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Journal of Earth Science 2025年

作者： Jiangxia Wang Panpan Xu Hui Qian Yongqi Zang Qiming Wang Zhiyuan Ma School of water and Environment， Chang'an University Key Laboratory of Subsurface Hydrology and Ecological Effects in arid Region of the Ministry of Education， Chang'an University Key Laboratory of Eco-hydrology and water Security in arid and Semi-arid Regions of Ministry of water resources， Chang'an University

The Guanzhong Basin， located in Shaanxi Province， China， has abundant geothermal resources in its hinterland. Focusing on typical thermal reservoir structural units， namely the Xianli fault-step (XL) and Xi'an depression (XA)， this study reveals the genesis of geothermal water by combining hydrochemistry and environmental isotopes. The geothermal waters of XL uniformly correspond to the Na-Cl type with high contents of major ions， while the geothermal water of XA has complex hydrochemical types. The quartz geothermometer (with maximum steam loss) and Na-K-Ca geothermometer are recommended for XL and the quartz geothermometer (with no and maximum steam loss) and Na-K geothermometer for XA. Their temperature ranges are 99-159℃ and 93-146℃， respectively. The circulation depth of geofluids in XL and XA range from 2579 to 4766 m and from 2541 to 4330 m， with mean apparent ages of 21543 and 20345 yr B.P.， respectively. The geothermal water in XL originates from a mixture of sedimentary water and ancient infiltration water， and its formation mode was the vertical heat conduction with cooling process. In contrast， the geothermal water in XA originates from the dual process of cooling and mixing， with the process being dominated by ancient infiltration water and supplementation by modern infiltration water.

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Quantitative reconstruction of salinity and precipitation changes in Central Asia over the past 3200 years using diatom and pollen records of lacustrine sediment in Aibi Lake of SW Junggar Basin

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Journal of Earth Science 2025年

作者： Long Pan Guoqiang Li Xiaoyan Wang Ming Jin Xinrong He Luo Qin Zhong Wang Wenwei Zhao Chunzhu Chen Yuanlu Liu Jin Yang Lele Shu Key Laboratory of Western China's Environmental Systems (Ministry of Education)， College of Earth and Environmental Sciences， Lanzhou University College of Earth Sciences， Chengdu University of Technology School of Geographic Science， Nantong University Key Laboratory of land Surface Process and Climate Change in Cold and arid Regions， Northwest Institute of Eco-Environment and resources， Chinese Academy of Sciences

The response of lake environments in arid Central Asia to climate change during the Late Holocene over the centennial to millennial timescales remains contentious. The reason that primarily paleoenvironmental proxies interpreting diverse and the scarcity of accurate quantitative reconstruction records. In this study， we employed diatoms and pollen records from lacustrine sediment in the Aibi Lake of SW Junggar Basin to quantitatively reconstruct salinity and watershed precipitation amounts while exploring the associated forcing mechanism. The results indicate that Aibi Lake salinity varied between 2 g/L and 47 g/L during the Late Holocene period， indicating a generally brackish environment， and corresponding to prevailing Tryblionella granulata diatom in the lake basin. Westerly-dominated annual precipitation varied between 250 mm and 320 mm during the Late Holocene period in the basin， exhibiting a generally semi-arid environment and prevailing desert steppe vegetation. The Aibi Lake has a low salinity of average value of ～15 g/L. It exhibits elevated precipitation (average value of ～280 mm) during the periods of the Roman Warm Period (2900-1990 cal yr BP)， Dark Age Cold Period (1570-1140 cal yr BP)， and Little Ice Age (590-120 cal yr BP). The reconstructed precipitation and salinity exhibit a periodicity of ～200 years， which is consistent with the cycle of phase changes of the North Atlantic Oscillation (NAO) and Total Solar Irradiance (TSI). This correlation suggests that variations in NOA and TSI significantly influence the precipitation and salinity changes in Central Asia over centennial to millennial timescales.

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Interpretable Machine Learning Method for Compressive Strength Prediction and Analysis of Pure Fly Ash-based Geopolymer Concrete

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Journal of Wuhan University of Technology(Materials Science) 2025年第1期40卷 65-78页

作者： SHI Yuqiong LI Jingyi ZHANG Yang LI Li Key Laboratory of Agricultural Soil and water Engineering in arid and Semiarid Areas of Ministry of Education Northwest A&F Uni-versityYangling 712100China College of water resources and Architectural Engineering Northwest A&F UniversityYangling 712100China Chongqing Key Laboratory of Public Big Data Security Technology Chongqing 401420China Chongqing College of Mobile Communication Chongqing 401520China Department of Civil and Environmental Engineering The Hong Kong Polytechnic UniversityHung HomKowloonHong KongChina National Rail Transit Electrification and Automation Engineering Technology Research Center(Hong Kong Branch) The Hong Kong Polytechnic UniversityKowloonHung HomHong KongChina

In order to study the characteristics of pure fly ash-based geopolymer concrete(PFGC)conveniently,we used a machine learning method that can quantify the perception of characteristics to predict its compressive *** this study,505 groups of data were collected,and a new database of compressive strength of PFGC was *** order to establish an accurate prediction model of compressive strength,five different types of machine learning networks were used for comparative *** five machine learning models all showed good compressive strength prediction performance on *** them,R2,MSE,RMSE and MAE of decision tree model(DT)are 0.99,1.58,1.25,and 0.25,*** R2,MSE,RMSE and MAE of random forest model(RF)are 0.97,5.17,2.27 and 1.38,*** two models have high prediction accuracy and outstanding generalization *** order to enhance the interpretability of model decision-making,we used importance ranking to obtain the perception of machine learning model to 13 *** 13 variables include chemical composition of fly ash(SiO_(2)/Al_(2)O_(3),Si/Al),the ratio of alkaline liquid to the binder,curing temperature,curing durations inside oven,fly ash dosage,fine aggregate dosage,coarse aggregate dosage,extra water dosage and sodium hydroxide *** temperature,specimen ages and curing durations inside oven have the greatest influence on the prediction results,indicating that curing conditions have more prominent influence on the compressive strength of PFGC than ordinary Portland cement *** importance of curing conditions of PFGC even exceeds that of the concrete mix proportion,due to the low reactivity of pure fly ash.

关键词： machine learning pure fly ash geopolymer compressive strength feature perception

Understanding the impact of mountain landscapes on water balance in the upper Heihe River watershed in northwestern China

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Journal of arid land 2013年第3期5卷 366-383页

作者： Jia QIN YongJian DING JinKui WU MingJie GAO ShuHua YI ChuanCheng ZHAO BaiSheng YE Man LI ShengXia WANG State Key Laboratory of Cryospheric Sciences Cold and Arid Regions Environmental and Engineering Research InstituteChinese Academy of Sciences division of Hydrology water-land resources in Cold and arid Regions Chinese Academy of Sciences

Estimating the impact of mountain landscape on hydrology or water balance is essential for the sus- tainable development strategies of water resources. Specifically, understanding how the change of each landscape influences hydrological components will greatly improve the predictability of hydrological responses to mountain landscape changes and thus can help the government make sounder decisions. In the paper, we used the VIC （Variable Infiltration Capacity） model to conduct hydrological modeling in the upper Heihe River watershed, along with a frozen-soil module and a glacier melting module to improve the simulation. The improved model performed satisfactorily. We concluded that there are differences in the runoff generation of mountain landscape both in space and time. About 50% of the total runoff at the catchment outlet were generated in mid-mountain zone （2,900-4,000 m asl）, and water was mainly consumed in low mountain region （1,700-2,900 m asl） because of the higher requirements of trees and grasses. The runoff coefficient was 0.37 in the upper Heihe River watershed. Barren landscape produced the largest runoff yields （52.46% of the total runoff） in the upper Heihe River watershed, fol- lowed by grassland （34.15%）, shrub （9.02%）, glacier （3.57%）, and forest （0.49%）. In order to simulate the impact of landscape change on hydrological components, three landscape change scenarios were designed in the study. Scenario 1, 2 and 3 were to convert all shady slope landscapes at 2,000-3,300 m, 2,000-3,700 m, and 2,000-4,000 m asl respectively to forest lands, with forest coverage rate increased to 12.4%, 28.5% and 42.0%, respectively. The runoff at the catchment outlet correspondingly declined by 3.5%, 13.1% and 24.2% under the three scenarios. The forest landscape is very important in water conservation as it reduced the flood peak and increased the base flow. The mountains as ＂water towers＂ play important roles in water resources generation and the impact of mountai

关键词： mountain landscape runoff modeling water balance VIC model Heihe River watershed

Direct numerical simulation of matrix diffusion across fracture/matrix interface

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water Science and Engineering 2013年第4期6卷 365-379页

作者： Yong ZHANG Eric M.LABOLLE Donald M.REEVES Charles RUSSELL division of Hydrologic Sciences Desert Research Institute Department of land Airand Water ResourcesUniversity of California

Accurate descriptions of matrix diffusion across the fracture/matrix interface are critical to assessing contaminant migration in fractured media. The classical transfer probability method is only applicable for relatively large diffusion coefficients and small fracture spacings, due to an intrinsic assumption of an equilibrium concentration profile in the matrix blocks. Motivated and required by practical applications, we propose a direct numerical simulation （DNS） approach without any empirical assumptions. A three-step Lagrangian algorithm was developed and validated to directly track the particle dynamics across the fracture/matrix interface, where particle＇s diffusive displacement across the discontinuity is controlled by an analytical, one-side reflection probability. Numerical experiments show that the DNS approach is especially efficient for small diffusion coefficients and large fracture spacings, alleviating limitations of the classical modeling approach.

关键词： Key words: fracture matrix interface direct numerical simulation transfer probability Lagrangian algorithm

The shifts of precipitation phases and their impacts

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Science China Earth Sciences 2025年

作者： Xuemei LI Tao CHE Yuanlong TANG Huan'e DUAN Guigang WANG Xu ZHANG Chuanming YANG Jun WU Yue ZHANG Lanhai LI Faculty of Geomatics Lanzhou Jiaotong University National-Local Joint Engineering Research Center of Technologies and Applications for National Geographic State Monitoring Key Laboratory of Science and Technology in Surveying & Mapping Gansu Province Key Laboratory of Cryospheric Science and Frozen Soil Engineering Heihe Remote Sensing Experimental Research StationNorthwest Institute of Eco-Environment and Resources Chinese Academy of Sciences Xinjiang Key Laboratory of water Cycle and Utilization in arid Zone Xinjiang Institute of Ecology and Geography Chinese academy of Sciences Tianshan Snow Cover and Avalanche Observation and Research Station of Xinjiang

Precipitation comes in various phases, including rainfall, snowfall, sleet, and hail. Shifts of precipitation phases, as well as changes in precipitation amount, intensity, and frequency, have significant impacts on regional climate, hydrology,ecology, and the energy balance of the land-atmosphere system. Over the past century, certain progress has been achieved in aspects such as the observation, discrimination, transformation, and impact of precipitation phases. Mainly including:since the1980s, studies on the observation, formation mechanism, and prediction of precipitation phases have gradually received greater attention and reached a certain scale. The estimation of different precipitation phases using new detection theories and methods has become a research focus. Avariety of discrimination methods or schemes, such as the potential thickness threshold method of the air layer, the temperature threshold method of the characteristic layer, and the near-surface air temperature threshold method,have emerged one after another. Meanwhile, comparative studies on the discrimination accuracy and applicability assessment of multiple methods or schemes have also been carried out simultaneously. In recent years, the shift of precipitation from solid to liquid (SPSL) in the mid-to-high latitudes of the Northern Hemisphere has become more pronounced due to global warming and human activities. It leads to an increase in rain-on-snow (ROS) events and avalanche disasters, affecting the speed, intensity, and duration of spring snow-melting, accelerating sea ice and glacier melting, releasing carbon from permafrost, altering soil moisture, productivity, and phenological characteristics of ecosystems, and thereby affecting their structures, processes, qualities, and service functions. Although some progress has been made in the study of precipitation phases, there remains considerable research potential in terms of completeness of basic data, reliability of discrimination schemes,

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Dynamics and hotspots of soil erosion and management scenarios of the Central Rift Valley of Ethiopia

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International Journal of Sediment Research 2012年第1期27卷 84-99页

作者： Derege Tsegaye MESHESHA Atsushi TSUNEKAWA Mitsuru TSUBO Nigussie HAREGEWEYN arid land Research Center Tottori University Department of land resources Management and Environmental Protection Mekelle University

Most of the lowland in the central rift valley of Ethiopia is arid or semiarid and in degradation,with frequent occurrence of *** erosion by water during the rainy season is a serious problem in the region,leading to declining agricultural production,decreased food security,and a sedimentation risk for water ***,there has been no systematic study of this problem or of possible management *** meet this need,we analyzed soil erosion rates from 1973 to 2006, identified erosion hotspots,and proposed possible soil conservation *** assessed the soil loss dynamicity using the universal soil-loss equation and geographical information system software, considering the land use change at the following three periods:1973,1985 and *** characterized the watershed in terms of the erosion severity,topography,and land use to identify hotspots and proposed,modeled,and evaluated various watershed management scenarios to mitigate the *** erosion increased markedly from 1973 to 2006,with annual rates of 31,38,and 56 t ha"1 in 1973,1985,and 2006,respectively,as a result of vegetation degradation and particularly the conversion of thousands of hectares of forest or woodland into *** observed soil erosion rates are far from the tolerable rate of soil loss of the country and hence require urgent soil conservation interventions,especially in the hotspot *** proposed eight scenarios for reducing soil losses and evaluated their *** degraded land（using exclosures and planted vegetation） and installing stone erosion-control structures（stone bund） in cropland reduced the total soil loss by 12.6%and 63.8%,*** hotspot areas with annual soil loss of more than 20 t ha;by integrated management（erosion-control structures and exclosures） was the most effective approach,reducing soil loss by 87.8%.

关键词： Environmental rehabilitation Ethiopia land degradation Soil conservation Soil erosion USLE model

Role of Ca^(2+) on Growth of Brassica campestris *** ***(L.) Czern & Coss under Na^+ Stress

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Journal of Integrative Plant Biology 2010年第6期52卷 549-555页

作者： Badr-uz-Zaman M.Salim Rehana Asghar land resources Research Programme Institute of Natural Resources and Environmental SciencesNational Agricultural Research Centre Department of Botany University of Arid Agriculture

Root and shoot growth of Brassica campestris L. and B. juncea increased significantly （P 〈 0.01） with enhanced Ca2＋ treatment along with 60 mM NaCl in the root medium. The maximum fresh mass of shoot and root in *** was recorded at 10 mM Ca2＋ concentration. The relative growth rate of shoot of both species reached its maximum at 8 mM of Ca2＋ concentration. Average rate of Ca2＋ intake （lCa） was higher in B. juncea than 6. campestris. In B. juncea, the average transport of Ca2＋ to shoot increased by 19%, 38%, 119%, 125% and 169% compared with the control. Furthermore specific utilization rate of Ca2＋ was higher in B. juncea than B. campestris. In B. campestris it increased by 9%, 32%, 41% and 59% at 4, 6, 8, and 10 mM of calcium in comparison to 2 mM Ca2＋ treatment. At 4, 6, 8 and 10 mM of Ca2＋ application, the increase in the leaf area ratio was 10,17, 23 and 30%, respectively. In the shoot and root portions of B. campestris and ***, Ca2＋ had a linear relationship with potassium and sulfur, whereas it was in antagonism with sodium ion.

关键词： Coss under Na Czern Stress

Estimation of infiltration models parameters and their comparison to simulate the onsite soil infiltration characteristics

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International Journal of Agricultural and Biological Engineering 2019年第3期12卷 84-91页

作者： Hafiz Umar Farid Zahid Mahmood-Khan Ijaz Ahmad Aamir Shakoor Muhammad Naveed Anjum Muhammad Mazhar Iqbal Muhammad Mubeen Muhammad Asghar Department of Agricultural Engineering Bahauddin Zakariya UniversityMultan-Pakistan Center of Excellence in water resources Engineering(CEWRE) University of Engineering and TechnologyLahore-Pakistan division of Hydrology water-land resources in Cold and arid Regions Cold and Arid Region Environmental and Engineering InstituteChinese Academy of SciencesLanzhou 730000China Graduate School of water resources Sungkyunkwan UniversitySuwon-si 2066Korea Department of Environmental Sciences COMSATS Institute of Information TechnologyVehari-Pakistan

Detailed knowledge about soil characteristics and site-specific final steady infiltration rate could help to increase the irrigation water use efficiency and decrease water losses in agricultural *** experiments were conducted on Agricultural Research Farm of Bahauddin Zakariya University,Multan,Pakistan during *** cumulative infiltration depth was measured using double ring infiltrometer at selected six points of the study *** commonly used infiltration models such as Kostikov’s,Philip’s and Horton’s were fitted to the field infiltration data for determination of model parameters and to find the best fit model for the study ***’s infiltration model’s parameters such as empirical constant‘c’and infiltration decay constants‘k’were obtained in the ranges of 0.140-0.290 and 0.307-0.433,***’s infiltration model’s parameters such as sorptivity‘S’and conductivity constant‘A’were found in the ranges of 0.167-0.288 cm/min1/2 and-0.001 to-0.009 cm/min,***,the Horton’s model’s‘parameter‘k’was obtained in the range of-1.619 *** value of infiltration capacity at onset of infiltration(fo)was obtained as 1.744 to 3.491 for all the six *** analysis showed that the infiltration models using the estimated parameters have satisfactory prediction capability at all the selected ***’s model provided the lowest mean values for RMSE(0.235)and highest mean values for ME(94%);and the lowest mean values for MPD(0.127).This indicated that infiltration can be well-described by the Horton’s model at the selected site.

关键词： infiltration characteristics infiltration models parameters estimation perdition capability

Early Holocene environment at a key location of the northwest boundary of the Asian summer monsoon: a synthesis on chronologies of Zhuye Lake, Northwest China

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Journal of arid land 2014年第5期6卷 511-528页

作者： Yu LI NaiAng WANG ChengQi ZHANG Yue WANG Center for Hydrologic Cycle and water resources in arid Region College of Earth and Environmental Sciences Lanzhou University

The intensified monsoon increases summer rainfall and creates wet conditions in the Asian summer monsoon region during the early Holocene. Along with millennial-scale changes of the monsoon intensity, it is still unclear whether the boundary of the monsoon region changes according to monsoon variability. Investigations into the early Holocene environment in monsoon marginal zones are crucial for understanding the monsoon boundary changes. Zhuye Lake is located at the northwest edge of the Asian summer monsoon, the northern Qilian Mountains, which are less affected by modern summer monsoon water vapor. Previous studies have reached different conclusions regarding the early Holocene climatic and environmental changes based on different dating methods（^14C and OSL（optically stimulated luminescence）） and materials（shells, carbonate, pollen concentrates and bulk organic carbon）. In this study, we synthesized 102 ^14C dates and 35 OSL dates from ten Holocene sedimentary sections and ten paleo-shorelines in the lake basin. A comparison between ages from different dating methods and materials generally shows that carbon reservoir effects are relatively slight in Zhuye Lake while the disordered chronologies are mainly related to the erosion processes and reworking effects. In addition, proxy data, including lithology, pollen, total organic carbon and carbonate, were collected from different sites of Zhuye Lake. According to the new synthesis, the early Holocene environment was relatively humid, associated with high runoff and lake water levels. The result indicates that the monsoon boundary moves to the north during the period of the intensified monsoon. A typical arid-area lake was formed during the mid-Holocene when carbonate accumulation and high organic matter contents were the main features of this period. The lake retreated strongly during the late Holocene, showing a drought trend. Overall, the lake evolution is generally consistent with the Holocene Asian summer mons

关键词： the early Holocene ^14C dating OSL dating lacustrine sediments Asian summer monsoon monsoon marginal zones