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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:2
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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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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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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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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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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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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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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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The Geographical Distribution and Historical Strata of Appellation Words Referring to "FATHER" in Jin Dialects --Exploring the Causes for the Formation of Historical Strata of Dialect Words
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作者 BAI Yun 《Sino-US English Teaching》 2016年第10期802-813,共12页
Based on geographical distribution and literature survey, the present study constructs the historical strata of the appellation words referring to "FATHER" in Jin Dialects. It holds that the patterns of the appellat... Based on geographical distribution and literature survey, the present study constructs the historical strata of the appellation words referring to "FATHER" in Jin Dialects. It holds that the patterns of the appellation words are the result of superposition of different historical periods. But their leading words directly inherit the appellation words of standard language of the Song Dynasty and are mainly monosyllabic words. Words used before the Song Dynasty as living fossils of the words only retain in some districts or localities. The different evolution route of"pa (爸)" and "tiε (爹)" either in Jin dialects or in mandarin is a further proof that Jin dialects and mandarin evolves asynchronously. In addition, it maintains that the formulation of the historical strata is the interaction of the horizontal transmission of languages and systemic changes of local dialects. 展开更多
关键词 Jin dialects "FATHER" words geographical distribution ORIGIN horizontal transmission
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Geographical distribution of general aerobic heterotrophic bacteria in surficial sediments from the Chukchi Sea and Canadian Basin
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作者 高爱国 陈皓文 《Chinese Journal of Polar Science》 2007年第2期147-154,共8页
This paper determined the abundance of General Aerobic heterotrophic Bacteria (GAB) in surficial sediments from the Chukchi Sea and the Canadian basin by using MPN and discussed their geographical distribution. The ... This paper determined the abundance of General Aerobic heterotrophic Bacteria (GAB) in surficial sediments from the Chukchi Sea and the Canadian basin by using MPN and discussed their geographical distribution. The result shows that the determination percentages of the GAB were high, even till 100 percentage. The abundance range and averages of GAB for 4℃and 25℃ were from 4.00 × 10^2 to 2.40× 10^6 , 1.71×10^6 ind.·g^-1 (wet sample ) and from 2.40 ×10^5 to 2.40×10^7 , 1.10×10^7 ind. ·g^-1 (wet sample ) respectively. Not only the abundance range but also the averages of GAB in 25℃ were higher than that in 4℃. The abundance of GAB in sediments show a tendency that it is roughly greater in the lower latitudinal area than in the higher latitudinal area. The abundance of GAB increased from east to west as for the longitudinal distribution. With the water depth increasing, the abundance of GAB at 4℃ decreased, but GBA at 25℃ is not changed obviously with water depth. It seems that warmer circumstantial temperature is more suitable for some GAB. 展开更多
关键词 the Arctic Ocean the Chukchi Sea the Canadian Basin General Aerobic Heterotrophic Bacteria (GAB) geographic distribution.
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FKF1b controls reproductive transition associated with adaptation to geographical distribution in maize 被引量:1
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作者 Suhui Chen Shan Gao +6 位作者 Dongyang Wang Jie Liu Yingying Ren Zhihan Wang Xin Wei Qin Wang Xuehui Huang 《Journal of Integrative Plant Biology》 SCIE CAS CSCD 2024年第5期943-955,共13页
Maize(Zea mays subspecies mays)is an important commercial crop across the world,and its flowering time is closely related to grain yield,plant cycle and latitude adaptation.FKF1 is an essential clock-regulated blue-li... Maize(Zea mays subspecies mays)is an important commercial crop across the world,and its flowering time is closely related to grain yield,plant cycle and latitude adaptation.FKF1 is an essential clock-regulated blue-light receptor with distinct functions on flowering time in plants,and its function in maize remains unclear.In this study,we identified two FKF1 homologs in the maize genome,named ZmFKF1a and ZmFKF1b,and indicated that ZmFKF1a and ZmFKF1b independently regulate reproductive transition through interacting with ZmCONZ1 and ZmGI1 to increase the transcription levels of ZmCONZ1 and ZCN8.We demonstrated that ZmFKF1b underwent artificial selection during modern breeding in China probably due to its role in geographical adaptation.Furthermore,our data suggested that ZmFKF1bHap_C7 may be an elite allele,which increases the abundance of ZmCONZ1 mRNA more efficiently and adapt to a wider range of temperature zone than that of ZmFKF1bHap_Z58 to promote maize floral transition.It extends our understanding of the genetic diversity of maize flowering.This allele is expected to be introduced into tropical maize germplasm to enrich breeding resources and may improve the adaptability of maize at different climate zones,especially at temperate region. 展开更多
关键词 FLOWERING geographical distribution MAIZE ZmFKF1
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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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Genetic Diversity: Geographical Distribution and Toxin Profiles of Microcystis Strains (Cyanobacteria) in China 被引量:12
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作者 Zhong-Xing Wu Nan-Qin Gan Li-Rong Song 《Journal of Integrative Plant Biology》 SCIE CAS CSCD 2007年第3期262-269,共8页
Twenty strains of Microcystis Kütz were isolated from different freshwater bodies in China to analyze the diversity, geographical distribution and toxin profiles. Based on whole-cell polymerase chain reaction of ... Twenty strains of Microcystis Kütz were isolated from different freshwater bodies in China to analyze the diversity, geographical distribution and toxin profiles. Based on whole-cell polymerase chain reaction of cpcBA-IGS nucleotlde sequence, the derived neighbor-joining (NJ) and maximum parsimony (MP) trees Indicate that these strains of Microcystis can be divided into four clusters. The strains from south, middle and north region of China formed distinct lineages, suggesting high diversity and a geographical distribution from south to north locations. Moreover, the results being indicating high variable genotypes of the strains of the Microcystis strains from the same lake show that there Is high diversity of Microcystis within a water bloom population. Comparing the results of the present study with those reported for compared with 43 strains of Microcystis from other locations, also reveals Chinese strains have high similarity with those from regions in the North Hemispherical. This suggests that the Microcystis strains In the world might have a geographical distribution. Analysis of 30 strains using the primers MCF/TER and TOX2P/TOX2M showed that there was no correlation between the gene of cpcBA-IGS and the presence of racy. Toxic strains were founded to be predominant in different water bodies throughout China. 展开更多
关键词 diversity geographical distribution MICROCYSTIN MICROCYSTIS
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The Characterization and Geographical Distribution of the Genes Responsible for Vernalization Requirement in Chinese Bread Wheat 被引量:12
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作者 Qing-Ming Sun Rong-Hua Zhou +2 位作者 Li-Feng Gao Guang-Yao Zhao Ji-Zeng Jia 《Journal of Integrative Plant Biology》 SCIE CAS CSCD 2009年第4期423-432,共10页
The frequency and distribution of the major vernalization requirement genes and their effects on growth habits were studied. Of the 551 bread wheat genotypes tested, seven allelic combinations of the three Vrn-1 genes... The frequency and distribution of the major vernalization requirement genes and their effects on growth habits were studied. Of the 551 bread wheat genotypes tested, seven allelic combinations of the three Vrn-1 genes were found to be responsible for the spring habit, three for the facultative habit and one for the winter habit. The three Vrn-1 genes behaved additiveiy with the dominant allele of Vrn-A1 exerting the strongest effect. The allele combinations of the facultative genotypes and the discovery of spring genotypes with "winter" allele of Vrn-1 implied the presence of as yet unidentified alleles/genes for vernalization response. The dominant alleles of the three Vrn-1 genes were found in all ten ecological regions where wheat is cultivated in China, with Vrn-D1 as the most common allele in nine and Vrn-A1 in one. The combination of vrn-A1vrn-B1Vrn-D1 was the predominant genotype in seven of the regions. Compared with landraces, improved varieties contain a higher proportion of the spring type. This was attributed by a higher frequency of the dominant Vrn-A1 and Vrn-B1 alleles in the latter, Correlations between Vrn-1 allelic constitutions and heading date, spike length, plant type as well as cold tolerance were established. 展开更多
关键词 common wheat GENOTYPING geographical distribution vernalization.
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Phlebotomine sand flies(Diptera:Psychodidae)transmitting visceral leishmaniasis and their geographical distribution in China:a review 被引量:7
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作者 Li-Ren Guan Zheng-Bin Zhou +2 位作者 Chang-Fa Jin Qing Fu Jun-Jie Chai 《Infectious Diseases of Poverty》 SCIE 2016年第1期126-138,共13页
After the existence of phlebotomine sand flies was first reported in China in 1910,the distribution of different species and their role in the transmission of visceral leishmaniasis(VL)have been extensively studied.Up... After the existence of phlebotomine sand flies was first reported in China in 1910,the distribution of different species and their role in the transmission of visceral leishmaniasis(VL)have been extensively studied.Up until 2008,four species have been verified as vectors of VL,namely,Phlebotomus chinensis(Ph.sichuanensis),Ph.longiductus(Ph.chinensis longiductus),Ph.wui(Ph.major wui),and Ph.alexandri.The sand fly species vary greatly depending on the natural environments in the different geographic areas where they are endemic.Ph.chinensis is euryecious and adaptable to different ecologies,and is thus distributed widely in the plain,mountainous,and Loess Plateau regions north of the Yangtze River.Ph.longiductus is mainly distributed in ancient oasis areas south of Mt.Tianshan in the Xinjiang Uygur autonomous region.Ph.wui is the predominant species in deserts with Populus diversifolia and Tamarix vegetation in Xinjiang and the western part of the Inner Mongolia autonomous region.Finally,Ph.alexandri is steroecious and found only in stony desert areas,such as at the foot of the mountains in Xinjiang and the western Hexi Corridor,in Gansu province.This review summarized the relationship between the geographic distribution pattern of the four sand fly species and their geographical landscape in order to foster research on disease distribution and sand fly control planning.Furthermore,some problems that remained to be solved about vectors of VL in China were discussed. 展开更多
关键词 PHLEBOTOMUS Sand fly geographical distribution Vector Visceral leishmaniasis Leishmania donovani Leishmania infantum Ph.chinensis Ph.longiductus Ph.wui Ph.alexandri Ph.mongolensis
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Potential geographical distribution of Rhagoletis pomonella (Diptera: Tephritidae)in China 被引量:5
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作者 Jian Geng Zhi-Hong Li +3 位作者 Edwin G. Rajotte Fang-Hao Wan Xiao-Yu Lu Zhi-Ling Wang 《Insect Science》 SCIE CAS CSCD 2011年第5期575-582,共8页
Apple maggot fly, Rhagoletis pomonella (Walsh) is a major pest causing considerable economic losses of fruits in North America. During the development of international trade, apple maggot fly has become a threat to ... Apple maggot fly, Rhagoletis pomonella (Walsh) is a major pest causing considerable economic losses of fruits in North America. During the development of international trade, apple maggot fly has become a threat to Chinese agriculture. In this study, CLIMEX and ArcGIS were used to predict the potential geographical distribution of apple maggot fly in China. The parameters used in CLIMEX for apple maggot fly were derived from ecological data and the present geographical distribution of apple maggot fly in North America. Then the potential distribution map in China was presented based on the adjusted values of these parameters. The results showed that apple maggot fly has a wide potential distribution area in China; 47.5% of 748 meteorological stations presented high or medium suitability of pest establishment. These high suitable stations are mainly located in northeast, southwest and northwest of China, such as Liaoning, Shandong, Gansu and Shaanxi Provinces. These areas are also the central regions of apple, pear and peach production in China. Two hundred and twenty-five stations (30.1%) in westem and southern China, such as Tibet, Qinghai, Guangdong, Guangxi, Hainan and Taiwan, were unsuitable for establishment of apple maggot fly populations. In order to prevent the introduction of apple maggot fly in China, the present plant quarantine measures should be enhanced, especially in the areas with high suitability for the presence of apple maggot fly. 展开更多
关键词 apple maggot fly ARCGIS CLIMEX potential geographical distribution Rhagoletis pomonella (Walsh)
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Where to donate: The geographical distribution of corporate philanthropy in China 被引量:2
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作者 Li Ji Cunjie Tao Bofu Deng 《China Journal of Accounting Research》 2021年第3期341-361,共21页
An emerging body of literature has demonstrated that corporate philanthropy can be an important part of a company’s business strategy.However,we know relatively little about how companies allocate philanthropic resou... An emerging body of literature has demonstrated that corporate philanthropy can be an important part of a company’s business strategy.However,we know relatively little about how companies allocate philanthropic resources to achieve their strategic targets.Using geographical distribution data on corporate philanthropy in China from 2009 to 2016,we provide robust evidence of companies’revenue-driven regional favoritism.Specifically,companies donate more to regions where they obtain revenue than to other regions.Further evidence suggests that this revenue-driven regional favoritism may have both reputational and political motivations.Further analysis suggests that China’s targeted poverty alleviation policy has compromised revenue-driven regional favoritism while increasing the amount of money donated to poor regions.Overall,we enrich understanding of decision-making on corporate philanthropy.We also demonstrate that companies can use the geographical distribution of corporate philanthropy strategically to obtain consumer and government favor in regions where they operate.The results also provide evidence at the micro company level of the effect of China’s implementation of a targeted poverty alleviation policy. 展开更多
关键词 Corporate philanthropy geographical distribution Reputational motivation Political motivation Targeted poverty alleviation
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Geographical Distribution of Foreign Investment in China: Industrial Clusters and Their Significance 被引量:1
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作者 Jiang Xiaojuan 《China & World Economy》 SCIE 2003年第1期16-24,共9页
The incorporation of massive amounts of foreign direct investment (FDI) has been a major motive force behind the high-speed growth of the Chinese economy over the last decade. A high degree of geographical concentrati... The incorporation of massive amounts of foreign direct investment (FDI) has been a major motive force behind the high-speed growth of the Chinese economy over the last decade. A high degree of geographical concentration in certain of this country is a salient feature of foreign invested enterprises (FIEs). FIEs in some industries are closely clustered in industrial zones ranging from several kilometers to more than 100 km in diameter. Such industrial clusters are a remarkable phenomenon among FDI industries. High FDI concentration is having a striking impact on the competitiveness of the enterprises involved and the regions where they are located. 展开更多
关键词 of on or in geographical distribution of Foreign Investment in China FORM is
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