It is crucial to investigate the urban agglomerations spatio-temporal evolution patterns and driving factors for analyzing the urban spatial structure-functional division and promoting the coordinated development of u...It is crucial to investigate the urban agglomerations spatio-temporal evolution patterns and driving factors for analyzing the urban spatial structure-functional division and promoting the coordinated development of urban agglomerations.In this study,a novel vegetation-building-nighttime light-adjusted index(VBNAI)was established for rapid and effective mapping of urban construction land(UCL)in Central Plains Urban Agglomeration(CPUA),China during 2000–2020 based on Google Earth Engine(GEE)platform.Compared with traditional indices,VBNAI can significantly decrease the blooming effect,Normalized Difference Vegetation Index(NDVI)saturation,and soil background of nighttime light data.In addition,the urban expansion indices and standard deviation ellipse model were synthetically adopted to analyze the spatio-temporal evolution pattern of urban expansion.The gravity model and the geographically weighted regression model were employed to determine the spatial interaction forces and drivers of urban expansion,respectively.The results showed that the VBNAI index has obvious advantages in efficiency and accuracy to extract UCL with the overall accuracy of more than 91%.The UCL of CPUA had increased by 4489.84 km2 during 2000–2020 with the gravity center moving towards southeast continuously.From 2000 to 2010,the urban expansion was in a‘center-hinterland’pattern which had benefit from the favorable effect of the traffic shaft belt.During 2010–2020,the urban network structure had basically established.Urban expansion had been influenced by a variety of socio-economic and demographic factors,and the impact degree varied from region to region.This study could provide scientific references for facilitating the intensive utilization of urban resources and optimizing the spatial development pattern of urban agglomeration.展开更多
正China's Henan province, brief as Yu, got its name from the Yu state, which was one of the nine states in ancient China. The place with geographical advantage possesses superiority of radiating to the whole natio...正China's Henan province, brief as Yu, got its name from the Yu state, which was one of the nine states in ancient China. The place with geographical advantage possesses superiority of radiating to the whole nation, and vibrant cultures, thus leading to its prosperity. The Xia, Shang and Zhou dynasties in ancient China set capitals in Luoyang of Henan province,展开更多
Abstract The level of emergency ability directly reflects response effect of an area to emergency. Taking Central Plains Economic Zone as re- search object, by documents retrieval, field survey, mechanism analysis and...Abstract The level of emergency ability directly reflects response effect of an area to emergency. Taking Central Plains Economic Zone as re- search object, by documents retrieval, field survey, mechanism analysis and logical reasoning, evaluation index system for emergency ability of ag- ricultural environmental pollution incident was established, which included 5 first grade indexes, 19 second grade indexes and 53 third grade inde- xes. By mechanism analysis and mathematical derivation, evaluation model for emergency ability of agricultural environmental pollution incident： I =m∑i=1∑j=1Pij, On this basis, four prefecture-level cities （A, B, C and D） of Central Plains Economic Zone were evaluated by using the index system and the evaluated model. The research could provide important theoretical reference for emergency ability construction of agricultural environmental pol- lution incident in Central Plains Economic Zone.展开更多
Visceral leishmaniasis(VL)(kala-azar)was most seriously prevalent in the plain regions of eight provinces/municipalities in the eastern and central parts of China.In the early 1950s,the number of counties/cities endem...Visceral leishmaniasis(VL)(kala-azar)was most seriously prevalent in the plain regions of eight provinces/municipalities in the eastern and central parts of China.In the early 1950s,the number of counties/cities endemic for VL and the number of cases in the plain regions accounted for 60%and 80%,respectively,of the total numbers in the entire country.By implementing comprehensive control measures,including treatment of patients for eliminating the source of infection and spraying insecticide in endemic villages to kill sandflies,VL transmission has been brought under control in this region by the early 1960s,and no new infected cases have been found since 1983,achieving the goal of eliminating VL.展开更多
The Mangshan loess on China’s Central Plain, located on the transitional zone between the uplifting Loess Plateau and the subsiding North China Plain, is a proximal sandy loess transported from the fanhead of alluvia...The Mangshan loess on China’s Central Plain, located on the transitional zone between the uplifting Loess Plateau and the subsiding North China Plain, is a proximal sandy loess transported from the fanhead of alluvial fan in the lower reaches of the Yellow River and has recorded the coupling effect of the tectonics and climate over the last 200 ka. An abrupt environmental change indicated by the abrupt rise of deposit rate in the late penultimate glaciation, about 150 ka BP, took place; that is, the Yellow River downcut and moved eastwards through the Sanmenxia Gorge and transported abundant materials from the Loess Plateau to form paleosol S1 with a thickness of 15.7 m and loess L1 with a thickness of 77.3 m. The loess-paleosol sequence at Mangshan has not only recorded detailed climate responses of this area to the East Asian monsoon, but also reflects the tectonogenetic environmental effect caused by the trunk stream of the Yellow River cutting through Sanmenxia Gorge into sea.展开更多
Extensive studies on aerosol chemistry have been carried out in megacities in China,however,aerosol characterization in Central China Plain(CCP)is limited.Here we conducted real-time measurements of fine particle comp...Extensive studies on aerosol chemistry have been carried out in megacities in China,however,aerosol characterization in Central China Plain(CCP)is limited.Here we conducted real-time measurements of fine particle composition with a time-of-flight aerosol chemical speciation monitor in Kaifeng,Henan province in October 2019.Our results showed that nitrate and organics constituted the major fraction of non-refractory PM_(2.5)for the entire study,on average accounting for 34%and 33%,respectively.However,aerosol composition was substantially different among four periods due to different meteorological conditions and chemical processing.For instance,nitrate presented the lowest contribution during the first period due to evaporative loss associated with high temperature(T),and then rapidly increased during polluted periods as a function of relative humidity(RH).Positive matrix factorization analysis showed the dominance of secondary organic aerosol(SOA)in OA,and also the changes in OA composition under different T and RH levels.In addition,this study is unique with two periods of local emission controls.Back trajectory and coefficient of divergence analysis showed that air pollution in CCP was overall homogeneously distributed.As a result,the effectiveness of local emission controls in this region was strongly affected by meteorological conditions and regional transport.We found that one of the periods with emission control even showed the highest concentrations for the entire study.Our results point towards the limited effect of local emission controls in mitigating air pollution in CCP,and highlight the importance of joint emission controls under unfavorable meteorological conditions.展开更多
基金Under the auspices of Social Science and Humanity on Young Fund of the Ministry of Education of China(No.21YJCZH100)the Scientific Research Project on Outstanding Young of the Fujian Agriculture and Forestry University(No.XJQ201920)+1 种基金the Science and Technology Innovation Special Fund Project of Fujian Agriculture and Forestry University(No.CXZX2021032)the Forestry Peak Discipline Construction Project of Fujian Agriculture and Forestry University(No.72202200205)。
文摘It is crucial to investigate the urban agglomerations spatio-temporal evolution patterns and driving factors for analyzing the urban spatial structure-functional division and promoting the coordinated development of urban agglomerations.In this study,a novel vegetation-building-nighttime light-adjusted index(VBNAI)was established for rapid and effective mapping of urban construction land(UCL)in Central Plains Urban Agglomeration(CPUA),China during 2000–2020 based on Google Earth Engine(GEE)platform.Compared with traditional indices,VBNAI can significantly decrease the blooming effect,Normalized Difference Vegetation Index(NDVI)saturation,and soil background of nighttime light data.In addition,the urban expansion indices and standard deviation ellipse model were synthetically adopted to analyze the spatio-temporal evolution pattern of urban expansion.The gravity model and the geographically weighted regression model were employed to determine the spatial interaction forces and drivers of urban expansion,respectively.The results showed that the VBNAI index has obvious advantages in efficiency and accuracy to extract UCL with the overall accuracy of more than 91%.The UCL of CPUA had increased by 4489.84 km2 during 2000–2020 with the gravity center moving towards southeast continuously.From 2000 to 2010,the urban expansion was in a‘center-hinterland’pattern which had benefit from the favorable effect of the traffic shaft belt.During 2010–2020,the urban network structure had basically established.Urban expansion had been influenced by a variety of socio-economic and demographic factors,and the impact degree varied from region to region.This study could provide scientific references for facilitating the intensive utilization of urban resources and optimizing the spatial development pattern of urban agglomeration.
文摘正China's Henan province, brief as Yu, got its name from the Yu state, which was one of the nine states in ancient China. The place with geographical advantage possesses superiority of radiating to the whole nation, and vibrant cultures, thus leading to its prosperity. The Xia, Shang and Zhou dynasties in ancient China set capitals in Luoyang of Henan province,
基金Supported by Key Science Research Project for Henan Higher School,China(15A610012)Key Project of Humanity and Social Science,Henan Education Department,China(2015-ZD-029)Doctor Foundation Project of Henan Polytechnic University,China(B2012-008)
文摘Abstract The level of emergency ability directly reflects response effect of an area to emergency. Taking Central Plains Economic Zone as re- search object, by documents retrieval, field survey, mechanism analysis and logical reasoning, evaluation index system for emergency ability of ag- ricultural environmental pollution incident was established, which included 5 first grade indexes, 19 second grade indexes and 53 third grade inde- xes. By mechanism analysis and mathematical derivation, evaluation model for emergency ability of agricultural environmental pollution incident： I =m∑i=1∑j=1Pij, On this basis, four prefecture-level cities （A, B, C and D） of Central Plains Economic Zone were evaluated by using the index system and the evaluated model. The research could provide important theoretical reference for emergency ability construction of agricultural environmental pol- lution incident in Central Plains Economic Zone.
文摘Visceral leishmaniasis(VL)(kala-azar)was most seriously prevalent in the plain regions of eight provinces/municipalities in the eastern and central parts of China.In the early 1950s,the number of counties/cities endemic for VL and the number of cases in the plain regions accounted for 60%and 80%,respectively,of the total numbers in the entire country.By implementing comprehensive control measures,including treatment of patients for eliminating the source of infection and spraying insecticide in endemic villages to kill sandflies,VL transmission has been brought under control in this region by the early 1960s,and no new infected cases have been found since 1983,achieving the goal of eliminating VL.
基金Project supported by the National Natural Science Foundation of China (Grant No. 49572132).
文摘The Mangshan loess on China’s Central Plain, located on the transitional zone between the uplifting Loess Plateau and the subsiding North China Plain, is a proximal sandy loess transported from the fanhead of alluvial fan in the lower reaches of the Yellow River and has recorded the coupling effect of the tectonics and climate over the last 200 ka. An abrupt environmental change indicated by the abrupt rise of deposit rate in the late penultimate glaciation, about 150 ka BP, took place; that is, the Yellow River downcut and moved eastwards through the Sanmenxia Gorge and transported abundant materials from the Loess Plateau to form paleosol S1 with a thickness of 15.7 m and loess L1 with a thickness of 77.3 m. The loess-paleosol sequence at Mangshan has not only recorded detailed climate responses of this area to the East Asian monsoon, but also reflects the tectonogenetic environmental effect caused by the trunk stream of the Yellow River cutting through Sanmenxia Gorge into sea.
基金supported by the National Key Research and Development Program of China(No.2019YFC0214200)the Strategic Priority Research Program of the Chinese Academy of Sciences(No.XDA23020301)。
文摘Extensive studies on aerosol chemistry have been carried out in megacities in China,however,aerosol characterization in Central China Plain(CCP)is limited.Here we conducted real-time measurements of fine particle composition with a time-of-flight aerosol chemical speciation monitor in Kaifeng,Henan province in October 2019.Our results showed that nitrate and organics constituted the major fraction of non-refractory PM_(2.5)for the entire study,on average accounting for 34%and 33%,respectively.However,aerosol composition was substantially different among four periods due to different meteorological conditions and chemical processing.For instance,nitrate presented the lowest contribution during the first period due to evaporative loss associated with high temperature(T),and then rapidly increased during polluted periods as a function of relative humidity(RH).Positive matrix factorization analysis showed the dominance of secondary organic aerosol(SOA)in OA,and also the changes in OA composition under different T and RH levels.In addition,this study is unique with two periods of local emission controls.Back trajectory and coefficient of divergence analysis showed that air pollution in CCP was overall homogeneously distributed.As a result,the effectiveness of local emission controls in this region was strongly affected by meteorological conditions and regional transport.We found that one of the periods with emission control even showed the highest concentrations for the entire study.Our results point towards the limited effect of local emission controls in mitigating air pollution in CCP,and highlight the importance of joint emission controls under unfavorable meteorological conditions.
