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树种群体的地理变异是林木选择育种的基础，研究不同种源径向生长的气候敏感性，对于种子调拨及优良种源的选择具有重要意义。本文综述了不同种源径向生长对气候变化的长期和短期响应，指出同一树种不同种源对气候变化具有不同的响应特征。利用不同种源径向生长对气候变化的响应，可指导未来气候下的种源选择。然而，国内有关同一树种不同种源对气候变化的响应研究仍十分缺乏，树木种源生长对气候变化的响应研究亟待进一步深入开展。采用树轮气候学方法探讨不同树木种源径向生长对气候变化的响应，可有效促进我国森林培育管理，指导选择生产力高、适应性强的种源用于更新造林。 相似文献
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树轮因其定年准确、分辨率高、连续性强、样本分布广泛等优势,已被广泛应用于历史气候的重建、生长-气候响应关系和林线动态等研究。树轮形成不仅取决于自身的生长发育,还受温度、降水、光照等环境因子的影响。不同去趋势方法影响树轮年表的质量和其中所含的不同频域气候信号,选择适合的生长趋势拟合方法以及误差分析,从而能从树轮资料中获取较多的气候信息并保证精度是树木年轮气候学研究的关键环节。文中综述了树木年轮气候研究中的主要生长趋势拟合方法,分析了不同方法的优缺点与适用性,并对年表的误差进行了分析,指出在未来树轮气候学研究中生长趋势拟合应注重多种方法和多种误差的结合分析。 相似文献
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随着我国树木年轮学的发展,针叶乔木、阔叶乔木和灌木越来越多树种被应用于树轮-气候响应研究,使得研究区也延伸到了森林以外的区域。本文收集和梳理了我国学者发表的关于树木径向生长对气候响应的研究,从不同角度论述了树木径向生长对气候响应的复杂性,并对未来树轮-气候响应研究进行展望。在气候变暖的背景下,环境的强烈变化让树木生长对气候的响应变得更加复杂,为了更准确地评估未来气候变化情景下外界环境对树木生长的影响及不断拓展我国树木年轮学的研究范围,我国的树木年轮学应继续探索更多的适宜树种,不断完善我国树木年轮资料库,充分发挥树木年轮学在应对未来气候变化和森林生态保护的应用潜力和科研价值。 相似文献
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半干旱区干湿交替、林草交错,生态系统复杂,生物多样性丰富,是受气候变化影响的敏感区域,森林大面积非正常死亡现象正在普遍发生。文中围绕半干旱区森林死亡原因、不同树种水分利用策略与生长特征以及应对干旱胁迫的机制等核心问题,综述了半干旱区森林分布格局及其成因,在气候变化背景下森林的死亡与更新,树木生长季开始与结束时间的界定,树木生长特征与环境的响应和森林动态与水分利用效率等基础研究;提出应加强森林动态与生态防护功能、不同树种水分利用效率与利用机制、优势树种物候及生长特征、森林生态监测和风险预警等科学问题的研究,以期为半干旱区森林动态深入研究提供参考。 相似文献
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摘要：杉木是中国南方湿润地区的主要造林树种之 一 。研究杉木生长与气候响应关系,对预测未来气候变化背景下杉 木的生长特点具有重要意义 。本研究以安徽霍山县茅山林场现存百年杉木林为研究对象,利用人工钻取的 58支杉木树轮 样芯,基于树轮交叉定年技术,构建了杉木树轮标准化年表,分析树轮宽度与气候要素间的关系,以探讨杉木分布北缘林木 径向生长对气候的响应关系 。结果表明:杉木年轮宽度与当年 4 月 降水量以及 9 月 日 照 时数均呈正相关关系 。 多元线性 回归及优势度分析得出,当年 4月 降水和 9月 日 照时数分别贡献了杉木生长的 9.6%和 12.1% 。 由上可知,杉木北缘产地 的杉木在生长季早期生长主要依赖于水分供应,而在生长季晚期则主要依赖于光照。 相似文献
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【目的】研究峨眉山不同海拔冷杉Abies fabri径向生长对气候变化的响应规律。【方法】以冷杉为研究对象,用树轮生态学的方法对峨眉山不同海拔的冷杉进行年轮采样、处理与分析,比较不同海拔冷杉径向生长特征及其与各气候因子之间的关系。【结果】年表统计数据表明,4个年表均具有较高的可靠性,可以用于树木生长与气候关系的研究。不同海拔冷杉径向生长与气候的关系具有明显的海拔差异,海拔2 400 m处冷杉径向生长与当年7月的温度呈显著正相关;海拔2 800 m处冷杉径向生长与当年4-9月的帕尔默干旱指数(PDSI)呈显著正相关;海拔2 900 m处冷杉径向生长与前一年9月和当年4月的温度呈显著负相关,与当年1-9月的PDSI均呈显著正相关;海拔3 000 m处冷杉径向生长和当年3-4月温度呈显著负相关,与当年6-7月的PDSI和当年4月平均相对湿度呈显著正相关。【结论】峨眉山高海拔的冷杉包含有更多的环境信息,对气候变化的响应也更为敏感;高海拔区域冷杉径向生长受到水分的强烈限制,而低海拔区域冷杉径向生长主要受温度影响;冷杉衰亡与气候因子的变化密切相关,随着区域气候的变暖,高海拔地区冷杉可能会进一步衰退。该研究揭示了峨眉山不同海拔冷杉生长动态及其对气候变化响应的敏感性差异,为全球气候变化背景下冷杉林的保护与适应性管理提供科学参考。 相似文献
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Radial stem growth in response to microclimate and soil moisture in a drought-prone mixed coniferous forest at an inner Alpine site 总被引：1，自引：0，他引：1
Walter Oberhuber Andreas Gruber Werner Kofler Irene Swidrak 《European Journal of Forest Research》2014,133(3):467-479
Dendroclimatological studies in a dry inner Alpine environment (750 m a.s.l.) revealed different growth response of co-occurring coniferous species to climate, which is assumed to be caused by a temporal shift in wood formation among species. The main focus of this study therefore was to monitor intra-annual dynamics of radial increment growth of mature deciduous and evergreen coniferous species (Pinus sylvestris, Larix decidua and Picea abies) during two consecutive years with contrasting climatic conditions. Radial stem growth was continuously followed by band dendrometers and modelled using Gompertz functions to determine time of maximum growth. Histological analyses of tree ring formation allowed determination of temporal dynamics of cambial activity and xylem cell development. Daily fluctuations in stem radius and radial stem increments were extracted from dendrometer traces, and correlations with environmental variables were performed. While a shift in temporal dynamics of radial growth onset and cessation was detected among co-occurring species, intra-annual radial growth peaked synchronously in late May 2011 and early June 2012. Moist atmospheric conditions, i.e. high relative air humidity, low vapour pressure deficit and low air temperature during the main growing period, favoured radial stem increment of all species. Soil water content and soil temperature were not significantly related to radial growth. Although a temporal shift in onset and cessation of wood formation was detected among species, synchronous culmination of radial growth indicates homogenous exogenous and/or endogenous control. The close coupling of radial growth to atmospheric conditions points to the importance of stem water status for intra-annual growth of drought-prone conifers. 相似文献
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【目的】研究南亚热带大青山林区乡土珍贵树种米老排径向生长日变化特征及对环境因子的响应,为理解米老排生长-气候响应的生理机制、森林培育和保护等提供基础数据。【方法】利用点状树木径向生长变化记录仪对米老排径向生长变化进行连续观测,采用气象站同步测量辐射总量、土壤含水量、相对空气湿度、空气温度等环境因子数据。通过径向生长与环境因子的相关分析,研究米老排生长季第一个高峰期(5月)的不同分化等级径向生长日变化规律、不同天气条件下生长变化及径向生长-环境因子相互关系。【结果】1)不同分化等级米老排5月份的径向生长日变化量优势木(17.08μm)>平均木(13.94μm)>被压木(-1.81μm),差异极显著(P<0.01),且不同阶段的起始时间、阶段时长、变化量也有所不同。2)不同天气条件下,三种分化等级米老排径向日净生长量和日变化幅度均表现为雨天>晴天>阴天,受雨水影响,雨天条件下径向变化量远超其自身生长量;同种天气条件下,径向日净生长量优势木最大,日变化幅度则表现为平均木最大。3)不同分化等级米老排径向生长与相对空气湿度、降雨量呈极显著正相关关系,与气温、总辐射呈极显著负相关关系,而20 cm土壤含水率无显著性相关,且各影响因子均存在不同时间滞后效应。【结论】不同分化等级米老排由于林木生长状况的差异,导致其受到环境因子影响程度的不同,进而使得其径向生长变化量产生差异。 相似文献
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Monitoring cambial phenology and intra-annual growth dynamics is a useful approach for characterizing the tree growth response to climate change. However, there have been few reports concerning intra-annual wood formation in lowland temperate forests with high time resolution, especially for the comparison between deciduous and coniferous species. The main objective of this study was to determine how the timing, duration and rate of radial growth change between species as related to leaf phenology and the dynamics of non-structural carbohydrates (NSC) under the same climatic conditions. We studied two deciduous species, Fagus sylvatica L. and Quercus petraea (Matt.) Liebl., and an evergreen conifer, Pinus sylvestris L. During the 2009 growing season, we weekly monitored (i) the stem radial increment using dendrometers, (ii) the xylem growth using microcoring and (iii) the leaf phenology from direct observations of the tree crowns. The NSC content was also measured in the eight last rings of the stem cores in April, June and August 2009. The leaf phenology, NSC storage and intra-annual growth were clearly different between species, highlighting their contrasting carbon allocation. Beech growth began just after budburst, with a maximal growth rate when the leaves were mature and variations in the NSC content were low. Thus, beech radial growth seemed highly dependent on leaf photosynthesis. For oak, earlywood quickly developed before budburst, which probably led to the starch decrease quantified in the stem from April to June. For pine, growth began before the needles unfolding and the lack of NSC decrease during the growing season suggested that the substrates for radial growth were new assimilates of the needles from the previous year. Only for oak, the pattern determined from the intra-annual growth measured using microcoring differed from the pattern determined from dendrometer data. For all species, the ring width was significantly influenced by growth duration and not by growth rate, which differs from previous studies. The observed between-species difference at the intra-annual scale is key information for anticipating suitability of future species in temperate forests. 相似文献
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Andreas Gruber Jolanda Zimmermann Gerhard Wieser Walter Oberhuber 《Annals of Forest Science》2009,66(5):503-503
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Growth of commercial forestry is highly dependent on the availability of fast-growing planting materials. Consequently, the efficient utilization of fast-growing plantations can greatly impact productivity. The objectives of this study were to evaluate variations in the growth potential of two clones and to estimate the average stem radial growth advantage of a fast-growing clone using data obtained from Sappi landholdings in eastern South Africa and a mixed modelling approach that permits the incorporation of covariance structure into the statistical model. During the first 2 years of growth, the stem radius of nine trees each of two clones was measured using dendrometer attached to the tree. A second-degree fractional polynomial model was chosen to show the functional relationship between stem radius and tree age. Growth of the two hybrid clones differed significantly. The Eucalyptus grandis × Eucalyptus urophylla clone grew faster than the E. grandis × camaldulensis clone, indicating better genetic potential for rapid growth and yield. This study can be considered as starting point to further compare the potential for rapid growth of several hybrid clones using the longitudinal data modelling approach. 相似文献
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《Journal of Sustainable Forestry》2013,32(1-2):23-34
Abstract A new sensitive dendrometer system was invented by using a potentiometer and datalogger and applied to the stem of some canopy trees of a stand of deciduous broad-leaf tree species native to Hokkaido, northern Japan. Different types of diameter/age growth curves were observed at the fine level for different species: (1) an ordinary type with smooth and gradual growth; and (2) a slow growth curve mixed with intermittent stair-like periods of rapid growth. Possible reasons for the presence of stair-like rapid growth were examined, including the significance of water availability condition. 相似文献
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Reza Oladi Elham Elzami Kambiz Pourtahmasi Achim Bräuning 《European Journal of Forest Research》2017,136(2):345-356
A better understanding of the ecophysiological basis of wood formation by monitoring radial growth over the whole vegetation period may help to explain possible discrepancies between long-term average climate–growth relationships and short-term climatic impacts on tree growth. To understand how growth–climate associations of Oriental beech vary throughout a vegetation period, we studied seasonal growth patterns of high-elevation beech trees growing in the north of Iran by collecting wood anatomical micro-cores in 10 to bi-weekly intervals and measuring stem increment with high-resolution electronic dendrometers. Wood formation was for two consecutive years with contrasting inter-annual climate conditions (2011 and 2012). We divided the growing period into three equal time phases and related daily climate variability to the cambial growth in each phase. The pattern of climate–growth relationships varies over a complete growing season and between years: in both study years, trees responded homogenously at the beginning and at the end of the growing season, but showed opposing influence of relative humidity during spring and early summer (June and July). Temperature as the main driver of xylogenesis had a stimulating effect on growth at the beginning of the growing season, but had negative effects on radial increment during late June and July mainly due to the excess of ambient temperatures over an optimum threshold. Higher temperature in late June and July 2011 compared with those of 2012 led to a significantly narrower tree ring in 2011, despite the similar sums/means of annual climate parameters in these two years. Since regional climate change scenarios expect higher temperature and reduced moisture conditions in future, radial growth of beech in the north of Iran may be adversely affected. 相似文献
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《林业研究》2020,31(5)
The explicit purpose of this study was to characterize climate and vegetation along the western slope of the El Sira Mountains(Peru) and evaluate radial tree growth in response to seasonal rainfall anomalies. From May 2011 until September 2015, we monitored radial stem growth of 67 trees using point dendrometers and measured climate within five sites along an altitudinal gradient. The transect extends from lowland terra firme forests, over submontane forests, late and mid successional montane cloud forests up to exposed elfin forests. Monthly rainfall estimates by the TRMM PR satellite(product 3B42) were highly correlated with our rain gauge observations but underestimate rainfall at high altitudes. Different intra-annual tree growth patterns could be identified within each elevational forest type, showing species with strictly seasonal growth, continuous growth or alternating growth patterns independent of the seasons. Stem growth at each site was generally larger during rainy seasons, except for the elfin forest. The rainy season from October 2013 to March 2014 was extraordinarily dry, with only 73% of long-term mean precipitation received, which resulted in reduced radial growth, again with the exception of the elfin forest. This indicates that montane tropical rain forests may suffer from prolonged droughts, while exposed ridges with elfin forests still receive plenty of precipitation and benefit from receiving more solar radiation for photosynthesis. 相似文献
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This study explores the diversity in sensitivity to drought of moist tropical forest tree species. Yearly tree growth records collected over a ten-year period in two one-hectare 70-year-old damar agroforest plots in Sumatra are analysed. These agroforests are mixed tree plantations, dominated by Shorea javanica K. & V., a dipterocarp tree cultivated and tapped for its commercially valuable resin (damar). Many indigenous fruit tree species grow in these agroforests, as well as timber tree species originating from the nearby natural forest. During the census period the multi-species stands were subjected to three El Nino Southern Oscillation (ENSO)-related droughts (1994, 1997 and 2002). At the tree community level, these droughts were associated with a marked decrease in radial stem growth. Multilevel modelling was used to explore the relative contribution of species, tree size and individual tree characteristics to the observed response to drought.All tree species appeared to be sensitive to drought but the amplitude of the response varied significantly across species. Predicted species mean decrease in stem radial growth rate on drought years (i.e. years with 6 months with less than 50 mm/month rainfall) ranged from less than 5% to more than 80%. Shared species were ranked consistently between plots indicating that the results were robust. Stem diameter significantly affected tree sensitivity to drought in two species only, but in opposite ways: in S. javanica, larger trees appeared to be less sensitive while the opposite was true for Lansium domesticum, an abundant fruit tree. Individual tree sensitivity to drought contributed significantly albeit to a small extent to the overall response to drought. This individual tree effect did not show any pattern of spatial correlation and hence could not be related to topographic features. It is likely to reflect the individual's unique history and genotype. 相似文献
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Irantzu Primicia J. Julio Camarero J. Bosco Imbert Federico J. Castillo 《European Journal of Forest Research》2013,132(1):121-135
We assessed the effects of thinning (0, 20 and 30 % extraction of basal area) and canopy type (pine–beech vs. pine plots, beech accounting for 12 % of total basal area) on radial growth of dominant and codominant Scots pine at inter-annual scale and on microclimatic conditions, radial growth and xylogenesis 9 years after thinning at intra-annual scale. Thinning weakly affected pine growth, which was enhanced 3 years after harvesting. Over time, a gradual reduction in pine growth in mixed canopy relative to pure canopy occurred only in unthinned plots apparently due to beech expansion. Indeed, 9 years after thinning, a higher seasonal radial increment and a greater number of tracheids were produced under pine canopy in the unthinned plots, whereas no differences between canopy types were observed in the thinned plots. Radial increment and tracheid production were mainly affected by tree water status (air and soil humidity, throughfall). The differences of tree water status caused by treatments, and plausibly disparities in tree size and tree-to-tree competition, were the main drivers explaining the patterns observed for radial increment and xylogenesis. Our results suggest that the negative effects of beech competition on Scots pine growth in similar mixed forest may be controlled to some extent by thinning. 相似文献