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Geographical Indications and Regional Public Brands of the Whole Rice Industry Chain in the Yangtze River Economic Belt
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作者 Min ZHANG Li GAO +2 位作者 Dongjing LI Juncheng ZHU Bin HU 《Asian Agricultural Research》 2025年第1期1-13,共13页
The Yangtze River Economic Belt is the main rice producing area in China.The rice industry chain is the agricultural pillar industry chain of this economic belt and it is the key to ensuring national food security and... The Yangtze River Economic Belt is the main rice producing area in China.The rice industry chain is the agricultural pillar industry chain of this economic belt and it is the key to ensuring national food security and promoting comprehensive rural revitalization.This study discusses the entire rice industry chain in the Yangtze River Economic Belt from the national rice production functional zones,agricultural product quality and safety,national famous and excellent new agricultural products,national specialty agricultural products,"China s good grain and oil"products,and national advantageous characteristic industrial clusters.Then,it discusses the geographical indications of rice and its products in this economic belt from geographical indication products,geographical indication trademarks,agricultural geographical indications,geographical indication standards,geographical indication special indications,national geographical indication product protection demonstration zones,and Chinese geographical indication products protected by the European Union.In addition,it analyzes the five main problems between geographical indications and public brands,such as the limited use of geographical indication specific signs and the imperfect intellectual property protection system for geographical indications.Finally,it proposes eight strategies,including promoting the high-quality development of the entire rice industry chain,creating a geographical indication regional public brand for rice and its products,and implementing geographical indication protection projects. 展开更多
关键词 Yangtze River Economic Belt Rice and its products Entire industry chain geographical indication Regional public brand
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Geographical Variation in the Advertisement Calls of Leptobrachella ventripunctata(Anura:Megophryidae)in Southwestern China
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作者 Chaobo FENG Tuo SHEN +4 位作者 Lang MU Jing LIU Shize LI Yixin DIAO Haijun SU 《Asian Herpetological Research》 SCIE CSCD 2024年第3期140-151,共12页
In anurans,advertisement calls(ACs)are an essential form of intraspecific communication.This study evaluates geographical variation in the ACs of Leptobrachella ventripunctata in the Guizhou Plateau,southwestern China... In anurans,advertisement calls(ACs)are an essential form of intraspecific communication.This study evaluates geographical variation in the ACs of Leptobrachella ventripunctata in the Guizhou Plateau,southwestern China,and explores correlations between call characteristics,body size,and environmental factors.ACs are simple calls of L.ventripunctata,and apparent differences were observed in the ACs among different geographical populations of L.ventripunctata.The Call duration(CD)revealed a significant positive correlation with altitude and a significant negative correlation with temperature and humidity.Moreover,the Dominant frequency(DF)exhibited a significant negative correlation with altitude and the habitat closure degree and a significant positive correlation with temperature.These variations in ACs between different geographical populations of L.ventripunctata may critically impact the adaptive evolution of species,and the calls may also be relevant for environmental selection. 展开更多
关键词 ANURAN BIOACOUSTICS environmental factors geographical divergence
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Geographically and Temporally Weighted Regression in Assessing Dengue Fever Spread Factors in Yunnan Border Regions
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作者 ZHU Xiao Xiang WANG Song Wang +3 位作者 LI Yan Fei ZHANG Ye Wu SU Xue Mei ZHAO Xiao Tao 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2024年第5期511-520,共10页
Objective This study employs the Geographically and Temporally Weighted Regression(GTWR)model to assess the impact of meteorological elements and imported cases on dengue fever outbreaks,emphasizing the spatial-tempor... Objective This study employs the Geographically and Temporally Weighted Regression(GTWR)model to assess the impact of meteorological elements and imported cases on dengue fever outbreaks,emphasizing the spatial-temporal variability of these factors in border regions.Methods We conducted a descriptive analysis of dengue fever’s temporal-spatial distribution in Yunnan border areas.Utilizing annual data from 2013 to 2019,with each county in the Yunnan border serving as a spatial unit,we constructed a GTWR model to investigate the determinants of dengue fever and their spatio-temporal heterogeneity in this region.Results The GTWR model,proving more effective than Ordinary Least Squares(OLS)analysis,identified significant spatial and temporal heterogeneity in factors influencing dengue fever’s spread along the Yunnan border.Notably,the GTWR model revealed a substantial variation in the relationship between indigenous dengue fever incidence,meteorological variables,and imported cases across different counties.Conclusion In the Yunnan border areas,local dengue incidence is affected by temperature,humidity,precipitation,wind speed,and imported cases,with these factors’influence exhibiting notable spatial and temporal variation. 展开更多
关键词 Dengue fever Meteorological factor geographically and temporally weighted regression
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Species’ geographical range, environmental range and traits lead to specimen collection preference of dominant plant species of grasslands in Northern China
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作者 Jingya Zhang Cui Xiao +5 位作者 Xiaoyu Duan Xin Gao Hao Zeng Rong'an Dong Gang Feng Keping Ma 《Plant Diversity》 SCIE CAS CSCD 2024年第3期353-361,共9页
Many different factors,such as species traits,socio-economic factors,geographical and environmental factors,can lead to specimen collection preference.This study aims to determine whether grassland specimen collection... Many different factors,such as species traits,socio-economic factors,geographical and environmental factors,can lead to specimen collection preference.This study aims to determine whether grassland specimen collection in China is preferred by species traits(i.e.,plant height,flowering and fruiting period),environmental range(i.e.,the temperature and precipitation range)and geographical range(i.e.,distribution range and altitudinal range).Ordinary least squares models and phylogenetic generalized linear mixed models were used to analyze the relationships between specimen number and the explanatory variables.Random Forest models were then used to find the most parsimonious multivariate model.The results showed that interannual variation in specimen number between 1900 and 2020 was considerable.Specimen number of these species in southeast China was notably lower than that in northwest China.Environmental range and geographical range of species had significant positive correlations with specimen number.In addition,there were relatively weak but significant associations between specimen number and species trait(i.e.,plant height and flowering and fruiting period).Random Forest models indicated that distribution range was the most important variable,followed by flowering and fruiting period,and altitudinal range.These findings suggest that future floristic surveys should pay more attention to species with small geographical range,narrow environmental range,short plant height,and short flowering and fruiting period.The correction of specimen collection preference will also make the results of species distribution model,species evolution and other works based on specimen data more accurate. 展开更多
关键词 Biological specimen Collection preference Dominant plant species Environmental range geographical range Species traits
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Measures of Geographical Accessibility to Healthcare in Bougouni Health District in Mali
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作者 Sidiki Traoré 《Revue Internationale de Géomatique》 2024年第1期167-182,共16页
In Mali,access to healthcare is a major concern.It has been a national priority since the Alma-Ata Declaration in 1978.Since then,major efforts have been made by the State and its partners to achieve this objective.Th... In Mali,access to healthcare is a major concern.It has been a national priority since the Alma-Ata Declaration in 1978.Since then,major efforts have been made by the State and its partners to achieve this objective.These efforts appear insufficient in the Bougouni health district,wheremore than half the population is still far frombasic health services.Given this situation,it is essential to assess geographical accessibility to healthcare to identify the localities that have been left behind,hence the purpose of this research in the Bougouni District.Three types of data were used:the size of the population,the location of community health centers and the road network.Two consecutive stages summarize the approach used,the improved two-stage floating attraction area method(E2SFCA)was used to measure the spatial dimension of accessibility to health services.It was supplemented by spatial autocorrelation analyses,particularly the local Moran index,to detect clusters of localities with low or high spatial accessibility values.The results reveal strong spatial disparities in access to primary healthcare within and between communes and at the same time call into question the effectiveness of the policy of geographical coverage of the population in terms of basic healthcare.They also highlight the demographic pressure on existing health services and suggest ways of significantly improving geographical access to health services. 展开更多
关键词 Spatial accessibility INEQUALITY MALI HEALTH geographic information system
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Cluster Analysis of Morphologic Characteristic of Eight Geographical Populations of Rana Dybowskii 被引量:1
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作者 应璐 徐艳春 +2 位作者 黄孝明 田秀华 汪青雄 《Agricultural Science & Technology》 CAS 2008年第1期104-106,110,共4页
[ObJective] The research aimed to determine the geographic distribution map of system of Rana dybowskii. [Method] Four morphologic indices (body length, body weight, forelimb length, hindlimb length) of eight geogra... [ObJective] The research aimed to determine the geographic distribution map of system of Rana dybowskii. [Method] Four morphologic indices (body length, body weight, forelimb length, hindlimb length) of eight geographical populations of R.dybowskii which naturally distribute in Changhai Mountain and Xiaoxing'an Mountain were measured. Measure results were variance analyzed and cluster analyzed. [Result] Variance analysis showed: the genetic branching among the Dongfanghong male population( belongs to Wandashan) and Xiaoxing'an Mountain male population and Changbai Mountain male population were significantly different (P〈0.05) ; the genetic branching between the Hebei female population (belongs to Xiaoxing'an Mountain) and Changbai Mountain female population was significantly different (P〈0.05 ). Cluster analysis showed : male R.dybowskii can be divided into three groups : the first group included Quanyang, Tianbei, Chaoyang and Ddkouqin, the second group included Tieli and Anshan, the third group included Dongfanghong; and the female R. dybowskii can be divided into three groups : the first group included Quanyang and Chaoyang, the second group included Tianbei and Dakouqin, the third group included Hebei. [Condusion] The paper deduced that the Sanjiang Plain was the geographical origin center ofR. dybowskii which radiated to Changbai Mountain and Xiaoxing'an Mountain along the adverse current of Songhua River basin, therefore, the current distribution pattern of R. dybowskii was formed. 展开更多
关键词 Rana dybowskii geographical population Morphologic characteristic Distribution pattern geographical origin Cluster analysis
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Research on Geographical Environment and Culture Symbiosis of Chishui River Basin 被引量:1
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作者 王爱华 彭恩 《Journal of Landscape Research》 2011年第11期81-85,共5页
This paper took Chishui River Basin as the research object,and pointed out that its culture,which reflected local life and production and was featured with regional characteristics as well as abundant cultural connota... This paper took Chishui River Basin as the research object,and pointed out that its culture,which reflected local life and production and was featured with regional characteristics as well as abundant cultural connotation,was constituted by native natural and cultural geography,folk customs and historical feature.The relation between Chishui salt path and salt business culture under the typical closed and half-closed geographical environment was analyzed to indicate that the realignment of Chishui River had brought prosperity of Chishui River,booming of commercial towns,and development of ancient architectures and guild hall culture.The relation between rich natural resources and production and life culture of Chishui River was explained to show that Danxia landform nurtured stone culture,Chishui River resources cultivated fishing culture,special hydrogeological environment fostered liquor culture represented by Maotai,and Bamboo culture accumulated for hundreds of years.Finally,it introduced military culture and the spirit of the Long March forming based on the special location of Chishui River.It emphasized that geological environment was the important basis for human's survival and played an immeasurable role in the cultural development of a region. 展开更多
关键词 Chishui RIVER BASIN CULTURE geographical ENVIRONMENT SYMBIOSIS
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Research on Geographical Indications and Cultural Heritage of Famous Tea in Hubei 被引量:1
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作者 孙志国 黄莉敏 +2 位作者 熊晚珍 王树婷 钟学斌 《Agricultural Science & Technology》 CAS 2012年第3期502-506,536,共6页
In the study, analysis was made on present situation and development measures of geographical indications and cultural heritage protection of famous teas in Hubei Province. In addition, 8 related suggestions were prop... In the study, analysis was made on present situation and development measures of geographical indications and cultural heritage protection of famous teas in Hubei Province. In addition, 8 related suggestions were proposed as well. 展开更多
关键词 TEA geographical indication Cultural heritage Tangible cultural heritage Intangible cultural heritage Hubei Province
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Exploration of the spatial pattern of urban residential land use with geographically weighted regression technique: a case study of Nanjing,China 被引量:1
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作者 胡明星 吴江 朱选 《Journal of Southeast University(English Edition)》 EI CAS 2015年第1期149-156,共8页
As the traditional methods and technical means cannot meet the quantitative research needs of the urban land use patterns, quantitative research methods for the urban land use pattern are established via the GIS (geo... As the traditional methods and technical means cannot meet the quantitative research needs of the urban land use patterns, quantitative research methods for the urban land use pattern are established via the GIS (geographic information system ) technique combined with the related theories and models. Taking the city of Nanjing as an example, a spatial database of urban land use and other environmental and socio-economic data is constructed. A multiple linear regression model is developed to determine the statistically significant factors affecting the residential land use distributions. To explain the spatial variations of urban land use patterns, the geographically weighted regression (GWR) is employed to establish spatial associations between these significant factors and the distribution of urban residential land use. The results demonstrate that the GWR can provide an effective approach to the exploration of the urban land use spatial patterns and also provide useful spatial information for planning residential development and other types of urban land use. 展开更多
关键词 urban residential land use GIS geographic information system) multiple linear regression geographically weighted regression
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Analysis of the Correlation between the Geographical Distribution of Populus euphratica Oliv. and the Climatic Environment
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作者 杨银科 阎正龙 《Agricultural Science & Technology》 CAS 2012年第7期1450-1455,共6页
[Objective] This research was to study the correlation regional climatic characteristics and changing geographic distribution of Populus euphratica Oliv. (Salicaceae), as well as the adaption of Populus euphratica Oli... [Objective] This research was to study the correlation regional climatic characteristics and changing geographic distribution of Populus euphratica Oliv. (Salicaceae), as well as the adaption of Populus euphratica Oliv. to the climatic environment. [Method] The climatic characteristics, water source, groundwater and soil type in the distribution regions of Populus euphratica Oliv. and the effect of long-term human activities were comprehensively analyzed based an overview of Populus euphratica Oliv. and its distribution. [Result] Specific regional climatic characteristics and long term human activities are the principle determinants for the growth of Populus euphratica Oliv. The change of leaf shape is a distinct feature of Populus euphratica Oliv. in adapting to the climatic environment. Populus euphratica Oliv. withstands various environmental stresses by means of in vivo synthesis, transport and conversion of secondary phenolic metabolites. Effective protection and rehabilitation measures, and ecological water transport have obvious effect on the restoration and reconstruction of damaged ecological environment of Populus euphratica oasis. [Conclusion] This study is of great significance for the restoration of ecological environment in the arid inland regions, north-west China. 展开更多
关键词 POPULUS EUPHRATICA Oliv. (Salicaceae) geographic distribution Climatic and environmental characteristics CORRELATION ANALYSIS
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Geographical history的概念和汉译——兼论Alan R.H.Baker地理历史学思想 被引量:1
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作者 孙俊 潘玉君 《中国科技术语》 2012年第5期23-29,共7页
针对国内将贝克的geographical history一词译为"地理学史"或"地理史"的问题,结合他的新作对geographical history这一术语的论述及学科合法地位的诉求,认为应译为"地理历史学"。同时结合国内学者对"... 针对国内将贝克的geographical history一词译为"地理学史"或"地理史"的问题,结合他的新作对geographical history这一术语的论述及学科合法地位的诉求,认为应译为"地理历史学"。同时结合国内学者对"地理历史学"的术语混乱和学科诉求做了论述,分析了"地理历史学"术语混乱的部分原因。认为对国内外"地理历史学"思想应给予注意,给予"地理历史学"一个合法的学科地位。 展开更多
关键词 地理历史学 国内认同
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Geographical Patterns and Temporal Variations of Regional Dry and Wet Heatwave Events in China during 1960–2008 被引量:32
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作者 丁婷 钱维宏 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2011年第2期322-337,共16页
Daily maximum/minimum temperatures and relative humidity records from 510 stations in China for the period 1960–2008 were used to investigate geographical patterns and temporal variations of heatwave (HW) events. D... Daily maximum/minimum temperatures and relative humidity records from 510 stations in China for the period 1960–2008 were used to investigate geographical patterns and temporal variations of heatwave (HW) events. Dry and wet HW events were compared by different definitions. Regionally, both dry and wet HW events are commonly located in southeastern China in the monsoon area, with neither type occurring in the northeast part of Northeast China and Southwest China, while the north-northwest region of the country experiences dry HW events and a few wet HW events. In the southeast of the country, site dry HW events occurred from April to September and mostly in June, while site wet HW events occurred from April to October and mostly in September. In total, 163 regional wet HW events were identified. The ten longest regional wet HW events lasted for more than 20 days, while the mean duration for 163 events was about 11 days. For the top ten events, six occurred after the 1990s, compared with four before this time. Global surface warming was clear since 1979, but the frequency and severity of regional wet HW events were relatively low in the 1980s, increasing remarkably since the 1990s. Possible reasons for this might be the strong interdecadal and interannual variations in regional atmospheric circulations, as well as water transport related directly to temperature contrasts in different regions, rather than global-mean temperature changes. 展开更多
关键词 climate extreme HEATWAVE geographical pattern temporal variation China
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Rice cultivation changes and its relationships with geographical factors in Heilongjiang Province,China 被引量:8
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作者 LU Zhong-jun SONG Qian +4 位作者 LIU Ke-bao WU Wen-bin LIU Yan-xia XIN Rui ZHANG Dong-mei 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2017年第10期2274-2282,共9页
Rice planting patterns have changed dramatically over the past several decades in northeast China (NEC) due to the combined influence of global change and agricultural policy. Except for its great implications for e... Rice planting patterns have changed dramatically over the past several decades in northeast China (NEC) due to the combined influence of global change and agricultural policy. Except for its great implications for environmental protection and climate change adaption, the spatio-temporal changes of rice cultivation in NEC are not clear. In this study, we conducted spatio-temporal analyses of NEC's major rice production region, Heilongjiang Province, by using satellite-derived rice cultivation maps. We found that the total cultivated area of rice in Heilongjiang Province increased largely from 1993 to 2011 and it expanded spatially to the northern and eastern part of the Sanjiang Plain. The results also showed that rice cultivation areas experienced a larger increase in the region managed by the Reclamation Management Bureau (RMB) than that managed by the local provincial government. Rice cultivation changes were closely related with those geographic factors over the investigated periods, represented by the geomorphic (slope), climatic (accumulated temperature), and hydrological (watershed) variables. These findings provide clear evidence that crop cultivation in NEC has been modified to better cope with the global change. 展开更多
关键词 paddy rice spatio-temporal change cultivation area geographical factors
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PROGRESS IN STUDIES ON GEOGRAPHICAL ENVIRONMENTS OF THE QINGHAI-XIZANG PLATEAU 被引量:2
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作者 郑度 李炳元 《Chinese Geographical Science》 SCIE CSCD 1999年第4期2-9,共8页
The Qinghai Xizang (Tibet) Plateau area was subjected to twice uplift and planation in the Tertiary. Intense uplifting of the plateau area has given rise to drastic changes and differentiation of physical environment ... The Qinghai Xizang (Tibet) Plateau area was subjected to twice uplift and planation in the Tertiary. Intense uplifting of the plateau area has given rise to drastic changes and differentiation of physical environment on the plateau and the surrounding area since 3.4 Ma B.P. Significant environmental changes with dry tendency in interior of the plateau had occurred during the last 150 ka B.P. By comparative study on several mountains of the plateau, two systems of the structure type of the altitudinal belt are identified and nine groups are subdivided . A distribution model with close relevance to highland uplift effect has been generalized. A number of striking geo ecological phenomena and their spatial pattern such as moisture corridor, dry valleys, high cold meadow zone, and high cold arid core area are investigated and discussed. Based on the thermal conditions, moisture regimes and variation in landforms of the plateau is sequentially demarcated. A tentative scheme of 2 temperature belts, 10 natural zones and 28 physical districts has been proposed not including southern slopes of the East Himalayas. The Qinghai Xizang Plateau is sensitive to “green house effect”, showing close relation with global change. Characteristics of temperature and precipitation on the plateau during the last 2000 years, and response of glaciers, snow deposit and permafrost on the plateau to global change are dealt with in the present paper. 展开更多
关键词 QINGHAI Xizang PLATEAU geographical environment palaeo geographical evolution ENVIRONMENTAL DIFFERENTIATION
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The evolution of tea spatial agglomeration in China:An analysis based on different geographical scales 被引量:4
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作者 LIU Han-chu FAN Jie +1 位作者 ZENG Yu-xi WANG Wen-zhao 《Journal of Mountain Science》 SCIE CSCD 2018年第12期2590-2602,共13页
The spatial agglomeration of agricultural production is conducive to reducing planting costs, increasing production efficiency and improving product quality. It is an important way to promote the transformation and up... The spatial agglomeration of agricultural production is conducive to reducing planting costs, increasing production efficiency and improving product quality. It is an important way to promote the transformation and upgrad of tea industry and realize the modernization of China's tea industry. This study used Gini coefficient and spatial autocorrelation analysis to explore the characteristics of tea spatial agglomeration in China from three geographical scales: regional level, provincial level and prefecture level from the year 2005 to 2015. The results indicated that there was a significant scale effect on the tea spatial agglomeration. The agglomeration degree increased from the regional level, provincial level to prefecture level. The types of spatial agglomeration evolution of the three scales were Ushaped, continuous diffusion, and continuous agglomeration. The spatial autocorrelation of tea production could only be found at the prefecture level. Meanwhile, at the prefecture scale, we could not only reveal the pattern changes at the regional and provincial levels, but also identify tea production agglomeration regions. Compared with the large scale, the small scale could reveal the characteristics of tea spatial agglomeration in more details. Factors such as natural resource endowments, cost factor, technological advancement, agglomeration economy, and agricultural policy influenced the evolution of tea spatial agglomeration from different geographical scales. Finally, from the perspectives of spatial transfer of tea production, promoting spatial agglomeration, building tea production bases, and breaking administrative boundaries, we proposed several policy suggestions for optimizing the spatial layout of tea production. 展开更多
关键词 TEA production Spatial AGGLOMERATION geographIC SCALE Driving FACTORS China
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Quantification of driving factors on NDVI in oasis-desert ecotone using geographical detector method 被引量:4
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作者 ZHANG Yu ZHANG Ke-cun +1 位作者 AN Zhi-shan YU Yan-ping 《Journal of Mountain Science》 SCIE CSCD 2019年第11期2615-2624,共10页
Within oasis-desert ecotone regions,the normalized difference vegetation index(NDVI)is an important parameter for evaluating the growth of vegetation.An accurate quantitative study between NDVI and environmental and a... Within oasis-desert ecotone regions,the normalized difference vegetation index(NDVI)is an important parameter for evaluating the growth of vegetation.An accurate quantitative study between NDVI and environmental and anthropogenic factors is critical for understand the driving factors of vegetation growth in oasis-desert ecotone.In 2016,four periods Landsat 8 OLI_TIRS images,relevant climatological parameters data(air temperature,air relative humidity,wind velocity and accumulated temperature),land cover type data and soil data were selected as proxies.In order to quantify the explanatory power for NDVI spatial and temporal distribution in the southern edge of Dunhuang City and northern side of the Mingsha Mountain,the geographical detector model was used to explain the potential influences of factors versus the spatial distribution of NDVI,and each explanatory variable's relative importance can be calculated.The factor detector results disclose that the spatial distribution of NDVI is primarily dominated by land cover type.The risk detector results show that,high NDVI region is located within woodland.The mean value of NDVI displays an increase and then decrease trend with air temperature increase.With the increase of wind velocity and decrease of air relative humidity,the NDVI value shows a decrease trend.The interactive q values between the two factors are higher than any q value of separated factors.Results also indicate that the strongest interactive effects of NDVI are different in distinct seasons.Consequently,anthropogenic activity is more important than environmental factors on NDVI in oasis-desert ecotone.We also demonstrate that air relative humidity rather than air temperature have played a greater role in NDVI spatial distribution. 展开更多
关键词 Influence factors Normalized DIFFERENCE VEGETATION index geographical DETECTOR Oasis-desert ECOTONE
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Geographical Variation and Influencing Factors of Spartina alterniflora Expansion Rate in Coastal China 被引量:5
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作者 ZHANG Danhua HU Yuanman +2 位作者 LIU Miao CHANG Yu SUN Lishuang 《Chinese Geographical Science》 SCIE CSCD 2020年第1期127-141,共15页
Biological invasion poses a huge threat to ecological security.Spartina alterniflora was introduced into China in 1979,and its arrival corresponded with negative effects on native ecosystems.To explore geographical va... Biological invasion poses a huge threat to ecological security.Spartina alterniflora was introduced into China in 1979,and its arrival corresponded with negative effects on native ecosystems.To explore geographical variation of its expansion rate in coastal China,we selected 43 S.alterniflora sites from Tianjin Coastal New Area to Beihai.The area expansion rate,expansion rate paralleling and vertical to the shoreline were analysed based on Landsat images and field survey in 2015.Simple Ocean Data Assimilation(SODA)and climate data were collected to statistically analyse the influential factors of expansion rate.Results showed that significant difference of S.alterniflora area expansion rate among different latitude zones(P<0.01),increasing from 6.08%at southern(21°N–23°N)to 19.87% in Bohai Bay(37°N–39°N)along latitude gradient.There was a significant difference in expansion rate vertical to shoreline in different latitude zones(P<0.01)with the largest occurring in Bohai Bay(256m/yr,37°N–39°N),and showed an decreasing tendency gradually from north to south.No significant difference and latitudinal clines in expansion rate paralleling to shoreline were observed.Expansion rate had significant negative correlation with mean seawater temperature,the lowest seawater temperature,current zonal velocity and meridional velocity and presented a reducing trend as these biotic factors increased;however,they were not significantly correlated with the highest seawater temperature and mean seawater salinity.We identified significant correlations between expansion rate and annual mean temperature,the lowest temperature in January and annual precipitation,but there was little correlation with annual diurnal difference in temperature and the highest temperature in July.The rapid expansion rate in high-latitude China demonstrated a higher risk of potential invasion in the north;dynamic monitoring and control management should be established as soon as possible. 展开更多
关键词 geographical variation biological invasion Spartina alterniflora expansion rate coastal wetlands China
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Geographical Information System-Based Assessment of Ecological Security in Changbai Mountain Region 被引量:7
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作者 LU Xing-chang ZHANG Ji-quan LI Xiao-zhen 《Journal of Mountain Science》 SCIE CSCD 2014年第1期86-97,共12页
Ecological security defined as the creation of a condition where the physical surroundings of a community provide for the needs of its inhabitants without diminishing its natural stock,which is important for regional ... Ecological security defined as the creation of a condition where the physical surroundings of a community provide for the needs of its inhabitants without diminishing its natural stock,which is important for regional security and social stability.In recent years,land use patterns in the Changbai Mountain region have changed significantly with intensive human activities,and consequently led to increasing problems in regional ecological security.Based on the Pressure-State-Impact-Response(PSIR) model and the mathematical method of catastrophe progression supported by geographical information system(GIS),the ecological security situation of the study area under land use and cover change(LUCC) was evaluated.The results indicated that the ecological security in Changbai Mountain region varied nonlinearly,which got better from 1990 to 2000 but became worse from 2000 to 2007,the ecological security levels in Changbai Mountain region were mainly medium and medium to low during the past 17 years,with higher values of Ecological Security Index(ESI) in the central region and lower values in the east and west,the ecological security situation was more serious in the settlements and river valleys,where the LUCC was most remarkable. 展开更多
关键词 ECOLOGICAL security Pressure-State-Impact-Response Land use and COVER change geographical Information System(GIS) CATASTROPHE PROGRESSION Changbai MOUNTAIN
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Genetic Differentiation of Different Geographical Populations of Bemisia tabaci (Gennadius) Complex 被引量:6
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作者 CHU Dong LIU Guo-xia +2 位作者 FAN Zhong-xue TAO Yun-li ZHANG You-jun 《Agricultural Sciences in China》 CAS CSCD 2007年第6期696-705,共10页
Bemisia tabaci (Gennadius) is a species complex, which includes different geographical populations with genetic differentiation. The recent progress on the genetic differentiation of various geographical populations... Bemisia tabaci (Gennadius) is a species complex, which includes different geographical populations with genetic differentiation. The recent progress on the genetic differentiation of various geographical populations of B. tabaci complex was introduced. The genetic differentiation was further analyzed on the basis of the sequences of mtDNA COI and rDNA ITS1 recorded in the world's GenBank. Five groups are defined on the basis of mtDNA COI and rDNA ITS1, including the Asia group, America group, Africa group, Australia group, and Biotype B/Mediterranean/Middle East/ Northern Africa/Biotype Ms group. There are several ungrouped geographical classifications, such as the Uganda population, Ivory Coast population, and Taiwan population. Geographical isolation may be the most important factor that contributed to the genetic differentiation of various geographical populations of B. tabaci. Many populations with biological advantages invaded new regions and caused severe economic losses within human activity. It is necessary to strengthen the research of B. tabaci biotype to prevent the spread of invaded populations and the invasion of potentially dangerous populations. 展开更多
关键词 Bemisia tabaci (Gennadius) geographical populations mtDNA COI rDNA ITS 1 genetic differentiation
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PHYSICAL STRUCTURE OF GEOGRAPHICAL ENVIRONMENT-INTEGRITY AND DISPARITY,GENERALITY AND INDIVIDUALITY 被引量:2
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作者 李春芬 《Chinese Geographical Science》 SCIE CSCD 1993年第4期3-10,共8页
Integrity and disparity are two of the basic characteristics implied in the scientific connotation of the physical environment as a material system. From a dialectical materialistic point of view the physical characte... Integrity and disparity are two of the basic characteristics implied in the scientific connotation of the physical environment as a material system. From a dialectical materialistic point of view the physical character of geographical environment of the earth surface is the unity in diversity. It is on such grounds that the two basic characteristics were put forth by the author in his monograph 'Physical Structure of South American Geographical Environment' as the underlying theme. This holds true for the hierarchy of physical regions. For instance, the physical environment of the earth surface in unity behaves as a huge whole, yet, in differentiation into continents, it displays disparity; each continent differs from others and becomes an integrity in its own right. The same is true of regions of lower levels. In the case of generality and individuality of regional types and their constituent distributive areas in different continents, the same relationship exists among them. Owing to similar origin 展开更多
关键词 PHYSICAL structure of geographical environment INTEGRITY DISPARITY GENERALITY INDIVIDUALITY
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