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A township-level assessment of forest fragmentation using morphological spatial pattern analysis in Qujing,Yunnan Province,China
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作者 HUANG Xiao-yuan YE Yuan-hui +4 位作者 ZHANG Zhuo-ya YE Jiang-xia GAO Jie Marc BOGONOVICH ZHANG Xing 《Journal of Mountain Science》 SCIE CSCD 2021年第12期3125-3137,共13页
Forest fragmentation is an integral part of global change.Understanding forest fragmentation patterns and dynamics are of great significance for maintaining ecosystem stability.There are great differences in the inter... Forest fragmentation is an integral part of global change.Understanding forest fragmentation patterns and dynamics are of great significance for maintaining ecosystem stability.There are great differences in the interference of natural and human factors on forests in different towns of mountainous cities,and the characteristics of forest fragmentation are also obviously different.Forest fragmentation has been broadly studied,yet,it remains poorly understood at the township-scale within mountainous cities.In this study,the spatial form of forest landscape and forest fragmentation modes of towns were examined in Qujing City,Yunnan Province,China for the years of 2006 and 2016,relying heavily on the morphological spatial pattern analysis(MSPA)and K-means clustering algorithm.Results in 2016 showed that the forest landscape morphology of Qujing could be divided into seven classes:core,perforation,islet,bridge,edge,branch and ring;with landscape areas of 41.94%,1.22%,7.04%,11.12%,23.26%,11.74%and 3.68%respectively.Compared with 2006,the changes of landscape area were 1.71%,0.02%,0.30%,1.65%,0.20%,0.19%and 0.05%respectively.The townships in Qujing varied significantly in their landscape fragmentation patterns,and these patterns were spatially dependent.Different forest landscape forms have positive spatial correlations and differences.The forest fragmentation modes of towns can be divided into four types:Low anthropogenic towns,high anthropogenic towns,complex terrain towns and gentle terrain towns.Different ways of human activities play a decisive role in forest landscape fragmentation.The expansion of construction land and agricultural land intensifies forest fragmentation;however,man-made orderly and planned ecological restoration will greatly improve the forest coverage and improve the spatial form of urban forest landscape. 展开更多
关键词 Forest fragmentation morphological spatial pattern analysis morphological type China
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Revealing the Landform Types and Morphologic Features of Lunar Surface 被引量:1
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作者 CHENG Weiming 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2017年第4期1517-1518,共2页
A lunar geologic map at a scale of 1:5000000 was finished in the 1970s by the National Aeronautics and Space Administration, U.S U.S. Geological Survey. Department of the Interior, Till now, the landform classificati... A lunar geologic map at a scale of 1:5000000 was finished in the 1970s by the National Aeronautics and Space Administration, U.S U.S. Geological Survey. Department of the Interior, Till now, the landform classification system and lunar morphologic mapping have not been clarified. The work aims to put forward a new landform classification system and to obtain index and map in the Sheet H010. Some key morphologic features of lunar surface were compared with those of the Earth. This research is very important for whole lunar morphologic mapping and unraveling evolutionary progress. 展开更多
关键词 THAN Revealing the Landform types and Morphologic Features of Lunar Surface
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Effect of In_xGa_(1-x)As Interlayer on Surface Morphology and Optical Properties of GaSb/InGaAs Type-Ⅱ Quantum Dots Grown on InP (100) Substrates
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作者 陈虞龙 高优 +4 位作者 陈弘 张辉 何苗 李述体 郑树文 《Chinese Physics Letters》 SCIE CAS CSCD 2016年第9期120-123,共4页
The effects of indium composition in InGaAs interlayer and on optical properties of GaSb/InGaAs QD material on morphology of GaSb/InGaAs quantum dots (QDs) system are studied. AFM images show that the change of the ... The effects of indium composition in InGaAs interlayer and on optical properties of GaSb/InGaAs QD material on morphology of GaSb/InGaAs quantum dots (QDs) system are studied. AFM images show that the change of the indium composition in InGaAs interlayer can alter the GaSb QD morphology. It is found that low indium composition in InGaAs interlayer can promote the formation of QDs, while high indium composition can inhibit the formation of QDs. The photoluminescence (PL) spectra of GaSb/InGaAs QDs at 8 K under low excitation power indicate that the third root of the excitation power is linear with the peak position, which provides a direct evidence for their luminescence belonging to type-Ⅱ material optical transition. The PL spectra at 8 K under an excitation power of 90row show that the optical properties of GaSb/InGaAs QD material system can be affected by the indium composition in the InGaAs interlayer, and the PL peak position is linear with the indium composition. The optical properties of GaSb/InGaAs QDs can be improved by adjusting the indium composition in the InGaAs interlayer. 展开更多
关键词 INGAAS in it GASB Quantum Dots Grown on InP SUBSTRATES x)As Interlayer on Surface Morphology and Optical Properties of GaSb/InGaAs type of on
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3-D Seismic Identification and Characterization of Ancient Channel Morphology 被引量:4
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作者 蒲仁海 朱李 钟红利 《Journal of Earth Science》 SCIE CAS CSCD 2009年第5期858-867,共10页
It is easy to identify ancient fluvial morphologic types by the outcrop,log and core data.However,the horizontal distribution and geometry of the channels can only be identified and predicted by relying on the 3-D sei... It is easy to identify ancient fluvial morphologic types by the outcrop,log and core data.However,the horizontal distribution and geometry of the channels can only be identified and predicted by relying on the 3-D seismic data.The 3-D seismic horizon slices,especially,can play an important role in the sandstone prediction of meandering rivers,distributary channels and low-sinuosity channels.Every microfacies unit,including main channels,such as sinuous or branching channels,levee,crevasse channels,ligule crevasse splay and floodplain etc.can be identified.Braided channel sandstones are planar tabular lateral-connected sandbodies and the distribution of thick main channel belts can only be identified from 3-D seismic data.As the braided sandstones are ubiquitous,their occurrence and distribution do not need to be predicted.Generally,the coal velocity is so low that it can create a strong amplitude reflection in coal strata.It consequently conceals the amplitude respondence to anastomosing channel sandstone which could be identified from 3-D seismic inversion data sometimes.Case studies of mud-rich low-sinuosity rivers identified with 3-D seismic data indicate that the scales and width-to-thickness ratio of such sandbodies are small,laterally unconnected,and generally occurred on distant or further parts of an alluvial fan under dry climate conditions.Sometimes extraction of seismic attributes of every reflection event along horizons is expected to maximize expression of the spatial evolutions of ancient channels. 展开更多
关键词 sandbody identification morphologic river type 3-D seismic explanation low-sinuositychannel.
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Revision of genera in Asterinales
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作者 Sinang Hongsanan Yan-Mei Li +15 位作者 Jian-Kui Liu Tina Hofmann Meike Piepenbring Jayarama D.Bhat Saranyaphat Boonmee Mingkhuan Doilom Chonticha Singtripop Qing Tian Ausana Mapook Xiang-Yu Zeng Ali H.Bahkali Jian-Chu Xu Peter E.Mortimer Xia-Hai Wu Jun-Bo Yang Kevin D.Hyde 《Fungal Diversity》 SCIE 2014年第5期1-68,共68页
The order Asterinales comprises a single family,Asterinaceae.In this study,types or specimens of 41 genera of Asterinaceae are re-examined and re-described and illustrated by micrographs.Seventeen genera,namely Asteri... The order Asterinales comprises a single family,Asterinaceae.In this study,types or specimens of 41 genera of Asterinaceae are re-examined and re-described and illustrated by micrographs.Seventeen genera,namely Asterina(type genus),Asterinella,Asterotexis,Batistinula,Cirsosia,Echidnodella,Halbania,Lembosia,Meliolaster,Parasterinopsis,Platypeltella,Prillieuxina,Schenckiella(=Allothyrium),Trichasterina,Trichopeltospora,Uleothyrium and Vizellopsis,are maintained within Asterinaceae.Echidnodes,Lembosiella,Lembosina,Morenoina,and Thyriopsi s are transferred to Aulographaceae based on morphological and molecular characteristics.Anariste is transferred to Micropeltidaceae,while Lembosiopsis is transferred to Mycosphaerellaceae.Placoasterella and Placosoma are morphologically close to taxa in Parmulariaceae,where they are transferred.Aulographina is placed in Teratosphaeriaceae,while Asterodothis,Asterinema,Dothidasteromella,Leveillella,Petrakina and Stephanotheca are transferred to Dothideomycetes,genera incertae sedis.Eupelte,Macowaniella,Maheshwaramyces,Parasterinella,and Vishnumyces are treated as doubtful genera,because of lack of morphological and molecular data.Aphanopeltis,Asterolibertia,Neostomella,Placoasterina,and Symphaster are synonyms of Asterina based on morphology,while Trichamelia,Viegasia,and Yamamotoa are synonyms of Lembosia.The characteristics of each family are discussed and a phylogenetic tree is included. 展开更多
关键词 Asterina Asterinaceae Aulographaceae Lembosiaceae morphology type species taxonomy
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