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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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Impact of climate change on potential habitat distribution of Sciaenidae in the coastal waters of China 被引量:1
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作者 Wen Yang Wenjia Hu +6 位作者 Bin Chen Hongjian Tan Shangke Su Like Ding Peng Dong Weiwei Yu Jianguo Du 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2023年第4期59-71,共13页
Climate change has affected and will continue to affect the spatial distribution patterns of marine organisms.To understand the impact of climate change on the distribution patterns and species richness of the Sciaeni... Climate change has affected and will continue to affect the spatial distribution patterns of marine organisms.To understand the impact of climate change on the distribution patterns and species richness of the Sciaenidae in China’s coastal waters,the maximum entropy model was used to combine six environmental factors and predict the potential distribution of 12 major species of Sciaenidae by 2050s under Representative Concentration Pathways(RCPs)2.6 and 8.5.The results showed that the average area under the receiver operating characteristic curve of the model was 0.917,indicating that the model predictions were accurate and reliable.The main driving factors affecting the potential distribution of these fishes were dissolved oxygen,salinity,and sea surface temperature(SST).There was an overall northward shift in the potential habitat areas of these fishes under the two climate scenarios.The total potential habitat areas of Larimichthys polyactis,Pennahia argentata,and Pennahia pawak decreased under both climate scenarios,while the total habitat area of Johnius belengerii,Pennahia anea,Miichthys miiuy,Collichthys lucidus,and Collichthys niveatus increased,suggesting that these might be loser and winner species,respectively.The expansion rate,contraction rate,degree of centroid change,and species richness in the potential habitats were generally more significant under RCP8.5 than RCP2.6.The mean shift rates of the potential distribution were 41.50 km/(10 a) and 29.20 km/(10 a) under RCP8.5 and RCP2.6,respectively.The changes in Sciaenidae species richness under climate change were bounded by the Changjiang River Estuary waters,with obvious north-south differences.Some waters with increased species richness may become refuges for Sciaenidae fishes under climate change.The richness and habitat area change rate of some aquatic germplasm resources will decrease,meanings that these reserves are more sensitive to climate change,and more attention should be paid to the potential challenges and opportunities for fishery managers.This study may provide a scientific basis for the management and conservation of Sciaenidae in China under climate change. 展开更多
关键词 climate change SCIAENIDAE potential distribution species richness HABITAT
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Predicting Potential Distribution of Tibetan Spruce (Picea smithiana) in Qomolangma (Mount Everest) National Nature Preserve Using Maximum Entropy Niche-based Model 被引量:15
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作者 ZHANG Jiping ZHANG Yili +1 位作者 LIU Linshan NIE Yong 《Chinese Geographical Science》 SCIE CSCD 2011年第4期417-426,共10页
Tibetan spruce (Picea smithiana) is an endemic species of the Himalayas,and it distributes only in a re-stricted area with very low number.To address the lack of detailed distributional information,we used maximum en-... Tibetan spruce (Picea smithiana) is an endemic species of the Himalayas,and it distributes only in a re-stricted area with very low number.To address the lack of detailed distributional information,we used maximum en-tropy (Maxent) niche-based model to predict the species' potential distribution from limited occurrence-only records.The location data of P.smithiana,relative bioclimatic variables,vegetation data,digital elevation model (DEM),and the derived data were analyzed in Maxent.The receiver operating characteristic (ROC) curve was applied to assess the prediction accuracy.The Maxent jackknife test was performed to quantify the training gains from data layers and the response of P.smithiana distribution to four typical environmental variables was analyzed.Results show that the model performs well at the regional scale.There is a potential for continued expansion of P.smithiana population numbers and distribution in China.P.smithiana potentially distributes in the lower reaches of Gyirong Zangbo and Poiqu rivers in Gyirong and Nyalam counties in Qomolangma (Mount Everest) National Nature Preserve (QNNP),China.The species prefers warm temperate climate in mountain area and mainly distributes in needle-leaved evergreen closed to open forest and mixed forest along the river valley at relatively low altitudes of about 2000-3000 m.Model simulations suggest that distribution patterns of rare species with few species numbers can be well predicted by Max-ent. 展开更多
关键词 Picea smithiana maximum entropy niche-based model potential distribution Qomolangma (Mount Ev-erest) National Nature Preserve (QNNP)
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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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Potential Distribution of Alien Invasive Species and Risk Assessment:a Case Study of Erwinia amylovora in China 被引量:4
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作者 CHEN Chen CHEN Juan HU Bai-shi IIANG Ying-hua LIU Feng-quan 《Agricultural Sciences in China》 CAS CSCD 2007年第6期688-695,共8页
Alien invasive species represent a severe risk to biodiversity and economy, as in the case of fire blight (Erwinia amylovora), a bacterial disease that originated in North America, which may be released into new loc... Alien invasive species represent a severe risk to biodiversity and economy, as in the case of fire blight (Erwinia amylovora), a bacterial disease that originated in North America, which may be released into new locations by means of fruit trade. On the basis of the knowledge of Erwinia amylovora's biophysical characteristics and environmental data, the geographic information system (GIS) has been applied to determine areas where Erwinia amylovora can potentially invade China. Temperature and precipitation, during the blossoming period, are considered to be two critical factors affecting the Erwinia amylovora's suitable climatic zones. This spatial modeling approach was validated from a case study in Europe, where the occurrence of Erwinia amylovora has been proven. The model prediction agreed with the occurrence of the bacteria recorded in Europe, and the same procedure has been applied to produce a potential establishment area in China's two preferential apple cultivation regions, Bohai Bay region and Huangtu Altiplano region. It has been found that areas belonging to the high-risk category are more or less the main apple producing areas, accounting for their great economic importance in China. This methodology provides an initial baseline for assessment, prevention, and management of alien species that may become invasive under certain environmental conditions. In addition, this modeling approach provides a tool for policy makers to use, in making decisions on management practices where alien species are involved. 展开更多
关键词 biological invasions Erwinia amylovora GIS potential distribution risk assessment
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Modeling impacts of climate change on the potential distribution of six endemic baobab species in Madagascar 被引量:3
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作者 Jun-Nan Wan Ndungu J.Mbari +6 位作者 Sheng-Wei Wang Bing Liu Brian N.Mwangi Jean R.E.Rasoarahona Hai-Ping Xin Ya-Dong Zhou Qing-Feng Wang 《Plant Diversity》 SCIE CAS CSCD 2021年第2期117-124,共8页
Madagascar,a globally renowned biodiversity hotspot characterized by high rates of endemism,is one of the few remaining refugia for many plants and animal species.However,global climate change has greatly affected the... Madagascar,a globally renowned biodiversity hotspot characterized by high rates of endemism,is one of the few remaining refugia for many plants and animal species.However,global climate change has greatly affected the natural ecosystem and endemic species living in Madagascar,and will likely continue to influence species distribution in the future.Madagascar is home to six endemic baobab(Adansonia spp.,Bombacoideae[Malvaceae])species(Adansonia grandidieri,A.suarezensis,A.madagascariensis,A.perrieri,A.rubrostipa,A.za),which are remarkable and endangered plants.This study aimed to model the current distribution of suitable habitat for each baobab species endemic to Madagascar and determine the effect that climate change will have on suitable baobab habitat by the years 2050 and 2070.The distribution was modeled using MaxEnt based on locality information of 245 occurrence sites of six species from both online database and our own field work.A total of seven climatic variables were used for the modeling process.The present distribution of all six Madagascar's baobabs was largely influenced by temperature-related factors.Although both expansion and contraction of suitable habitat are predicted for all species,loss of original suitable habitat is predicted to be extensive.For the most widespread Madagascar baobab,A.za,more than 40%of its original habitat is predicted to be lost because of climate change.Based on these findings,we recommend that areas predicted to contract in response to climate change should be designated key protection regions for baobab conservation. 展开更多
关键词 Madagascar Adansonia Climate change MAXENT potential distribution
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Integrating potential distribution of dominant vegetation and land use into ecological restoration in the Yellow River Basin,China 被引量:2
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作者 JIAN Sheng-qi ZHU Tian-sheng HU Cai-hong 《Journal of Mountain Science》 SCIE CSCD 2022年第10期2886-2904,共19页
Due to the influence of human activities such as cultivation and urban construction,the ecosystem of the Yellow River Basin(YRB)is subjected to increased vulnerability and even potential risk of destruction.Ecological... Due to the influence of human activities such as cultivation and urban construction,the ecosystem of the Yellow River Basin(YRB)is subjected to increased vulnerability and even potential risk of destruction.Ecological restoration has led to an increase in vegetation,but excessive afforestation conversely results in low survival rate of trees,water shortages,and biodiversity loss.It is of great significance for achieving sustainable development of forests to reasonable revegetation in the region.At present,the potential distribution pattern of dominant species and their mixed forms in the basin has not been effectively studied.This study simulated the potential distribution of dominant vegetation in the YRB based on Maximum Entropy(Max Ent)and Genetic Algorithm for Rule-Set Prediction(GARP)and explored the impact of human interference on it by employing land use as the environmental filter to distinguish the regions of human activities.We further predicted the potential distribution of typically mixed forests and discussed their human interference.The main results are as follows:(1)Except for Caragana korshinskii,all models had good above performance(0.7<the mean AUC<1).Except for Caragana korshinskii,the area under the curve(AUC)for 90%of the models indicated that Max Ent performed better than GARP,and Max Ent easily lead to over-fitting while GARP predicted a wider range.(2)Except for Nitraria tangutorum,the dominant types of vegetation such as Pinus tabulaeformis,Platycladus orientalis,and Hippophae rhamnoides mainly distributed in southern Gansu,Shaanxi,and south-central Shanxi.Among them,the largest suitable area of Artemisia gmelinii and Stipa bungeana(High suitable area)were approximately 56.7×104 km2(38.8%)and 54.7×104 km2(28.5%)with the area occupied by large-scale cultivation being 17.5×104 km2(39.4%)and 18.9×104 km2(48%),respectively,which indicated human activities caused great damage to the core growth regions of these vegetation.(3)Mean temperature of coldest quarter or month mainly constrained the growth of most vegetation in the YRB in terms of temperature,while precipitation of wettest/driest month is one of the dominant factors.However,some vegetation responded differently to other meteorological factors due to niche differences.(4)Most of the mixed forests were distributed in southern Gansu,Shaanxi,and Shanxi provinces;its middle and high suitable areas were mainly concentrated in Shaanxi and southern and central Shanxi,where the cultivated land had occupied most of them.Therefore,the results showed that the restoration of herbaceous vegetation such as Artemisia gmelinii and Stipa bungeana has a high potential and it is appropriate that the measures for afforestation should be concentrated in the areas like the lower reaches of the Weihe,Jinghe,and Beiluo rivers and Luliang Mountain,where the cultivated land overlaps with the high suitable areas of the corresponding vegetation and the mixed forests with less water consumption and wide distribution,such as Caragana korshinskii-Hippophae rhamnoides,Pinus tabulaeformis-Quercus liaotungensis,and Ostryopsis davidiana-Stipa bungeana-Hippophae rhamnoides.The results of this study can provide effective guidance for mixed forest plantations and vegetation conservation in the YRB. 展开更多
关键词 Yellow River potential distribution Land use Mixed forests Vegetation restoration
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The potential distribution of adult Antarctic krill in the Amundsen Sea 被引量:1
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作者 Jianlong FENG Lulu LIU +1 位作者 Qiulin LIU Liang ZHAO 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2022年第4期1566-1577,共12页
Antarctic krill is the key species of ecological system in the Amundsen Sea.At present,the suitable distribution is unobtainable by scientifi c surveys or data from the fi shery.In this paper,the maximum entropy algor... Antarctic krill is the key species of ecological system in the Amundsen Sea.At present,the suitable distribution is unobtainable by scientifi c surveys or data from the fi shery.In this paper,the maximum entropy algorithm(Maxent)was used to obtain the potential distribution of adult Antarctic krill in order to provide useful information and reasonable reference for the policy on protecting potential krill habitats around the Amundsen Sea.Occurrence points and 17 environmental variables were used to simulate the distributions.Results show that the high and moderate suitable habitats lie between 65°S and 72°S in the Amundsen Sea.The high suitable habitat accounts for 8.1%of the total area of the Amundsen Sea.The sea ice persistence(ICE),total phytoplankton(PHYC),and the minimum value of dissolved iron(Fe_min)are the three dominant contributors to the model.Results from the response curves show that Antarctic krill preferred habitats with ICE of 0.42-0.93,PHYC of 2.48-2.77 mmol/m^(3) and Fe_min of(7.10×10^(-5))-(9.45×10^(-5))mmol/m 3.Positive trends existed in the PHYC of the high and moderate suitable habitat,and a positive trend existed in the Fe_min of moderate suitable habitat.However,the probability of presence of Antarctic krill will decrease if the increase of the PHYC and Fe_min continues. 展开更多
关键词 KRILL Amundsen Sea MAXENT potential distribution
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A look into the past, present and future potential distributions of Talinopsis frutescens, a North American endemic lineage closely related to Cactaceae 被引量:1
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作者 Mónica I MIGUEL-VÁZQUEZ Yasser S LÓPEZ DE OLMOS R Gilberto OCAMPO 《Journal of Arid Land》 SCIE CSCD 2020年第1期104-114,共11页
Talinopsis frutescens(Anacampserotaceae,a family that is close related to Cactaceae)is a succulent species endemic to North America.The aim of this study was to explore,using Ecological Niche Modeling(ENM),changes in ... Talinopsis frutescens(Anacampserotaceae,a family that is close related to Cactaceae)is a succulent species endemic to North America.The aim of this study was to explore,using Ecological Niche Modeling(ENM),changes in potential distribution ranges considering different climate scenarios:past conditions during the Last Inter Glacial(LIG)and the Last Glacial Maximum(LGM),the present and projections for 2070(RCP 2.6 to 8.5).A pattern of contraction is observed during the LIG,which agrees with other studies focused in species from arid environments.This pattern was followed by a migration towards the south during the LGM and a possible recent expansion to the north as is observed in the present scenario.All future projections show the same contraction and fragmentation patterns,resulting in three discontinuous areas:the northern part of the Chihuahuan Desert,the southern-central part of the Mexican Plateau,and the smallest one in the Tehuacán-Cuicatlán Valley.Our projections for future scenarios agree with other studies and support that global climate change tends to alter the current distribution of arid environment species. 展开更多
关键词 Anacampserotaceae CARYOPHYLLALES ecological niche modeling succulent plants potential distribution
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ADSORPTION ISOTHERMS AND POTENTIAL DISTRIBUTIONS OF NITROGEN ON VARIOUS ACTIVATED CARBONS 被引量:3
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作者 LI Xiang LI Zhong LUO lingai 《Chinese Journal of Reactive Polymers》 2005年第1期8-13,共6页
The adsorption isotherms of four activated carbons (Norit Rill, Chemviron BPL, Monolit, and Ambersorb-572) have been examined by nitrogen adsorption at 77.5 K. A method for adsorption potential distribution calculat... The adsorption isotherms of four activated carbons (Norit Rill, Chemviron BPL, Monolit, and Ambersorb-572) have been examined by nitrogen adsorption at 77.5 K. A method for adsorption potential distribution calculation has been proposed based on the adsorption isotherms. This distribution provides information about possible changes in the Gibbs free energy caused by the energetic and geometrical heterogeneities of an activated carbon as well as by the adsorbate-related entropic effects. The general character of the adsorption potential distribution is clearly visible by its simple relation to the micropore and mesopore distribution, 展开更多
关键词 Adsorption isotherms Adsorption potential distributions MICROPORE STRUCTURE Structural heterogeneity.
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Predicting Ecological Distribution of the Toxic Dinoflagellate Alexandrium minutum in China Sea Using Ecological Niche Modeling 被引量:1
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作者 WANG Changyou ZHENG Ping +4 位作者 GU Haifeng LUO Zhaohe LUO Zhuhua MAO Longjiang ZHANG Yuanzhi 《Journal of Ocean University of China》 SCIE CAS CSCD 2023年第4期1119-1128,共10页
Alexandrium minutum from the China Sea produces a range of toxins and causes damage to the local ecosystems and aquaculture.This is essential to understand environmental factors affecting potential distribution.Potent... Alexandrium minutum from the China Sea produces a range of toxins and causes damage to the local ecosystems and aquaculture.This is essential to understand environmental factors affecting potential distribution.Potential distributions of A.minutum in the China Sea were predicted based on maximum entropy modeling,and dominant environmental variables were studied through analyses of variable contributions and response curves.The results showed that highly suitable areas were mainly located in the southwest of the Yellow Sea,the Laizhou Bay,and north of Haizhou Bay.The coast of the South China Sea was predicted as a low-suitability area,and the coast of the East China Sea as an unsuitable area.Mean temperature of the coldest month(T_min)had the largest drop in permutation importance but a low percent contribution.The probability of presence of A.minutum increased with increasing concentration of nitrate(NO3−)and annual mean temperature(T_ann)over a wide range of them.The response curves decreased with increasing concentration of phosphate(PO43−)and ratio of NO_(3)^(−)to PO_(4)^(3−)(N_P_ratio)when PO_(4)^(3)−is above 0.049μmolL^(-1) and N_P_ratio above 4,indicating that low values of PO_(4)^(3−) concentration and N_P_ratio favour the occurrence of A.minutum.As a predictor,the variance of annual temperature(T_Var)had the highest percent contribution and gains.PO_(4)^(3−) was predicted to have much more information than the other variables,and exhibited the second largest drop in permutation importance and percent contribution.The T_Var and PO_(4)^(3−) are the most important dominant predictor variables. 展开更多
关键词 Alexandrium minutum MaxEnt habitat suitability environmental variable potential distributions
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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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Charge transfer and variation of potential distributions in the formation of 4, 4'-bipyridine molecular junction
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作者 李宗良 邹斌 +1 位作者 闫循旺 王传奎 《Chinese Physics B》 SCIE EI CAS CSCD 2007年第5期1434-1439,共6页
In this paper the charge transfer and variation of potential distribution upon formation of 4, 4'-bipyridine molecular junction have been investigated by applying hybrid density-functional theory (B3LYP) at ab init... In this paper the charge transfer and variation of potential distribution upon formation of 4, 4'-bipyridine molecular junction have been investigated by applying hybrid density-functional theory (B3LYP) at ab initio level. The numerical results show that there exist charge-accumulation and charge-depletion regions located at respective inside and outside of interfaces. The variation of potential distribution is obvious at interfaces. When distance between electrodes is changed, the charge transfer and variation of potential distribution clearly have distance-dependent performance. It is demonstrated that the contact structure between the molecule and electrodes is another key factor for dominating the properties of molecular junction. The qualitative explanation for experimental results is suggested. 展开更多
关键词 charge transfer potential distribution molecular junction
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Electric potential distribution near nanocone arrays on metal substrates
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作者 黄晓菁 游荣义 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第5期636-640,共5页
Based on the nanostructured surface model,where conical nanoparticle arrays grow out symmetrically from a plane metal substrate,a theoretical model of the local electric potential near nanocones is built when a unifor... Based on the nanostructured surface model,where conical nanoparticle arrays grow out symmetrically from a plane metal substrate,a theoretical model of the local electric potential near nanocones is built when a uniform external electric field is applied.In terms of this model,the electric potential distribution near the nanocone arrays is obtained and given by a curved surface using a numerical computation method.The computational results show that the electric potential distribution near the nanocone arrays exhibit an obvious geometrical symmetry.These results could serve as a basis for explaining many abnormal phenomena,such as the abnormal infrared effects(AIREs) which are found on nanostructured metal surfaces,as well as a reference for investigating the applications of nanomaterials,such as nanoelectrodes and nanosensors. 展开更多
关键词 nanocone arrays nanostructured metal surface electric potential distribution
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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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Potential Geographic Distribution of Oriental Fruit Fly in Jiangxi Province
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作者 LIU Jian-hong XIONG Xiao-zhen +2 位作者 PAN Yong-zhi XIONG Zhong-ping YANG Li-ying 《Agricultural Science & Technology》 CAS 2010年第6期155-158,共4页
[Objective] The aim was to effectively monitor and manage oriental fruit fly.[Method] Maxent model and ArcGIS were used to predict potential geographic distributions of the oriental fruit fly based on associations bet... [Objective] The aim was to effectively monitor and manage oriental fruit fly.[Method] Maxent model and ArcGIS were used to predict potential geographic distributions of the oriental fruit fly based on associations between known occurrence records and a set of environmental variables.[Result] The suitable areas for Bactrocera dorsalis infestations were mainly restricted to central and southern Jiangxi Province,with Latitude ranged from 24 to 28°N.Northeast Jiangxi,Northwest Jiangxi and the regions bording upon Yangtse River were predicted as unsuitable for Bactrocera dorsalis.The fit for the model as measured by AUC was high,with value of 0.978 for the training data and 0.965 for the test data,indicating the high level of discriminatory power for the Maxent.A jackknife test in Maxent indicated that mean temperature of coldest quarter with highest gain value was the most important environmental variable that restricted the expansion to north Jiangxi Province.[Conclusion] Further research into the biology of the species and their ability to overcome barriers was necessary to explain niche differentiation and better understand invasion risk. 展开更多
关键词 Fruit fly Bactrocera dorsalis Ecological niche model potential distribution MAXENT
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Prediction of Potential Distribution of Quadrastichus erythrinae Kim in China
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作者 Zhang Junzhong Liu Jianhong +1 位作者 Yang Liying Dan Wenli 《Plant Diseases and Pests》 CAS 2014年第2期1-3,21,共4页
Based on Maxent niche model and combined with ArcGIS,the suitable area range for Quadrastichus erythrinae Kim in China was predicted in the paper.The results showed that high suitable area for Q. erythrinae in China i... Based on Maxent niche model and combined with ArcGIS,the suitable area range for Quadrastichus erythrinae Kim in China was predicted in the paper.The results showed that high suitable area for Q. erythrinae in China included most northeast coastal areas of Hainan Island,partial southern coastal area of Guangdong Province,partial northwestern coastal area and partial southeast coastal area of Taiwan Island; moderate suitable area included partial area of Hainan,some contiguous areas of Guangxi and Guangdong,most areas of Guangdong,partial area of Fujian and Taiwan; low suitable area included partial area from northwestern coast to inland of Hainan Island,west coastal area of Taiwan Island,most area in Guangxi,partial areas in Guangdong,Fujian and Yunnan. 展开更多
关键词 Quadrastichus erythrinae Kim Maxent niche model potential distribution prediction
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Determining the Boundary of Molten Electrolyte and Aluminum in Electrolytic Cells by Detecting Their Vertical Distribution of Potential
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作者 CHANG Liming ZHANG Zhaohui +4 位作者 ZHAO Xiaoyan BIAN Xinxiao ZUO Zengyang LU Hui LAO Dabao 《Instrumentation》 2022年第3期59-64,共6页
Aluminum production is a high energy consumption process so that maintaining fundamental compositions in balance and optimal conditions are essential.The molten electrolyte and melted aluminum are primary materials an... Aluminum production is a high energy consumption process so that maintaining fundamental compositions in balance and optimal conditions are essential.The molten electrolyte and melted aluminum are primary materials and their boundary needs to be monitored from time to time.An automatic measurement technic is presented in the paper to substitute for the traditional manual measurement work that is dull,poor efficiency and dangerous for operators.The boundary forming mechanism is analyzed,the vertical profile of electric potential is simulated,an automatic instrument is developed to sense the potential distribution,and a strategy is provided to identify the boundary according to the potential curves.Finally,some practical results are compared with manual measurements,which shows good consistency. 展开更多
关键词 Aluminum Electrolytic Cell Boundary of Molten Materials Electric potential distribution Measurement Online
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Projected impacts of climate change on the habitat of Xerophyta species in Africa
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作者 Vincent Okelo Wanga Boniface KNgarega +9 位作者 Millicent Akinyi Oulo Elijah Mbandi Mkala Veronicah Mutele Ngumbau Guy Eric Onjalalaina Wyclif Ochieng Odago Consolata Nanjala Clintone Onyango Ochieng Moses Kirega Gichua Robert Wahiti Gituru Guang-Wan Hu 《Plant Diversity》 SCIE CAS CSCD 2024年第1期91-100,共10页
Climate change poses a serious long-term threat to biodiversity.To effectively reduce biodiversity loss,conservationists need to have a thorough understanding of the preferred habitats of species and the variables tha... Climate change poses a serious long-term threat to biodiversity.To effectively reduce biodiversity loss,conservationists need to have a thorough understanding of the preferred habitats of species and the variables that affect their distribution.Therefore,predicting the impact of climate change on speciesappropriate habitats may help mitigate the potential threats to biodiversity distribution.Xerophyta,a monocotyledonous genus of the family Velloziaceae is native to mainland Africa,Madagascar,and the Arabian Peninsula.The key drivers of Xerophyta habitat distribution and preference are unknown.Using 308 species occurrence data and eight environmental variables,the MaxEnt model was used to determine the potential distribution of six Xerophyta species in Africa under past,current and future climate change scenarios.The results showed that the models had a good predictive ability(Area Under the Curve and True Skill Statistics values for all SDMs were more than 0.902),indicating high accuracy in forecasting the potential geographic distribution of Xerophyta species.The main bioclimatic variables that impacted potential distributions of most Xerophyta species were mean temperature of the driest quarter(Bio9)and precipitation of the warmest quarter(Bio18).According to our models,tropical Africa has zones of moderate and high suitability for Xerophyta taxa,which is consistent with the majority of documented species localities.The habitat suitability of the existing range of the Xerophyta species varied based on the climate scenario,with most species experiencing a range loss greater than the range gain regardless of the climate scenario.The projected spatiotemporal patterns of Xerophyta species help guide recommendations for conservation efforts. 展开更多
关键词 AFRICA Climate change MaxEnt model potential suitable distribution Velloziaceae Xerophyta
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Analysis on Suitable Distribution Area of Oriental Fruit Fly (Bactrocera dorsalis) Based on GARP Ecological Niche Model
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作者 刘建宏 熊小真 +2 位作者 杨丽英 熊忠平 潘涌智 《Plant Diseases and Pests》 CAS 2010年第6期34-38,共5页
[Objective] The paper was to provide the scientific basis for effective monitoring and early warning on oriental fruit fly in Jiangxi Province.[Method] Using the distribution data and environmental factor data of orie... [Objective] The paper was to provide the scientific basis for effective monitoring and early warning on oriental fruit fly in Jiangxi Province.[Method] Using the distribution data and environmental factor data of oriental fruit fly,the potential distribution area of oriental fruit fly in Jiangxi Province was predicted by GARP ecological niche model.[Result]The total suitable area for oriental fruit fly in Jiangxi province was over two thirds of the whole province.Most areas in southern Jiangxi basin ranged from 24° to 26° N were the high suitable area for oriental fruit fly,where the annual average temperature was 19-20℃.Part areas in north Ganzhou and small areas in southwest Ji'an,Wuzhou,Yingtan,southeast Shangrao ranged from 26° to 27° N were the moderate suitable areas for oriental fruit fly,where the annual average temperature was 18-19℃.The low suitable area was ranged from 26° to 30° N including Binhu,Ganjiang River,Wuhe,Yuanshui area and Southwestern Mountain of Jiangxi Province,where the annual average temperature was 17-18℃.Northeast and northwest areas in Jiangxi Province and coastal areas along the Yangtze River was predicted to be non-suitable area for oriental fruit fly,where the annual average temperature was 16-17℃.[Conclusion] The results showed that the actual distribution of oriental fruit fly basically was consistent with the distribution predicted by GARP. 展开更多
关键词 Oriental fruit fly GARP potential distribution area JIANGXI
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