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Keliang Zhang Huina Liu Haolei Pan Wenhao Shi Yi Zhao Silei Li Junchi Liu Jun Tao 《Ecology and evolution》2020,10(11):4828-4837
Climate change poses a serious threat to biodiversity. Predicting the effects of climate change on the distribution of a species' habitat can help humans address the potential threats which may change the scope and distribution of species. Pterocarya stenoptera is a common fast‐growing tree species often used in the ecological restoration of riverbanks and alpine forests in central and eastern China. Until now, the characteristics of the distribution of this species' habitat are poorly known as are the environmental factors that influence its preferred habitat. In the present study, the Maximum Entropy Modeling (Maxent) algorithm and the Genetic Algorithm for Ruleset Production (GARP) were used to establish the models for the potential distribution of this species by selecting 236 sites with known occurrences and 14 environmental variables. The results indicate that both models have good predictive power. Minimum temperature of coldest month (Bio6), mean temperature of warmest quarter (Bio10), annual precipitation (Bio12), and precipitation of driest month (Bio14) were important environmental variables influencing the prediction of the Maxent model. According to the models, the temperate and subtropical regions of eastern China had high environmental suitability for this species, where the species had been recorded. Under each climate change scenario, climatic suitability of the existing range of this species increased, and its climatic niche expanded geographically to the north and higher elevation. GARP predicted a more conservative expansion. The projected spatial and temporal patterns of P. stenoptera can provide reference for the development of forest management and protection strategies. 相似文献
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通过设置对照(CK)、连续性水淹(CF)和间歇性水淹(PF)3个水分处理,模拟三峡库区库岸带土壤水分变化,研究乡土树种枫杨当年实生幼苗的生理生态适应机制.结果表明: 不同水分处理均显著影响枫杨幼苗的光合作用、生物量积累和生长.与CK相比,CF和PF组枫杨幼苗除胞间CO2浓度升高,净光合速率(Pn)、气孔导度(gs)均显著降低.其变化趋势是枫杨幼苗的Pn、gs在试验初期下降,然后逐渐恢复或趋于稳定.随着处理时间的延长,CF和PF组枫杨幼苗的总生物量、根生物量、茎生物量、叶生物量、株高和地径均呈现上升趋势.CF和PF组的总生物量、根生物量、叶生物量和株高,以及PF组的茎生物量均显著低于CK,而CF组的茎生物量与CK无显著差异,其地径还高于CK.枫杨幼苗具有耐受水湿而不耐水淹-干旱交替的生理生态特征. 相似文献
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联用SPME与GC-MS技术分析新鲜、萎蔫、干枯枫杨挥发性成分 总被引:1,自引:0,他引:1
运用SPME与GC/MS联用技术从新鲜枫杨叶挥发性物质中共检测出化合物52种,主要成分是橙花叔醇(15.54%)、吉马烯A(14.22%)、反式子丁香烯(10.19%)、7,8,9,10-四氢化-S-三氮唑(3,4-A)-呔嗪(8.59%)、十六酸(6.22%);萎蔫枫杨叶挥发性物质中共检测出化合物32种,主要成分是α-红没药烯(17.69%)、橙花叔醇(16.64%)、反式子丁香烯(14.26%)、α-桉叶烯(9.14%);干枯枫杨叶挥发性物质中共检测出化合物31种,主要成分是反式子丁香烯(23.30%)、α-红没药烯(17.75%)、α-桉叶烯(12.69%)、橙花叔醇(8.35%)、杜松烯(7.O%).随着枫杨萎蔫程度的变化,三者含有的化合物组分以及其相对含量都发生变化.本研究是首次报道枫杨的挥发性化学成分分析. 相似文献
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The structure of temperate deciduous forests dominated byFraxinus spaethiana andPterocarya rhoifolia in V-shaped valleys in the Chichibu Mountains, central Japan was studied to clarify their dynamics, with special reference
to disturbance. Forest structure and annual ring analysis revealed that the forests have been subjected to mass movement (mud
flow) in the past. The size and age structure, and diameter growth curves, indicated thatF. spaethiana is relatively shade tolerant, long living and slow-growing, whileP. rhoifolia is less shade tolerant, short living, but fast growing.Pterocarya rhoifolia appears to depend on large-scale but rare disturbances.Fraxinus spaethiana establishes its seedlings on relatively unstable substrate in V-shaped valleys, but once established, they survive a long
time with high shade tolerance. The dominance and coexistence of the two species may primarily depend on the intensity and
frequency of geomorphological processes. 相似文献
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漓江河岸带枫杨群落主要木本植物种间联结与相关分析 总被引:2,自引:0,他引:2
种间联结能够反映植物群落中物种间的关系和群落的稳定程度,对植被的恢复与重建、生物多样性保护等具有重要的意义和价值。为了解漓江河岸带枫杨群落的种间联结特征,基于2×2联列表,通过方差比率(VR)、χ~2检验、Pearson相关系数、Spearman秩相关系数检验及PCA排序等,对枫杨群落主要木本植物种间关联性进行定量分析和生态种组划分。结果表明:(1)乔木层、灌木层以及乔木和灌木层的总体种间关联性均呈不显著正联结,表明枫杨群落处于较稳定的阶段;(2)χ~2检验结果显示,绝大多数种对呈不显著关联,说明群落各种对间关联较弱,各物种间呈独立分布格局;(3)Pearson相关检验和Spearman秩相关检验发现各层次的显著率均较低,种间相关性不显著的种对占绝大部分,种间相关性不强;(4)χ~2检验、Pearson相关系数检验和Spearman秩相关系数检验结果虽具有一致性,但也存在一定的差异,Spearman秩相关系数检验更具灵敏性,结合3种方法使用效果更佳;(5)根据PCA排序和种间联结关系,将20个主要物种划分为4个生态种组。 相似文献
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漓江河岸带枫杨群落主要木本植物种群生态位 总被引:5,自引:0,他引:5
为了解漓江河岸带枫杨群落主要木本植物种群的生态位特征,在对其进行群落调查的基础上,利用Levins和Shannon生态位宽度、Schoener生态位相似性和Pianka生态位重叠指数对漓江河岸带枫杨群落乔木层、灌木层主要种群生态位进行定量分析.结果表明: 乔木层的枫杨、灌木层的石榕树和桑的生态位宽度较大;重要值较大的物种,其生态位宽度一般较大,但两者排名顺序并不完全一致.乔木层主要种群生态位相似性普遍小于灌木层,平均值分别为0.151和0.236,主要种群间的生态位相似性较小,各种群对资源利用的相似程度不高;乔木层主要种群生态位重叠普遍小于灌木层,它们的平均值分别为0.217和0.273,主要种群间的生态位重叠程度较低;生态位宽度与生态位相似性之间无显著相关关系,生态位宽度大的物种与其他物种发生重叠的概率更大,但生态位重叠值不一定大,生态位相似性大的物种,其生态位重叠值一般较大.漓江河岸带枫杨群落属于地带性顶极群落,种间关系相对稳定,种群更新缓慢,在发展中有衰退趋势. 相似文献
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Plant communities on riversides in northern Guangdong Province were investigated with all-survey method, where a kind of native grasshopper Fruhstorferiola tonkinensis Will. broke out severely. 108 plant species belonging to 43 families were identified, and some plant indexes in those plant communities including their name, average height, congregation index, total coverage rate, phenological phase and biod were noted. In addition, plant comparability, plant abundance, quantity character and attribute symbol of dominant species in plant communities on riversides were studied. The results showed that the arrangement and distribution of vegetations on riversides offered a favorable habitat for F. tonkinensis. Moreover, the density of first instar nymphs of F. tonkinensis in plant communities was calculated. The results of partial correlation analysis (PCA) about the relationship between plant communities and occurrence of F. tonkinensis showed that Pterocarya stenoptera C. DC. was the most palatable plant to F. tonkinensis, presenting a very significantly positive correlation between coverage rate of P. stenoptera and occurrence of F. tonkinensis. The partial correlation coefficient (PCC) was 0.856072 (F=32.92012, P=0.0001). Bambusa flexuosa was a non-preferable plant of F. tonkinensis, presenting a significantly negative correlation between them, and the partial correlation coefficient was ?0.607920 (F=0.16173, P=0.0211). Those results would help us to propose some approaches for the ecology control of F. tonkinensis on riversides in northern Guangdong Province. 相似文献
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小果青钱柳的分类地位 总被引:1,自引:0,他引:1
<正> 钟补求教授于1936年根据采自安徽黄山的模式标本而发表小果青钱柳Pterocarya mi-cropaliurus Tsoong新种时指出,该种与青钱柳的主要区别在于:(1)果实(包括果翅)较小,直径不超过2.5匣米,而在青钱柳则为3—7匣米;(2)果序较短,长约为青钱柳之半;(3)小叶数目较多,通常9—11枚,且较青钱柳为狭小;(4)小叶的锯齿较密较尖,最大的小叶通常每边有60个以上的锯齿,而在青钱柳则通常不到40个。但根据《中国植物志》第二十一卷(以下简称《植物志》),小果青钱柳应为青钱柳Cyclocarya paliurus(Batal.)Iljinsk.的异名。该《植物志》写道:“本种的小叶大小及数目、果翅的形状及大小变异极大,某些极端类型看来好象可以划分成各别的种,但都存在有中间类型,并且也无一定的地理分布限定,因此它必然是一个自然的种”。为此,我们对有关的腊叶材料进行了 相似文献
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以盆栽1年生枫杨幼苗为实验材料,通过人工设置土壤水分来模拟三峡库区消落带不同土壤水分对枫杨幼苗的光合参数、光合色素含量、叶绿素荧光特性等的影响.试验设置4个处理组,分别为常规供水、常规供水-轻度干旱-复水、水淹、水淹-轻度干旱-复水,3个处理期分别为前期(0-33 d)、中期(34-63 d)、后期(64-78 d).结果表明,不同的水分处理显著地影响了枫杨幼苗“表观性”的气体交换、光合色素含量和水分利用效率等特性,但相较而言对枫杨幼苗“内在性”的叶绿素荧光特性影响较小,且影响的结果和程度因处理组和指标而异.78 d时,除胞间CO2浓度(Gi)、叶绿素a/叶绿素b、光化学猝灭值(qP)和非光化学淬灭值(qN)外,水淹组(FL组)的各项指标在4个处理组中都为最低值;“湿-干”交替组(FD组)的净光合速率(Pn)、蒸腾速率(Tr)、气孔导度(Gs)及总叶绿素含量则表现出先降低复水后显著增加的趋势;DR组的变化趋势与FD组类似,但变化的幅度较FD组小.研究发现,枫杨幼苗面对不同水分状况呈现出了一定的敏感特性,但随着胁迫时间的延长其无论是从光合、水分利用还是叶绿素荧光特性方面都表现出积极的响应,较能适应干旱、水淹、“湿-干”交替等多种环境胁迫,且在胁迫解除后能够迅速恢复生长,可以考虑用于三峡库区消落带的植被重建. 相似文献