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Mapping Soil Salinity Using a Similarity-based Prediction Approach:A Case Study in Huanghe River Delta,China

Chinese Geographical Science 2015年第3期25卷 283-294页

作者： YANG Lin HUANG Chong LIU Gaohuan LIU Jing ZHU A-Xing State Key Laboratory of Resources and Environment Information System Institute of Geographical Sciences and Natural Resources ResearchChinese Academy of Sciences Department of geography University of Wisconsin-Madison Jiangsu Center for Collaborative Innovation in Geographical Information Resource development and Application and school of geography Nanjing Normal University

Spatial distribution of soil salinity can be estimated based on its environmental factors because soil salinity is strongly affected and indicated by environmental factors. Different with other properties such as soil texture, soil salinity varies with short-term time. Thus, how to choose powerful environmental predictors is especially important for soil salinity. This paper presents a similarity-based prediction approach to map soil salinity and detects powerful environmental predictors for the Huanghe(Yellow) River Delta area in China. The similarity-based approach predicts the soil salinities of unsampled locations based on the environmental similarity between unsampled and sampled locations. A dataset of 92 points with salt data at depth of 30–40 cm was divided into two subsets for prediction and validation. Topographical parameters, soil textures, distances to irrigation channels and to the coastline, land surface temperature from Moderate Resolution Imaging Spectroradiometer(MODIS), Normalized Difference Vegetation Indices(NDVIs) and land surface reflectance data from Landsat Thematic Mapper(TM) imagery were generated. The similarity-based prediction approach was applied on several combinations of different environmental factors. Based on three evaluation indices including the correlation coefficient(CC) between observed and predicted values, the mean absolute error and the root mean squared error we found that elevation, distance to irrigation channels, soil texture, night land surface temperature, NDVI, and land surface reflectance Band 5 are the optimal combination for mapping soil salinity at the 30–40 cm depth in the study area(with a CC value of 0.69 and a root mean squared error value of 0.38). Our results indicated that the similarity-based prediction approach could be a vital alternative to other methods for mapping soil salinity, especially for area with limited observation data and could be used to monitor soil salinity distributions in the future.

关键词： soil salinization similarity-based prediction approach digital soil mapping Huanghe (Yellow) River Delta environmental factor

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Changes in groundwater levels and the response of natural vegetation to transfer of water to the lower reaches of the Tarim River

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Journal of Environmental Sciences 2007年第10期19卷 1199-1207页

作者： XU Hai-liang YE Mao LI Ji-mei Xinfiang Institute of Ecology and geography Research Chinese Academic of Science Urumqi 830011 China school of geography Sciences and Touristy Xinfiang Normal University Urumqi 830054 China

Restoration and reconstruction of the degraded Tarim River ecosystem is an important challenge. A goal of an ecological water conveyance project is to protect and restore the natural vegetation in the lower reaches of Tadm River by transferring water from Bosten Lake, through the river channel, to the lower reaches. This study describes the changes in groundwater depth during the water transfer and the respondence of riparian vegetation to alterations in groundwater levels. The results indicate that groundwater depth along the Tarim River channel has a significant spatial-temporal component. Groundwater levels closest to the river channel show the most immediate and pronounced changes as a response to water transfer while those further away respond more slowly, although the observed change appears to be longer in duration. With a rise in the groundwater level, natural vegetation responded with higher growth rates, biomass and biodiversity. These favorable changes show that it is feasible to protect and restore the degraded natural vegetation by raising the groundwater depth. Plant communities are likely to reflect the hysteresis phenomenon, requiting higher water levels to initiate and stimulate desired growth than what may be needed to maintain the plant community. Because different species have different ecologies, including different root depths and densities and water needs, their response to increasing water availability will be spatially and temporally heterogenous. The response of vegetation is also influenced by microtopography and watering style. This paper discusses strategies for the protection and restoration of the degraded vegetation in the lower reaches of the Tarim River and provides information to complement ongoing theoretical research into ecological restoration in add or semi-arid ecosystems.

关键词： the lower reaches of Tarim River ecological watering conveyance groundwater depth ecological response natural vegetation

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Multi-model ensemble learning for battery state-of-health estimation:Recent advances and perspectives

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Journal of Energy Chemistry 2025年第1期100卷 739-759页

作者： Chuanping Lin Jun Xu Delong Jiang Jiayang Hou Ying Liang Zhongyue Zou Xuesong Mei State Key Laboratory for Manufacturing Systems Engineering Xi'an Jiaotong University Shaanxi Key Laboratory of Intelligent Robots School of Mechanical Engineering Xi'an Jiaotong University Department of Electrical Engineering and Automation Luoyang Institute of Science and Technology school of Mechanical Engineering Hangzhou Dianzi University

The burgeoning market for lithium-ion batteries has stimulated a growing need for more reliable battery performance monitoring. Accurate state-of-health(SOH) estimation is critical for ensuring battery operational performance. Despite numerous data-driven methods reported in existing research for battery SOH estimation, these methods often exhibit inconsistent performance across different application scenarios. To address this issue and overcome the performance limitations of individual data-driven models,integrating multiple models for SOH estimation has received considerable attention. Ensemble learning(EL) typically leverages the strengths of multiple base models to achieve more robust and accurate outputs. However, the lack of a clear review of current research hinders the further development of ensemble methods in SOH estimation. Therefore, this paper comprehensively reviews multi-model ensemble learning methods for battery SOH estimation. First, existing ensemble methods are systematically categorized into 6 classes based on their combination strategies. Different realizations and underlying connections are meticulously analyzed for each category of EL methods, highlighting distinctions, innovations, and typical applications. Subsequently, these ensemble methods are comprehensively compared in terms of base models, combination strategies, and publication trends. Evaluations across 6 dimensions underscore the outstanding performance of stacking-based ensemble methods. Following this, these ensemble methods are further inspected from the perspectives of weighted ensemble and diversity, aiming to inspire potential approaches for enhancing ensemble performance. Moreover, addressing challenges such as base model selection, measuring model robustness and uncertainty, and interpretability of ensemble models in practical applications is emphasized. Finally, future research prospects are outlined, specifically noting that deep learning ensemble is poised to advance ens

关键词： Lithium-ion battery State-of-health estimation Data-driven Machine learning Ensemble learning Ensemble diversity

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Rural vulnerability in China:Evaluation theory and spatial patterns

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Journal of Geographical Sciences 2021年第10期31卷 1507-1528页

作者： YANG Ren PAN Yuxin school of geography and Planning Sun Yat-sen UniversityGuangzhou 510275China China Regional Coordinated development and Rural Construction Institute Sun Yat-sen UniversityGuangzhou 510275China

An indicator system is constructed and applied for comprehensive measurement of rural vulnerability in China’s *** the selection of five representative transects we explore regional differences in,and driving forces of,China’s rural *** results show that(1)The rural vulnerability of counties in China is generally within the threshold range of low to medium,and exhibits obvious spatial *** the"Bole-Taipei Line",there is a spatial pattern of north-south *** in the northeast part of the counties have low vulnerability,while those in the southwest are relatively vulnerable(2)External environmental phenomena are the leading factors that induce rural ***,the rural ecological subsystem composed of ecological exposure,ecological sensitivity,and ecological adaptation is the principal determinant of rural *** rural economic subsystem composed of economic exposure,economic sensitivity,and economic adaptation is also a core determinant of rural *** social subsystem composed of social exposure,social sensitivity,and social adaptation is also an important determinant of rural vulnerability.(3)According to the principle of adapting measures to local conditions,different regions should seek to reduce regional embeddedness and path *** should strengthen the prediction and monitoring of sources of disturbance in rural areas,and scientifically control the sensitivity of the system *** the adaptive capacity of the rural system can be improved pursuant of promoting sustainable development.

关键词： rural vulnerability rural regional system rural sustainable development rural revitalization rural geography China

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Two centuries of April-July temperature change in southeastern China and its influence on grain productivity

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Science Bulletin 2017年第1期62卷 40-45页

作者： Jiangfeng Shi Jinbao Li David D.Zhang Jingyun Zheng Shiyuan Shi Quansheng Ge Harry F.Lee Yesi Zhao Jie Zhang Huayu Lu Ministry of Education Key Laboratory for Coast and Island development School of Geographic and Oceanographic Sciences Nanjing University Department of geography University of Hong Kong Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences

China is a traditional agriculture based country and one main region for crop production is southeastern China where temperature is a dominant climate variable affecting agriculture. Temperature and social disturbances both influence crop production, yet distinguishing their relative impacts is difficult due to a lack of reliable, high-resolution historical climatic records before the very recent period. Here we present the first tree-ring based warm-season temperature reconstruction for southeastern China, a core region of the East Asian monsoon, for the past 227 years. The reconstruction target was April-July mean temperature, and our model explained 60.6% of the observed temperature variance during 1953–*** correlation analysis showed that the reconstruction is representative of April-July temperature change over most of eastern China. The reconstructed temperature series agrees well with China-scale(heavily weighted in eastern China) agricultural production index values quite well at decadal *** impacts of social upheavals on food production, such as those in the period 1920–1949, were confirmed after climatic influences were excluded. Our study should help distinguish the influence of social disturbance and warm-season temperature on grain productivity in the core agricultural region of China during the past two centuries.

关键词： Temperature Grain productivity Social disturbance China Tree-rings

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Soil Environmental Index For Slovak Agricultural Land

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Pedosphere 2014年第1期24卷 137-144页

作者： J.VILCEK R.BUJNOVSKY Department of geography and Regional development Faculty of Humanities and Natural SciencesUniversity of Presov Soil Science and Conservation Research Institute

The soil environmental index(SEI),which is a four digit code system,represents relatively homogenous spatial unit with specific soil capacity to provide ecological or non-production *** work aimed to present information on rating and economic evaluation of SEI,which is a spatial identifier used for expressing heterogeneity of Slovak agricultural soil to support analysis of soil ecological *** this study,SEI index expressed the capacity of soil to accumulate water,immobilise the risk elements and substances and transform risk substances(organic pollutants).Partial evaluations of soil capacity to provide above mentioned functions were used to derive final SEI *** the agricultural soils of Slovakia there were 493 combinations of soil environmental *** index was expressed through rating(point)value and economic *** value of Slovak agricultural land to provide selected ecological soil functions was 55.3 points,which corresponded to 35.946 billionper agricultural land or approximately 1.42per square *** identification of SEI codes and relevant database were developed in vector form via geographical information systems of Soil Science and Conservation Research Institute,*** addition to using the national soil database system,a strategy was presented for evaluating and pricing of soil ecological function,and the development of an soil environmental *** and evaluation of vitally important soil functions expressed by SEI can significantly contribute to planning and protection of the soil,and can regulate indiscriminate anthropic interventions in land use decisions.

关键词： ecological soil functions environmental potential soil evaluation

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Relationships Between Intensity Gradation and Evolution of Soil Erosion: A Case Study of Changting in Fujian Province, China

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Pedosphere 2012年第2期22卷 243-253页

作者： LIN Chen ZHOU Sheng-Lu WU Shao-Hua LIAO Fu-Qiang school of Geographic and Oceanographic Sciences Nanjing UniversityNanjing 210093(China) State Key Laboratory of Soil and sustainable Agriculture Institute of Soil ScienceChinese Academy of SciencesNanjing 210008(China) school of geography and Environment Jiangxi Normal UniversityNanchang 330022(China)

Soil erosion gradation is a robust and objective quantitative indicator of soil erosion intensity. Recent applications of soil erosion gradation have focused on monitoring soil erosion with models or simulation of soil erosion through gradation trends. However, soil erosion simulation accuracy is generally being reduced due to the rare consideration of the relationship between soil erosion gradation and erosion evolution. In this study, we investigated different soil erosion intensity grades to demonstrate their sensitivity to types and rates of erosion. Specifically, the objective was to define the relationship between soil erosion gradation and soil erosion evolution in Changting, an undeveloped area in Fujian Province, China, for four time intervals (1975, 1990, 1999, and 2006). The time series of erosion gradation were developed by modeling analysis with integration of several erosion indicators, and the relationships between the erosion grades and evolution types and rates were quantified. Comparison of the collapsing forces with natural and restoring forces based on human activity demonstrated that there existed an obvious spatial uncertainty in the erosion evolution types, both positive and negative succession coexisted, and the evolution rates were mostly influenced by the force of policy orientation. The impacts of these driving forces were eventually reflected in the erosion intensity gradation and erosion evolution. The correlation between the negative succession rate and erosion intensity gradation was weak and showed a poor contribution to the average succession rate, while the negative correlation between the positive succession rate and erosion intensity gradation would be increasingly clear as time passed.

关键词： driving forces negative succession policy orientation positive succession time series

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Evolution of Jobs-housing Spatial Relationship in Beijing Metropolitan Area:A Job Accessibility Perspective

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Chinese Geographical Science 2015年第3期25卷 375-388页

作者： HAN Huiran YANG Chengfeng WANG Enru SONG Jinping ZHANG Meng school of geography Beijing Normal University Department of geography University of North Dakota Faculty of Hospitality and Tourism Management Macao University of Science and Technology

With the urban expansion and economic restructuring, the jobs-housing relationship has become an important issue in studies on urban spatial structure. This paper employed a job accessibility model, which is an evaluation instrument to measure the jobs-housing relationship in Beijing Metropolitan Area from a job accessibility perspective. The results indicate that the population in the central city is declining, whereas the population in the suburbs is consistently growing and forming new population centers. However, the distribution pattern of employment is still highly centralized. Job accessibility varies in different locations, but the inner-city areas(within the Third Ring road) have seen improved job accessibility over time while job accessibility in the suburbs(especially outside the Fourth Ring road) has decreased, and this has led it to become a primary area of residential and employment mismatch. At the same time, the new towns in the outer suburbs have not yet demonstrated great potential to attract more jobs. In addition we find that, to some extent, urban planning changes the jobs-housing relationship, but a polycentric urban spatial structure is not yet evident. The floating population and related housing policy also affect the jobs-housing relationship. We propose some measures to resolve the spatial mismatch as well as some future research directions.

关键词： jobs-housing relationship job accessibility spatial mismatch population density employment density Beijing Metropoli-tan Area

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The higher grain production, the more social deprivation? A case study of Henan province in traditional agricultural areas of China

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Journal of Mountain Science 2018年第1期15卷 167-180页

作者： GAO Jun-bo QIAO Wei-feng LIU Yan-sui LI Yu-rui TU Wei ZHANG Yong-xian Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences school of geography Science Xinyang Normal University school of geography Science Nanjing Normal University Department of Geology & geography Georgia Southern University Institute of Surveying And Mapping Information Engineering University

This paper examines the spatial-temporal dynamics of inequality from the perspective of social deprivation in the context of continuous growth of grain production using national census data from 2000 and 2010 for Henan province,*** analytical results show an overall level of social deprivation that is high and a widening social deprivation gap at the county *** social deprivation shows great spatiotemporal heterogeneity,the higher deprived counties are mainly distributed in central and eastern Henan province,while counties with lower social deprivation are clustered in northwestern regions,formed a belt-shape spatial differential between the south(higher deprived counties clustered)and northwest(low deprived counties clustered)Henan in 2000,and changed toward a core-periphery semi annular spatial structure in 2010,the low deprived counties surrounded by high deprived *** social deprivation shows a"west low and east high"spatial pattern,similar to the grain production in Henan *** development level was low in most counties in Yudong plain despite of keeping the continuous increase of grain production,meaning the higher grain output did not result in the more social development expected in Chinese traditional agricultural areas,and the regional disparity is expected to increase in the near future if development conditions are not changed,which could inspire more targeted rural governance options.

关键词： Spatial-temporal change Grain production Social inequality Social deprivation Henan province

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First principles study on d^0 half-metallic properties of full-Heusler compounds RbCaX_2(X=C,N,and O)

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Chinese Physics B 2015年第6期24卷 494-499页

作者：高永春王啸天 Habib Rozale Department of Physics College of ScienceHebei United University school of Material Sciences and Engineering Hebei University of Technology Condensed Matter and sustainable development Laboratory Physics DepartmentUniversity of Sidi-Bel-Abbe's

A first-principles approach is employed to study the structural, electronic, and magnetic properties of RbCaX2 （X = C, N, and O） full-Heusler compounds. It is observed that RbCaN2 and RbCaO2 are new do half-metals with an integer magnetic moment of 3 μB and 1 μB in their ferrimagnetic ground states, respectively, while RbCaC2 is a common metallic compound. Analysis of the density of states of these compounds indicates that the magnetic moment and furthermore, the half-metallicity primarily originate from the spin-polarization of the p-like states of N and O atoms. The half-metallic （HM） gaps of RbCaN2 and RbCaO2 are notably large; thus, the half-metallicity is robust against lattice distortion. Such materials are suitable to be grown on various semiconductor substrates. In addition, for RbCaN2 and RbCaO2, four possible terminations of the surface are also calculated.

关键词： d0 half-metallicity electronic structure full-Heusler compound

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