共查询到19条相似文献，搜索用时 421 毫秒
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基于云南沙棘在中国的78个种群分布点位数据与22个地理环境变量，利用MaxEnt模型模拟了云南沙棘在当前气候与未来(2050S、2070S)3种不同气候情景(RCP2.6、RCP4.5和RCP8.5)的潜在地理分布，探讨影响云南沙棘分布的主导环境变量，揭示未来气候变化下云南沙棘的变化趋势。结果表明：(1)影响云南沙棘生长的主要环境变量为热量(温度季节性变动系数、等温性、最冷季平均温度)、地形(海拔、坡度)和水文(年降水量),其中海拔、年降水量及温度季节性变动系数对其影响极其显著，累计贡献率为60%;(2)当前气候情景下，云南沙棘的高适宜生境与适宜生境面积分别为5.88×104km2和23.97×104km2,分别占中国国土面积的0.61%与2.49%,适宜种植生境集中分布在我国横断山脉地区；(3)2041—2060年间3种不同气候情景下云南沙棘适宜生境和高适宜生境面积为增长趋势，在2061—2080年间RCP8.5情景下云南沙棘的高适宜生境为减小趋势，适宜生境呈现增加趋势。云南沙棘适宜生境有向西南方... 相似文献
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【目的】以我国特有的同倍体杂交树种紫果云杉为对象,研究其与亲本树种丽江云杉和青杄间环境生态位的差异,并预测其在未来气候变化下21世纪50年代(2050s)和80年代(2080s)潜在分布区的变化。【方法】在收集紫果云杉及其亲本种地理分布信息的基础上,利用地理信息系统(Arc GIS)技术获取相应生境的环境变量,通过Kruskal-Wallis多重秩和检验、判别式分析(DFA)和主成分分析(PCA)等统计方法量化分析云杉属3个树种的生态位差异,并利用最大熵模型(Max Ent)结合3种大气环流模型(BCC-CSM1-1、CCCma_Can ESM2和CSIROMk3.6.0)模拟3个树种在3种气候变化情景(即温室气体最低排放,RCP2.6;中度稳定排放,RCP4.5;高度排放,RCP 8.5)下未来2050s和2080s的潜在分布。【结果】Kruskal-Wallis检验、DFA和PCA结果均表明紫果云杉生境的水热条件与亲本种间均存在显著差异。对水分条件而言,尽管紫果云杉生境的最冷季与最暖季降雨量居于亲本种之间,但其生境土壤湿度显著高于2个亲本种;对热量条件而言,紫果云杉生境的最冷月最低温显著低于2个亲本种,且地面结霜频率显著高于亲本。进一步对云杉属3个树种的未来潜在分布区模拟显示,紫果云杉仅在RCP2.6下2080s的潜在分布面积与当前相比略有缩减(约5%),而在此情景下2050s的潜在分布区面积和其余2个情景下2050s和2080s的潜在分布面积高于当前分布区面积。综合分析所有情景及时间段后发现,紫果云杉未来潜在分布区面积平均增加17%以上,且分布区明显呈现由青藏高原东南部边缘向内部扩张的趋势。而其亲本种青杄受气候变暖威胁严重,其潜在分布面积(综合所有情景及时间段)平均减少了21%以上,丽江云杉除在RCP4.5和RCP8.5下2080s的潜在分布面积稍高于当前(不到2%)外,其余情景下的潜在分布面积也都低于当前,其潜在分布面积平均减少5%左右(综合所有情景及时间段)。【结论】明确了同倍体杂交物种紫果云杉与其亲本种生态位的环境差异,即高土壤湿度和冬季低温是紫果云杉与其亲本种产生生态位分化的主要因子;且在未来温度显著增加背景下,基于MaxEnt模型预测表明紫果云杉在未来2050s和2080s潜在分布区面积将显著增加,推测其在未来将发挥更重要的生态安全屏障作用。 相似文献
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为确定北沙柳在我国的适生情况,本研究将北沙柳地理分布信息与6个气候因子基于最大熵模型(MaxEnt)对其潜在分布进行模拟预测。AUC值大于0.9,表明预测结果良好;影响北沙柳分布主导环境因子有年平均温度、温度季节变化、海拔、最湿月降水量、昼夜温差与年温差比值、最干月降水量、昼夜温差月均值;计算出北沙柳在我国的存在概率,DIVA-GIS自动划分为4个等级,分别为不适应生境(p0.07)、低度适应生境(0.07≤p0.24)、中度适应生境(0.24≤p0.49)、高度适应生境(0.49≤p0.95);当前时期到未来(2050年)时期4个情景(RCP 2.6、RCP 4.5、RCP 6.0、RCP 8.5)下的适生区面积均有所增加。模型预测结果显示,北沙柳适生区主要集中在鄂尔多斯市和榆林市交汇处、中卫市与阿拉善左旗交汇处。结合北沙柳的实际地理分布信息与基于MaxEnt模型预测的当前时期的潜在分布基本吻合,表明MaxEnt模型对北沙柳的潜在生境概率预测可靠,得出的结果对北沙柳的推广与引种具有一定参考价值。 相似文献
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《林业科学》2021,57(10)
【目的】预测现在和未来气候情景下我国特有濒危动物褐马鸡潜在生境分布的变化,为制定有关保护政策提供科学依据。【方法】基于褐马鸡152个分布点和26个环境变量数据,利用MaxEnt模型模拟褐马鸡在我国的潜在地理分布,并基于该模型预测国际政府间气候变化专门委员会(IPCC)发布的RCP4.5和RCP8.5气候情景下21世纪50和70年代褐马鸡潜在分布范围。【结果】所有训练集与验证集为AUC均大于0.8,所构建模型的预测准确性达到优良标准。当前褐马鸡潜在分布生境的主要影响因子(贡献率)依次为年降水量(15.4%)、昼夜温差月均值(15.3%)、植被类型(9.7%)、最干季降水量(9.1%)、最湿季降水量(8.7%)、到道路距离(8.2%)和到水源距离(7.8%)等,累计贡献率达74.2%,且各因子阈值分别为525～580 mm、8.2～10.8℃、植被类型偏向于阔叶林和针阔混交林、12.4～17.1 mm、310～340 mm、0～2.5 km,0～0.63 km和大于10 km。褐马鸡的适宜生境主要分布在陕西黄龙山、山西吕梁山、河北小五台山和北京百花山,其适宜、中度适宜和不适宜区面积占研究区面积比例分别为6.45%、19.92%和73.62%。与当前情景下相比,未来褐马鸡可生存生境表现为增加趋势,且适宜和中度适宜生境变化趋势相同,而21世纪50和70年代之间几乎不变。【结论】褐马鸡适宜生境主要分布在陕西黄龙山、山西吕梁山、河北小五台山和北京百花山,未来可生存生境表现为增加趋势。影响褐马鸡分布的主要因子为年降水量、昼夜温差月均值、植被类型、最干季降水量、最湿季降水量、到道路距离和到水源距离等。建议对褐马鸡适宜区加强重点保护,对中度适宜区加强保护和管理,同时也要加强常绿针叶林木的栽植和人口控制。 相似文献
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滇西北滇金丝猴栖息地景观格局分析及其破碎化评价 总被引：1，自引：0，他引：1
生境丧失及破碎化已成为生物多样性最主要的威胁之一,对物种栖息地的景观格局进行分析及对其破碎化进行评价显得十分必要.对滇金丝猴栖息地景观格局和破碎化进行分析评价,结果表明,包括滇金丝猴适宜生境在内的森林面积占整个研究区面积的2/3,是该地区的主导景观类型;研究区景观格局已表现出一定程度的景观破碎化.滇金丝猴适宜生境面积为308 212.44 hm2,占整个研究区面积的18.86%.目前滇金丝猴适宜生境的破碎化程度较低,但仍需控制适宜生境已出现的景观破碎化,并通过生境恢复及廊道重建等措施加强对滇金丝猴的保护. 相似文献
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基于MaxEnt模型的松针红斑病在中国的潜在分布区及适生性预测分析 总被引：1，自引：0，他引：1
【目的】依据气候变化,探究气候变化对松针红斑病分布的影响,预测中国松针红斑病的潜在分布区。【方法】根据松针红斑病已知分布区域和相关气候数据,结合政府间气候变化专门委员会(IPCC)针对未来气候变化情景发布的CCSM4气候模式数据,采用最大熵模型(MaxEnt)预测松针红斑病的潜在分布区。【结果】松针红斑病最适宜分布区为黑龙江、吉林、辽宁、内蒙古东北部和云南省。经刀切法分析(Jackknife)表明,6月降水量、11月平均最高温度和最冷季度降水量等主要影响松针红斑病的潜在分布区。在未来不同气候变化情景下,总适宜区面积呈上升趋势,增加幅度为15. 66%～18. 29%。山东北部、河北、山西的大部分地区、陕西中部和南部、甘肃东南部、四川北部和南部、辽宁西部和内蒙古东部的各等级适宜区面积增加,适宜等级上升。【结论】MaxEnt模型预测结果与实际调查结果具有很高的一致性,能够反映松针红斑病在中国的分布情况。随着未来气候变化,云南、四川交界地区,东北三省和内蒙古东北部最适宜分布区呈现破碎化的趋势。松针红斑病适生区质心有由东北向华北、西北扩散的趋势。 相似文献
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气候变化情景下河北省3个优势树种适宜分布区预测 总被引：2，自引：0，他引：2
【目的】探究河北省3个优势树种分布与气候因子的关系,并进行适宜分布区预测,以期为评估气候变化的影响及制定适宜未来气候变化的森林经营策略提供理论依据。【方法】依据河北省森林资源调查数据,选取华北落叶松、蒙古栎和油松这3个主要树种,采用ClimateAP气候模型生成当前及未来(2040—2069年和2070—2099年)与降水和温度相关的10个气候因子,利用MaxEnt生态位模型和基于3个气候变化情景(温室气体最低排放,RCP2.6;中度稳定排放,RCP4.5;高度排放,RCP8.5)的一致性预测,模拟3个树种当前和未来的潜在适宜分布区,并采取响应曲线分析主要气候因子对3个树种适宜分布区的影响。【结果】3个树种MaxEnt模型的受试者工作特征曲线下面积(AUC值)都大于0.85,具有较好的预测能力;当前3个树种主要适宜分布在燕山和太行山地区;影响3个树种分布的主导气候因子存在差异,华北落叶松主要受小于0℃年积温和湿季降水量的影响,蒙古栎则主要受最热月平均气温、Hargreaves水分亏缺和湿季降水量的影响,而最热月平均气温、湿季降水量、大于5℃年积温和年均气温是影响油松分布的主要气候因子;一致性预测表明,在2040—2069年,河北省华北落叶松分布面积明显扩大,蒙古栎分布面积变化较小,而油松分布面积显著缩小;在2070—2099年,3个树种的适宜分布面积都显著缩小,幅度均超过3%。【结论】随着气候变化,3个树种均有向高海拔地区迁移的趋势,但在经纬度方向上的分布变化不大。在未来3个树种的适宜分布区,采取人工手段(如造林)辅助树种扩散以适应气候变化,有利于提高森林生产力,构建健康稳定的森林生态系统。 相似文献
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[目的]对澳洲坚果在中国的潜在分布区进行预测,并对其适生区进行分析和划分。[方法]通过收集澳洲坚果的地理信息数据,利用最大熵模型(MaxEnt)与地理信息系统(ArcGIS),综合相关19项气候因子,预测划定澳洲坚果在世界以及我国的潜在地理分布区。[结果]该物种生长区域狭窄,对环境要求苛刻。世界范围内,澳洲坚果的较适宜生长区在澳洲东部、南美洲东南部和马达加斯加岛东部以及亚洲地区23°26'~30°N,73°~122°E范围内。在我国,澳洲坚果适宜分布区主要集中在西藏、台湾、广西、广东和云南等地,其高适宜区面积依次为西藏(15 359km~2),台湾(14 054 km~2),广西(7 372 km~2),广东(6 147 km~2)和云南(3 776 km~2)。刀切法(Jackknife)分析显示,澳洲坚果分布主要受到极端最高温、年均气温变化范围、最干月降雨量、温度季节性变化和等温性等气象因子的影响。[结论]本研究用MaxEnt模拟澳洲坚果的潜在地理分布有一定的准确性,划分出了澳洲坚果基本的地理分布格局和潜在分布区域,并阐明了主导其地理分布的生物气候因子,为澳洲坚果尤其是在我国的引种和推广应用提供了参考。 相似文献
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【目的】基于对刺槐叶瘿蚊在全国的普查情况,利用最大熵模型MaxEnt软件的互补双对数输出方式对刺槐叶瘿蚊在中国当前和未来(2050年)的适生区进行预测,为林业和海关检疫部门对刺槐叶瘿蚊当前与未来的防控与检疫工作提供重要参考依据。【方法】使用MaxEnt、ArcGIS、R软件对刺槐叶瘿蚊危害点,气候图层,模型参数这3方面进行科学的优化选择,确保模型的科学性、有效性。当前气候适生区的预测使用WorldClim网站全球气候数据Version 1.4,未来数据则采用通用气候系统模型CCSM4下3种外排情景(RCP26、RCP45、RCP85)。【结果】最终确定52个危害点,7个主导气候图层,运用互补双对数输出方式对适生区进行预测。模拟结果的测试遗漏率与理论遗漏率基本吻合,ROC曲线即AUC值为0.919,标准差为0.023,表明所使用的数据无空间自相关,构建的模型达到"极好"的标准。通过刀切图分析,对刺槐叶瘿蚊分布影响最大的3个气候图层分别为Bio1(年平均气温)、Bio12(年降水量)、Bio5(最热月的最高温度)。对当前气候刺槐叶瘿蚊适生区进行划分,刺槐叶瘿蚊在中国的适生范围为22.08°—48.42°N,39.39°—135.06°E,达国土面积的31.90%。除西藏、青海、海南、台湾4省区外,其余省份均包含其适生区,其高度适生区以西南(四川、重庆)和华北(北京、天津、河北、山东、陕西)为主。对未来(2050年)适生区的预测,3种外排情景RCP26、RCP45、RCP85的总适生区均比当前气候的总适生范围大,以高度、中度适生区面积的增大为主,新疆和我国北部区域面积显著扩增。RCP85情景下的刺槐叶瘿蚊适生区面积最大,达国土面积的39.71%,比当前预测的多出75万km~2。【结论】结合实际调查情况,新型MaxEnt模型预测结果可信度高,阐明影响刺槐叶瘿蚊分布的主导气候因子,预测出刺槐叶瘿蚊当前与未来的分布范围及适生程度情况,对刺槐叶瘿蚊的防控具有重要意义。 相似文献
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[目的]了解环境因子对毛红椿适生区分布的影响,为其资源保护、引种及其人工林的发展提供参考。[方法]基于MaxEnt模型能利用现存不完整、小样本、离散型分布数据构建物种适生区预测模型,用受试者工作曲线线下面积(AUC)检验预测模型的精度,面积越大精度越高等优点,本研究应用毛红椿在云南的分布数据及1个地型因子和6个气候因子,来构建其适生区分布模型。[结果]毛红椿适生区分布MaxEnt模型平均训练AUC和平均测试AUC分别为0.891、0.885,说明对毛红椿适生区的预测是可靠的;降水量变异系数和最干季度降水量是决定毛红椿适生区分布的主要因子,年均气温变化范围、最冷季度平均气温、最湿季度降水量、最冷季度降水量是次要因子。在当代和未来(2050S、2070S)气候变暖条件下(RCP2.6情景),云南省和全国适生区面积计算结果直观、定量的反应了全球变暖对毛红椿适生区变迁的影响。[结论]预测云南省及全国的毛红椿适生区随全球变暖而小幅萎缩。 相似文献
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Kamrul Islam Md. Farhadur Rahman Kazi Nazrul Islam Tapan Kumar Nath Mohammed Jashimuddin 《Journal of Sustainable Forestry》2020,39(3):221-241
ABSTRACTClimate change affects plant phenology, spatial distribution, and even extinction of vulnerable species. Dipterocarpus turbinatus, locally known as garjan, is a valuable but vulnerable native tree species of Bangladesh whose spatial distribution under future climate change scenarios is not fully understood. The aim of this study was to examine the effects of present and future climatic scenarios on spatiotemporal distribution of D. turbinatus. We used maximum entropy species distribution modeling to perform the present and future habitat suitability of garjan under different climate scenarios. The representative concentration pathways (RCP) 2.6 and 8.5 were considered for bioclimatic variables from the Global Climate Model – Hadley Global Environment Model 2 Atmosphere-Ocean. The predictive accuracy of the model was more than 97% in both the training and test data. The prediction results suggest that compared to present areas (7624 km2) under moderate habitat class it will be 2755 km2 and 1239 km2, respectively, in 2050 and 2070 under RCP2.6 scenario and decreases more rapidly under RCP8.5 scenario. Besides, the prediction also indicates that the habitat of the species will shift toward the high altitudinal south-eastern corner of the country whereas local extinction might occur in the north-eastern part during 2070. 相似文献
13.
流苏香竹（Chimonocalamus fimbriatus）是云南特有珍稀竹种，主要分布于云南西南部。文章以野外调查获取的流苏香竹分布信息为主，运用最大熵模型（MaxEnt）同时结合地理信息系统（ArcGIS），基于19个气候因子，预测其在当前及未来气候变化情景下的潜在分布区。结果表明：当前流苏香竹的高适生区和中适生区主要分布于德宏州、保山市和临沧市等地，除迪庆州、丽江市和昭通市外，云南其他区域均有低适生区零星分布。在未来2050s和2070s的2个时间段，基于2种不同共享社会经济路径（SSP1-2.6和SSP5-8.5），流苏香竹的高适生区面积呈减少的趋势，尤其是SSP5-8.5路径下，高适生区面积仅为当前的12.51%（2050s）和18.63%（2070s）；中、低适生区在SSP1-2.6路径下，显著扩张（2050s）或略微扩张（2070s），在SSP5-8.5路径下，则大幅收缩。流苏香竹野外实际分布区及其潜在分布区均以斑块状为主，可能与云南特殊的地形、地貌有关。影响流苏香竹分布的主导气候因子为最湿月份降水量、最暖月份最高温度、最干季度降水量和平均气温日较差。流苏香竹对气候变化比较敏感，根据其野外分布状况，建议以就地保护为主、迁地保护为辅，在其潜在适生区内适当引种栽培。 相似文献
14.
Paul H. Evangelista Sunil KumarThomas J. Stohlgren Nicholas E. Young 《Forest Ecology and Management》2011,262(3):307-316
The aim of our study was to estimate forest vulnerability and potential distribution of three bark beetles (Curculionidae: Scolytinae) under current and projected climate conditions for 2020 and 2050. Our study focused on the mountain pine beetle (Dendroctonus ponderosae), western pine beetle (Dendroctonus brevicomis), and pine engraver (Ipspini). This study was conducted across eight states in the Interior West of the US covering approximately 2.2 million km2 and encompassing about 95% of the Rocky Mountains in the contiguous US. Our analyses relied on aerial surveys of bark beetle outbreaks that occurred between 1991 and 2008. Occurrence points for each species were generated within polygons created from the aerial surveys. Current and projected climate scenarios were acquired from the WorldClim database and represented by 19 bioclimatic variables. We used Maxent modeling technique fit with occurrence points and current climate data to model potential beetle distributions and forest vulnerability. Three available climate models, each having two emission scenarios, were modeled independently and results averaged to produce two predictions for 2020 and two predictions for 2050 for each analysis. Environmental parameters defined by current climate models were then used to predict conditions under future climate scenarios, and changes in different species’ ranges were calculated. Our results suggested that the potential distribution for bark beetles under current climate conditions is extensive, which coincides with infestation trends observed in the last decade. Our results predicted that suitable habitats for the mountain pine beetle and pine engraver beetle will stabilize or decrease under future climate conditions, while habitat for the western pine beetle will continue to increase over time. The greatest increase in habitat area was for the western pine beetle, where one climate model predicted a 27% increase by 2050. In contrast, the predicted habitat of the mountain pine beetle from another climate model suggested a decrease in habitat areas as great as 46% by 2050. Generally, 2020 and 2050 models that tested the three climate scenarios independently had similar trends, though one climate scenario for the western pine beetle produced contrasting results. Ranges for all three species of bark beetles shifted considerably geographically suggesting that some host species may become more vulnerable to beetle attack in the future, while others may have a reduced risk over time. 相似文献
15.
Haftu Abrha Emiru Birhane Haftom Hagos Ashenafi Manaye 《Journal of Sustainable Forestry》2018,37(8):842-853
Juniperus procera is the most preferred tree in Ethiopia. It is an endangered tree species enumerated in IUCN red list. Accordingly, this study investigates the future suitable habitat of the J. procera under climate change in northern Ethiopia. Three occurrence districts were visited and 124 presence observations were taken. The records, altitude, and 19 bio-climatic variables were used to run a species distribution model to account for the climate change effect on the species. Maxent, Diva-GIS, and ArcGIS were used to evaluate the outputs. Future suitable habitats were projected into mid and end-century time frames with two Representative Concentration Pathways (RCP2.6 and 8.5) under one General Circulation Model, namely the Climate Community System Model Version-4. Our results showed that minimum temperature of the coldest month and altitude are main predictors of the distribution of the species. Suitable habitats of the species will be decreased by 79.84%, 91.17%, 75.31%, and 96.25% in Mid-century RCP2.6, Mid-century RCP8.5, End-century RCP2.6, and End-century RCP8.5 when compared with current distributions, respectively. This indicates that climate change will affect the future distribution of the species. The results of the study indicate that appropriate management strategies must be taken to ensure the long-term survival of J. procera. 相似文献
16.
树流感即栎树猝死病（SOD）自从在美国发现以来,已经造成了美国加利福尼亚州树木大量死亡,并且扩散到了俄勒冈州。对树流感未来暴发风险区域的研究能够为树流感防控提供科学依据,同时为中国防治类似森林病虫害提供借鉴。联合国气候变化政府间专门委员会（IPCC）在第5次评估报告中指出,根据温室气体排放模式的不同未来气候变化有4种可能趋势。该研究基于现在的全球植被覆盖数据、过去的气候数据和未来4种不同排放模式下的气候数据,运用Maxent模型预测了北美西海岸地区在2000年、2050年、2070年树流感暴发风险区域。对预测结果的时空对比分析发现,北美西海岸地区未来树流感暴发高风险区域将会往北和西海岸地区扩张,在各种气候模式下扩张的情况不一样,其中相对于2000年,在RCP85排放模式下2070年北美西海岸地区的高风险区域将会增加174%。 相似文献
17.
Estimating potential habitat for 134 eastern US tree species under six climate scenarios 总被引：3，自引：0，他引：3
Louis R. Iverson Anantha M. PrasadStephen N. Matthews Matthew Peters 《Forest Ecology and Management》2008
We modeled and mapped, using the predictive data mining tool Random Forests, 134 tree species from the eastern United States for potential response to several scenarios of climate change. Each species was modeled individually to show current and potential future habitats according to two emission scenarios (high emissions on current trajectory and reasonable conservation of energy implemented) and three climate models: the Parallel Climate Model, the Hadley CM3 model, and the Geophysical Fluid Dynamics Laboratory model. Since we model potential suitable habitats of species, our results should not be interpreted as actual changes in ranges of the species. We also evaluated both emission scenarios under an “average” future climate from all three models. Climate change could have large impacts on suitable habitat for tree species in the eastern United States, especially under a high emissions trajectory. Of the 134 species, approximately 66 species would gain and 54 species would lose at least 10% of their suitable habitat under climate change. A lower emission pathway would result in lower numbers of both losers and gainers. When the mean centers, i.e. center of gravity, of current and potential future habitat are evaluated, most of the species habitat moves generally northeast, up to 800 km in the hottest scenario and highest emissions trajectory. The models suggest a retreat of the spruce-fir zone and an advance of the southern oaks and pines. In any case, our results show that species will have a lot less pressure to move their suitable habitats if we follow the path of lower emissions of greenhouse gases. The information contained in this paper, and much more, is detailed on our website: http://www.nrs.fs.fed.us/atlas. 相似文献
18.
This study evaluates the multifactorial spatial modelling used to assess vulnerability of the Du¨ zlerc?am?(Antalya) forest ecosystem to climate change.This was done to produce data,to develop tools to support decisionmaking and the management of vulnerable Mediterranean forest ecosystems affected by climate change,and to increase the ability of these forest ecosystems to adapt to global change.Based on regionally averaged future climate assessments and projected climate indicators,both the study site and the western Mediterranean sub-region of Turkey will probably become associated with a drier,hotter,more continental and more water-deficient climate.This analysis holds true for all future scenarios,with the exception of RCP4.5 for the period from 2015 to 2030.However,the present dry-sub humid climate dominating this sub-region and the study area shows a potential for change towards more dry climatology and for it to become semiarid between 2031 and 2050 according to the RCP8.5 high emission scenario.All the observed and estimated results and assessments summarized in this study show clearly that the densest forest ecosystem in the southern part of the study site,characterized by mainly Mediterranean coniferous and some mixed forest and maquis vegetation,will very likely be influenced by medium and high degrees of vulnerability to future environmental degradation,climate change and variability. 相似文献
19.
Daxing'anling is a key region for forest fire prevention in China.Assessing changes in fire risk in the future under multiple climatic scenarios will contribute to our understanding of the influences of climate change for the region and provide a reference for applying adaptive measures for fire management.This study analyzed the changes in fire weather indices and the fire season under four climate scenarios(RCP2.6,RCP4.5,RCP6.0,RCP8.5)for 2021–2050 using data from five global climate models together with observation data.The results showed that the analog data could project the average state of the climate for a given period but were not effective for simulating extreme weather conditions.Compared with the baseline period(1971–2000),the period 2021–2050 was predicted to have an increase in average temperature of 2.02–2.65 °C and in annual precipitation 25.4–40.3 mm,while the fire weather index(FWI) was predicted to increase by6.2–11.2% and seasonal severity rating(SSR) by5.5–17.2%.The DMC(Duff moisture code),ISI(initial spread index),BUI(build-up index),FWI and SSR were predicted to increase significantly under scenarios RCP4.5,RCP6.0,and RCP8.5.Furthermore,days with high or higher fire danger rating were predicted to be prolonged by 3–6 days,with the change in the southern region being greater under scenarios RCP4.5,RCP6.0,and RCP8.5. 相似文献