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Description and Phylogenetic Position of Dinosaur Eggshells from the Luanchuan Area of Western henan province,china

Acta Geologica Sinica(English Edition) 2011年第1期85卷 66-74页

作者： Kohei TANAKA LU Junchang Yoshitsugu KOBAYASHI Darla K. ZELENITSKY XU Li JIA Songhai QIN Shuang TANG Min＇ an Department of Geoscience University of Calgary Calgary T2N 1N4 Canada Institute of Geology Chinese Academy of Geological Sciences Beijing 10037 China Hokkaido University Museum Hokkaido University Sapporo 060-0810 Japan henan Geological Museum Zhengzhou 450016 China North china University of Water Conservancy and Electric Power Zhengzhou 450011 China

Here, we examine 145 dinosaur eggshells from a new fossil locality in the Qiupa Formation （Upper Cretaceous） of the Luanchuan area in western henan province, china. The eggshells display elongatoolithid macro- and microstructures, including ridges and nodes on the outer surface, two ultrastructurai layers, and an undulatory boundary between the mammillary and continuous layers. A phylogenic analysis shows that the Luanchuan eggshells belong to the ooclade Elongatoolithidae. Within Elongatoolithidae, the thickness ratio of the mammillary layer to the entire eggshell, and the porosity of the Luanchuan eggshells are comparable to the oogenera Macroolithus and Elongatoolithus. There is no direct evidence for the taxonomic identity of the Luanchuan eggshells; however, they were likely laid by oviraptorids based on their phylogenetic position and their similarities with known oviraptorid eggs.

关键词： dinosaur eggshells Qiupa Formation Late Cretaceous Luanchuan henan province,china

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Winter Wheat Yield Estimation Based on Sparrow Search Algorithm Combined with Random Forest:A Case Study in henan province,china

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Chinese Geographical Science 2024年第2期34卷 342-356页

作者： SHI Xiaoliang CHEN Jiajun DING Hao YANG Yuanqi ZHANG Yan College of Geomatics Xi’an University of Science and TechnologyXi’an 710054China

Precise and timely prediction of crop yields is crucial for food security and the development of agricultural ***,crop yield is influenced by multiple factors within complex growth *** research has paid relatively little attention to the interference of environmental factors and drought on the growth of winter ***,there is an urgent need for more effective methods to explore the inherent relationship between these factors and crop yield,making precise yield prediction increasingly *** study was based on four type of indicators including meteorological,crop growth status,environmental,and drought index,from October 2003 to June 2019 in henan province as the basic data for predicting winter wheat *** the sparrow search al-gorithm combined with random forest(SSA-RF)under different input indicators,accuracy of winter wheat yield estimation was *** estimation accuracy of SSA-RF was compared with partial least squares regression(PLSR),extreme gradient boosting(XG-Boost),and random forest(RF)***,the determined optimal yield estimation method was used to predict winter wheat yield in three typical *** are the findings:1)the SSA-RF demonstrates superior performance in estimating winter wheat yield compared to other *** best yield estimation method is achieved by four types indicators’composition with SSA-RF)(R^(2)=0.805,RRMSE=9.9%.2)Crops growth status and environmental indicators play significant roles in wheat yield estimation,accounting for 46%and 22%of the yield importance among all indicators,respectively.3)Selecting indicators from October to April of the follow-ing year yielded the highest accuracy in winter wheat yield estimation,with an R^(2)of 0.826 and an RMSE of 9.0%.Yield estimates can be completed two months before the winter wheat harvest in June.4)The predicted performance will be slightly affected by severe *** with severe drought year(201

关键词： winter wheat yield estimation sparrow search algorithm combined with random forest(SSA-RF) machine learning multi-source indicator optimal lead time henan province,china

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Spatiotemporal Evolution and Influencing Factors of Urban-rural Construction Land in Rural Industrialized Areas in china:Case Studies in Changyuan City and Xinxiang County of henan province

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Chinese Geographical Science 2023年第5期33卷 850-864页

作者： SHI Yanwen LI Xiaojian HU Xueyao LI Zeyi Collaborative Innovation Center of Urban-rural Coordination/School of Resources and Environment Henan University of Economics and LawZhengzhou 450046China china Center for International Economic Exchanges Beijing 100050China College of Geography and Environmental Science Henan UniversityKaifeng 475000China

Since china’s reform and opening up in 1978,the acceleration of industrialization and urbanization in china had led to dramatic changes in the pattern of urban-rural land *** this paper,we focused on the rural industrialized areas in central china(Xinxiang County and Changyuan City of henan province).We used the average nearest neighbor index,spatial statistical analysis,and a structural equation model to analyze the spatiotemporal evolution and influencing factors of urban-rural construction land based on multisource spatial data and survey *** results showed that:1)from 1975 to 2019,the spatial distribution of urban-rural construction land in rural industrialized areas had evolved from homogeneous distribution to local *** terms of comparative analysis of cases,the spatial distribution of urban-rural construction land in Changyuan City had shown a trend from diffusion to agglomeration,and Xinxiang County had overall shown a spatial change from homogenization to agglomeration and then to regional integration development.2)The hot spots with increased urban-rural construction land significantly expanded,and they had a high degree of spatial overlap with industrial *** them,Xinxiang County was concentrated in central and marginal areas,and Changyuan was mainly concentrated in central urban areas.3)From the evolution of spatial proximity of urban-rural construction land,rural industrialized areas generally decline,showing the characteristics of internal differentiation in the rate of change.4)Industrial development,social economy,the policy environment,and urban development played a positive role in promoting the expansion of urban-rural construction land in rural industrialized *** promote the optimal use of regional land and the integrated development of urban-rural areas,we should combine the advantages of regional endowment,formulate development strategies according to local conditions,and adjust the way that land is used in

关键词： urban-rural construction land rural industrialized areas spatiotemporal evolution influencing factors rural industrialization henan province,china

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Evaluation of Ecological Carrying Capacity of henan province under the Sustainable Development

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Asian Agricultural Research 2010年第6期2卷 60-64页

作者： JIANG Xiao-ping Huazhong University of Science and Technology Wuhan 430074China Zhongzhou University Zhengzhou 430074China

Based on the overview of social economy of henan province,I probe into the concept and evaluation of ecological carrying *** using the ecological footprint analysis and the data of various kinds of land supply of henan province from 2000 to 2008,the ecological carrying capacity of henan province is *** is unveiled that inharmonious population,natural resources and economic resources affect the efficiency of the sustainable development of ecological carrying capacity of henan province;the underdeveloped economy of henan province impacts the sustainable development of ecological carrying capacity of henan province and the overburdened population lead to the insufficiency of ecological carrying *** protecting the threshold of ecological system,the countermeasures are put forward,which cover forming the idea of ecological economy and circular economy and promoting the transformation of economy growth mode;taking the development road of using resources intensively and performing the strategy of sustainable utilization of resources;strictly control population growth and strengthening people's crisis awareness of resources and environment.

关键词： Ecological carrying capacity Ecological footprint analysis threshold henan province,china

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