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Change in current and future geographic distributions of Ulmus lamellosa in China 被引量:2
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作者 Dongting Yan Wei Chen +3 位作者 Li Liu Jing Li Lin Liu Yiling Wang 《Journal of Forestry Research》 SCIE CAS CSCD 2018年第4期1134-1143,共10页
Prediction of potential geographic distributions is important for species protection and habitat restoration. Ulmus lamellosa is an endangered and endemic species in China for which conservation efforts are required. ... Prediction of potential geographic distributions is important for species protection and habitat restoration. Ulmus lamellosa is an endangered and endemic species in China for which conservation efforts are required. The maximum entropy (MaxEnt) model was used to predict the current and future geographic distribution (from 2030 to 2070) of U. lamellosa in China and discuss the reasons for changes in climatic suitability. The MaxEnt model provided a good fit to our data as confirmed by an AUC value of 0.948. The suitable areas for U. lamellosa were primarily projected in the northern part of China from 2030 to 2070, especially in Liaoning province. The variables "temperature seasonality", "precipitation of wettest month" and "precipitation of warmest quarter" were the most influential climatic variables in limiting the distribution of U. lamellosa. Our results clearly predict the future impacts of climate change on the geographic distribution of U. lamellosa and this can help prioritize design of localized conservation strategies in China. 展开更多
关键词 Ulmus lamellosa MAXENT GIS geographic distribution Suitable region
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Natural variations and geographical distributions of seed carotenoids and chlorophylls in 1167 Chinese soybean accessions 被引量:1
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作者 Berhane S.GEBREGZIABHER ZHANG Sheng-rui +7 位作者 Muhammad AZAM QI Jie Kwadwo G.AGYENIM-BOATENG FENG Yue LIU Yi-tian LI Jing LI Bin SUN Jun-ming 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2023年第9期2632-2647,共16页
Understanding the composition and contents of carotenoids in various soybean seed accessions is important for their nutritional assessment.This study investigated the variability in the concentrations of carotenoids a... Understanding the composition and contents of carotenoids in various soybean seed accessions is important for their nutritional assessment.This study investigated the variability in the concentrations of carotenoids and chlorophylls and revealed their associations with other nutritional quality traits in a genetically diverse set of Chinese soybean accessions comprised of cultivars and landraces.Genotype,planting year,accession type,seed cotyledon color,and ecoregion of origin significantly influenced the accumulation of carotenoids and chlorophylls.The mean total carotenoid content was in the range of 8.15–14.72μg g–1 across the ecoregions.The total carotenoid content was 1.2-fold higher in the landraces than in the cultivars.Soybeans with green cotyledons had higher contents of carotenoids and chlorophylls than those with yellow cotyledons.Remarkably,lutein was the most abundant carotenoid in all the germplasms,ranging from 1.35–37.44μg g–1.Carotenoids and chlorophylls showed significant correlations with other quality traits,which will help to set breeding strategies for enhancing soybean carotenoids without affecting the other components.Collectively,our results demonstrate that carotenoids are adequately accumulated in soybean seeds,however,they are strongly influenced by genetic factors,accession type,and germplasm origin.We identified novel germplasms with the highest total carotenoid contents across the various ecoregions of China that could serve as the genetic materials for soybean carotenoid breeding programs,and thereby as the raw materials for food sectors,pharmaceuticals,and the cosmetic industry. 展开更多
关键词 accession type carotenoid CHLOROPHYLL ECOREGION geographical distribution Pearson’s correlation soybean(Glycine max L.Merrill)
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Integrating Neighborhood Geographic Distribution and Social Structure Influence for Social Media User Geolocation
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作者 Meng Zhang Xiangyang Luo Ningbo Huang 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第9期2513-2532,共20页
Geolocating social media users aims to discover the real geographical locations of users from their publicly available data,which can support online location-based applications such as disaster alerts and local conten... Geolocating social media users aims to discover the real geographical locations of users from their publicly available data,which can support online location-based applications such as disaster alerts and local content recommen-dations.Social relationship-based methods represent a classical approach for geolocating social media.However,geographically proximate relationships are sparse and challenging to discern within social networks,thereby affecting the accuracy of user geolocation.To address this challenge,we propose user geolocation methods that integrate neighborhood geographical distribution and social structure influence(NGSI)to improve geolocation accuracy.Firstly,we propose a method for evaluating the homophily of locations based on the k-order neighbor-hood geographic distribution(k-NGD)similarity among users.There are notable differences in the distribution of k-NGD similarity between location-proximate and non-location-proximate users.Exploiting this distinction,we filter out non-location-proximate social relationships to enhance location homophily in the social network.To better utilize the location-proximate relationships in social networks,we propose a graph neural network algorithm based on the social structure influence.The algorithm enables us to perform a weighted aggregation of the information of users’multi-hop neighborhood,thereby mitigating the over-smoothing problem of user features and improving user geolocation performance.Experimental results on real social media dataset demonstrate that the neighborhood geographical distribution similarity metric can effectively filter out non-location-proximate social relationships.Moreover,compared with 7 existing social relationship-based user positioning methods,our proposed method can achieve multi-granularity user geolocation and improve the accuracy by 4.84%to 13.28%. 展开更多
关键词 User geolocation social media neighborhood geographic distribution structure influence
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Estimation of the potential geographical distribution of a new potato pest(Schrankia costaestrigalis) in China under climate change 被引量:3
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作者 XIAN Xiao-qing ZHAO Hao-xiang +4 位作者 GUO Jian-yang ZHANG Gui-fen LIU Hui LIU Wan-xue WAN Fang-hao 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2023年第8期2441-2455,共15页
Global food security is threatened by the impacts of the spread of crop pests and changes in the complex interactions between crops and pests under climate change.Schrankia costaestrigalis is a newly-reported potato p... Global food security is threatened by the impacts of the spread of crop pests and changes in the complex interactions between crops and pests under climate change.Schrankia costaestrigalis is a newly-reported potato pest in southern China.Early-warning monitoring of this insect pest could protect domestic agriculture as it has already caused regional yield reduction and/or quality decline in potato production.Our research aimed to confirm the potential geographical distributions(PGDs)of S.costaestrigalis in China under different climate scenarios using an optimal MaxEnt model,and to provide baseline data for preventing agricultural damage by S.costaestrigalis.Our findings indicated that the accuracy of the optimal MaxEnt model was better than the default-setting model,and the minimum temperature of the coldest month,precipitation of the driest month,precipitation of the coldest quarter,and the human influence index were the variables significantly affecting the PGDs of S.costaestrigalis.The highly-and moderately-suitable habitats of S.costaestrigalis were mainly located in eastern and southern China.The PGDs of S.costaestrigalis in China will decrease under climate change.The conversion of the highly-to moderately-suitable habitat will also be significant under climate change.The centroid of the suitable habitat area of S.costaestrigalis under the current climate showed a general tendency to move northeast and to the middle-high latitudes in the 2030s.The agricultural practice of plastic film mulching in potato fields will provide a favorable microclimate for S.costaestrigalis in the suitable areas.More attention should be paid to the early warning and monitoring of S.costaestrigalis in order to prevent its further spread in the main areas in China’s winter potato planting regions. 展开更多
关键词 climate change potential geographical distribution crop insect pests Schrankia costaestrigalis MaxEnt model
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Monitoring the little fire ant,Wasmannia auropunctata(Roger 1863),in the early stage of its invasion in China:Predicting its geographical distribution pattern under climate change 被引量:1
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作者 ZHAO Hao-xiang XIAN Xiao-qing +5 位作者 GUO Jian-yang YANG Nian-wan ZHANG Yan-ping CHEN Bao-xiong HUANG Hong-kun LIU Wan-xue 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2023年第9期2783-2795,共13页
Invasive alien ants(IAAs)are among the most aggressive,competitive,and widespread invasive alien species(IAS)worldwide.Wasmannia auropunctata,the greatest IAAs threat in the Pacific region and listed in“100 of the wo... Invasive alien ants(IAAs)are among the most aggressive,competitive,and widespread invasive alien species(IAS)worldwide.Wasmannia auropunctata,the greatest IAAs threat in the Pacific region and listed in“100 of the world’s worst IAS”,has established itself in many countries and on islands worldwide.Wild populations of W.auropunctata were recently reported in southeastern China,representing a tremendous potential threat to China’s agricultural,economic,environmental,public health,and social well-being.Estimating the potential geographical distribution(PGD)of W.auropunctata in China can illustrate areas that may potentially face invasion risk.Therefore,based on the global distribution records of W.auropunctata and bioclimatic variables,we predicted the geographical distribution pattern of W.auropunctata in China under the effects of climate change using an ensemble model(EM).Our findings showed that artificial neural network(ANN),flexible discriminant analysis(FDA),gradient boosting model(GBM),Random Forest(RF)were more accurate than categorical regression tree analysis(CTA),generalized linear model(GLM),maximum entropy model(MaxEnt)and surface distance envelope(SRE).The mean TSS values of ANN,FDA,GBM,and RF were 0.820,0.810,0.843,and 0.857,respectively,and the mean AUC values were 0.946,0.954,0.968,and 0.979,respectively.The mean TSS and AUC values of EM were 0.882 and 0.972,respectively,indicating that the prediction results with EM were more reliable than those with the single model.The PGD of W.auropunctata in China is mainly located in southern China under current and future climate change.Under climate change,the PGD of W.auropunctata in China will expand to higher-latitude areas.The annual temperature range(bio7)and mean temperature of the warmest quarter(bio10)were the most significant variables affecting the PGD of W.auropunctata in China.The PGD of W.auropunctata in China was mainly attributed to temperature variables,such as the annual temperature range(bio7)and the mean temperature of the warmest quarter(bio10).The populations of W.auropunctata in southern China have broad potential invasion areas.Developing strategies for the early warning,monitoring,prevention,and control of W.auropunctata in southern China requires more attention. 展开更多
关键词 invasive alien ants potential geographical distribution Wasmannia auropunctata climate change Ensemble model
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Geographical distribution of Batrachospermaceae genera in Asia and its environmental factors
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作者 Mingyu QIU Fei WANG +5 位作者 Fangru NAN Jia FENG Junping LÜ Qi LIU Xudong LIU Shulian XIE 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2023年第3期972-990,共19页
Batrachospermaceae is an important group of freshwater red algae.Available data of the latitude,longitude,and environmental factors on Batrachospermaceae distribution in Asia were analyzed to understand the geographic... Batrachospermaceae is an important group of freshwater red algae.Available data of the latitude,longitude,and environmental factors on Batrachospermaceae distribution in Asia were analyzed to understand the geographical distribution of Batrachospermaceae genera in Asia.Statistical analyses,including one-way ANOVA,correlation analysis,stepwise regression analysis,principal component analysis,and linear discriminant analysis were conducted to characterize variation in geographical distribution and growth environment.Results reveal high variation in geographical distribution and growth environment among different Batrachospermaceae genera in Asia.Specifically,correlations between latitude and all environmental factors exclusive of altitude are significant,and longitude is significantly correlated with all environmental factors except for average relative humidity.The geographical distribution and growth environment of different Batrachospermaceae genera significantly differed.Altitude,maximum temperature,average temperature,minimum temperature,average relative humidity,average wind speed,maximum wind speed,and atmospheric pressure all contributed to explaining differences in the geographical distribution of Batrachospermaceae genera.Combining the results of correlation analysis,stepwise regression analysis,and principal component analysis,all environmental factors contributed to the different geographical distribution of Batrachospermum,Paludicola,Sheathia,Sirodotia,and Remainder(the rest),all environmental factors but atmospheric pressure contributed to the different geographical distribution of Kumanoa,and all environmental factors but average wind speed and maximum wind speed contributed to the different geographical distribution of Virescentia.However,the correlation between these significantly related environmental factors and taxa is not necessarily causative,and many other environmental factors,such as temperature,pH,conductivity,shading,current velocity,dissolved oxygen,hardness,substrata types,and nutrients etc.,are likely to have an important impact on the geographical distribution of taxa,which is an important topic for future research. 展开更多
关键词 Batrachospermaceae BIOSTATISTICS environmental factor geographical distribution METROLOGY
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Predicting the potential geographic distribution of Bactrocera bryoniae and Bactrocera neohumeralis(Diptera: Tephritidae) in China using MaxEnt ecological niche modeling 被引量:7
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作者 Jing Wan QI Guo-jun +3 位作者 MA Jun Yonglin REN WANG Rui Simon MCKIRDY 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2020年第8期2072-2082,共11页
Bactrocera bryoniae and Bactrocera neohumeralis are highly destructive and major biosecurity/quarantine pests of fruit and vegetable in the tropical and subtropical regions in the South Pacific and Australia.Although ... Bactrocera bryoniae and Bactrocera neohumeralis are highly destructive and major biosecurity/quarantine pests of fruit and vegetable in the tropical and subtropical regions in the South Pacific and Australia.Although these pests have not established in China,precautions must be taken due to their highly destructive nature.Thus,we predicted the potential geographic distribution of B.bryoniae and B.neohumeralis across the world and in particular China by ecological niche modeling of the Maximum Entropy(Max Ent)model with the occurrence records of these two species.Bactrocera bryoniae and B.neohumeralis exhibit similar potential geographic distribution ranges across the world and in China,and each species was predicted to be able to distribute to over 20%of the globe.Globally,the potential geographic distribution ranges for these two fruit fly species included southern Asia,the central and the southeast coast of Africa,southern North America,northern and central South America,and Australia.While within China,most of the southern Yangtze River area was found suitable for these species.Notably,southern China was considered to have the highest risk of B.bryoniae and B.neohumeralis invasions.Our study identifies the regions at high risk for potential establishment of B.bryoniae and B.neohumeralis in the world and in particular China,and informs the development of inspection and biosecurity/quarantine measures to prevent and control their invasions. 展开更多
关键词 fruit fly Bactrocera bryoniae Bactrocera neohumeralis ecological niche modeling MAXENT potential geographic distribution habitat suitability
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Geographic Distribution of Mating Types in Magnaporthe grisea and the Relationship Between Fertile Isolates in China 被引量:5
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作者 SHEN Ying, Notteghem Jean Loup., Milazzo Joelle., YUAN Xiao-ping, Adreit Henry, ZHAO Xin-hua, WANG Yan-li and Tharreau Didier.(China National Rice Research Institute, Hangzhou 310006, P. R. China National Institute of Agronomic Research ,Unit of Training and Biological Research , Ecology and Plant Pathology, 2 Place Viala , 34062 Montpellier , France International Center for collaboration in Agronomic Research and Development,TA 73 /09 , 34398 Montpellier , Cedex 05 , France) 《Agricultural Sciences in China》 CAS CSCD 2002年第6期648-656,共9页
377 isolates of Magnaporthe grisea were collected from 17 provinces in China and their geographic distribution of mating types and their fertility was tested with four standard isolates, KA3 and TH12 (Mat1.1) and Guy1... 377 isolates of Magnaporthe grisea were collected from 17 provinces in China and their geographic distribution of mating types and their fertility was tested with four standard isolates, KA3 and TH12 (Mat1.1) and Guy11 and TH16 (Mat1.2) provided by CIRAD. 73 fertile isolates were tested with SCAR markers of 13 pairs of primers. Preliminary results showed that the geographic distribution of M.grisea existed among isolates collected from the same location as well as different locations and the genetic relationship between fertile isolates of the fungus in China. The existence of sexual reproduction of M .grisea was explored in the field as well. 展开更多
关键词 Magnaporthe grisea Fertile isolates geographic Distribution SCARS Genetic relationship
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Geographical Patterns of Chinese Ethnic Minority Population Composition and Ethnic Diversity 被引量:3
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作者 SHEN Zehao LI Peng +1 位作者 SUN Hongkai PANG Lihua 《Chinese Geographical Science》 SCIE CSCD 2011年第4期454-464,共11页
Ethnicity is a carrier of language and culture.Spatial distribution of ethnic diversity is fundamental for identifying and reconstructing the migration patterns and evolution histories of cultures and languages.Utiliz... Ethnicity is a carrier of language and culture.Spatial distribution of ethnic diversity is fundamental for identifying and reconstructing the migration patterns and evolution histories of cultures and languages.Utilizing the Chinese 4th National Census (1990) data,we investigated the specific time geographical patterns of population and diversity of Chinese ethnicminorities.As anticipated,results show that Chineseminorities are chiefly concentrated in dis-tant plateaus and mountains in the southwest,northwest and northeast of China.Further,population density centers of the 10 majorminorities are rather scattered,alternatively dominating at different parts of the country.This study pro-vides a first comprehensive quantitative test on a prevailing notion of 'six plates and three corridors' on the empirical clustering patterns of Chinese ethnicminorities.There are more consistent evidences supporting this notion in the north of China,with the central and southern regions showing more complex patterns,potentially transformed by processes such as migration,fragmentation,and percolation.The results of this study suggest that a geographical ap-proach can provide heuristic and complementary information for better understanding of historical social processes. 展开更多
关键词 ethnicminority ethnic diversity geographical distribution CLASSIFICATION
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Hospital-Based Phenotypic Features and Treatment Outcomes of Chinese Women with Polycystic Ovary Syndrome: The Effect of Body Mass Index and Geographic Distribution 被引量:3
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作者 Jingshu Gao Hongli Ma +5 位作者 Yu Wang Xinming Yang Yijuan Cao Bei Zhang Conghui Han Xiaoke Wua 《Engineering》 SCIE EI 2021年第2期170-177,共8页
Genetic,lifestyle,and environmental factors contribute to the etiology of polycystic ovary syndrome(PCOS).Increased body mass index(BMI)exacerbates the reproductive and metabolic parameters and reduces the fecundity o... Genetic,lifestyle,and environmental factors contribute to the etiology of polycystic ovary syndrome(PCOS).Increased body mass index(BMI)exacerbates the reproductive and metabolic parameters and reduces the fecundity of women with PCOS.This is a secondary analysis of a large-sample,multicenter,randomized controlled trial conducted at 21 sites in Chinese mainland.A total of 1000 women diagnosed with PCOS were enrolled in this trial.Of these,998 women with PCOS were included in the analysis.Increased BMI was associated with more severe menstrual irregularities,elevated testosterone level,higher prevalence of metabolic syndrome,and poorer quality of life.The rates of ovulation per woman for the normal,overweight,and obese BMI groups were 83.0%,78.2%,and 63.6%,respectively(P<0.001),and the rates of live birth were 23.6%,18.1%,and 15.3%(P=0.030).Northern PCOS patients showed more severe reproductive,glucose,and lipid profiles;less exercise;and lower total ovulation rates compared with PCOS patients from Southern China(74.8%vs 81.2%,absolute difference 6.4%,95%confidence interval 1.2%–11.5%).The results show the typical phenotypic features of Han women with PCOS in Northern and Southern China.The women living in Northern China showed a higher BMI,more severe glycolipid metabolism profiles,and subsequently worse clinical outcomes by the same interventions than those living in Southern China.The difference in phenotypic features can be explained mostly by differences in BMI and the resulting difference in ovulation. 展开更多
关键词 Polycystic ovary syndrome Body mass index PHENOTYPE Chinese cohort geographic distribution
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Life form and geographical distribution of plants in Posthband region,Khonj,Fars Province,Iran 被引量:2
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作者 Gholamhosein Moradi Mohammad Reza Marvie Mohadjer +2 位作者 Ghavamodin Zahedi Amiri Anoushirvan Shirvany Nosratollah Zargham 《Journal of Forestry Research》 SCIE CAS CSCD 2010年第2期201-206,I0006,共7页
A study was conducted to identify plant species,diversity,life form and relevant species to Mediterranean climate,Irano-Torunian and Sahara-Sindian in Postband region(N 27°58'4"-28°2'16",E 53°17'3... A study was conducted to identify plant species,diversity,life form and relevant species to Mediterranean climate,Irano-Torunian and Sahara-Sindian in Postband region(N 27°58'4"-28°2'16",E 53°17'34"-53°22'30").In total,95 species belonging to 29 families and 69 genera of flora were surveyed and identified from December 2006 to June 2008.Composite and Gramineae were important families in terms of species frequency.According to Raunkiaer's system and using X^2 tests,the life-form spectrum showed that therophytes accounted for 47% of all species,and hemicryptophytes for 31%,phanerophytes for 12%,chamaeophyte for 7%,and cryptophytes for 3%.In geographical distribution,29% species with the most frequency belonged to Irano-Torunian region.Results show that therophytes were more than normal spectrum and phaneropytes were less than normal spectrum,which was in agreement with data obtained in arid climate. 展开更多
关键词 geographical distribution life form Khalije-omani forest FLORA Posthband
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Architecture of HLA Based Distributed Virtual Geographic Environment 被引量:2
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作者 XU Bingli LIN Hui GONG Jianhua 《Geo-Spatial Information Science》 2006年第2期127-134,共8页
Integrating the theory of distributed virtual geographic environment (DVGE) and high level architecture(HLA), the architecture of DVGE based on HLA is designed. The data flow and the object models of the architecture ... Integrating the theory of distributed virtual geographic environment (DVGE) and high level architecture(HLA), the architecture of DVGE based on HLA is designed. The data flow and the object models of the architecture are also discussed. The architecture basically meets the need of DVGE in real-time communication, distribution, collaboration, reusing and interoperation, expansion, and standard. 展开更多
关键词 distributed virtual geographic environment high level architecture runtime infrastructure ARCHITECTURE
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IMMIGRATION, GEOGRAPHIC DISTRIBUTION AND SOCIAL ECONOMIC STATUS OF AMERICAN CHINESE 被引量:1
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作者 Zhang Zhenyu Henan Institute of Geography, Zhengzhou 450052, P.R.ChinaWang Jue The University of Kansas, Lawrence, USA 《Journal of Geographical Sciences》 SCIE CSCD 1997年第1期93-98,共6页
In 1994, the total Chinese population in the United States were 2,017,799 which were 0.8 percent of the total US population. The Chinese population were highly concentrated by regions and among the total population. B... In 1994, the total Chinese population in the United States were 2,017,799 which were 0.8 percent of the total US population. The Chinese population were highly concentrated by regions and among the total population. By states, 42 percent of total Chinese population were found in California, 17 percent in New York. More than 80 percent total Chinese population were concentrated in 9 states. By metropolitan areas, 14.73 percent of total Chinese population were found in Los Angeles and New York respectively. Compared with the total US population, 60 percent Chinese population were found in less than 20 percent total US population and 80 percent in 50 percent. By studying the Chinese population distribution and the reason behind it, we hope to find some interesting relationships among the characteristics of this distribution and the historical, cultural, social and economic factors influencing it. 展开更多
关键词 American Chinese IMMIGRATION geographic distribution social economic status.
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Preliminary Study on Geographical Distribution and Evolutionary Relationships Between Cultivated and Wild Adzuki Bean (Vigna angular is var. angularis and var. nipponensis) by AFLP Analysis 被引量:1
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作者 ZONGXu-xiao DuncanVaughan +4 位作者 NorihikoTomooka AkitoKaga WANGXin-wang GUANJian-ping WANGShu-min 《Agricultural Sciences in China》 CAS CSCD 2003年第4期368-376,共9页
A set of representative 146 adzuki (Vigna angular is var. angularis, and var. nipponensis) germplasm from 6 Asian countries traditionally for adzuki bean production, together with an out group standard rice bean (Vign... A set of representative 146 adzuki (Vigna angular is var. angularis, and var. nipponensis) germplasm from 6 Asian countries traditionally for adzuki bean production, together with an out group standard rice bean (Vigna umbellata), were analyzed by AFLP methodology using 12 informative primer pairs. 313 unambiguous polymorphic bands were created. According to the dendrogram by cluster analysis based on AFLP banding, 143 of the accessions were distinct and revealed enough genetic diversity for identification and classification of accessions within Vigna angularis. A neighbor joining tree was generated using newly developed Innan's nucleotide diversity estimate from the AFLP data. From analysis, 7 distinct evolutionary groups, named as "Chinese cultivated", "Japanese cultivated", "Japanese complex-Korean cultivated", "Chinese wild", "China Taiwan wild", "Nepal-Bhutan cultivated" and "Hymalayan wild", were detected. Nucleotide diversity with geographical distribution of each group is discussed, regarding the evolutionary relationships between wild and cultivated adzuki beans. The preliminary results indicated that cultivated adzuki bean should be domesticated from at least 4 progenitors in at least 3 geographical origins. 展开更多
关键词 Adzuki bean (Vigna angularis) AFLP Genetic diversity geographical distribution Evolutionary relationships
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C_4 plant species and geographical distribution in relation to climate in the desert vegetation of China 被引量:1
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作者 PeiXi Su TingTing Xie ZiJuan Zhou 《Research in Cold and Arid Regions》 2011年第5期381-391,共11页
Water use efficiency of Ca plants is higher than that of C3 plants, and CAM (Crassulaceae Acid Metabolism) plants have the highest water use efficiency. In the desert regions of China, CAM plants are scarce, and C4 ... Water use efficiency of Ca plants is higher than that of C3 plants, and CAM (Crassulaceae Acid Metabolism) plants have the highest water use efficiency. In the desert regions of China, CAM plants are scarce, and C4 plants, especiaUy C4 woody plants, have an important position and role in the desert ecosystem. There are 45 species of Ca woody plants in the desert regions of China, including semi-woody plants, accounting for 6% of the total desert plant species in China, and most of them are concentrated in the families of Chenopodiaceae and Polygonaceae, which are 19 species and 26 species, respectively. The number of C4 herbaceous plants is 107 species, including 48 monocot species and 59 dicot species. C4 woody plants mainly inhabit the northwestem arid desert regions of China west of the Helan Mountains. The drought-resistance and drought-tolerance of Ca herbaceous plants are worse than C4 woody plants, and C4 herbaceous plants mainly inhabit areas with shallow groundwater depth and better water conditions in the desert regions, and are widely distributed along the margins of oases. The abundance of C4 woody plants is closely correlated with drought, but the abundance of C4 herbaceous plants increases with wet conditions. 展开更多
关键词 desert plant Ca photosynthesis woody plant geographical distribution
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Spatial distribution of snow depth based on geographically weighted regression kriging in the Bayanbulak Basin of the Tianshan Mountains, China 被引量:5
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作者 LIU Yang LI Lan-hai +2 位作者 CHEN Xi YANG Jin-Ming HAO Jian-Sheng 《Journal of Mountain Science》 SCIE CSCD 2018年第1期33-45,共13页
Snow depth is a general input variable in many models of agriculture,hydrology,climate and ecology.This study makes use of observational data of snow depth and explanatory variables to compare the accuracy and effect ... Snow depth is a general input variable in many models of agriculture,hydrology,climate and ecology.This study makes use of observational data of snow depth and explanatory variables to compare the accuracy and effect of geographically weighted regression kriging(GWRK)and regression kriging(RK)in a spatial interpolation of regional snow depth.The auxiliary variables are analyzed using correlation coefficients and the variance inflation factor(VIF).Three variables,Height,topographic ruggedness index(TRI),and land surface temperature(LST),are used as explanatory variables to establish a regression model for snow depth.The estimated spatial distribution of snow depth in the Bayanbulak Basin of the Tianshan Mountains in China with a spatial resolution of 1 km is obtained.The results indicate that 1)the result of GWRK's accuracy is slightly higher than that of RK(R^2=0.55 vs.R^2=0.50,RMSE(root mean square error)=0.102 m vs.RMSE=0.077 m);2)for the subareas,GWRK and RK exhibit similar estimation results of snow depth.Areas in the Bayanbulak Basin with a snow depth greater than 0.15m are mainly distributed in an elevation range of 2632.00–3269.00 m and the snow in this area comprises 45.00–46.00% of the total amount of snow in this basin.However,the GWRK resulted in more detailed information on snow depth distribution than the RK.The final conclusion is that GWRK is better suited for estimating regional snow depth distribution. 展开更多
关键词 Snow depth Spatial distribution Regression kriging geographically weighted regression kriging
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Geographical distribution of Aralia elata characteristics correlated with topography and forest structure in Heilongjiang and Jilin Provinces,Northeast China
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作者 Hongxu Wei Guoshuang Chen +1 位作者 Xin Chen Hengtian Zhao 《Journal of Forestry Research》 SCIE CAS CSCD 2021年第3期1115-1125,共11页
The Araliaceae family consists of numerous species of medical plants of significant value as non-wood forest products.To conserve and culture these plants in natural forest stands is an important undertaking which sho... The Araliaceae family consists of numerous species of medical plants of significant value as non-wood forest products.To conserve and culture these plants in natural forest stands is an important undertaking which should be implemented according to the relationship between forest structure and understory population.In this study,thirtyfive plots were established in natural A ralia elata stands.Taller individual and denser populations were found in the northern and in the eastern regions,respectively.Both population densities and individual leaf weight increased along longitude.In contrast,their relationship with elevation and DBH were negative.Along with the altitude gradient,both height and root-collar diameter increased but population density declined.Root-collar diameter and population density decreased with latitude and DBH,respectively.Overall,dominant trees unlikely enforced strong disturbance to the development of understory A.elata populations unless concerning some specific topographic factors. 展开更多
关键词 Aralia elata Chinese angelica-tree Stand quality geographical distribution Undergrowth Nontimber forest species
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Prediction of the global potential geographical distribution of Hylurgus ligniperda using a maximum entropy model
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作者 Zhuojin Wu Tai Gao +1 位作者 Youqing Luo Juan Shi 《Forest Ecosystems》 SCIE CSCD 2022年第4期449-459,共11页
Background: Hylurgus ligniperda(Fabricius) is native to Europe but has established populations in many countries and regions. H. ligniperda mainly infests Pinus species, and can cause severe weakness and even death of... Background: Hylurgus ligniperda(Fabricius) is native to Europe but has established populations in many countries and regions. H. ligniperda mainly infests Pinus species, and can cause severe weakness and even death of the host through its boring activity;it can also be a vector of various pathogenic fungi. This study was conducted to investigate the environmental variables limiting the distribution of H. ligniperda and the change trend of its suitable areas under climate change.Results: We used a maximum entropy model to predict the potential geographical distribution of H. ligniperda on a global scale under near current and future climatic scenarios using its occurrence data and environmental variables. The result shows that the areas surrounding the Mediterranean region, the eastern coastal areas of Asia, and the southeastern part of Oceania are highly suitable for H. ligniperda. The environmental variables with the greatest effect on the distribution of H. ligniperda were determined using the jackknife method and Pearson’s correlation analysis and included the monthly average maximum temperature in April, precipitation of driest quarter, the monthly average minimum temperature in December, precipitation of coldest quarter, mean temperature of driest quarter and mean diurnal range.Conclusions: Excessive precipitation in winter and low temperatures in spring had a great effect on the distribution of H. ligniperda. The potential geographical distribution of H. ligniperda was predicted to change under future climatic conditions compared with near current climate conditions. Highly suitable areas, moderately suitable areas and low suitable areas were predicted to increase by 59.99%, 44.43% and 22.92%, respectively, under the2081–2100 ssp245 scenario. 展开更多
关键词 Climate change Hylurgus ligniperda Invasive pest Maximum entropy model Potential geographical distribution
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The change of geographical distribution of two Asian species of rhinoceros in Holocene
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作者 Liu Hongjie Department of Geography, South China Normal University, Guangzhou 510631, CHINA 《Journal of Geographical Sciences》 SCIE CSCD 1998年第1期84-89,共6页
At present only five species of rhinoceros surrive in the world, among which three in Asia No wild rhinoceros has been found alive in East Asia now But many recent evidences reveal the fact that rhinoceros still liv... At present only five species of rhinoceros surrive in the world, among which three in Asia No wild rhinoceros has been found alive in East Asia now But many recent evidences reveal the fact that rhinoceros still lived not very long ago in the East Asian Continent of Holocene The attention to East Asia rhinoceros in Holocene first arose from archaeological studies on ancient ruins in China Archaeologists first found some subfossil skeletons of rhinoceros in ruins of Yin Dynasty in Anyang of Henan in the 1930s Then more skeletons of rhinoceros were found in many other Neolithic Ages runis, such as in Tonghai (Yunnan), Nanning (Guangxi), Xichuan (Henan), Yuyao (Zhejiang), and Haian (Jiangsu).(Guangxi Archaeological Team 1972; Jia 1977; Wu 1983; Huang and Liang 1984; Xu 1990). Moreover, Zhou Benxiong reported some rhinoceros teeth containing residual organic matter found in caves in the middle and lower reaches of Yangtze River According to a number of very now skeletons of rhinoceros found in some caves in Central China and South China, Yang Zhongjian drew the inferences that rhinoceros might live in the Southern part of China until in the Han Dynasty (about 2000 yrs B P ) at least These discoveries provided the material evidences for the distribution of rhinoceros in East Asian Continent Recently, some scholars brought forward more new information about Chinese rhinoceros from the analysis of historical records and investigations of unearthed cultural relics respectively (Wen and He 1981; Sun 1982). Based on the above materials and informations, this paper is going to deal with the species of rhinoceros once living in East Asia from the viewpoint of zoo geography At last, we brouhgt up the evolution process of the rhinoceros in distribution in Asia with comprehensive analysis of physiographical elements and human activities 展开更多
关键词 RHINOCEROS geographical distribution evolution process East Asia Holocence
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Characteristics of phosphorus chemistry and its geographical distribution in the Haihe River valley,North China
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作者 Jiang Gaoming Huang Yinxiao +2 位作者 Lin Shunhua Han Rongzhuang Gao Leiming (Institute of Botany,Chinese Academy of Sciences, Beijing 100044,China) 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 1995年第1期12-23,共12页
CharacteristicsofphosphoruschemistryanditsgeographicaldistributionintheHaiheRivervalley,NorthChinaJiangGaomi... CharacteristicsofphosphoruschemistryanditsgeographicaldistributionintheHaiheRivervalley,NorthChinaJiangGaoming;HuangYinxiao;L... 展开更多
关键词 phosphorus contents in plants geographical distribution Haihe River valley.
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