Potential Distribution Model Research Articles

Assessing the impact of ground ice degradation on high mountain lake environments (Lago Nero catchment, Swiss Alps)

In high mountain hydrosystems, glacial meltwater composition is potentially affected by the degradation of alpine permafrost terrains and ground ice bodies releasing atmospheric pollutants that have been stored in permafrost terrains for several decades. In this study we investigate the potential local permafrost distribution as well as the physical and chemical ground water characteristics of the periglacial environments of the Lago Nero (“Black Lake”) catchment, a high alpine basin located in the Southern Swiss Alps. Our approach combines in situ geological and geomorphological mapping, potential permafrost distribution modelling, a thermal monitoring of ground surface temperatures and the study of the meltwater chemistry of an intact rock glacier (active or inactive rock glacier, i.e. containing ice) and several perennial ice patches. The comparison of elemental concentrations between the periglacial terrains and the Lago Nero outflow unveiled the presence of atmospheric chemicals in the meltwater. Considering the temporal concordance between the recorded peak of sulphur deposition between 1965 and 1980 and the last identified period of positive glacier mass balance occurred in the region (1961–1985), we argue that the enhanced melting of ground ice related to the recent severe warming is nowadays releasing “legacy” pollutants that have been stored in the cryosphere for several decades.

Projected impact of global warming on the distribution of two pocket mouse species with implications on the conservation of Heteromys nelsoni (Rodentia: Heteromyidae)

We explain through potential distributions and changes in altitudinal variation, the possible impacts of climate change in an endangered micro-endemic rodent of Mexico with narrow altitudinal range, Heteromys nelsoni and a rodent with a wide distributional and altitudinal range, Heteromys goldmani. We obtained historical and current records of both Heteromys species. Potential distribution models were generated using Maxent, including altitudes for each species and bioclimatic layers. We determined the Extent of Occurrence and Area of Occupancy for H. nelsoni according to the criteria of the IUCN in order to generate information about its risk status. The altitude is not a variable that determines a shift in the distribution caused by climate change. In contrast, the temperature and precipitation are important for the potential distribution of both Heteromys species. The future changes in climatic conditions will reduce the area of suitable habitat for H. nelsoni and will favor the presence of H. goldmani. The distribution surface is not greater than 33.44 km2 for H. nelsoni. Therefore, is urgent to re-evaluate their conservation status by the IUCN, mainly in its B criterion, and to take specific actions for their conservation. We suggest the creation of a terrestrial protected area.

Climatic constraints and the distribution of Patagonian mice

Abstract We generated potential distribution models for 14 sigmodontine rodent species that inhabit the Andean–Patagonian forest region and adjacent areas, and retrieved the main climatic variables responsible for these models. Our main objective was to compare these climatic variables and the distribution patterns generated for each species, and explore the effects of the physical environment in shaping the composition of rodent communities in the area. We retrieved a total of 1,215 records of species presence from 580 sites. Maxent was used to generate potential distribution models for the 14 rodent species studied. We used a total of 20 variables obtained from the WorldClim database, including elevation and 19 bioclimatic variables, in addition to normalized difference vegetation index (NDVI) and enhanced vegetation index (EVI). Our results showed a clear discrimination between two groups of rodents, one concentrated in the western part of our study area, with more humid climate and a rugged mountainous and discontinuous habitat, and another inhabiting the eastern, drier part of our study area, which appears to be more uniform in habitat characteristics. These groups showed a mosaic of phylogenetically non-related species from different tribes, that probably arrived or expanded into Patagonia during the last millennia. The overlap of all models showed the forest-steppe ecotone east of Nahuel Huapi Lake and south to −43° latitude as the area with the highest species richness (8–11 species). All species showed a high correspondence with temperature and precipitation that define patterns at a landscape scale, with little to very little information contained in the typical vegetation variables that would define local conditions. En este trabajo generamos modelos de distribución potencial para cada especie de roedor sigmodontino que habita la región de los bosques andino-patagónicos y áreas adyacentes, identificando las principales variables climáticas que influyen en dichas distribuciones. Nuestro principal objetivo fue comparar las variables climáticas y los patrones de distribución generados para cada especie, y explorar los efectos del entorno físico en la composición de los ensambles de especies. Recopilamos un total de 1215 registros de presencia de especies de 580 sitios. Se utilizó MaxEnt para generar los modelos de distribución potencial de las 14 especies de roedores estudiadas, con 20 variables obtenidas de la base de datos WorldClim, incluida la elevación, 19 variables bioclimáticas, además del NDVI y EVI. Nuestros resultados muestran una clara discriminación entre dos grupos de roedores, uno concentrado en el área occidental, con un clima más húmedo y montañoso, y otro que habita en el área más seca del este. Curiosamente, estos grupos muestran un mosaico de especies, filogenéticamente no relacionadas y de diferentes tribus, que probablemente llegaron o se expandieron en la Patagonia durante los últimos milenios. La superposición de todos los modelos muestra el ecotono bosque-estepa, al este del lago Nahuel Huapi y hacia el sur hasta los -43°, como la zona más rica en especies (8 a 11 especies). Todas las especies muestran una alta correspondencia con las variables ambientales (temperatura y precipitación) que definen patrones a escala del paisaje, con muy poca información contenida en las variables típicas de la vegetación que definirían las condiciones locales.

Present Range of Tuva Mountain Vole Alticola tuvinicus Ognev, 1950 (Review of Environmental Conditions and Modeling)

This study analyzes the present distribution of the Tuva mountain voles based on literary data, museum collections, and our own materials. A bioclimatic model of potential species distribution has been constructed using 25 localities identified as having Tuva mountain voles in Russia and Mongolia. It is shown that the species range of the Tuva voles consists of three large isolated parts: the northern one, located mainly in Khakassia; southern, located in Tuva and the adjacent territory of Mongolia; and a small area on the northern shore of the Khuvsgul Lake in Mongolia. The examination of habitats of the Tuva mountain voles in the territory of Khakassia has shown that in recent decades there has been a significant decrease in the number of inhabited sites, which indicates a significant decline in population and intensification of fragmentation of the northern part of the range of the Tuva mountain vole.

Potential distribution and areas for conservation of four wild felid species in Mexico: Conservation planning

Knowing the potential distribution of species helps to focus conservation efforts more effectively, mainly when dealing with endangered species. The aim of this study was to generate potential distribution models for four species of small wild felids in Mexico (Leopardus pardalis, Leopardus wiedii, Lynx rufus and Puma yagouaroundi). The models were generated based on felids presence records, and topographic, anthropic and vegetation drivers. We used 473 records (171 for L. pardalis, 140 for L. wiedii, 86 for L. rufus and 76 for P. yagouaroundi) to build eleven models per species to then select the three with the best performance and included them in ensemble models. These were based on the formula of the weighted average, which considers the performance of the algorithms evaluated with a subsample of testing records, from which the area under the curve is calculated. In this way, in the ensemble model the consistent zones between algorithms are included, but the one with the best performance predominates. The species with the largest potential distribution area was L. pardalis with 34.3% of the national territory, while L. rufus had the smallest area (14.3%). In the four species a unique set of variables was identified that influence the probability of presence, however the altitude, the arid vegetation and the population density were important variables for three of the four species. We verified our models with recently published presence records. The results of this study reflect a robust analysis of the current and potential distribution of four species of wild felids in Mexico. In addition to being the first step to develop effective conservation strategies at national and local levels.

EVALUATION OF THE DISTRIBUTION MODELS OF "BURITI" AND "PARATUDO", ARBOREAL SPECIES OF THE PANTANAL, WITH DATA OF THE CLIMATE OF THE QUATERNARY AND THE PRESENT

During the Quaternary, climatic variations caused changes in the size of vegetation formations in the Pantanal, promoting the expansion of seasonal forests at the beginning of the Holocene. Climatic conditions change the patterns of vegetation diversity on continental scales. Mauritia flexuosa L. f., The "Buriti", is a palm tree that explores humid environments with acid soils. While, Tabebuia aurea (Silva Manso) Benth. &Hook.f. ex S.Moore is a species of monodominant occurrence in the Pantanal in extensive areas locally denominated as "paratudal". Data sets of past eras have contributed to the study of plant species biogeography. The models of the potential distribution of these species were generated from the algorithm of the Maxent program with climatic data set of the Last Glacial Maximum (ca 22,000 years AP), Holocene Medium (ca. 6,000 years AP) and present time in two different versions. Potential distribution models with climatic packets from the present in the newer version presented areas of environmental suitability greater than in the older version. In the Holocene Middle and Late Glacial Maximum periods, the areas of environmental suitability were higher than in the newer present version. Many studies on climatic variations on the South American continent confirm the suggestions of the proposed models. The areas of environmental suitability of the species treated in the present are smaller in comparison with Last Glacial Maximum and Average Holocene. The species presented a potential distribution according to the biogeographic history of South America.

Predicting the potential distribution of striped hyena Hyaena hyaena in Iran

Predictive potential distribution modelling is crucial in outlining habitat usage and establishing conservation management priorities. Species distribution models estimate the relationship between species occurrences and environmental and spatial characteristics. Herein, we used maximum entropy distribution modelling (MaxEnt) for predicting the potential distribution of the striped hyena Hyaena hyaena in the entire country of Iran, using a number of occurrence records (i.e. 118) and environmental variables derived from remote sensing. The MaxEnt model had a high success rate according to test AUC scores (0.97). Our results are congruent with previous studies, suggesting that mountainous regions in northern and western Iran and the plain regions in central and eastern Iran are suitable habitats for H. hyaena.

PEMODELAN KONTINU 2-D BERBASIS EFEK ELEKTOKINETIK DENGAN FINITE ELEMENT PENDEKATAN GALERKIN

Method refers to a measurement of naturally electric potential on the surface. Self Potential is one of thegeophysical methods that can be used to identify fluid flow in the subsurface. Finite element method hasbeen used to fluid flow velocity modeling, current source, and potential distribution modeling based onelectrokinetic effect in 2-D profile. The sign of potensial respon (negative or positive) is an important factorfor the interpretation of self-potential anomalies. Finite element method is one of the numerical methods forsolve the boundary value problems and the boundary conditions in the form of differential equations in SelfPotentialmodeling

Spatial incongruence in the species richness and functional diversity of cricetid rodents.

Biodiversity is multidimensional and different mechanisms can influence different dimensions. The spatial distribution of these dimensions can help in conservation decisions through the location of complementary areas with high diversity. We analyzed congruence in spatial patterns of species richness and functional diversity of cricetid rodents in the state of Oaxaca, southern Mexico, at different scales, and environmental variables related. Potential distribution models were produced for 49 species of cricetids in Maxent and superimposed to obtain potential communities in cells of 25, 50,100, 200 and 400 km2. We estimated species richness (SR) and functional diversity (SES.FD) eliminating the species richness effect through null models. The patterns and spatial congruence of species richness and functional diversity are described. The relationships between the environmental variables (elevation, temperature, precipitation, net primary productivity and potential evapotranspiration) and the SR and SES.FD were explored using Generalized Linear Models (GLMs) and Generalized Additive Models (GAMs). The highest species richness was found in mountainous ecosystems while the highest functional diversity was in tropical forests, revealing a spatial incongruence among these components of biodiversity (r = -0.14, p = 0.42; Pearson correlation). The locations of the cells of low congruence varied according to spatial resolution. In univariate models, elevation was the variable that best explained species richness (R2 = 0.77). No single variable explained the functional diversity; however, the models that included multiple environmental variables partially explained both the high and low functional diversity. The different patterns suggest that different historic, ecological and environmental processes could be responsible for the community structure of cricetid rodents in Oaxaca. These results indicate that one great challenge to be met to achieve more effective planning for biological conservation is to integrate knowledge regarding the spatial distribution of different dimensions of biodiversity.

Climatic niche comparison across a cryptic species complex.

According to current molecular evidence, the Chionaspis pinifoliae heterophyllae species complex has been recognized as 10 cryptic species. In this study, we construct potential distribution maps for seven cryptic species based on climatic variables. This was done to assess the main environmental factors that have contributed to the distribution map and test the degree of niche overlap across the seven cryptic species. We used MaxEnt to build the climatic niche models under climatic variables. For these models, the similarities and differences of the niches across the cryptic species were estimated. By comparing the potential distribution model of each cryptic species, our results suggested parapatric, sympatric and allopatry populations for this cryptic species complex. Our results showed high variability in niche overlap, and more often niche conservatism than niche divergence. The current species delimitation of the Chionaspis pinifoliae heterophyllae complex by molecular information and the hypothesis that the niche overlap in the sympatric population is higher than that of the allopatry population were supported based on the findings. This study will provide baseline data and a distribution range to facilitate the further control of these insects and formulate quarantine measures.

Modeling Cedrus atlantica potential distribution in North Africa across time: new putative glacial refugia and future range shifts under climate change

In recent years, species distribution models have been used to gain a better understanding of past and future range dynamics of species. Here, we focus on a keystone species of the North African forest ecosystem (Cedrus atlantica) by calculating a consensus model of the species current geographic potential distribution in North Africa, based on a weighted average method aiming to decrease uncertainty. The consensus model is obtained using seven species distribution model algorithms taking into account 24 environmental variables. The model is then applied to several past and future time slices. Past projections refer to the Middle-Holocene and the Last Glacial Maximum, whereas those of future are related to expect conditions around 2050 and 2070. We found that the current potential distribution of Cedrus atlantica is larger than its actual geographical distribution. For some explanatory variables, the analysis revealed their importance for the species current distribution. Among all obtained models, that for the Middle-Holocene showed the maximum expansion of the species potential distribution. The Last Glacial Maximum model provided new putative glacial refugia of Cedrus atlantica, not shown by other mechanistic models and palaeorecord localities. Future projections revealed a significant and fast contraction with shifting in altitude of the species range, showing more fragmented areas and even species disappearance in many North African localities. These findings can help to restore cedar forests and conserve them by ex situ strategies according to the future defined refugia in North Africa. Attention should be paid to the resolution of related output maps, the current biotic interactions, and those that may arise under climate change.

A new natural hybrid in the genus Laelia (Orchidaceae) from Oaxaca, Mexico

A new natural hybrid in the genus Laelia, from the Mixtec region in Oaxaca state, Mexico, is described and illustrated. Laelia × tlaxiacoensis is the name given to a hybrid between L. albida and L. furfuracea. Both Laelia species are sympatric in the region where the hybrid comes from and they coincide in their bloom season. The hybrid looks like a plant of L. albida bearing an inflorescence from L. furfuracea. Laelia × tlaxiacoensis differs from L. albida by its lilac flowers, less floriferous raceme, rhombic and erect petals, and the labellum narrower at the mid-lobe than across the lateral lobes spread out. From L. furfuracea, the hybrid differs by its longer inflorescence, proportionally narrower leaves, orbicular labellum, and straight column. Information about distribution, habitat, phenology, and conservation status for the new hybrid is provided. A potential distribution model was generated for the putative parents of L. × tlaxiacoensis, showing the region where both become sympatric and the occurrence of the new hybrid in it.

3D analytical modeling and electrical characteristics analysis of gate-engineered SiO2/HfO2-stacked tri-gate TFET

In this paper, we have incorporated the novel concept of gate material engineering in a three-dimensional tri-gate TFET structure with SiO2/HfO2-stacked gate oxide to reap the dual benefits of triple gate material and dielectric engineering in a single device. A detailed 3D analytical modeling of electrostatic potential distribution and electric field of the proposed structure is developed here solving 3D Poisson’s equation with suitable boundary conditions. Tunneling current is then extracted by integrating the band-to-band tunneling generation rate over the volume of the device. A comprehensive performance analysis of the present structure is analyzed in terms of potential profile, electric field and ON-current characteristics of the device by varying several parameters such as channel length, channel thickness, oxide thickness, applied gate and drain bias voltages. An overall performance comparison of the proposed structure with dual and single gate material equivalent tri-gate TFET structures with and without high-k gate stack is also demonstrated to explore the functional efficiency of the present structure. The results of the derived analytical model are compared with SILVACO ATLAS simulated data verifying the accuracy of our model in order to validate it for establishing the superiority of the structure.

Analysis of the Distribution of Rock Agamas of Genus Paralaudakia Baig, Wagner, Ananjeva et Böhme, 2012 (Agamidae: Sauria, Reptilia): Use of Maxent Modeling

Predictive potential distribution modeling is of increasing importance in modern herpetological studies for determination of environmental and conservation priorities. In this work, the results of analysis and predictions of the potential distribution of four species of rock agamas of the genus Paralaudakia Baig, Wagner, Ananjeva et Bohme, 2012: P. caucasia, P. microlepis, P. lehmanni, and P. erythrogaster, are given, using the distribution models in Maxent ( www.cs.princeton.edu/~schapire/maxent ). We attempt a comparison of the contribution of bioclimatic factors and the characteristics of biotope distribution for parapatric and sympatric caucasia–microlepis–erythrogaster species group. The overlap of the niches of the Caucasian agama with all the species studied, which, according to the models, can be parapatric or sympatric, is minimal. The maximum overlapping of ecological niches is shown for sympatric species P. microlepis and P. erythrogaster (0.47), as well for spatially separated pairs P. lehmanni and P. erythrogaster (0.39) and P. lehmanni and P. microlepis (0.33). The features and potential distribution of rock agamas of the genus Paralaudakia are studied; a comparative analysis of four species of this genus using the Maxent software and an analysis of their ecological niches based on 19 variable bioclimatic (BIO 1–19) and 8 solar (BIO 10–27) parameters with a minimum resolution of 10 arc-minutes was conducted. The geographical coordinates of locations of findings from the species distribution ranges of P. caucasia (Eichwald, 1831), P. erythrogaster (Nikolsky, 1896), P. lehmanni (Nikolsky, 1896), and P. microlepis (Blanford, 1874) were taken into account in the analysis of bioclimatic factors. A significant contribution to modeling the range of the species studied is made by precipitation of the warmest and coldest quarters of the year.

Shifts in Climatic Niche Occupation in Astrophytum Coahuilense (H. Möller) Kayser and Its Potential Distribution in Mexico

It has frequently been reported that species with strong niche conservatism will not be able to adapt to new climatic conditions, so they must migrate or go extinct. We have evaluated the shifts in climatic niche occupation of the species Astrophytum coahuilense and its potential distribution in Mexico. We understand niche occupation as the geographic zones with available habitats and with the presence of the species. To assess shifts in climatic niche occupation, we used niche overlap analysis, while potential distribution modeling was performed based on the principle of maximum entropy. The results indicate that this species presents a limited amplitude in its climate niche. This restriction of the climatic niche of A. coahuilense limits its ability to colonize new geographical areas with different climatic environments. On the other hand, the potential distribution models obtained from the present study allow us to identify potential zones based on the climatic requirements of the species. This information is important to identify high priority areas for the conservation of A. coahuilense.

Theoretical analytic model for RESURF AlGaN/GaN HEMTs**Project supported by the National Basic Research Program of China (Grant No. 2015CB351906), the National Natural Science Foundation of China (Grant No. 61774114), the Key Program of the National Natural Science Foundation of China (Grant No. 61334002), and the 111 Project, China (Grant No. B12026).

In this paper, we propose a two-dimensional (2D) analytic model for the channel potential and electric field distribution of the RESURF AlGaN/GaN high electron mobility transistors (HEMTs). The model is constructed by two-dimensional Poissonʼs equation with appropriate boundary conditions. In the RESURF AlGaN/GaN HEMTs, we utilize the RESURF effect generated by doped negative charge in the AlGaN layer and introduce new electric field peaks in the device channels, thus, homogenizing the distribution of electric field in channel and improving the breakdown voltage of the device. In order to reveal the influence of doped negative charge on the electric field distribution, we demonstrate in detail the influences of the charge doping density and doping position on the potential and electric field distribution of the RESURF AlGaN/GaN HEMTs with double low density drain (LDD). The validity of the model is verified by comparing the results obtained from the analytical model with the simulation results from the ISE software. This analysis method gives a physical insight into the mechanism of the AlGaN/GaN HEMTs and provides reference to modeling other AlGaN/GaN HEMTs device.

Nitzschia martiana (C.A. Agardh) Van Heurck (Bacillariophyceae): distribution modelling and new records along the Brazilian coast

Benthic diatoms that produce and live inside mucilage tubes are prominent pioneer colonizers of marine substrata. This adaptation is an ecological strategy related to mechanical protection against wave action and desiccation. In this article, we identify Nitzschia martiana based on morphological and ultrastructural analyses from several samples, collected from different localities. We also analysed the potential distribution model of the species to identify potential areas along the Brazilian coast with high environmental suitability for its occurrence. The distribution modelling, associated with our wide sampling, allowed us to present a robust characterization of the distribution of N. martiana along the Brazilian coast. Previous records were restricted to the coast of the states of Paraná, Santa Catarina, and Pernambuco. Our results confirmed the occurrence of the species in 14 new localities, over a temperature range of 18–27°C, always occurring as macroscopic tufts, in regions exposed to direct sunlight during low tide periods, on sand, coral reefs and rocks.

Numerical Research for the Start Control and Final Observation Problem in Model of the Distribution of Potentials in a Crystalline Semiconductor

The article considers the numerical research of the mathematical model of control of potential distribution in a crystalline semiconductor. This model based on the problem of start control and final observation by weak generalized solutions of mathematical model of potential distribution in a crystalline semiconductor. This model belongs to the class of mathematical models based on semilinear Sobolev type equations with $p$-coercive and $s$-monotonous operators. We have shown the existence and uniqueness of a weak generalized solution of the investigated model with the initial condition of Showalter--Sidorov and found sufficient conditions the existence of a solution to the problem of start control and final observation. We construct the algorithm of the numerical method to solve the problem of start control and final observation for the model of control potential distribution in a crystalline semiconductor, based on method of decomposition and method of Galerkin. Computational experiments are given.

Distribución potencial de Sanionia spp. en dos momentos del Holoceno en península Fildes isla Rey Jorge Antártica

The first potential distribution model for mosses, Sanionia spp., in Fildes peninsula, South Shetland, Antarctica was generated using the maximum entropy algorithm (Maxent) for two Holocene moments. The potential distribution model of Sanionia spp. calibrated for the present time (DPM S. Present) was executed for past periods, 11 ka (DPM S. 11 ka) and 6 ka (DPM S. 6 ka). Knowing that the ecological niche is a set of biotic and abiotic conditions where the species is able to remain stable in population size, abiotic variables, such as topography and temperature were used for the calibration of the DPM S. Present. The topographic variables are elevation, slope and exposure, constructed based on a digital elevation model of the ice-free area of the Fildes peninsula. For the DPM S. 11 ka and DPM S. 6 ka the variables are constructed with the data of the current digital elevation model modified according to the reconstruction of ice sheet position, sea level and temperature anomaly values obtained from the ice core on James Ross island. The model established that the probability of presence in the Fildes peninsula for the current moment is 29.5%, for the moment 6 k the probability of presence is 58.9% and for the moment 11 ka the probability is 69.9%. The probability of presence of Sanionia spp. in Fildes peninsula occurs with temperatures between -2.4°C and -3.0°C, heights below 130 m, slopes below 52% and in south - east, south - west and northwest aspect

双花木属植物潜在分布区模拟与分析

PDF HTML阅读 XML下载 导出引用 引用提醒 双花木属植物潜在分布区模拟与分析 DOI: 10.5846/stxb201805311203 作者: 作者单位: 中南林业科技大学林木遗传育种实验室,四川大学生命科学学院,中南林业科技大学林木遗传育种实验室,中南林业科技大学林木遗传育种实验室 作者简介: 通讯作者: 中图分类号: 基金项目: 国家"十三五"重点研发计划课题（2016YFC0503103）；中南林业科技大学研究生科技创新基金（20183002）；湖南省研究生科研创新项目（CX2018B454） Potential distribution modeling and analysis of Disanthus Maxim. Author: Affiliation: The Laboratory of Forestry Genetics,Central South University of Forestry and Technology,College of life science,Sichuan University,The Laboratory of Forestry Genetics,Central South University of Forestry and Technology,The Laboratory of Forestry Genetics,Central South University of Forestry and Technology Fund Project: 摘要 | 图/表 | 访问统计 | 参考文献 | 相似文献 | 引证文献 | 资源附件 | 文章评论 摘要:气候变化直接影响着物种的分布范围。了解气候变化对濒危物种分布区的影响，是开展保护生物学研究的基础。双花木属（Disanthus Maxim.） 1种1变种，隶属金缕梅科（Hamamelidaceae），为东亚特有濒危物种和典型的中-日间断分布成分，在研究东亚植物区系地理演化方面具有重要的科学价值。本研究基于双花木属植物19个当前居群分布点的气候变量，运用 MaxEnt模型预测双花木属植物在末次盛冰期（约22000年前）、当前（1950-2000年）和未来（2060-2080年）气候情景下的潜在分布区的结果显示，受试者工作特征曲线下的面积（AUC=0.9999±0.0001）接近于1，表明MaxEnt模型的预测准确度极高；气候变量贡献率和Jackknife检验评估的结果显示，制约双花木属植物分布的主导气候变量是最湿月降水量和最干月降水量。采用ArcGIS 10.0中的ArcToolbox空间分析工具定量分析比较双花木属的分布动态，基于生境稳定性（Nstab）、当前与其他时期分布区面积比（Na）和扩张/收缩程度（Ne）的分析结果揭示，在双花木属植物进化过程中，分布范围经历了收缩过程；未来的温室气体排放量升高程度不同，其适生区呈现不同程度（30%-65%）收缩，特别是RCP 8.5气候情景下，我国武夷山山脉的潜在分布区有可能会丧失。探讨双花木属植物对不同时期气候变化的响应，重建冰期以来该属植物地理分布的变迁历史，分析限制其潜在地理分布的主导气候变量，可为双花木属植物保育措施的制定和东亚地区植物区系物种形成演化的研究提供理论参考。 Abstract:Rapid climate change has greatly contributed to the species distribution of Disanthus. Understanding the influence of climate change on the distribution of endangered species is essential for conservation biology. Disanthus Maxim., a genus that includes one species and one variety, is endemic to East Asia. It is the most basal and the oldest genus in Hamamelidaceae, and has a discontinuous distribution across China and Japan. This genus is significant for the study of the phylogeny and the biogeography of East Asia. In this paper, nineteen populations of Disanthus Maxim. were selected to study the potential distribution of this genus during current, Last Glacial Maximum, and future periods, for which the representative concentration pathways of greenhouse gases were 2.6, 4.5, 6.0, and 8.5, respectively. A high area under the receiver operating characteristic curve (AUC=0.9999±0.0001) indicated that the prediction accuracy of the MaxEnt model was very high. The precipitation of the wettest month and precipitation of the driest month were the dominant factors affecting the distribution of this genus. Quantitative analysis performed in ArcToolbox were used to compare the distribution dynamic of the genus. An analysis based on the habitat stability of the population (Nstab), the area ratio of the distribution area between Current and other periods (Na), and the degree of expansion or contraction (Ne) showed that Disanthus Maxim. underwent contraction coupled with evolution. The suitable distribution area of Disanthus Maxim. will likely alter depending on increases in greenhouse gas emissions in the future. The potential contractions in the distribution of Disanthus Maxim. range from thirty to sixty five percent. It is likely that the Disanthus Maxim. population found in the Wuyishan Mountains would be lost under RCP 8.5, in particular. Predicting the potential distribution areas of this genus in different periods would be helpful to improve our understanding of how the genus responds to climate change and the restriction mechanisms of environmental variables on the potential distribution of the species. This study could provide a theoretical reference point for the establishment of conservation measures for Disanthus Maxim. and help the study of the formation and evolution of the flora of East Asia. 参考文献 相似文献 引证文献