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Fusing multi-source data to map spatio-temporal dynamics of winter rape on the Jianghan Plain and Dongting Lake Plain, China

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Journal of Integrative Agriculture 2019年第10期18卷 2393-2407页

作者： TAO Jian-bin LIU Wen-bin TAN Wen-xia KONG Xiang-bing XU Meng key laboratory for geographical process analysis & simulation of hubei province/School of urban and environmental sciences Central China Normal UniversityWuhan 430079P.R.China key laboratory of the Loess Plateau Soil Erosion and Water Loss process and Control Ministry of Water Resources/Yellow River Institute of Hydraulic ResearchZhengzhou 450003P.R.China

Mapping crop distribution with remote sensing data is of great importance for agricultural production, food security and agricultural sustainability. Winter rape is an important oil crop, which plays an important role in the cooking oil market of China. The Jianghan Plain and Dongting Lake Plain (JPDLP) are major agricultural production areas in China. Essential changes in winter rape distribution have taken place in this area during the 21st century. However, the pattern of these changes remains unknown. In this study, the spatial and temporal dynamics of winter rape from 2000 to 2017 on the JPDLP were analyzed. An artificial neural network (ANN)-based classification method was proposed to map fractional winter rape distribution by fusing moderate resolution imaging spectrometer (MODIS) data and high-resolution imagery. The results are as follows:(1) The total winter rape acreages on the JPDLP dropped significantly, especially on the Jianghan Plain with a decline of about 45% during 2000 and 2017.(2) The winter rape abundance keeps changing with about 20–30% croplands changing their abundance drastically in every two consecutive observation years.(3) The winter rape has obvious regional differentiation for the trend of its change at the county level, and the decreasing trend was observed more strongly in the traditionally dominant agricultural counties.

关键词： winter rape,spatio-temporal dynamics,time-series MODIS data artificial neural network

Change features of time-series climate variables from 1962 to 2016 in Inner Mongolia,China

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Journal of Arid Land 2020年第1期12卷 58-72页

作者： XU Lili YU Guangming ZHANG Wenjie TU Zhenfa TAN Wenxia key laboratory for geographical process analysis&simulation of hubei province Central China Normal UniversityWuhan 430079China college of urban and environmental sciences Central China Normal UniversityWuhan 430079China State key laboratory of Resources and environmental Information System Institute of Geographic Sciences and Natural Resources ResearchBeijing 100101China Plant Functional Biology and Climate Change Cluster(C3) University of Technology SydneyNSW 2007Australia

Detecting change features of climate variables in arid/semi-arid areas is essential for understanding related climate change patterns and the driving and evolution mechanism between climate and arid/semi-arid *** paper takes Inner Mongolia of China,a unique arid/semi-arid ecosystem,as the study *** first detected trend features of climate variables using the linear trend analysis method and then detected their trend-shift features using the breaks for additive seasonal and trend method based on the time-series of monthly precipitation and monthly mean temperature datasets from 1962 to *** analyzed the different change features of precipitation and temperature on a regional scale and in different ecological zones to discover the spatial heterogeneity of change *** results showed that Inner Mongolia has become warmer-wetter during the past 54 *** regional annual mean temperature increased 0.4°C per decade with a change rate of 56.2%.The regional annual precipitation increased 0.07 mm per decade with a slightly change rate of about 1.7%,but the trend was not statistically *** warmer trend was contributed by the same positive trend in each season,while the wetter trend was contributed by the negative trend of the summer precipitation and the positive trend of the other three *** regional monthly precipitation series had a trend-shift pattern with a structural breakpoint in the year 1999,while the regional monthly mean temperature series showed an increasing trend without a periodical *** the year 2000,the warmer-wetter trend of the climate in Inner Mongolia was *** late 20th century was a key period,because the acceleration of the wetter trend in some local zones(I and II)and the alleviation of the warmer trend in some local zones(Ⅶ,Ⅷand IX)occurred ***,the change features had a strong spatial heterogeneity,the southeastern and southwestern of Inner Mongolia went through

关键词： temperature precipitation trend feature trend-shift feature arid/semi-arid area

Influences of rock fragments on the hydraulics and erosion of concentrated runoff in steep spoil heaps on the Loess Plateau of China

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International Journal of Sediment Research 2022年第5期37卷 553-562页

作者： Wenzhao Guo Hongliang Kang Xiao Yu Wenlong Wang Pei Tian State key laboratory of Soil Erosion and Dryland Farming on the Loess Plateau Institute of Water and Soil Conservation Northwest Agriculture & Forestry University key laboratory for geographical process analysis & simulation of hubei province Central China Normal University

The soil-rock mixed spoil heaps are prone to severe soil erosion during heavy rain, causing severe land degradation and ecological and environmental damage. Nevertheless, past research on the erosion on spoil heaps has focused on soil particles that were readily eroded and disregarded the rock fragments(RF) that were not readily eroded. To explore the effect of the RF embedded in spoil heaps on the hydraulics of and erosion caused by concentrated runoff, scour-erosion experiments were implemented on three types of spoil heaps: RF = 7%, RF = 45%, and RF = 69%. The RF clearly reduced runoff and erosion on steep spoil heaps. As the RF increased from 7% to 69%, the runoff intensity and runoff coefficient decreased by 72.9%-79.1% and 83.2%-84.1% respectively, and the sediment concentration, soil denudation rate, and total soil loss decreased by 36.0%-47.8%, 83.7%-87.1%, and 87.0%-92.3%, *** rills were generated during the experiments, and the RF distinctly influenced the rill characteristics. High contents of RF restrained rill retreating and undercutting, and promoted rill widening. With an increase in RF, the flow shear stress and stream power gradually decreased, and the Darcy-Weisbach roughness coefficient increased. These findings imply that the RF dissipated the flow energy and reduced soil detachment capacity and sediment transport capacity. Soil detachment is strongly related to the Darcy-Weisbach roughness coefficient, Reynolds number, and runoff intensity,which may be the preferred descriptors of soil detachment. The current findings indicate that embedded rock fragments could effectively reduce soil loss on steep spoil heaps.

关键词： Soil erosion Runoff Rock fragments (RF) Rills Chinese loess plateau

Unique landslides (loess slide-flows) induced by an extreme rainstorm in 2018 on the Loess Plateau: A new geological hazard and erosion process

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International Journal of Sediment Research 2023年第2期38卷 228-239页

作者： Li Luo Wen-Zhao Guo Pei Tian Yi-li Liu Shao-Kun Wang Jia-Wei Luo State key laboratory of Soil Erosion and Dryland Farming on the Loess Plateau/college of Water Resources and Architectural Engineering Northwest Agriculture and Forestry University State key laboratory of Geohazard Prevention and Geoenvironment Protection Chengdu University of Technology key laboratory for geographical process analysis & simulation of hubei province Central China Normal University

Currently, the vegetation has recovered well in most areas of the Loess Plateau in China, and soil erosion has significantly decreased. However, the heavy rainfall event in July 2018 triggered many instances of a unique type of loess landslides(i.e., slide-flows) on the gully-slopes with vegetation recovery in the Nanxiaohegou Basin on the Loess Plateau. This rainfall event was unusual and was a persistent heavy rainfall. The accumulated rainfall from 24 June to 10 July was 232.2 mm, which comprised 42% of the mean annual rainfall. A loess slide-flow is characterized by combining two movement types of the slide and flow. The loess slide-flows first slide on the gully-slopes and then turn into long run-out earthflows moving downstream, delivering vast amounts of sediment to the river. The average landslide erosion rates were 110.8-134.9 kg/m2. These loess slide-flows generally did not occur individually but in groups,which were characterized by large numbers, high density, small scale, and shallow depth. The changes of vegetation characteristics and soil characteristics both had a significant impact on the scale of the landslides. Grass with high coverage had an adverse effect on the occurrence of shallow landslides. The adverse hydrological effects of the plant may offset the weak root reinforcement. Loess slide-flows have become a new geological hazard and erosion process on the Loess Plateau. Loess slide-flows are a prominent ecological and environmental problem after vegetation restoration, and more attention should be paid to loess slide-flows in the future.

关键词： Loess plateau Landslide Soil erosion Vegetation Rainfall

Dynamic transfer and driving mechanisms of the coupling and coordination of agricultural resilience and rural land use efficiency in China

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Journal of geographical sciences 2024年第8期34卷 1589-1614页

作者： CHEN Xiaohong AN Yongle PAN Wei WANG Ying CHEN Lintao GU Yue LIU Haihan YANG Fan college of Geography Science Harbin Normal UniversityHarbin 150025China Harbin urban and Rural Planning&Design Institute Harbin 150010China

The joint study of agriculture and rural areas is of great significance for safeguarding agricultural development,revitalizing rural areas,and enhancing farmers'*** paper aims to assess the spatiotemporal evolution characteristics of the coupling and coordination degree of agricultural resilience and rural land use efficiency and their dynamic transfer law and driving mechanisms,based on panel data of 31 provinces(municipalities and autonomous regions)in China from 2010 to *** results showed:(1)Good coupling and coordination of agricultural resilience and rural land use efficiency,with reduced temporal differentiation degrees between regions;(2)Significant spatial autocorrelation between the overall coupling and coordination degrees of agricultural resilience and rural land use efficiency,forming cold spot and hot spot spatial patterns in the western and eastern parts,respectively,with a central transition area;(3)A spillover effect of the dynamic transfer process,with a manifested specific law as"club convergence","Matthew effect",and progressive development characteristics;(4)The key roles of the natural,social,economic,and policy indicators in the coupling and coordination development process of agricultural resilience and rural land use ***,the selected indicators showed substantial spatial differences in their influences on the coupling and coordination process between provinces.

关键词： agricultural resilience rural land use efficiency coupling and coordination analysis dynamic transfer drivingmechanisms

Computational Experiments for Complex Social Systems:Integrated Design of Experiment System

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IEEE/CAA Journal of Automatica Sinica 2024年第5期11卷 1175-1189页

作者： Xiao Xue Xiangning Yu Deyu Zhou Xiao Wang Chongke Bi Shufang Wang Fei-Yue Wang college of Intelligence and Computing Tianjin UniversityTianjin 300350China School of Software Shandong UniversityJinan 250101China School of Artificial Intelligence Anhui UniversityHefei 230601China School of Geographic and environmental sciences Tianjin Normal UniversityTianjin 300387China Institute of Automation Chinese Academy of sciences Beijing 100190China

Powered by advanced information industry and intelligent technology,more and more complex systems are exhibiting characteristics of the cyber-physical-social systems(CPSS).And human factors have become crucial in the operations of complex social *** mechanical analysis and social simulations alone are powerless for analyzing complex social *** this backdrop,computational experiments have emerged as a new method for quantitative analysis of complex social systems by combining social simulation(e.g.,ABM),complexity science,and domain ***,in the process of applying computational experiments,the construction of experiment system not only considers a large number of artificial society models,but also involves a large amount of data and *** a result,how to integrate various data,model and knowledge to achieve a running experiment system has become a key *** paper proposes an integrated design framework of computational experiment system,which is composed of four parts:generation of digital subject,generation of digital object,design of operation engine,and construction of experiment ***,this paper outlines a typical case study of coal mine emergency management to verify the validity of the proposed framework.

关键词： artificial system operations

Major elements in the Holocene loess-paleosol sequence in the upper reaches of the Weihe River valley,China

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Journal of Arid Land 2016年第2期8卷 197-206页

作者： WAN Honglian HUANG Chunchang PANG Jiangli key laboratory of Disaster Monitoring and Mechanism simulation of Shaanxi province Baoji University of Arts and Sciences Department of geographical Science and environmental Engineering Baoji University of Arts and Sciences college of Tourism and environmental sciences Shaanxi Normal University

Palaeohydmlogical investigations were carried out in the Guchuan Basin in the upper reaches of the Weihe River valley, China. A set of palaeoflood slackwater deposits （SWDs） was found interbedded in the Holocene Ioess-paleosol sequence at the Guchuanzhen site （GCZ）. These palaeoflood SWDs were studied by field observations and laboratory analyses including concentrations of chemical elements and optically stimulated luminescence （OSL） dating. The results showed that the palaeoflood SWDs were the result of the secondary separations of the surface soil and weathered soil layers during the process of water transport and deposition, and without obvious weathering during soil development. These extraordinary flood events were dated back to 3,200-3,000 a B.P. with the OSL method and checked by archaeological dating of the human remains retrieved from the profile. These extraordinary flood events were therefore considered as regional expression of known climatic events and demonstrated the climatic instability in the Holocene. This result is important for understanding the effects of global climate change on the dynamics of river systems.

关键词： upper reaches of the Weihe River Holocene Ioess-paleosol sequence major elements

Astronomical forcing and sedimentary noise modeling of lake-level changes in the Middle Eocene Chezhen Sag,Bohai Bay Basin,eastern China

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Frontiers of Earth Science 2024年第2期18卷 446-459页

作者： Xuwei LUAN Jinliang ZHANG Na LI Tao CHEN Long SUN Xuecai ZHANG Faculty of geographical Science Beijing Normal UniversityBeijing 100875China college of Geosciences China University of Petroleum(Beijing)Beijing 102249China Management Center of Oil and Gas Exploration Sinopec Shengli OilfieldDongying 257000China

The accurate determination of geological age is a key to understanding the history and process of paleolake evolution and oil and gas exploration in continental lake ***,improving the accuracy of geological age has always been a difficult scientific problem.A 609-m-thick,continuous lacustrine mudstone and sandstone succession in Chezhen Sag(eastern China)provides an ideal middle Eocene sedimentary record for establishing a high-resolution stratigraphic chronology *** on spectrum analysis and sliding window spectrum analysis of the natural gamma(GR)logging data of well Che 271(C271)in Chezhen Sag,the periods of 405 kyr and 40.1 kyr were filtered by a Gaussian bandpass filter,and a“floating”astrochronological time scale(ATS)was *** total number of 405 kyr eccentricity cycles were 13.6 and 40.1 kyr obliquity cycles were 138 which recorded from the upper member 4(Es4U)to the member 3(Es3)of the Eocene Shahejie Formation,and the depositional duration was 5.53 *** Coefficient(COCO)analysis and evolutionary Correlation Coefficient(eCoCo)analysis found that the optimal sedimentary rate of different *** noise simulation revealed the history of paleolake water changes in the Middle Eocene in the Chezhen Sag,according to which four sequences are *** study shows that the lake level change of Chezhen Sag in the middle Eocene shows prominent 1.2 Myr cycles and an antiphase well-coupled relationship with obliquity ***,we propose a model to explain the relationship between the orbital cycle and lake level change in the continental lake *** the obliquity of the earth increases,the middle and high latitudes of the earth will be closer to the sun,the direct sunlight will be higher,and the meridional sunshine will increase,thus accelerating the evaporation process of lake basin *** the seasonal changes are obvious(maximum period of 1.2 Myr ultra-long obliquity),this effect is more signific

关键词： Chezhen Sag cyclostratigraphy astrochronological time scale sedimentary noise

Utilization effect of water-land resources under the evolution of Chinese dietary patterns

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Journal of geographical sciences 2023年第4期33卷 741-759页

作者： ZHU Yuanyuan WANG Ziwei ZHU Xiaohua key laboratory of Geographic process analysis&simulation hubei province Central China Normal UniversityWuhan 430079China Institute of Geographic sciences and Natural Resources Research CASBeijing 100101China

Exploring the utilization effect of water-land resources under the evolution of dietary patterns is of great significance in achieving sustainable global food consumption and the effective allocation of national *** selected study area was China,a country with rapidly changing dietary consumption patterns,and the research period was between 1987 and *** on the material called Chinese Dietary Guidelines 2021,this study introduced the“virtual water”and the“virtual land”to quantify the utilization effect of water-land resources under the evolution of Chinese dietary *** showed that the dietary patterns gradually changed from“cereal-vegetable-based consumption”to“diversified consumption”.Food consumption’s total water footprint(WF)increased from 471.1 Gm3in 1987 to 848.8 Gm3in 2020,with a growth rate of 80.2%.Moreover,the total land requirement for food(LRF)increased from 88.8 Mha in 1987 to 129.9 Mha in 2020,with a growth rate of 46.3%.Furthermore,the meat consumption was the major contributor to the increase in total WF(104.0%)and LRF(102.1%).In contrast to the balanced diet pattern,there was no waste of water-land resources consumption for the food consumption of urban-rural residents in China between 1987 and ***,the consumption of water resources would gradually approach the resource cost under the balanced diet *** would eventually break through the critical value and reach the state of resource *** addition,the findings showed that urban residents’waste rate of water-land resources for meat consumption increased by 142.3%compared with that in *** research results can provide scientific guidance for resolving the food crisis under the supply of water-land resources in China and have an essential reference for national food security and sustainable development of resources and environment.

关键词： dietary patterns water-land resource utilization food security sustainable development China