground Motion at Guanting Reservoir Dam Based on the Scenario Earthquake in the Yanqing-Huailai Basin

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Earthquake Research in China 2009年第4期23卷 458-466页

作者： Wen Yanjun key lab. of disaster monitoring and mechanism simulating of shaanxi province Baoji University of Arts and Science Baoji 721013Shaanxi China

Research at home and abroad shows that the simulation of ground motion using the 3D finite-difference method might be accurate and feasible. Based on related theories and methods,and using the wave velocity and density model of the crust in the Yanqing-Huailai Basin,this paper makes a simulation of ground motion at Guanting Reservoir Dam based on the scenario earthquake in the Yanqing-Huailai Basin. Comparative analysis shows that the results of 3D finite-difference simulation accord with those of the empirical formula. The parameters such as the velocity-time series of ground motion,PGV and frequency might be referred to for the analysis of seismic protection design of the dam's structure.

关键词： Yanqing-Huailai Basin Guanting Reservoir Dam Scenario earthquake Simulation of ground motion

Winter wheat yield improvement by genetic gain across different provinces in China

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Journal of Integrative Agriculture 2024年第2期23卷 468-483页

作者： Wei Chen Jingjuan Zhang Xiping Deng key laboratory of disaster monitoring and mechanism simulating of shaanxi province/School of Geography and Environment Baoji University of Arts and SciencesBaoji 721013China Centre for Crop and Food Innovation Murdoch University90 South StreetMurdochWA 6150Australia State key laboratory of Soil Erosion and Dryland Farming on the Loess Plateau Northwest A&F UniversityYangling 712100China

The replacement of winter wheat varieties has contributed significantly to yield improvement worldwide,with remarkable progress in *** on two sets of data,production yield from the National Bureau of Statistics of China and experimental yield from literature,this study aims to(1)illustrate the increasing patterns of production yield among different provinces from 1978 to 2018 in China,(2)explore the genetic gain in yield and yield relevant traits through the variety replacement based on experimental yield from 1937 to 2016 in China,and(3)compare the yield gap between experimental yield and production *** results show that both the production and experimental yields significantly increased along with the variety *** national annual yield increase ratio for the production yield was 1.67%from 1978 to 2018,varying from 0.96%in Sichuan province to 2.78%in Hebei province;such ratio for the experimental yield was 1.13%from 1937 to *** yield gap between experimental and production yields decreased from the 1970s to the *** study reveals significant increases in some yield components consequent to variety replacement,including thousand-grain weight,kernel number per spike,and grain number per square meter;however,no change is shown in spike number per square *** biomass and harvest index consistently and significantly increased,whereas the plant height decreased significantly.

关键词： genetic gain winter wheat yield yield components

Assessment of Environmental Carrying Capacity Using Principal Component Analysis

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Journal of Geoscience and Environment Protection 2018年第3期6卷 54-65页

作者： Yinge Liu Junhui Zhang Shaoxiong Wang Yan Wang Aling Zhao key laboratory of disaster monitoring and mechanism simulating in shaanxi province College of Geography and Environment Baoji University of Arts and Sciences Baoji China

Regional environmental carrying capacity (ECC) is nonlinear and spatially specific. A hierarchy index system including resources, environmental and socio-economic elements was established using an analytic hierarchy process. Principal component analysis (PCA) was used to estimate the regional size and differences of environmental carrying capacities. Main information of four principal components, i.e., carrying capacity of resources supply, carrying capacity of environmental quality, carrying capacity of social economy and carrying capacity of infrastructure construction, was extracted. The ECC evaluation value was divided into five levels of lowest carrying capacity, low carrying capacity, medium carrying capacity, high carrying capacity and highest carrying capacity, respectively. The results showed that on the whole ECC was at the medium carrying capacity level. ECC was generally highest in Guanzhong plain, followed by Loess Plateau, and was lowest in Qiba mountain. The carrying capacity of water resources and environmental quality was relatively low, and the infrastructure carrying capacity was highest among the four components. The temporal spatial variation of ECC was closely related to vulnerability of the natural resources and environment in the regions. Verification was proven that PCA was a useful tool when applied to evaluate ECC and reflect the spatial distribution of large-quantity ECC indices on a large regional scale. This study provides a basis for comprehensive understanding of resources, environment and management for regional balanced development.

关键词： Environmental Carrying Capacity Principal Component Analysis Spatial Dif-ference Evaluation of Indicators

Climate change and its impacts on mountain glaciers during 1960–2017 in western China

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Journal of Arid Land 2019年第4期11卷 537-550页

作者： LIU Yinge WANG Ninglian ZHANG Junhui WANG Lingang key laboratory of disaster monitoring and mechanism simulating in shaanxi province College of Geography andEnvironmentBaoji University of Arts and ScienceBaoji721013China State key laboratory of Cryosphere Science Northwest Institute of Eco-Environment and ResourcesChinese Academy ofSciencesLanzhou730000China College of Urban and Environmental Science Northwest UniversityXi'an710127China

Mountain glaciers are highly sensitive to climate change. In this paper, we systematically analyzed and discussed the responses of glaciers to climate change during 1960–2017 in western China by the methods of least squares and correlation analysis. Results show that the maximum temperature, minimum temperature, average temperature, and precipitation significantly increased in western China at the rates of 0.32°C/10 a, 0.48°C/10 a, 0.39°C/10 a, and 11.20 mm/10 a, respectively. However, the wind speed, hours of sunshine, snowfall, and snowy days displayed decreasing trends at the rates of –0.53 m/(s·10 a), 3.72 h/10 a, –2.90 mm/10 a, and –0.10 d/10 a, respectively. The annual percentage of glacier area decreased by approximately 0.42%, and the average glacier area decreased by 2.76 km^2/a. Meanwhile, glacial shrinkages were greater in the Altay Mountains, Tanggula Mountains, and Qilian Mountains than in the other mountainous regions. Glacier accumulation decreased while melt volume increased at a rate of 2.7×10~4 m^3/a. The area of melt volume was 1.3 times that of the glacier accumulation area. The glacier mass balance(GMB) decreased substantially at a rate of –14.0 mm/a, whereas the equilibrium line altitude(ELA) showed an increasing trend at a rate of 0.5 mm/a. After 1997, the mass was smaller than –500.0 mm, indicating a huge loss in glaciers. Furthermore, relationships between ELA and GMB and various climatic factors were established. Temperature and precipitation demonstrated a significantly negative correlation, whereas wind speed and snowy days had significantly positive correlations with GMB. Snowy days also exhibited a remarkably negative correlation with ELA. The strong warming trend and less snowy days were thought to be the main factors leading to glacial melting, whereas the increase in precipitation, and reductions of sunshine hours and wind speed might slow glacial melting.

关键词： temperature precipitation climate trend glacier variation impacts western China

Recharge sources and chemical composition types of groundwater and lake in the Badain Jaran Desert, northwestern China

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Journal of Geographical Sciences 2012年第3期22卷 479-496页

作者： SHAO Tianje ZHAO Jingbo ZHOU Qi DONG Zhibao MA Yandong College of Tourism and Environment Science Shaanxi Normal University key laboratory of disaster monitoring and mechanism simulating of shaanxi province Baoji University of Arts and Sciences Cold and Arid Regions Environmental and Engineering Research Institute CAS

Based on the analysis of ion chemical composition of lake water and shallow groundwater in the Badain Jaran Desert, this paper discussed the characteristics of ion chemical composition, spatial variation of lake water, and possible supply sources of lake water and groundwater in the desert areas. The results show that the pH, salinity, TDS and electrical conductivity of the lake water are greater than those of groundwater. The ion contents of water samples are dominated by Na^＋ and Cl^-. Most of the higher salinity lakes are Na （K）-CI-（SO4） type, and a few of low salinity lakes belong to the Na-（Mg）-（Ca）-Cl-（SO4）-（HCO3） type. Most of the groundwater is Na-（Ca）-（Mg）-Cl-（SO4）-（HCO3） type, attributed to subsaline lake, and only a few present the Na-Cl-SO4 type, flowing under saline lake. The pH, salinity, TDS and electrical conductivity in the southeastern lakes are relatively low, and there are slightly alkaline lakes. The pH, salinity, TDS and electrical conductivity in the northern lakes are much greater than those of the southeastern lakes, and the northern lakes are moderately alkaline and saline ones. In the southeastern part of the Badain Jaran Desert, the ion chemical characteristics of the lake water from south to north show a changing trend of subsaline →saline→hypersaline. The changing trend of chemical compositions of ions in recent 9 years indicates that most of the ion contents have a shade of reduction in Boritaolegai, Badain, Nuoertu and Huhejilin lakes, which state clearly that the amount of fresh water supply is increasing in the 9-year period. The ion chemical composition of the lake water reveals that the flow direction of lake water is from southeast to northwest in the Badain Jaran Desert. The ion chemical composition, moisture content of sand layer water level height and hierarchical cluster analysis of the lake water and groundwater demonstrate that the lake water is mainly supplied by local rainfall and infiltration of precipitation in Yabulai

关键词： chemical composition desert lake spatial variation hierarchical cluster analysis supply source Badain Jaran Desert

A tree-ring-based reconstruction of the Yimin River annual runoff in the Hulun Buir region,Inner Mongolia,for the past 135 years

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Chinese Science Bulletin 2012年第36期57卷 4765-4775页

作者： BAO Guang LIU Yu LIU Na key laboratory of disaster monitoring and mechanism simulating of shaanxi province Baoji University of Arts and SciencesBaoji 721013China The State key laboratory of Loess and Quaternary Geology Institute of Earth EnvironmentChinese Academy of SciencesXi'an 710075China Department of Environmental Science and Technology School of Human Settlements and Civil EngineeringXi'an Jiaotong University Xi'an 710049.China

Based on the relationships between the regional tree-ring chronology(RC) of moisture-sensitive Pinus sylvestris *** and the monthly mean maximum temperature,annual precipitation and annual runoff,a reconstruction of the runoff of the Yimin River was performed for the period *** model was stable and could explain 52.2% of the variance for the calibration period of *** the past 135 years,21 extremely dry years and 19 extremely wet years *** years represented 15.6% and 14.1% of the total study period,*** severe drought events lasting two years or more occurred in 1950-1951,1986-1987,1905-1909,1926-1928,1968-1969 and *** wetter events occurred during 1954-1959,1932-1934,1939-1940 and *** with other tree-ring-based streamflow reconstructions or chronologies for surrounding areas supplied a high degree of confidence in our *** spectrum and wavelet analyses suggested that the reconstructed annual runoff variation in the Hulun Buir region and surrounding area could be associated with large-scale atmospheric-oceanic variability,such as the Pacific Decadal Oscillation(PDO) and El Ni o-Southern Oscillation(ENSO),and sunspot activity.

关键词：呼伦贝尔地区年径流量伊敏河内蒙古基础太平洋年代际振荡樟子松人工林平均最高气温

Dynamic Characteristics and Influencing Factors of Groundwater Level in Qianyang County

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Meteorological and Environmental Research 2016年第4期7卷 44-49页

作者： Zhao Dan Zhou Qi Jing Yanxia key laboratory of disaster and monitoring and mechanism simulating of shaanxi province Baoji University of Arts and Sciences Baoji 721013 China Qianyang Soil and Water Conservation Station Qianyang 721100 China

The dynamic characteristics and influencing factors of groundwater level in Qianyang County were *** results showed that in the south bank of the Qianhe River,the change of groundwater level was mainly affected by precipitation,and the response of the groundwater level to the change of precipitation was one year *** groundwater level presented a downward trend on the *** the north bank of the Qianhe River,the supply source of the groundwater level included precipitation and hydrology,and the groundwater level showed a rising trend on the *** the plain area,there was a sudden change in the groundwater level under the control of human *** a word,the main factors influencing the groundwater level in various geological conditions were different,so there were great differences between various regions in the dynamic characteristics of the groundwater level in Qianyang County.

关键词： Groundwater level Dynamic characteristics Influencing factors Qianyang County China