Assessing the impact of land use and climate change on the evergreen broad-leaved species of <Emphasis Type="Italic">Quercus acuta</Emphasis> in Japan

To assess the impact of Quercus acuta, a dominant species in the evergreen broad-leaved forests of Japan, and its habitat shifts as a result of climate change, we predicted the potential habitats under the current climate and two climate change scenarios using a random forest (RF). The presence/absence records of Q. acuta were extracted from the Phytosociological Relevè Data Base as response variables, and four climatic variables (warmth index, WI; minimum temperature of the coldest month, TMC; summer precipitation, PRS; and winter precipitation, PRW) were used as predictor variables. The mean decrease in the Gini criterion revealed that WI was the most influential factor followed by TMC. The RF revealed a considerable increase in potential habitats (PHs) under the climate change scenarios for 2081–2100 (RCM20, 180,141 km²; MIROC, 175,635 km²) relative to the current climate (150,542 km²). The land use variables were used for masking PH. The PH masked by land use (PHLU) was approximately half of the PH under the current conditions (74,567 km²). Under the climate change scenarios and 1 km migration options, the PHLU were not increased relative to its value under the current conditions. The distribution of Q. acuta was restricted by the northward shift in northern Honshu, but expanded as a result of the upward shift into the mountain areas of Western Japan. Habitat fragmentation reduced the ability of migration to respond to climate change in the lowland areas of Japan.     

How climate,migration ability and habitat fragmentation affect the projected future distribution of European beech

Recent efforts to incorporate migration processes into species distribution models (SDMs) are allowing assessments of whether species are likely to be able to track their future climate optimum and the possible causes of failing to do so. Here, we projected the range shift of European beech over the 21st century using a process‐based SDM coupled to a phenomenological migration model accounting for population dynamics, according to two climate change scenarios and one land use change scenario. Our model predicts that the climatically suitable habitat for European beech will shift north‐eastward and upward mainly because (i) higher temperature and precipitation, at the northern range margins, will increase survival and fruit maturation success, while (ii) lower precipitations and higher winter temperature, at the southern range margins, will increase drought mortality and prevent bud dormancy breaking. Beech colonization rate of newly climatically suitable habitats in 2100 is projected to be very low (1–2% of the newly suitable habitats colonised). Unexpectedly, the projected realized contraction rate was higher than the projected potential contraction rate. As a result, the realized distribution of beech is projected to strongly contract by 2100 (by 36–61%) mainly due to a substantial increase in climate variability after 2050, which generates local extinctions, even at the core of the distribution, the frequency of which prevents beech recolonization during more favourable years. Although European beech will be able to persist in some parts of the trailing edge of its distribution, the combined effects of climate and land use changes, limited migration ability, and a slow life‐history are likely to increase its threat status in the near future.     

Modeling of habitat suitability of Asiatic black bear (Ursus thibetanus gedrosianus) in Iran in future

Future changes in climate are imminent and they threat endangered and rare species due to habitat destruction. The Asiatic black bear (Ursus thibetanus gedrosianus) is a rare and vulnerable species whose habitat fragmentation and habitat loss decreased the size of its population significantly. Climate change is another threat to this species that is investigated in this research work. Aiming at this goal, ten species distribution models (SDMs) were applied as helpful tools for evaluating the potential effectiveness of climate change in habitat suitability of Asiatic black bear in Iran. Potential dispersal of Asiatic black bear was modeled as a function of 32 environmental variables for the current time and 2070 for 44 climate change scenarios (CC scenario) of future climate. Our results showed that modeling result depended on type of model. Our results confirmed that one of the greatest threats in the near future for Asiatic black bear was the change of suitable habitat due to climate change. All the CC scenarios showed that migration of this species would be to the north and west areas with higher elevation and that an increase in area would be more than a decrease in area in all scenarios. Recognizing and protecting potential future habitats are of the important activities to conserve this species and identify areas with conservation priority.     

水菜花种群潜在生境选择与空间格局预测

国家二级保护野生植物水菜花(Ottelia cordata)，喜生于清洁的水环境中，对环境变化极为敏感，是检验湿地环境及气候变化的关键指示物种之一，在我国仅零星分布于海南北部的火山熔岩湿地区，生存状况不容乐观。研究水菜花种群潜在生境选择及其空间格局演变，有利于加强濒危物种保护保育及湿地生态系统修复、管理。该研究基于GIS平台和MaxEnt模型，结合气候、地形和土壤因子，探究水菜花种群环境限制因子及其在气候变化背景下潜在适宜生境的演变格局。结果表明，水菜花种群对温差与降水量变化敏感，等温性、最冷季度降水量、土壤类型和年均降水量对水菜花种群分布影响显著；全新世中期-当前-2070年气候变化背景下，水菜花适宜生境面积先减小后增大，分布重心呈西南-东北-西南转移格局；未来气候情景下，水菜花种群高度和中度适宜生境缩减，低适宜生境增加，南部地区将出现新增适宜生境，东北、西北及西南部适宜生境将发生消减。该研究从气候环境角度论证了水菜花种群的潜在生境选择及空间变化特征，可为濒危物种保护保育、湿地管理及其生物多样性维护工作提供参考和指导。     

气候变化情景下外来入侵植物刺苍耳在新疆的潜在分布格局模拟

明确区域尺度上外来入侵种的潜在分布格局及其对气候变化的响应对入侵种的预防和控制具有重要意义。以外来入侵植物刺苍耳(Xanthium spinosum L.)为研究对象,以其扩散蔓延的新疆地区为研究区域,结合中国国家气候中心开发的BCC—CSM1—1模式下的将来气候条件,应用MaxEnt模型和ArcGIS空间分析技术构建了未来不同气候变化情景(RCP4.5,8.5)下2050s和2070s的刺苍耳适宜生境预测模型,定量的展示了气候变化情景下刺苍耳在新疆的扩散趋势及其适宜生境的面积空间变化和分布区中心移动轨迹。结果表明:年降雨量、下层土壤有机碳含量、上层土壤pH值、年温度变化范围、降雨量的季节性变化和年平均温度是影响刺苍耳地理分布的主导环境因子;博州、塔城、阿勒泰西北部、哈密中部、巴州北部、克州中部、阿克苏北部、奎屯市、克拉玛依市、五家渠市、喀什市等地为高危入侵风险区;两种气候模式下刺苍耳的各级适生区面积和总适生面积均呈持续增加的变化趋势,且在RCP8.5情景(最高温室气体排放情景)下响应更为敏感;总体上看,刺苍耳在新疆的分布未达到饱和,呈现以塔城中部为中心,向天山北麓和塔克拉玛干北缘方向辐射状扩散,且两种气候变化情景下至2070s分布区中心均向伊犁州奎屯方向移动。     

Poor effectiveness of Natura 2000 beech forests in protecting forest-dwelling bats

With the establishment of the Natura 2000 (N2000) network, the European Union intends to develop strategies to conserve Europe's threatened habitats and species, including bats. Forest-dwelling bats are highly reliant on forest structures, such as snags and hollow trees, which the bats need as roosts. The decrease in such forest microhabitats significantly affects the habitat use and, therefore, the activity in forests. To determine whether N2000 beech forests under active timber production offer better habitats for bats compared to commercially used non-N2000 forests, we measured the bat activity and assessed the potential roosts in trees and snags in eleven pairs of stands. All survey stands represented mesotrophic beech forests (Fagus sylvatica L.) of the N2000 habitat type 9130 (Asperulo-Fagetum) in three European Biogeographic Regions. The activity of all bat species, the activity of priority N2000 species, the species number, the number of trees with roosts and the snag volume did not differ significantly between the N2000 and non-N2000 stands. We conclude that the current management of the N2000 beech forests is almost identical to that of non-N2000 commercial forests, and thus, the N2000 status has not led to an increase of bat-relevant habitat variables yet. Consequently, additional efforts beyond the administrative assignment of N2000 areas are required to build and ensure an ecologically effective and sustainable network of beech forests in Europe, including increasing important forest requirements for bats, such as roosts and snags.     

Predicting the in-between: Present and future habitat suitability of an intertidal euryhaline fish

New World mangrove trees are foundation species, and their range is predicted to expand northward with climate change. Foundation species are commonly prioritized for conservation, with the goal of preserving the entire community that depends on them. However, no studies have explicitly investigated whether mangrove-dependent species' ranges will track the northward expansion of New World mangrove forests. We use the mangrove rivulus fish, Kryptolebias marmoratus, to investigate shifts in habitat suitability in response to various climate change scenarios (Representative Concentration Pathways 2.6, 4.5, 6.0, and 8.5). Niche models for coastal species focus on traditional climatic variables (e.g., precipitation, temperature) even though coastal habitats also are directly influenced by marine variables (e.g., sea surface salinity). We employ a novel data integration method that combines marine and climatic variables, and that accounts for model selection uncertainty using model averaging to provide robust estimates of habitat suitability. Contrary to expectation, suitability of rivulus habitat is predicted to increase in the south and decrease or remain unchanged in the north across all climate change scenarios. Thus, rivulus might experience range contraction, not expansion. Habitat became more suitable with increased salinity of the saltiest month and precipitation of the driest quarter. In laboratory settings, rivulus have higher survival, reproductive success, and growth rates in low salinities. This discrepancy suggests that some combination of the responses of rivulus and its competitors to environmental change will restrict rivulus to habitats that laboratory experiments consider suboptimal. Our models suggest that focusing conservation decisions on foundation species could overestimate habitat availability and resilience of affiliated communities while simultaneously underestimating species declines and extinction risks.     

气候变化背景下紫楠在中国的适宜分布区模拟

为了解气候对紫楠(Phoebe sheareri)分布的影响,应用Maxent和GARP模型模拟了紫楠在当前气候下的中国适宜分布区,分析了影响其分布的主要环境因子,并预测了未来气候情境下其分布区的变化。结果表明,紫楠适宜分布在长江中下游及以南的各省区。影响紫楠分布的主要环境因子有年降雨量、最干季均温、降雨的季节性、相对湿度和6-8月的日照时数,这5个因子的累积贡献率达84.3%。在未来气候情境下,广东、云南、广西和海南等地区的适生区面积会显著锐减,而陕西中部、河南南部、安徽东部和江苏北部适生区面积会大幅度增加。因此,在未来气候变化背景下,紫楠的适宜分布区有向北扩张的趋势。     

Modelling potential impacts of climate change on the bioclimatic envelope of species in Britain and Ireland

Aim Climate change has the potential to have significant impacts on the distribution of species and on the composition of habitats. This paper identifies the potential changes in the future distribution of species under the UKCIP98 climate change scenarios, in order that such changes can be taken into account in conservation management. Location The model was applied to Britain and Ireland. Methods A model based on an artificial neural network was used to predict the changing bioclimate envelopes of species in Britain and Ireland. Fifty‐four species representing 15 habitats were modelled. Results The modelled species could be placed into three categories: those losing suitable climate space, those gaining it, and those showing little or no change. When the species were associated with habitats it was found that Arctic–Alpine/montane heath communities were the most sensitive to climate change, followed by pine woodland and beech woodland in southern England. In lowland heath, wet heath, cereal field margins, coastal grazing marsh, drought‐prone acid grassland and calcareous grassland, the species either showed little change or an increase in suitable climate space. The other eight habitats showed a mixed response. Conclusions The species show a variety of responses to climate change and thus their current habitat associations may alter. The uncertain future of some species and habitats is highlighted. Conservation policy and practice will need to be revised in the face of climate change.     

Potential impacts of climate change on habitat suitability of Fagus sylvatica L. forests in spain

Abstract

Fagus sylvatica forests are considered to be of Community interest according to Directive 92/43/EEC. Climate change predictions for Spain point to a warming scenario, coupled with decreasing rainfall, which may have an impact on their future distribution particularly at the extremes of its distribution area. Species distribution models incorporating bioclimatic, topographic and phytogeographic variables were used as predictors to assess their habitat suitability under current conditions and a climate change projection. Ten single models were generated and an ensemble-forecasting model was subsequently built by computing a consensus of single-model projections. The results revealed that ombrothermic indices are the main factors controlling the distribution of Spanish beech forests. They are highly vulnerable to climate change and could suffer a decline in their habitat suitability if climate trends observed are maintained in the future. The least favoured areas for them will be located close to the limit between the Temperate and Mediterranean climates, where they could suffer a loss of habitat suitability. Conversely, suitable new areas could be found mainly in western areas of the Cantabrian Range and in the Central Pyrenees.     

The Impact of Climate Change on the Potential Distribution of Agricultural Pests: The Case of the Coffee White Stem Borer (Monochamus leuconotus P.) in Zimbabwe

The production of agricultural commodities faces increased risk of pests, diseases and other stresses due to climate change and variability. This study assesses the potential distribution of agricultural pests under projected climatic scenarios using evidence from the African coffee white stem borer (CWB), Monochamus leuconotus (Pascoe) (Coleoptera: Cerambycidae), an important pest of coffee in Zimbabwe. A species distribution modeling approach utilising Boosted Regression Trees (BRT) and Generalized Linear Models (GLM) was applied on current and projected climate data obtained from the WorldClim database and occurrence data (presence and absence) collected through on-farm biological surveys in Chipinge, Chimanimani, Mutare and Mutasa districts in Zimbabwe. Results from both the BRT and GLM indicate that precipitation-related variables are more important in determining species range for the CWB than temperature related variables. The CWB has extensive potential habitats in all coffee areas with Mutasa district having the largest model average area suitable for CWB under current and projected climatic conditions. Habitat ranges for CWB will increase under future climate scenarios for Chipinge, Chimanimani and Mutare districts while it will decrease in Mutasa district. The highest percentage change in area suitable for the CWB was for Chimanimani district with a model average of 49.1% (3 906 ha) increase in CWB range by 2080. The BRT and GLM predictions gave similar predicted ranges for Chipinge, Chimanimani and Mutasa districts compared to the high variation in current and projected habitat area for CWB in Mutare district. The study concludes that suitable area for CWB will increase significantly in Zimbabwe due to climate change and there is need to develop adaptation mechanisms.     

The impact of climate change and potential distribution of the endangered white winged wood duck (Asarcornis scutulata, 1882) in Indian eastern Himalaya

The White-Winged Wood duck (Asarcornis scutulata) is an endangered forest wetland bird currently on the verge of extinction due to an array of anthropogenic pressures. It has been reported that global climate change could affect the distribution of many bird species globally. Therefore, an understanding the potential distribution of the White-Winged Wood duck in future climate scenarios could facilitate the creation of immediate conservation plans and the mitigation of subsequent threats. This is the first ever study on the distribution of White-Winged Wood Duck (WWWD) where Representative Concentration Pathway (RCP) 8.5 scenario was used to forecast the distribution of the WWWD in the Indian Eastern Himalayan region in the 2050s and 2070s. The study revealed that 1.87 % of the total area of IEH has the high potential distribution of WWWD. The state of Assam alone includes 1.68 % of the highly potential habitat in the region. It was predicted that 436.61 km² of highly potential habitat would be lost by 2070. Changes in the annual temperature range, precipitation in the wettest months (June to September), and precipitation decrease in the warmest quarter (October to December) would result in the loss of highly potential habitats. Under the influence of climate change, the habitat of WWWD in the eastern part of the region is likely to shift towards the western part. It was found that there will be a decline in potential habitat in the Indian states of Arunachal Pradesh, Assam, Nagaland, and Tripura located in the IEH under future climate scenarios. The potential of areas located at the Bhutan and Assam border would increase for supporting WWWD as this species' requires the average annual precipitation about 1000–1200 mm. However, the simultaneous anthropogenic activity would further destroy potential habitats in the future. The current study has provided baseline data on the potential distribution of WWWD in the IEH region for immediate conservation management plans.     

Potential risks for European beech (Fagus sylvatica L.) in a changing climate

Over large areas of Europe, coniferous monocultures are being transformed into mixed forests by the re-introduction of broadleaf tree species belonging to the potential natural vegetation. One important species of interest in this changing forest policy is European beech (Fagus sylvatica). However, at present, this forest management directive has ignored potential adverse effects of global climate change on wide-spread re-introduction of beech to these areas. Average global surface temperatures have risen by approx. 0.8°C in the period between 1861 and 2005 and are expected to continue to increase until the end of this century by 1.5–5.8°C above the 1990 value. To estimate the climate change in the southern part of central Europe in future, we reviewed calculations from regional climate models. Temperature increase for the southern part of central Europe is projected to be up to 2°C within the next 40 years. In contrast, the annual precipitation will most likely remain constant over the same time period, but will experience significant changes in seasonal patterns. Rising intensities of individual precipitation events may result in increasing number and intensities of flooding events and reduced precipitation during the growing season in a higher frequency of summer droughts. Growth and competitive ability of European beech will not, necessarily, respond to increasing CO₂ concentrations but may be strongly impacted by intensive drought that occurs during the growing season. Seedlings as well as adult trees may suffer from xylem embolism, restricted nutrient uptake capacity and reduced growth under limited water availability. However, it remains uncertain to what extent other environmental factors (e.g. soil properties, competitive interactions) may modify the drought response of beech, thus either enhancing susceptibility or increasing drought tolerance and resilience potential. Water-logged soils, predicted during the spring for several regions due to higher than average precipitation, could negatively impact nutrient uptake and growth of beech. Whereas other dominant species as, e.g. oak are well adapted to that environmental stress, beech is known to be sensitive to water-logging and flooding. Thus, the competitive capacity of beech might—depending on the other environmental conditions—be reduced under the expected future climate conditions. Silvicultural practices must be aware today of the potential risks which a changing climate may impose on sustainable forest development.     

Effects of climatic change on the distribution and conservation of Mediterranean forests: the case of <Emphasis Type="Italic">Tetraclinis articulata</Emphasis> in the Iberian Peninsula

South-eastern Spain is a key area for assessing the effects of climatic change on Mediterranean biodiversity since it represents an ecotone between the Mediterranean macrobioclimate and a vegetation with subtropical components. It also maintains many restricted-distribution species such as forests of Tetraclinis articulata, which with the exception of Malta, only is found here in Europe. The likely response of the species under B2 and A2 climatic scenarios is studied, using the species distribution model (SDM) and a high-resolution regional climate model (RCM). The results point to a marked increase in potential habitat under the B2 scenario, including a shift toward higher altitude and latitude values. Under the A2 scenario a substantial reduction in potential habitat is to be expected, accompanied by a drastic change in its geographical distribution, with the emergence of a new suitable area in the mountains of the interior and the total loss of the species’ present coastal habitat. Under the B2 scenario the network of reserves seems to be adequate since this would provide a substantial increase in the protected habitat, the present and future potential habitats partially overlap and most of the reserves are sufficiently close to allow the migration of the species by means of short-distance dispersal mechanisms. Under the A2 scenario, two existing reserves in the interior would be suitable, although the probability of natural migration is low due to the low dispersal capability of the species and the absence of overlapping areas between the present and future potential distribution areas.     

未来气候变化对不同国家茶适宜分布区的影响

茶是对气候变化敏感的重要经济作物, 评价全球气候变化对茶分布和生产的影响对相关国家经济发展和茶农的生计至关重要。本研究基于全球858个茶分布点和6个气候因子数据, 利用物种分布模型预测全球茶的潜在适宜分布区及其在2070年的不同温室气体排放情景(RCP2.6和RCP8.5)下的变化。结果表明: 当前茶在五大洲均有适宜分布区, 主要集中在亚洲、非洲和南美洲, 并且最冷季平均温和最暖季降水量主导了茶的分布。预计2070年, 茶的适宜分布区变化在不同的大洲、国家和气候情景间将存在差异。具体来说, 茶的适宜分布区总面积将会减少, 减少的区域主要位于低纬度地区, 而中高纬度地区的适宜分布区将扩张, 由此可能导致茶的适宜分布区向北移动; 重要的产茶国中, 阿根廷、缅甸、越南等茶适宜分布区面积会减少57.8%-95.8%, 而中国和日本的适宜分布面积则会增加2.7%-31.5%。未来全球新增的适宜分布区中, 约有68%的地区土地覆盖类型为自然植被, 因此可能导致新茶树种植园的开垦和自然植被及生物多样性保护产生冲突。     

Current and future habitat availability for Thick‐billed and Maroon‐fronted parrots in northern Mexican forests

Thick‐billed Parrots (Rhynchopsitta pachyrhyncha) and Maroon‐fronted Parrots (Rhynchopsitta terrisi) are the only parrots in Mexico found in high‐elevation coniferous forests. Both species are critically endangered due to logging, and climate change is expected to further reduce their available habitat. Our objectives were to assess the present and future availability of a suitable habitat for these parrots using ecological niche models. Future climatic scenarios were estimated by overlaying the present distributions of these parrots on maps of projected biome distributions generated using a North American vegetation model. Our climatic scenarios revealed that the distribution of key habitats for both parrots will likely be affected as the climate becomes more suitable for xeric biomes. The climate associated with coniferous forests in the current range of Maroon‐fronted Parrots is predicted to disappear by 2090, and the climate associated with the key coniferous habitats of Thick‐billed Parrots may contract. However, our results also indicate that suitable climatic conditions will prevail for the high‐elevation coniferous biomes where Thick‐billed Parrots nest. The degree to which both species of parrots will be able to adapt to the new scenarios is uncertain. Some of their life history traits may allow them to respond with a combination of adaptive and spatial responses to climatic change and, in addition, suitable climatic conditions will prevail in some portions of their ranges. Actions needed to ensure the conservation of these parrots include strict control of logging and integration of rapid response teams for fire management within the potential foraging ranges of nesting pairs. A landscape with a greater proportion of restored forests would also aid in the recovery of current populations of Thick‐billed and Maroon‐fronted parrots and facilitate their responses to climate change.     

Climate change may plunder the facultative top predator Yellow-throated Martin from the Hindu-Kush Himalayan Region

The mountain ecosystems are fragile because of topography and extreme climatic conditions. The Hindu-Kush Himalayan (HKH) region is a biodiversity-rich ecosystem and highly vulnerable to climate change and anthropogenic activities among the mountains. In HKH, the climate change impacts on ecologically specialist species are already evident, but generalist species are not much studied. One such generalist species distributed throughout the HKH is Yellow-Throated Marten (YTM) (Martes flavigula Boddaert, 1785), a facultative predator that occupies the Southern flank of the HKH. The YTM is one of the least studied animals distributed up to 4510-m elevation. The HKH covers 61 terrestrial ecoregions and 304 Protected Areas (PAs). An ecologically successful facultative predator of the region is seriously threatened because of habitat loss and climate change. Hence, we used an ensemble model to map the distribution of suitable habitats and their representativeness in terms of ecoregions and PA coverage. The results indicated that by 2050, the distribution range might decline to 58.78% and 49.33% with reference to the current scenario under the representative concentration pathway (RCP) 4.5 and 8.5 scenarios, respectively. The species may lose much of its range, mainly in the eastern part of the HKH landscape. Furthermore, the centroid of the distribution may also shift to the northwest, thereby abandoning many areas and occupying new refugia. The Upper Gangetic plains moist deciduous forests ecoregion possess the highest suitable habitats for the YTM, with a mean value of 0.744. At the same time, the existing PA network represents only 12.2% of its suitable habitat in HKH. Hence, for the long-term viability of the species, there is a need to enhance protection and improve habitat quality.     

The impact of climate change on the future geographical distribution range of the endemic relict tree Gleditsia caspica (Fabaceae) in Hyrcanian forests

The Caspian locust (Gleditsia caspica) is an endemic relict tree that occurs in Hyrcanian forests. Many of its habitats have been destroyed in the last half-century. This study was performed to map past geographic distributions and estimate the suitable areas and potential risks of remaining populations under future climate change. Eight bioclimatic scenarios (one with current conditions, three with future climates, and four with past conditions) were tested using the maximum entropy algorithm. The most significant factors influencing the distributions of G. caspica were precipitation in the driest month and temperature seasonality. Even under the most optimistic model (RCP2.6), many stands of G. caspica may become endangered in the eastern and central parts of the range, and the distribution of this species will probably shift to the west of the Hyrcanian forest area. Considering the increasing destruction of habitats of this species due to human activities and the expected negative effects of climate change in the future, it is recommended that nature reserves be established to protect the habitat of G. caspica. Additionally, ex situ conservation strategies, such as storing seeds using cryopreservation techniques, can ensure the long-term survival of this species in the future.     

基于MaxEnt模型不同气候变化情景下的豆梨潜在地理分布

针对豆梨的原生境保护和资源利用问题,本研究基于豆梨全球236个分布点和19个环境因子,利用最大熵模型(MaxEnt)和地理信息系统(GIS)预测了豆梨在不同气候条件下的全球生态适宜区.结果表明: 豆梨的生态适宜区主要集中在北美洲、亚洲等地区,面积共约1.6×10⁷ km².其中,中国生态适宜度较高的地区主要分布在湖南省、湖北省、安徽省、江西省、江苏省、浙江省、福建省等地.影响豆梨地理分布的主要气候因子是年平均气温和年降水量,气温季节性变化次之.由模型预测可知,在不同的气候背景下,豆梨适宜生境和低适宜生境的面积有所不同.在空间分布上,豆梨适宜生境和低适宜生境的范围和几何中心都由东部向西部地区扩散,北美洲的适宜生境增长较快,而欧洲地区的低适宜生境增长较快.     

Predicting the distributions of Pouteria adolfi-friederici and Prunus africana tree species under current and future climate change scenarios in Ethiopia

Distributions of potential ranges of plant species are not yet fully known in Ethiopia where high climatic variability and vegetation types are found. This study was undertaken to predict distributions of suitable habitats of Pouteria adolfi-friederici and Prunus africana under current and two future climate scenarios (RCP 4.5 and RCP 8.5 in 2050 and 2070) in Ethiopia. Eleven environmental variables with less correlation coefficients (r < 0.7) were used to make the prediction. Shifting in extents of habitat suitability and effects of elevation, solar radiation and topographic position in relation to the current and future climatic scenarios were statistically analysed using independent t-test and linear model. We found decreasing area of highly suitable habitat from 0.51% to 0.46%, 0.36% and 0.33%, 0.24% for Prunus africana and 1.13% to 1.02%, 0.77% and 0.76%, 0.60% for Pouteria adolfi-friederici, under RCP 4.5 and RCP 8.5 by 2050 and 2070 respectively. Moist and dry afromontane forests are identified as the most suitable habitat for both species. Overall, our results suggest that climate change can promote dynamic suitable habitat niches under different future climate scenarios. Therefore, biodiversity conservation strategies should take into account habitat suitability dynamics issues and identify where to conserve species before implementing conservation practices.