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Grouping tree species to estimate basal area increment in temperate multispecies forests in Durango,Mexico
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作者 Jaime Roberto Padilla-Martínez Carola Paul +2 位作者 Kai Husmann Jose Javier Corral-Rivas Klaus von Gadow 《Forest Ecosystems》 SCIE CSCD 2024年第1期1-13,共13页
Multispecies forests have received increased scientific attention,driven by the hypothesis that biodiversity improves ecological resilience.However,a greater species diversity presents challenges for forest management... Multispecies forests have received increased scientific attention,driven by the hypothesis that biodiversity improves ecological resilience.However,a greater species diversity presents challenges for forest management and research.Our study aims to develop basal area growth models for tree species cohorts.The analysis is based on a dataset of 423 permanent plots(2,500 m^(2))located in temperate forests in Durango,Mexico.First,we define tree species cohorts based on individual and neighborhood-based variables using a combination of principal component and cluster analyses.Then,we estimate the basal area increment of each cohort through the generalized additive model to describe the effect of tree size,competition,stand density and site quality.The principal component and cluster analyses assign a total of 37 tree species to eight cohorts that differed primarily with regard to the distribution of tree size and vertical position within the community.The generalized additive models provide satisfactory estimates of tree growth for the species cohorts,explaining between 19 and 53 percent of the total variation of basal area increment,and highlight the following results:i)most cohorts show a"rise-and-fall"effect of tree size on tree growth;ii)surprisingly,the competition index"basal area of larger trees"had showed a positive effect in four of the eight cohorts;iii)stand density had a negative effect on basal area increment,though the effect was minor in medium-and high-density stands,and iv)basal area growth was positively correlated with site quality except for an oak cohort.The developed species cohorts and growth models provide insight into their particular ecological features and growth patterns that may support the development of sustainable management strategies for temperate multispecies forests. 展开更多
关键词 Temperate multispecies forests Cluster analysis Basal area increment Generalized additive models
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Dermal thickness,rather than drug concentration and injection speed,influences the effective area of botulinum toxin type A in the dermis
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作者 Yixin Sun Wangfei Mo +5 位作者 Yunzhu Li Ruijia Dong Cheng Chen Jing Gao Nanze Yu Xiao Long 《Chinese Journal of Plastic and Reconstructive Surgery》 2024年第3期130-134,共5页
Background:Recently,microbotulinum,a new technique that involves injecting botulinum toxin type A(BoNTA)microdroplets into superficial cutaneous tissue,has gained popularity.The precise distribution of BoNTA in the ta... Background:Recently,microbotulinum,a new technique that involves injecting botulinum toxin type A(BoNTA)microdroplets into superficial cutaneous tissue,has gained popularity.The precise distribution of BoNTA in the targeted area profoundly affects outcomes.Many factors may influence the effective area of BoNTA in the dermis.This study aimed to determine the dermal distribution properties of BoNTA to guide microbotulinum injection.Methods:Ten healthy males aged 18–65 years without BoNTA treatment in the previous year were recruited to receive intradermal injections in the chest and back.Ultrasound was used to ensure the intradermal delivery of injections and measure the dermal thickness.The minor iodine starch test was performed at baseline and 3 days,7 days,21 days,1 month,and 2 months after treatment.Results:All participants received intradermal injections.The dermis was thinner on the chest(thickness,0.20±0.03 cm)than on the back(thickness,0.39±0.07 cm)(P<0.05).An injection in the thicker dermis had a significantly smaller effective area at every follow-up visit.The drug concentration did not affect the effective area except at 3 days after treatment.Injection speed did not influence the effective area at any follow-up visits.Conclusion:An injection in a thicker dermis leads to a smaller effective area for intradermal injections.When the BoNTA dose is the same,the drug concentration and injection speed do not matter. 展开更多
关键词 Botulinum toxin type A Effective area Microbotulinum
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Characteristics and main controlling factors of intra-platform shoal thin-layer dolomite reservoirs:A case study of Middle Permian Qixia Formation in Gaoshiti-Moxi area of Sichuan Basin,SW China
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作者 HE Jiang LIAN Zhihua +5 位作者 LUO Wenjun ZHOU Hui XU Huilin HE Puwei Yang Yi LAN Xuemei 《Petroleum Exploration and Development》 SCIE 2024年第1期69-80,共12页
Based on the study of the distribution of intra-platform shoals and the characteristics of dolomite reservoirs in the Middle Permian Qixia Formation in the Gaoshiti–Moxi area of the Sichuan Basin,SW China,the control... Based on the study of the distribution of intra-platform shoals and the characteristics of dolomite reservoirs in the Middle Permian Qixia Formation in the Gaoshiti–Moxi area of the Sichuan Basin,SW China,the controlling factors of reservoir development were analyzed,and the formation model of“intra-platform shoal thin-layer dolomite reservoir”was established.The Qixia Formation is a regressive cycle from bottom to top,in which the first member(Qi1 Member)develops low-energy open sea microfacies,and the second member(Qi2 Member)evolves into intra-platform shoal and inter-shoal sea with decreases in sea level.The intra-platform shoal is mainly distributed near the top of two secondary shallowing cycles of the Qi2 Member.The most important reservoir rock of the Qixia Formation is thin-layer fractured-vuggy dolomite,followed by vuggy dolomite.The semi-filled saddle dolomite is common in fracture-vug,and intercrystalline pores and residual dissolution pores combined with fractures to form the effective pore-fracture network.Based on the coupling analysis of sedimentary and diagenesis characteristics,the reservoir formation model of“pre-depositional micro-paleogeomorphology controlling shoal,sedimentary shoal controlling dolomite,penecontemporaneous dolomite benefiting preservation of pores,and late hydrothermal action effectively improving reservoir quality”was systematically established.The“first-order high zone”micro-paleogeomorphology before the deposition of the Qixia Formation controlled the development of large area of intra-platform shoals in Gaoshiti area during the deposition of the Qi2 Member.Shoal facies is the basic condition of early dolomitization,and the distribution range of intra-platform shoal and dolomite reservoir is highly consistent.The grain limestone of shoal facies is transformed by two stages of dolomitization.The penecontemporaneous dolomitization is conducive to the preservation of primary pores and secondary dissolved pores.The burial hydrothermal fluid enters the early dolomite body along the fractures associated with the Emeishan basalt event,makes it recrystallized into medium–coarse crystal dolomite.With the intercrystalline pores and the residual vugs after the hydrothermal dissolution along the fractures,the high-quality intra-platform shoal-type thin-layer dolomite reservoirs are formed.The establishment of this reservoir formation model can provide important theoretical support for the sustainable development of Permian gas reservoirs in the Sichuan Basin. 展开更多
关键词 Middle Permian Qixia Formation intra-platform shoal thin-layer dolomite paleogeomorphology diagenesis Gaoshiti-Moxi area Sichuan Basin
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Ordovician reservoirs in Fuxian area:Gas accumulation patterns and their implications for the exploration of lower Paleozoic carbonates in the southern Ordos Basin
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作者 Ning Gu Juntao Zhang +2 位作者 Xiaohui Jin Fei Yang Lu Liu 《Energy Geoscience》 EI 2024年第1期63-71,共9页
In recent years,the Fuxian area in the southeastern Ordos Basin has undergone significant exploration,with industrial gas flow tested in wells drilled into the Ordovician marine carbonates.Despite this,the gas accumul... In recent years,the Fuxian area in the southeastern Ordos Basin has undergone significant exploration,with industrial gas flow tested in wells drilled into the Ordovician marine carbonates.Despite this,the gas accumulation patterns of this area are not fully understood,posing challenges for further exploration.Our analysis of geological conditions indicates that the Ordovician Majiagou Formation in this area hosts two gas plays:one found in weathering crusts and the other found in interior of the formation.We investigated various typical gas reservoirs in the area,focusing on differentiating the geological conditions and factors controlling gas accumulation in the weathering-crust and interior gas reservoirs.The results suggest three primary gas accumulation patterns in the Majiagou Formation in the Fuxian area:(1)upper gas accumulation in weathering crusts,present in the high parts of landforms such as residual paleo-hills or buried paleo-platform(Pattern I);(2)the stereoscopic pattern with gas accumulation in both weathering crusts and strata interior,arising in high parts of landforms such as residual paleo-hills or buried paleo-platforms(Pattern II);(3)lower gas accumulation in strata interior,occurring in the upper reaches and on both sides of paleo-trenches(Pattern III).This study will serve as a geological basis for future exploration deployment in the Fuxian area. 展开更多
关键词 Gas accumulation ORDOVICIAN Weathering crust play Interior play Fuxian area The ordos basin
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Efficiency evaluation and optimizing implementation strategy of green renovation market in existing residential areas in China
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作者 GUO Han-ding YANG Fan +1 位作者 QIN Guang-lei ZHANG Yin-xian 《Ecological Economy》 2024年第4期333-349,共17页
The key to the healthy development of the market for green renovation of existing settlements lies in effectively playing the role of market resource allocation,and scientific evaluation of the current market operatio... The key to the healthy development of the market for green renovation of existing settlements lies in effectively playing the role of market resource allocation,and scientific evaluation of the current market operation efficiency is a prerequisite for the optimization and adjustment of market operation.Based on the perspective of market operation effectiveness,we start from the connotation and significance of the evaluation of the operation efficiency of the market of green renovation of existing settlements,construct the evaluation index system of the operation efficiency of the market of green renovation of existing settlements,use the hierarchical analysis method(AHP)and fuzzy comprehensive evaluation method(Fuzzy),establish the fuzzy comprehensive evaluation model,and finally,based on the operation process reengineering,financing model innovation,service platform expansion and market environment improvement,it structures the operation improvement path of the green renovation market of existing settlements and promotes the orderly operation of the green renovation market of existing settlements. 展开更多
关键词 existing residential areas green renovation market operation efficiency evaluation upgrading paths
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Multi-scenario Simulation of the Impact of Land Use Change on the Ecosystem Service Value in the Suzhou-Wuxi-Changzhou Metropolitan Area,China
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作者 WANG Bin HU Chunguang ZHANG Yushuo 《Chinese Geographical Science》 SCIE CSCD 2024年第1期79-92,共14页
As the most economically developed metropolitan area in China’s Yangtze River Delta,the rapid changing land use patterns of Suzhou-Wuxi-Changzhou(Su-Xi-Chang) metropolitan area have profound impacts on the ecosystem ... As the most economically developed metropolitan area in China’s Yangtze River Delta,the rapid changing land use patterns of Suzhou-Wuxi-Changzhou(Su-Xi-Chang) metropolitan area have profound impacts on the ecosystem service value(ESV).Based on the patterns of land use change and the ESV change in Su-Xi-Chang metropolitan area from 2000 to 2020,we set up four scenarios:natural development scenario,urban development scenario,arable land protection scenario and ecological protection scenario,and simulated the impact of land use changes on the ESV in these scenarios.The results showed that:1) the area of built-up land in the Su-XiChang metropolitan area increased significantly from 2000 to 2020,and the area of other types of land decreased.Arable land underwent the highest transfer-out area,and was primarily converted into built-up land.The total ESV of Su-Xi-Chang metropolitan area increased initially then declined from 2000–2020,and the value of almost all individual ecosystem services decreased.2) Population density,GDP per area,night lighting intensity,and road network density can negatively impact the ESV.3) The total ESV loss under the natural development and urban development scenarios was high,and the expansion of the built-up land and the drastic shrinkage of the arable land contributed to the ESV decline under both scenarios.The total ESV under arable land protection and ecological protection scenarios increases,and therefore these scenarios are suitable for future land use optimization in Su-Xi-Chang.This study could provide a certain reference for land use planning and allocation,and offer guidance for the rational allocation of land resources. 展开更多
关键词 multiple scenarios land use simulation ecosystem service value(ESV) Patch-Generating Land Use Simulation(PLUS)model Suzhou-Wuxi-Changzhou(Su-xi-Chang)metropolitan area
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Planning and construction of Xiong’an New Area(city of over 5 million people):Contributions of China’s geologists and urban geology
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作者 Bo Han Zhen Ma +9 位作者 Liang-jun Lin Hong-wei Liu Yi-hang Gao Yu-bo Xia Hai-tao Li Xu Guo Feng Ma Yu-shan Wang Ya-long Zhou Hong-qiang Li 《China Geology》 CAS CSCD 2024年第3期382-408,共27页
China established Xiong’an New Area in Hebei Province in 2017,which is planned to accommodate about 5 million people,aiming to relieve Beijing City of the functions non-essential to its role as China’s capital and t... China established Xiong’an New Area in Hebei Province in 2017,which is planned to accommodate about 5 million people,aiming to relieve Beijing City of the functions non-essential to its role as China’s capital and to expedite the coordinated development of the Beijing-Tianjin-Hebei region.From 2017 to 2021,the China Geological Survey(CGS)took the lead in multi-factor urban geological surveys involving space,resources,environments,and disasters according to the general requirements of“global vision,international standards,distinctive Chinese features,and future-oriented goals”in Xiong’an New Area,identifying the engineering geologic conditions and geologic environmental challenges of this area.The achievements also include a 3D engineering geological structure model for the whole area,along with“one city proper and five clusters”,insights into the ecology and the background endowment of natural resources like land,geothermal resources,groundwater,and wetland of the area before engineering construction,a comprehensive monitoring network of resources and environments in the area,and the“Transparent Xiong’an”geological information platform that is open,shared,dynamically updated,and three-dimensionally visualized.China’s geologists and urban geology have played a significant role in the urban planning and construction of Xiong’an New Area,providing whole-process geological solutions for urban planning,construction,operation and management.The future urban construction of Xiong’an New Area will necessitate the theoretical and technical support of earth system science(ESS)from various aspects,and the purpose is to enhance the resilience of the new type of city and to provide support for the green,low-carbon,and sustainable development of this area. 展开更多
关键词 Low Carbon New City Planning and construction Land Geothermal resources Groundwater Wetland Underground space Geologic disasters Site stability Natural resource Ecosystem Geological safety Transparent xiong’an Resilient city xiong’an New area
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Dynamic Study on Soil Fungi Population in Artificial Vegetation Areas of Shapotou in Ningxia 被引量:10
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作者 窦彩虹 陈应武 《Agricultural Science & Technology》 CAS 2008年第3期145-148,共4页
[Objective] The changes of fungi in different soil layers and sand dunes of artificial vegetation areas in Ningxia Shapotou during different times were studied. [Method]The number of soil fungi in different soil layer... [Objective] The changes of fungi in different soil layers and sand dunes of artificial vegetation areas in Ningxia Shapotou during different times were studied. [Method]The number of soil fungi in different soil layers at same plot and in same soil layer at different plots were changed significantly.The quantitative distribution of fungi was the most in Cuiliugou but the fewest in quicksand among all soil types.[Result] The quantity of soil fungi in grasslands was varied in different soil layers at the same sample and in the same soil layer at different sample plots. The quantity of fungi from different soil types distributed mostly in Cuiliugou, a natural desert steppe, but little in quicksand. The species and quantity of fungi in CuiLiugou was the most in different types of sand-fixing lands. [Conclusion] The quantity of soil fungi in artificial vegetation areas raises with the increase of sand-fixing ages, The enhancement of vegetation construction and artificial management measures in inland is helpful for improving present situation of desertification. 展开更多
关键词 DESERT Artificial VEGETATION area FUNGI POPULATION
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Prediction of area burned under climatic change scenarios:A case study in the Great Xing'an Mountains boreal forest 被引量:7
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作者 杨光 邸雪颖 +3 位作者 曾涛 舒展 王超 于宏洲 《Journal of Forestry Research》 SCIE CAS CSCD 2010年第2期213-218,I0007,共7页
Monthly projections of maximum temperature,relative humidity,precipitation,and wind speed were made based on the model of HadCM3 and the climatic change scenarios of IPCC SRES A2a and B2a for the future scenario perio... Monthly projections of maximum temperature,relative humidity,precipitation,and wind speed were made based on the model of HadCM3 and the climatic change scenarios of IPCC SRES A2a and B2a for the future scenario periods of 2010–2039(referred to as 2020s),2040–2069(referred to as 2050s),and 2070–2099(referred to as 2080s).The period 1961–1990 was chosen as the baseline period.The observed and projected weather data were downscaled using delta change methods and historical relationships between weather data,area burned,and the seasonal severity rating(SSR) code of the Canadian Fire Weather Index System were examined.The variations of area burned as influenced by climate change were assessed quantitative and qualitative for the study region,assuming that the fire regimes had the similar responses to the warming climate as during the 20th century.Our results indicated that a linear regression relationship existing between the historical area burned and the mean SSR values with regression coefficient in the significant range of 0.16 to 0.61.It was evident that the increased SSR values could result in more area burned;the area burned in the study region would have an increasing pattern during the 21st century under scenarios A2a and B2a scenarios and the area burned would be doubled.Also,the future area burned would have a strong seasonal pattern that more fires would occur in summer and autumn fire season,especially in summer.The area burned in summer fire season would increase by 1.5 times compared to that in the baseline period in 2080s under A2a scenarios. 展开更多
关键词 climatic warming forest fire area burned FORECAST
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Study on the Forest Vegetation and Its Water and Soil Conservation Value in Fuxian Lake Drainage Area in Yunnan Province 被引量:5
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作者 艾建林 温庆忠 陶晶 《Meteorological and Environmental Research》 CAS 2010年第10期58-61,共4页
By using French SPOT5 satellite remote sensing image to contrast on the spot,the forest vegetation in Fuxian Lake basin was categorized into 23 forest types,6 vegetation subtypes,5 vegetation types,and the areas were ... By using French SPOT5 satellite remote sensing image to contrast on the spot,the forest vegetation in Fuxian Lake basin was categorized into 23 forest types,6 vegetation subtypes,5 vegetation types,and the areas were respectively calculated.The tree species structure and the coverage degree of every kind of forest vegetation were investigated,and the characteristics of forest vegetation were analyzed.The results showed that the soil conservation amount of forest in Fuxian Lake basin was 137.50×106 t/a,and the soil conservation value was 622.30×106 yuan/a.Moreover,the water source conservation value was 506.84×106 yuan/a. 展开更多
关键词 Fuxian Lake Forest vegetation area Soil conservation value Water source conservation value China
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The Comparison of Contents of Malondialdehyde and Proline in the Area of Karst Area in Northweastern Guangxi Province 被引量:6
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作者 覃勇荣 农艳春 +1 位作者 黄江滨 潘振兴 《Agricultural Science & Technology》 CAS 2011年第4期469-473,575,共6页
[Objective] To select excellent pioneer species of better ecological and economical comprehensive benefits from the common rock hill plants in Karst area in northwestern Guangxi Province.[Method] Determine the content... [Objective] To select excellent pioneer species of better ecological and economical comprehensive benefits from the common rock hill plants in Karst area in northwestern Guangxi Province.[Method] Determine the contents of malondialdehyde and proline in leaves of 65 strains of plants by thiobarbituric acid method and sultosalicylic acid method,analyze the relevance of the contents of malondialdehyde and proline by mathematics statistics and analyze the 65 kinds of rock hill plants by clustering [Result] The contents of malondialdehyde and proline are 0.005 2-0.038 1 μmol/g.There are comparably significant differences in the contents of malondialdehyde in different plants;The determination of proline contents in plant's leaves are 4.347-374.956 μg/ml.There are also significant differences in proline of different leaves of rock hill plants.The contents of malondialdehyde and proline can be used as a reference point in selecting pioneer plants in Karst area.But when we select the pioneer plants,not only the biological characters of the species themselves should be taken into consideration,but also the differences of Karst area environment,ecological and biological benefits and the reasonable distribution of species.[Conclusion] Pistacia chinensis,Zenia insignis,Acacia confusa,Itoa orientalis and Sophora japonica can be used as the first choices of excellent pioneer plants in Karst area in northwestern area which comparably consists with the real situation of afforestation of rock hills and recovery of plants in Guangxi. 展开更多
关键词 Northwestern of Guangxi Karst area Rock hills plants MALONDIALDEHYDE PROLINE
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Research on Leisure Agriculture Development Based on Red Tourist Area in Ningxiang County of Hunan Province,China 被引量:1
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作者 刘天曌 杨载田 王盛强 《Journal of Landscape Research》 2011年第6期37-41,共5页
Based on development of leisure agriculture in Ningxiang County,the existing problems had been analyzed,conditions for leisure agriculture development in Ningxiang County had been summarized,which included good natura... Based on development of leisure agriculture in Ningxiang County,the existing problems had been analyzed,conditions for leisure agriculture development in Ningxiang County had been summarized,which included good natural conditions and abundant leisure agricultural resources;advantageous social economic conditions and excellent transportation,reference from domestic and foreign leisure agriculture.In view of these advantages,development conception had been further proposed and it was considered that it should enhance publicity,build brand and cultivate source market of leisure agriculture;conduct scientific decision and reasonable planning,develop leisure agricultural tourist area at suburb;pay attention to ecology,protect environment and walk sustainable development road.As for leisure agriculture in Ningxiang,four tourist areas should be divided,which were suburban rest tourist area in the north,celebrity hometown tourist area in the east,hot spring recuperation vacation area in the south and landscape religious tourist area in the west. 展开更多
关键词 Ningxiang COUNTY RED TOURIST area LEISURE AGRICULTURE
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Reflection on Rural Settlement Environmental Landscape of Mixed Living Areas of Multination in Xinjiang Province of China——A Case Study of Wuchang Region 被引量:1
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作者 王小冬 张旭 《Journal of Landscape Research》 2012年第2期45-46,50,共3页
As Xinjiang rural settlement planning has only paid attention to the completion of basic community functions but neglected landscape planning and shaping,strategies for sustainable development have been proposed by ta... As Xinjiang rural settlement planning has only paid attention to the completion of basic community functions but neglected landscape planning and shaping,strategies for sustainable development have been proposed by taking rural settlement landscape construction in mixed living areas of Wuchang for example.It should well deal with problems about nationalities and religious belief,solve the contradiction between traditional life and production mode and modern standardized agricultural life and production mode,promote the maximization of settlement landscape function,coordinate the relation between settlement landscape and natural environment,make settlement landscape correspond with traditional geomancy,construct definite landscape position and create regional landscape feature.Finally,in view of the design and renovation of settlement landscape,it has proposed respecting local natural geological condition,respecting current settlement pattern and layout,avoiding rebuilding new villages,and founding a"Settlement Landscape Construction and Development Autonomous Committee". 展开更多
关键词 MIXED LIVING areas Rural SETTLEMENT ENVIRONMENTAL LANDSCAPE REFLECTION
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Research on Beautiful Countryside Planning in Underdeveloped Areas from Perspective of Traditional and Modern Integration——a Case Study of Jiangjia Village, Jishui County, Jiangxi Province 被引量:2
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作者 李小云 胡思琦 《Agricultural Science & Technology》 CAS 2016年第6期1468-1470,共3页
In context of building beautiful countryside nationwide, underdeveloped areas are confronted by many problems, such as monotonous industry structure, simi- lar rural landscape and loss of characteristics. With a case ... In context of building beautiful countryside nationwide, underdeveloped areas are confronted by many problems, such as monotonous industry structure, simi- lar rural landscape and loss of characteristics. With a case of Jiangjia Village, Jishui County, Jiangxi Province, the research explored rural pattern, cultural characteristics, building style, development value and potential and analyzed regional cooperation, urban-rural integration, and planning first, from the perspectives of economy, culture and building in order to protect traditional economy and highlight local characteristics. 展开更多
关键词 Tradition and modern INTEGRATION Underdeveloped areas Beautiful Countryside
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Study on Ecological Folklore Tourism Development of Xi'an Chanba River Ecological Area 被引量:1
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作者 尹得举 叶苹 《Journal of Landscape Research》 2009年第3期1-5,11,共6页
Taking the folklore tourism planning of Chanba River ecological area as the study object and aiming at problems in the development of folklore tourism in Xi'an, the planning technique of 'visualizing the intan... Taking the folklore tourism planning of Chanba River ecological area as the study object and aiming at problems in the development of folklore tourism in Xi'an, the planning technique of 'visualizing the intangible culture' was adopted in this study from the perspective of ecological folk-custom based on summarizing the characteristics of folk-custom tourism resources in the planning area, which discussed development ideas and strategies of the ecological folk-custom tourism resources to achieve a sustainable development of ecological folklore tourism development of Chanba River ecological area. 展开更多
关键词 Chanba River ECOLOGICAL area ECOLOGICAL folk-custom FOLKLORE TOURISM DEVELOPMENT strategy Sustainable DEVELOPMENT
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Prediction of Maize Yield and Its Component Factors in Yellow River Irrigation Area of Ningxia under Climate Change 被引量:1
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作者 刘玉兰 任玉 +1 位作者 王迎春 郭晓雷 《Agricultural Science & Technology》 CAS 2011年第5期699-701,736,共4页
[Objective] The aim was to quantitatively predict the variation trend of maize yield in Yellow River irrigation area of Ningxia under future climate change scenarios.[Method] Based on the data of daily temperature,pre... [Objective] The aim was to quantitatively predict the variation trend of maize yield in Yellow River irrigation area of Ningxia under future climate change scenarios.[Method] Based on the data of daily temperature,precipitation and radiation in 25 km × 25 km grid in Ningxia from 2010 to 2100 obtained by regional climate model,maize yield in Yellow River irrigation area of Ningxia in the 21st century was studied by means of corrected CERES-Maize model.[Result] With climate warming,maize yield in Yellow River irrigation area of Ningxia in 2020s and 2050s showed increase trend compared with base years(average in 1961-1990)when current adaptive maize variety and optimum production management measures were adopted,while maize yield went down in 2080s with the further increase of temperature.The grain number per spike and spike grain weight as the yield components of maize also showed the same trend with maize yield.In 2020s and 2050s,the increase of maize yield under B2 scenario was higher than that under A2 scenario,while the decrease of maize yield under B2 scenario was lower than that under A2 scenario in 2080s.[Conclusion] With the increase of temperature,maize yield in Yellow River irrigation area of Ningxia went up firstly and then went down. 展开更多
关键词 Yellow River irrigation area of Ningxia Climate change MAIZE
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Analysis on Strategic Future of Application of Agricultural Ecological Source in Control on Agricultural Nonpoint Source Pollution in Xi River Area in Guangxi 被引量:1
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作者 刘永贤 《Agricultural Science & Technology》 CAS 2016年第1期201-203,共3页
Non-point source pollution has become a hot issue on aquatic ecological environment at home and abroad. The research analyzed the challenges confronted by Xi River and proposed to construct agricultural ecological sou... Non-point source pollution has become a hot issue on aquatic ecological environment at home and abroad. The research analyzed the challenges confronted by Xi River and proposed to construct agricultural ecological source in middle and upper reaches of the Xi River from the perspectives of scientific layout, legal construction, routine monitoring, technology integration, and coordination system in order to promote sustainable development of eco-environment in Xi River. 展开更多
关键词 Nonpoint source pollution Agriculture Aquatic environment xi River basin Agricultural ecological source
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Analysis of results related to the percent free prostate specific antigen among men without prostate diseases in Xi'an area
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作者 Peng Zhang Ziming Wang +1 位作者 Tie Chong Lihua Zhao 《Journal of Nanjing Medical University》 2007年第1期25-28,共4页
To measure the percent of free prostate specific antigen (fPSA) among men without prostate diseases in Xi'an area, and to study the relationship of percent fPSA with age and pathological grade, clinical stage of pr... To measure the percent of free prostate specific antigen (fPSA) among men without prostate diseases in Xi'an area, and to study the relationship of percent fPSA with age and pathological grade, clinical stage of prostate cancer (PCa) with percent fPSA, and to analyze the difference between the data in China and the.overseas data to determine appropriate reference range for Chinese male. Methods: A total of 713 participants were enrolled into the study, with PSA, fPSA in serum measured and the percent fPSA calculated. Out of 713 cases, 679 without prostate diseases were divided into 5 groups by age, and then the relationships of PSA, fPSA and percent fPSA with age were studied, respectively. The relationship of pathological grade and clinical stage with percent fPSA of the 34 participants with PCa was also studied. With the help of the related data of men without prostate disease, the appropriate reference range for Chinese male was established. Results: The increases in PSA or fPSA were correlated with age, while there was no significant correlation between age and percent fPSA. The percent fPSA was also correlated with pathological grade and clinical stage of PCa. The percent fPSA of men without prostate disease in Xi'an area was significandy lower than that in the related overseas data. The reference range of percent fPSA for Chinese male was≥ 15%. Conclusion: Percent fPSA might be more useful than PSA in the detection of prostate cancer. As the percent fPSA is decreased, the pathological grade is decreased, and the clinical stage is increased, the malignant degree is increased. The reference range of ≥15% is more appropriate for Chinese male. 展开更多
关键词 percentage free prostate specific antigen prostate cancer Age RELATIVITY reference range xi'an area
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Analysis of the Maximum Consecutive Precipitation Variation in Liaoning Artificial Precipitation Test Area
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作者 杨旭 高杰 +3 位作者 杨青 田广元 陈刚 胡伟 《Meteorological and Environmental Research》 CAS 2010年第9期46-47,96,共3页
According to the daily precipitation data in artificial precipitation season during May to September from 1961 to 2008 in Liaoning Province,the maximum consecutive precipitation in the artificial precipitation test ar... According to the daily precipitation data in artificial precipitation season during May to September from 1961 to 2008 in Liaoning Province,the maximum consecutive precipitation in the artificial precipitation test area is studied based on the maximum consecutive precipitation from May to September in 48 years.The results shows that the period of maximum consecutive precipitation in each month is different,and the variance trends of maximum consecutive precipitation in May,July,August and September are decreasing,while the variance trend of maximum consecutive precipitation in June is increasing. 展开更多
关键词 Artificial precipitation test area Maximum consecutive precipitation Variation analysis China
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Proposal of Landscape Space Transfer Index and Changes of Landscape Area Based on Transfer Matrix——With Yutian County in Xinjiang as a Study Case
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作者 贺凌云 海米提.依米提 蔡永革 《Journal of Landscape Research》 2010年第7期26-29,共4页
The most significant changes of landscape in a certain period are landscape area changes and spatial changes of landscape patches.Based on transfer matrix and total amount change of landscape area,landscape space tran... The most significant changes of landscape in a certain period are landscape area changes and spatial changes of landscape patches.Based on transfer matrix and total amount change of landscape area,landscape space transfer index and landscape area change index were established,and then applied to analyze plain oasis and desert in Yutian County,Xinjiang Uyghur Nationality Autonomous Region,the results showed that landscape space transfer in this region was drastic,but total landscape area changed only slightly,thus space transfer index was much higher than area change index,which indicated that landscapes in arid area were given with particular spatial undulant features and sensitivity,while man-made landscapes(artificial oasis) are stable and expanding to some extent.With landscape space transfer index as the comprehensive indicator,space transfer intensity of landscape within a certain period can be demonstrated,which is favorable for the comparison of landscape change intensity among different types and within different periods,in addition,some macroscopic change features of landscapes can also be reflected by comprehensively analyzing landscape space transfer index and landscape area change index. 展开更多
关键词 ARID area LANDSCAPE Space TRANSFER INDEX area change INDEX
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