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Yang Q.,Key Laboratory of Groundwater Resources and Environment
Clean - Soil, Air, Water | Year: 2017

Precipitation infiltration is the unique recharge source of groundwater in most arid areas. In this paper, we focus on the desert area of the Ordos Plateau by assessing the capability of water stable isotope analysis (δD-δ18O) to refine the understanding of groundwater recharge mechanism. In situ profile monitoring of temperature, moisture content, and isotopic sampling in unsaturated and saturated zones was conducted at the Bulanghe station located in the middle of the Ordos Plateau to identify the detailed infiltration process. It was found that the capillary zone has the most depleted heavy O and H isotopes in the profile. The analysis of δD-δ18O relationships of local precipitation explains the isotopic variability and indicates the following processes: (1) Liquid water evaporated at hotter layer near the surface; 2) Part of vapor moves downward and condensates at the deeper layer where it becomes cooler. The isotopic fractionation that occurs in this process makes the condensation zone the most depleted heavy O and H isotopes zone. Temperature and moisture content in the profile also supported the capillary zone as vapor moves downward. The isotopic evidence indicates that, except for direct infiltration, the newly found secondary infiltration pattern, vapor-liquid flow, makes it possible that the low intensity precipitation event contributes to groundwater recharge. The results from this study may provide useful insights into the identification of infiltration mechanism in arid areas in the world. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Wei R.,Key Laboratory of Groundwater Resources and Environment | Xiao C.,Key Laboratory of Groundwater Resources and Environment | Zhang Y.,Nanjing University of Information Science and Technology | Liang X.,Key Laboratory of Groundwater Resources and Environment
Jilin Daxue Xuebao (Diqiu Kexue Ban)/Journal of Jilin University (Earth Science Edition) | Year: 2014

The 0-1 test is a new binary test to decide the regular or chaotic motions, which is applied directly to time series data and does not require phase space reconstruction. It is proved to be an effective test after test for chaos of Chebyshev map. The 0-1 test was carried out on monthly precipitation time series from 1958 to 2011 of 640 meteorological stations of China, and the density-based spatial clustering algorithm considering both spatial proximity and attribute similarity (DBSC) was used to perform spatial clustering. It is showed that monthly precipitation time series of all stations are chaotic, further more, the spatial distribution of K shows significant characteristic with spatial variability. In the large-scale, the country can be divided into four sub-regions, that are northwest with the highest K value, southern with the second highest, north and northeast with median and Qingzang district with the lowest. In the small-scale, 29 spatial clusters are found considering both spatial location and chaos degrees. The chaotic spatial clustering results not only coincide with the large-scale distributions of climate types, but also reflect the local variation of precipitation systems, which provides a new approach and methodology to study the temporal and spatial variation of precipitation systems.


Zhang B.,Key Laboratory of Groundwater Resources and Environment | Zhang B.,Jilin University | Hong M.,Key Laboratory of Groundwater Resources and Environment | Hong M.,Jilin University | And 3 more authors.
Hydrological Processes | Year: 2013

This study integrates a simple overland flow module (isochronous cells model) with the river module of MODFLOW such that temporal and spatial interactions between stream flow and groundwater can be simulated using net rainfall data of a watershed. The isochronous cells model is an efficient travel time runoff approach based on geographic information system (GIS) that considers both spatial and temporal variations of net rainfall through hill slope of the watershed. This overland module is easily coupled with MODFLOW river routing module. Specifically, the stream flow from the isochronous cells model is directly assigned to both sides of river cells of the MODFLOW model. Such an integration of MODFLOW and isochronous cells model is especially useful in watersheds where river flow data are limited. The feasibility of this integrated model was demonstrated using a case study in the middle and downstream regions of the Yitong River watershed, China. © 2012 John Wiley & Sons, Ltd.


Yu Z.,Jilin University | Zhang Y.,Jilin University | Zhang Y.,Key Laboratory of Groundwater Resources and Environment | Zhang Q.,Jilin University | Xu T.,Key Laboratory of Groundwater Resources and Environment
Jilin Daxue Xuebao (Diqiu Kexue Ban)/Journal of Jilin University (Earth Science Edition) | Year: 2013

THM coupling analysis in porous medium has an important research significance in geological sciences such as nuclear waste geological storage, hot dry rock, CO2 geological storage, etc., in which numerical method is often required in view of its computational complexity. TOUGHREACT is joined together with FLAC3D using grid conversion between the corner points and center point as well as three dimension three point Lagrange interpolation methods, and realizes the multiphase and multicomponent fluid-temperature-rock mechanics coupling analysis. In order to verify the efficiency and applicability of the program, numerical model of CO2 sequestration into underground saline reservoir in Salah is founded, and three years continuous injection of CO2 is simulated. Fluid migration and reservoir, cap rock mechanics variation underground is evaluated, and the ground surface displacement is compared with measured values by inSAR. Then a further simulation of three-dimensional cylinder injection model of CO2 sequestration in a basin of West China is done. The applicability of the coupled program TOUGHREACT-FLAC3D is demonstrated. The results under the influence of mechanics on the injection pressure as well as the displacement of ground surface are reasonable and in a good agreement with the monitoring value, and some other mechanical results are also obtained.


Zhang Y.,Jilin University | Ma X.,Jilin University | Cui H.,Jilin University | Li Y.,Jilin University | And 4 more authors.
2011 International Conference on Remote Sensing, Environment and Transportation Engineering, RSETE 2011 - Proceedings | Year: 2011

Aerobic static co-composting of agriculture organic wastes(corn straw) and organic fraction of municipal solid wastes under different ventilation rates of 0.05,0.15 and 0.2 m3 · min-1 · m -3 was studied in lab-scale for obtaining the best ventilation rate. The changes of physical and chemical properties(such as temperature, pH value, water content), nutritional factors (such as available N, available P and ratio of carbon to nitrogen), and the degree of humification (humification index and the E4/E6 value of Humic Acid) in composting material were measured to examine the feasibility of co-composting of agriculture organic wastes and organic fraction of municipal solid wastes. Results show that organic fractions of municipal solid wastes and corn straw can be used to co-composting under different ventilation rates. When the dry basis ratio of organic wastes of municipal solid wastes and corn straw was 5:1, initial water content was 55%, and the initial ratio of carbon to nitrogen was 34:1. It could not only enhance the temperature of piles and keep the high temperature for longer time, but also decrease the loss of nitrogen and accelerate the degradation of organic substance and the degree of humification at the ventilation of 0.15m3 · min-1 · m-3. It was beneficial to the accumulation of available N and available P, with the ventilation of 0.15m 3 · min-1 · m-3 better than others. © 2011 IEEE.


Chen S.,Key Laboratory of Groundwater Resources and Environment | Lu W.,Key Laboratory of Groundwater Resources and Environment | Luo J.,Key Laboratory of Groundwater Resources and Environment | Xin X.,Key Laboratory of Groundwater Resources and Environment
Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering | Year: 2012

In order to understand the effect of irrigated agriculture development on evolution of shallow groundwater system, shallow groundwater system condition of Delingshan area of Inner Mongolia in 1979 was taken as nature condition which was not strongly disturbanced by human activity. The variations of groundwater recharged and discharged in 2008 were calculated using water balance principle, and the groundwater quality was evaluated. The evolution direction and extent were analyzed by comparison of variation of shallow groundwater system input (supply item) and output (discharge item), as well as hydraulic field and chemical field under natural condition and current condition. The results show that irrigated agriculture has become the main factor of shallow groundwater evolution. The effect of irrigated agriculture on evolution hydraulic field of study area expressed in continued reduction of groundwater level and severe change of the groundwater flow field. The effect on evolution of groundwater system chemical field expressed in the change of groundwater chemical types and increase of groundwater pollution.


Wei R.C.,Key Laboratory of Groundwater Resources and Environment | Xiao C.L.,Key Laboratory of Groundwater Resources and Environment | Liang X.J.,Key Laboratory of Groundwater Resources and Environment
Advanced Materials Research | Year: 2013

The complexity of Groundwater dynamic was determined based on the fractal dimensions of groundwater depth sequence of all farms in Jiansanjiang calculated in Grassberger-Procaccia algorithm. It is showed that groundwater dynamic in Jiansanjiang is of certain complexity for fractal dimensions of all wells greater than 1. The complexity of groundwater in Jiansanjiang has a significant spatial variance structure characterized with the complexity of groundwater dynamic in the northwest lower than that in southeast, which indicates that the groundwater system in the southeast fluctuates more strongly and affected by natural and human disturbances more seriously. © (2013) Trans Tech Publications, Switzerland.


Wei R.C.,Key Laboratory of Groundwater Resources and Environment | Xiao C.L.,Key Laboratory of Groundwater Resources and Environment | Liang X.J.,Key Laboratory of Groundwater Resources and Environment
Applied Mechanics and Materials | Year: 2013

Variance analysis and variogram were used to analyze the spatial variations of eight conventional solutes, which are K++Na+, Ca2+, Mg2+, Cl-, SO4 2-, HCO3 -, NO3 -, Total hardness (TH), of 90 groundwater samples from monitoring wells that spread in the Jilin city and suburbs. It is showed that concentration distributions of groundwater solutes have significant spatial variance structure in Jilin city and suburban.. Concentration of the most groundwater solutes in urban is higher than outskirts as well as spatial variability, while the area of Jiangbei has the highest of both. Correspondingly, NO3-, Cl- and SO4 2- have greater spatial variability than other solutes. From this research a conclusion can be safely drawed, that variance analysis and variogram are effective tools to study the spatial variability of groundwater solutes. © (2013) Trans Tech Publications, Switzerland.


Wei R.-C.,Key Laboratory of Groundwater Resources and Environment | Xiao C.-L.,Key Laboratory of Groundwater Resources and Environment | Liang X.-J.,Key Laboratory of Groundwater Resources and Environment
Zhongguo Huanjing Kexue/China Environmental Science | Year: 2014

Projection pursuit method was adopted to establish groundwater pollution index model. Correspondingly, groundwater pollution indexes of monitoring wells from 1980 to 2009 were calculated. Considering the non-continuity of groundwater pollution between the both sides of Songhua River, modified local polynomial was used to complete interpolation of pollution indexes sub-regionally. Then distribution maps of groundwater pollution indexes from 1980 to 2009 showed. The results showed that, groundwater was contaminated in all districts with different severities for region-widely high groundwater pollution indexes, especially in Jiangbei district. The groundwater pollution in all districts revealed a light-severe-light character in the time revolution. Spatio-temporal evolution of groundwater pollution in this region was closely linked with human activities. From the analysis of the contributions of all pollution factors to groundwater pollution indexes in each year, a conclusion could be drawed that, nitrite, nitrate and ammonia were the main factors affecting the groundwater environment, while nitrite was the dominant one with a contribution rate of 0.7 up and down in most years.

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