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Rural labor migration and farmers’arrangements of rice production systems in Central China:Insight from the intergenerational division of labor

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Journal of Integrative Agriculture 2024年第9期23卷 3200-3214页

作者： Xue Shen Quanyu Yang Rongjun Ao Shengsheng Gong key laboratory for geographical process analysis&simulation of hubei province/College of Urban and Environmental Sciences Central China Normal UniversityWuhan 430079China

Rice production is crucial for food security in China,and its relationship with rural labor migration has been studied *** migration in rural China has taken new forms in recent *** has been a discernible trend wherein adult children have started migrating to cities while their elderly parents return to villages to re-engage in on-farm *** phenomenon has notably shaped the intergenerational division of labor(IDL)within ***,it remains to be seen how farmers adjust their rice production systems in response to the *** age of 60 years for employment injury insurance is the eligibility threshold for off-farm employment and is used to obtain a source of exogenous variation in the *** on a representative household survey of 1,752 rice farmers in the hubei province of Central China,our fuzzy regression discontinuity analysis reveals that farmers in IDL households are more likely to adopt ratoon rice(RR)than single cropping rice(SR)or double cropping rice(DR).The effect of the IDL varies under different levels of operational scales and specialized agricultural service *** analysis suggests that farmers’arrangements are associated with two potential mechanisms of downward intergenerational *** transfer for urban housing purchases increases RR in IDL households,and time transfer for intergenerational childcare significantly promotes SR in IDL *** study enhances the understanding of the relationship between rural labor migration and rice production in China,providing a reference for adjusting rice production systems to ensure food security.

关键词： labor migration intergenerational division of labor rice production systems fuzzy regression discontinuity Central China

中国植物性饮食结构调整具有显著的耕地资源效应

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Science Bulletin 2024年第6期69卷 737-740页

作者：朱晓华张燕朱媛媛李裕瑞 Institute of geographic Sciences and Natural Resources Research Chinese Academy of SciencesBeijing 100101China key laboratory of geographic process analysis&simulation hubei province Central China Normal UniversityWuhan 430079China

Food systems are already a major contributor to land degradation,and changes in global diets will exacerbate this situation[1].Population growth and affluent dietary patterns result in changes in land demand and land-use patterns,and up to 40% of global arable land and more than 30% of global food-crop production are used for animal feed[2].Furthermore,food-feed competition can result in an inadequate food supply[3].

关键词：耕地资源 arable food

A phenology-based vegetation index for improving ratoon rice mapping using harmonized Landsat and Sentinel-2 data

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Journal of Integrative Agriculture 2024年第4期23卷 1164-1178页

作者： Yunping Chen Jie Hu Zhiwen Cai Jingya Yang Wei Zhou Qiong Hu Cong Wang Liangzhi You Baodong Xu Macro Agriculture Research Institute College of Plant Science and TechnologyHuazhong Agricultural UniversityWuhan 430070China College of Resources and Environment Huazhong Agricultural UniversityWuhan 430070China key laboratory of Agricultural Remote Sensing Ministry of Agriculture and Rural Affairs/Institute of Agricultural Resources and Regional PlanningChinese Academy of Agricultural SciencesBeijing 100081China key laboratory for geographical process analysis&simulation of hubei province/College of Urban and Environmental Sciences Central China Normal UniversityWuhan 430079China International Food Policy Research Institute NWWashingtonD.C.20005USA

Ratoon rice,which refers to a second harvest of rice obtained from the regenerated tillers originating from the stubble of the first harvested crop,plays an important role in both food security and agroecology while requiring minimal agricultural ***,accurately identifying ratoon rice crops is challenging due to the similarity of its spectral features with other rice cropping systems(e.g.,double rice).Moreover,images with a high spatiotemporal resolution are essential since ratoon rice is generally cultivated in fragmented croplands within regions that frequently exhibit cloudy and rainy *** this study,taking Qichun County in hubei province,China as an example,we developed a new phenology-based ratoon rice vegetation index(PRVI)for the purpose of ratoon rice mapping at a 30 m spatial resolution using a robust time series generated from Harmonized Landsat and Sentinel-2(HLS)*** PRVI that incorporated the red,near-infrared,and shortwave infrared 1 bands was developed based on the analysis of spectro-phenological separability and feature *** on actual field samples,the performance of the PRVI for ratoon rice mapping was carefully evaluated by comparing it to several vegetation indices,including normalized difference vegetation index(NDVI),enhanced vegetation index(EVI)and land surface water index(LSWI).The results suggested that the PRVI could sufficiently capture the specific characteristics of ratoon rice,leading to a favorable separability between ratoon rice and other land cover ***,the PRVI showed the best performance for identifying ratoon rice in the phenological phases characterized by grain filling and harvesting to tillering of the ratoon crop(GHS-TS2),indicating that only several images are required to obtain an accurate ratoon rice ***,the PRVI performed better than NDVI,EVI,LSWI and their combination at the GHS-TS2 stages,with producer's accuracy and user's accuracy of 92.22 and 89.30%,respectively

关键词： ratoon rice phenology-based ratoon rice vegetation index(PRVI) phenological phase feature selection Harmonized Landsat Sentinel-2 data

High-quality Development of Public Health in Guizhou province, China

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Journal of Resources and Ecology 2024年第4期15卷 925-936页

作者： ZHANG Jisha LUO Jing CHEN Guolei ZHANG Chunyan WANG Jishu LI Lianlian School of Geography and Environmental Science Guizhou Normal UniversityGuiyang 550025China hubei Provincial key laboratory for geographical process analysis and simulation&College of Urban and Environmental Sciences Central China Normal UniversityWuhan 430079China hubei High-quality Development Research Institute Research Office of Hubei Provincial People’s Government and Central China Normal UniversityWuhan 430079China

People’s health is the basis for the progress of social civilization and an important symbol of national prosperity and national *** the entropy method,spatial autocorrelation,spatio-temporal geographic weighted regression and other methods,we conducted a comprehensive evaluation of the high-quality development level of public health in Guizhou province from 2011 to 2020 and an evolutionary analysis of the spatio-temporal *** results revealed four key aspects of the state of public health in Guizhou province.(1)The overall level of public health is constantly improving,but structural imbalance is prominent.(2)From the spatial dimension,the spatial differences in the level of public health have gradually moved from significant to a state of *** northeastern cities were more strongly driven by the radiation of the peripheral cities,while this effect was weaker in the southwestern *** the time dimension,the spatial pattern shows a clear gradient,with a faster vertical growth rate.(3)The overall spatial correlation of the level of public health is weak,with more cold spots than hot spots,showing a distribution pattern of“strong in the northeast and weak in the southwest”.(4)The new rural cooperative medical care participation rate,(rural)per capita health expenditure,and the electronic health record creation rate have become the most important drivers affecting the high-quality development of public health in Guizhou province.

关键词： public health high-quality development entropy method Guizhou province

analysis of the Flow Field and Impact Force in High-Pressure Water Descaling

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Fluid Dynamics & Materials processing 2024年第1期20卷 165-177页

作者： Yue Cui Liyuan Wang Jian Wu Haisheng Liu Di Wu key Lab of Intelligent Equipment Digital Design and process simulation Hebei ProvinceTangshan UniversityTangshan063000China Department of Intelligent Manufacturing Tangshan Vocational College of Science and TechnologyTangshan063001China

This study aims to improve the performances of the high-pressure water descaling technology used in steel hot rolling *** particular,a 2050 mm hot rolling line is considered,and the problem is investigated by means of a fluid–structure interaction(FSI)method by which the descaling effect produced by rolling coils with different section sizes is *** a flat fan-shaped nozzle at the entrance of the R1R2 roughing mill,the outflow field characteristics and the velocity distribution curve on the strike line(at a target distance of 30–120 mm)are *** is found that the velocity in the center region of the water jet with different target distances is higher than that in the boundary *** the target distance increases,the velocity of the water jet in the central region *** comparison with experimental results,it is shown that the simulation model can accurately predict the impact position of the high-pressure water on the impact plate,thereby providing a computational scheme that can be used to optimize the nozzle space layout and improve the slabs’descent effect for different rolling specifications.

关键词： High pressure water descaling flow field analysis FSI target distance strike range

Anisotropic shearing mechanism of Kangding slate:Experimental investigation and numerical analysis

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第5期16卷 1487-1504页

作者： Ping Liu Quansheng Liu Penghai Deng Yucong Pan Yiming Lei Chenglei Du Xianqi Xie The key laboratory of Geotechnical and Structural Engineering Safety of hubei province School of Civil EngineeringWuhan UniversityWuhan430072China State key laboratory of Water Resources and Hydropower Engineering Science Wuhan UniversityWuhan430072China

The shear mechanical behavior is regarded as an essential factor affecting the stability of the surrounding rocks in underground *** shear strength and failure mechanisms of layered rock are significantly affected by the foliation *** shear tests were conducted on cubic slate samples with foliation angles of 0°,30°,45°,60°,and 90°.The effect of foliation angles on failure patterns,acoustic emission(AE)characteristics,and shear strength parameters was *** on AE characteristics,the slate failure process could be divided into four stages:quiet period,step-like increasing period,dramatic increasing period,and remission period.A new empirical expression of cohesion for layered rock was proposed,which was compared with linear and sinusoidal cohesion expressions based on the results made by this paper and previous *** comparative analysis demonstrated that the new expression has better prediction ability than other *** proposed empirical equation was used for direct shear simulations with the combined finite-discrete element method(FDEM),and it was found to align well with the experimental *** both computational efficiency and accuracy,it was recommended to use a shear rate of 0.01 m/s for FDEM to carry out direct shear *** balance the relationship between the number of elements and the simulation results in the direct shear simulations,the recommended element size is 1 mm.

关键词： Anisotropy Empirical expression of cohesion foliation angles Combined finite-discrete element method(FDEM) Shear rate Element size

Frequency and size change of ice–snow avalanches in the central Himalaya:A case from the Annapurna II glacier

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Advances in Climate Change Research 2024年第3期15卷 464-475页

作者： Yao LI Yi-Fei CUI Jian-Sheng HAO Zheng-Tao ZHANG Hao WANG Jian GUO Shuo-Fan WANG State key laboratory of Hydroscience and Engineering Department of Hydraulic EngineeringTsinghua UniversityBeijing 100084China key laboratory of Hydrosphere Sciences of the Ministry of Water Resources Beijing 100084China key laboratory of Land Surface Pattern and simulation Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China School of National Safety and Emergency Management Beijing Normal UniversityBeijing 100875China key laboratory of Mountain Hazards and Earth Surface process Institute of Mountain Hazards and EnvironmentChinese Academy of SciencesChengdu 610041China

Glaciers have retreated and shrunk in High Mountain Asia since the mid-20th century because of global warming,leading to glacier instability and hazardous iceesnow ***,the complex relationship between iceesnow avalanches and factors such as climate and potential triggers are difficult to understand because of the lack of observational ***,we addressed iceesnow avalanches on the Annapurna II glacier in Nepal,Central *** constructed an iceesnow avalanche history using long-term multi-source remote sensing images(1988-2021)and mapped the velocity fields of glaciers using cross-correlation analysis on SAR and optical ***,we investigated the impact of climate change and earthquakes on the frequency and size of iceesnow *** results demonstrate that the frequency of iceesnow avalanches has increased from 10 in 1988 to 27 in 2020,but the average area of iceesnow avalanche deposits has decreased by approximately 70%,from 3.4×10^(5) m^(2) in 1988 to 1.2×10^(5) m^(2) in *** evolutionary characteristic of ice avalanches is linked to the impact of glacier retreat(reduction in ice material supply)and increased activity under climate *** glacier movement velocity controls the size of iceesnow avalanches and can be set as an indicator for iceesnow avalanche *** the Annapurna Ⅱ glacier,an iceesnow avalanche occurred when the glacier velocities were greater than 1.5 m d^(-1).These results offer insights into iceesnow avalanche risk assessment and prediction in high-mountain areas,particularly in regions characterised by dense glacier distribution.

关键词： Iceesnow avalanche Glacier instability Climate change Central Himalaya Remote sensing

Antecedent snowmelt and orographic precipitation contributions to water supply of Pakistan disastrous floods,2022

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Advances in Climate Change Research 2024年第3期15卷 419-430页

作者： Yan WANG Peng CUI Chen-Di ZHANG Guo-Tao ZHANG Jian-Sheng HAO Xu YUAN Yao-Zhi JIANG Lu WANG key laboratory of Land Surface Pattern and simulation Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China key laboratory of Mountain Hazards and Earth Surface process Institute of Mountain Hazards and EnvironmentChinese Academy of SciencesChengdu 610299China Polar and Marine Research Institute College of Harbor and Coastal EngineeringJimei UniversityXiamen 361021China School of Resources and Environment University of Electronic Science and Technology of ChinaChengdu 610054China Hebei province Tangshan Caofeidian Meteorological Bureau Tangshan 063000China

In 2022,the Pakistan witnessed the hottest spring and wettest summer in *** devastating floods inundated a large portion of Pakistan and caused enormous ***,the primary water source and its contributions to these unprecedented floods remain *** on the reservoir inflow measurements,Multi-Source Weighted-Ensemble Precipitation(MSWEP),the fifth generation ECMWF atmospheric reanalysis(ERA5)products,this study quantified the contributions of monsoon precipitation,antecedent snow-melts,and orographic precipitation enhancement to floods in *** found that the Indus experienced at least four inflow up-rushes,which was mainly supplied by precipitation and snowmelt;In upper Indus,abnormally high temperature continued to influence the whole summer and lead to large amounts of snowmelts which not only was a key water supply to the flood but also provided favorable soil moisture conditions for the latter *** July,the snowmelt has higher contributions than the precipitation to the streamflow of Indus River,with contribution value of more than 60%.Moreover,the snowmelt could still supply 20%-40%water to the lower Indus in July and August;The leading driver of 2022 mega-floods over the southern Pakistan in July and August was dominated by the precipitation,where terrain disturbance induced precipitation account to approximately 33%over the southern *** results help to understand the mechanisms of flood formation,and to better predict future flood risks over complex terrain regions.

关键词： Extreme heavy rainfall Snowmelt Orographic precipitation Floods Pakistan

Refining the Factors Affecting N_(2)O Emissions from Upland Soils with and without Nitrogen Fertilizer Application at a Global Scale

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Advances in Atmospheric Sciences 2024年第9期41卷 1804-1820页

作者： Wenqian JIANG Siqi LI Yong LI Meihui WANG Bo WANG Ji LIU Jianlin SHEN Xunhua ZHENG State key laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China key laboratory for Agro-ecological processes in Subtropical Regions Institute of Subtropical AgricultureChinese Academy of SciencesChangsha 410125China Changsha Research Station for Agricultural&Environmental Monitoring Chinese Academy of SciencesChangsha 410125China University of Chinese Academy of Sciences Beijing 100049China State Environmental Protection key laboratory of Formation and Prevention of the Urban Air Pollution Complex Shanghai Academy of Environment SciencesShanghai 200233China Institute of Carbon Neutrality Qilu ZhongkeJinan 251699China hubei province key laboratory for geographical process analysis and simulation Central China Normal UniversityWuhan 430079China Department of Ecohydrology Leibniz Institute of Freshwater Ecology and Inland FisheriesBerlin 12587Germany key laboratory of Environment Change and Resources Use in Beibu Gulf Ministry of EducationNanning Normal UniversityNanning 530001China Golden Mantis school of Architecture Soochow UniversitySuzhou 215123China

Nitrous oxide(N_(2)O)is a long-lived greenhouse gas that mainly originates from agricultural *** and more studies have explored the sources,influencing factors and effective mitigation measures of N_(2)O in recent ***,the hierarchy of factors influencing N_(2)O emissions from agricultural soils at the global scale remains *** this study,we carry out correlation and structural equation modeling analysis on a global N_(2)O emission dataset to explore the hierarchy of influencing factors affecting N_(2)O emissions from the nitrogen(N)and non-N fertilized upland farming systems,in terms of climatic factors,soil properties,and agricultural *** results show that the average N_(2)O emission intensity in the N fertilized soils(17.83 g N ha^(-1)d^(-1))was significantly greater than that in the non-N fertilized soils(5.34 g N ha^(−1) d^(−1))(pkey in the temperate *** fertilizer,the primary influence factors for subtropical monsoon and temperate continental zones are soil physical properties,while agricultural measures are the main factors in the temperate monsoon *** enhanced agricultural practices,such as reduced N fertilizer rate combined with the addition of nitrification and urease inhibitors can potentially mitigate N_(2)O emissions by more than 60%in upland farming systems.

关键词： N_(2)O emissions influencing factors nitrogen cycling upland farming systems