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1.
不同海拔长白山岳桦的生理变化   总被引:8,自引:1,他引:7  
通过分析长白山国家级自然保护区内不同海拔(A1:1700 m, A2:1800 m, A3:1900 m, A4:2000 m, A5:2050 m)梯度岳桦叶片中各种生理指标含量的变化,探讨了林线树木适应高山环境的生理机制.结果表明:随着海拔的升高,比叶面积(SLA)显著减小,A5与A1相比下降了35.90%,差异达到显著水平;叶绿素含量随海拔梯度升高而降低,但叶绿素a/b比值(Chla/Chlb)和Car的相对含量(Car/Chl)随海拔梯度升高而增加;在海拔1900 m左右,MDA含量和MP均处于最低水平,各种酶的活性均为最低;当海拔超过2000 m,接近森林分布的界限时,MDA含量和MP升高,并达到最大值,各种酶的活性都出现了一定程度的下降.综合本次研究表明, 在海拔1900 m比较适合岳桦的生长;海拔超过2000 m,岳桦体内生理抗性下降,不利于岳桦的生长发育,因此高海拔限制了岳桦的分布.  相似文献   

2.
不同海拔微孔草抗氧化系统的比较研究   总被引:1,自引:0,他引:1  
对生长在3个不同海拔自然生境下微孔草(Microula sikkimensis)叶中的抗氧化系统进行了比较研究.结果表明,生长在高海拔的微孔草叶中抗氧化酶类SOD、POD和CAT活性比生长在低海拔的活性高,其中大通牛场的微孔草叶中3种酶活性最高;APX的活性随海拔的升高而升高,且低海拔地区西宁的APX活性极显著低于高海拔地区大通和海北站(P<0.01);作为非酶抗氧化系统物质之一的抗坏血酸(ASA)含量随海拔的升高而降低.高海拔地区微孔草叶中可溶性糖含量极高(P<0.01);可溶性蛋白含量随海拔升高呈V字形变化.光合色素Chla、Chl b和Car的含量均随着海拔升高而增加,Chl a/b比值随海拔升高而降低.MDA的含量随海拔升高有增加的趋势,西宁和大通的相比较,MDA含量差异显著(P<0.05),说明微孔草叶细胞膜脂过氧化程度随海拔升高加剧.生长在不同海拔高度的微孔草对不同海拔高度环境变化具有相应的生理适应性和抗氧化策略.  相似文献   

3.
在卧龙自然保护区,按海拔梯度选择了三个刺叶高山栎分布地点(2600m、3050m和3500m),对各研究地点刺叶高山栎进行了叶片d13C、光合、CO2扩散导度、养分以及形态等参数的测量,以期揭示刺叶高山栎叶片d13C随着海拔的响应规律及原因。结果表明:首先,随着海拔的升高,目标树种叶片d13C随之增加,且海拔每升高1000m,d13C增加2.0‰;其次,随着海拔升高,大气压强降低,因而导致的叶片扩散导度(包括气孔导度(gs)和叶肉细胞导度(gm))的降低是叶片d13C随着海拔升高而升高的主要原因;同时,随着海拔升高而增加的叶片厚度(LMA)也在一定程度上促进了这种响应趋势;最后,叶片N含量随着海拔升高而更多被分配给非光合系统的趋势促进了羧化效率及光合速率的降低,进而对刺叶高山栎叶片d13C海拔响应起到了一定的抑制作用,但程度不大;此外,光合氮利用效率(PNUE)在反映植物叶片的氮含量与其吸收和固定大气CO2能力之间的关系方面及对d13C的指示作用方面较单位面积氮含量(Narea)和单位重量氮含量(Nmass)更鲜明和准确。  相似文献   

4.
叶片性状是决定植物光合能力和羧化能力的关键因素,研究叶片性状在海拔梯度上的变化特征是解释植物对于环境变化的适应策略的重要手段。本文以分布于红池坝(10958′E, 3130′ N)草地的5个常见物种红三叶(Trifolium pratense)、老鹳草(Geranium wilfordii)、紫菀(Aster tataricus)、火绒草(Leontopodium leontopodioides)和绣线菊(Spiraea prunifolia)为研究对象,分析了所有物种(n=56)和不同物种的叶片比叶重(LMA)、叶氮含量(单位面积氮含量Narea、单位重量氮含量Nmass)以及叶片δ13C含量沿海拔梯度(815-2545m)的变化趋势及叶片性状之间的关系。研究结果表明:所有物种样品(n=56)的比叶重(LMA)、Narea和δ13C含量沿海拔梯度的增加呈显著增加趋势;Nmass沿海拔梯度的变化趋势不明显;δ13C含量与LMA、Narea呈现极显著正相关关系;不同物种的叶片性状沿着海拔梯度的响应特征有所不同,绣线菊(S. prunifolia)和老鹳草(G. wilfordii)的叶片性状沿海拔梯度的分布规律与所有物种(n=56)样品分布规律一致,红三叶(T. pratense)、紫菀(A. tataricus)、火绒草(L. leontopodioides)的各叶片性状沿海拔梯度的分布特征有所不同。  相似文献   

5.
卧龙竹类非结构性碳水化合物与叶氮含量对海拔的响应   总被引:3,自引:0,他引:3  
山地由于海拔变化导致的环境因子显著差异,成为研究植物环境适应性及其对全球气候变化响应的理想区域。以卧龙自然保护区内油竹子(Fargesia angustissima Yi)与华西箭竹(Fargesia nitida(Mitford)Keng f.ex Yi)为对象,沿海拔梯度研究了两种竹子在各自海拔分布区间内组织非结构性碳水化合物(NSC)含量、比叶面积(SLA)、以及基于单位叶面积和单位叶质量的叶氮含量(Narea,Nmass)。除油竹子叶NSC,Narea和华西箭竹Nmass随海拔升高不发生变化外,两种竹子其它调查因子对海拔的响应均是非线性的,反映了环境因子随海拔的非线性变化。所有调查因子对海拔的响应均表现出明显的种间差别,这一结果除了种间生理生态特性差别的原因外,可能意味着两竹种对温度的敏感性不同。高海拔种(华西箭竹)比(中)低海拔种(油竹子)对全球气候暖化可能更加敏感。  相似文献   

6.
通过分析庞泉沟国家级自然保护区不同海拔(1 600~2 800 m)梯度华北落叶松针叶中3种抗氧化酶及光合色素含量的变化,探讨了高山林木适应环境的生理机制.结果表明,华北落叶松针叶中超氧化物歧化酶、过氧化物酶和过氧化氢酶的活性随海拔梯度的变化规律相一致,即中海拔区(1 900~2 400 m)的3种抗氧化酶活性相对较低,而低海拔区(1 600~1 800 m)和高海拔区(2 500~2 800 m)活性相对较高.低海拔区3种酶活性分别比中海拔区提高62.79%、42.13% 和 7.87%,高海拔区分别提高75.20%、14.49% 和 63.38%,但临近森林垂直分布上限活性降低.膜脂过氧化产物丙二醛含量在低海拔区和高海拔区分别达9.27和14.06 μmol·g-1 FM,而在中海拔区平均含量为5.58 μmol·g-1 FM.叶绿素和类胡萝卜素含量随海拔梯度升高而降低,相关系数分别为-0.969和-0.986;但叶绿素a/b比值及Car的相对含量(Car/Chl)随海拔梯度升高而增加,相关系数分别为0.962和0.877.  相似文献   

7.
太岳山典型阔叶乔木冠层叶片性状的分布格局   总被引:1,自引:1,他引:0  
以太岳山4种阔叶乔木不同冠层高度的叶片为研究对象,用LI-3000A叶面积仪和Li-6400便携式光合作用测定系统分别测定了这4种乔木不同冠层高度叶片的叶面积大小和单位面积的叶光饱和速率(Aarea);同时测定了其叶氮含量;计算了其比叶面积(SLA)、单位面积叶氮含量(Narea)、单位重量叶氮含量(Nmass)、单位重量的叶光饱和速率(Amass)和光合氮素利用效率(PNUE),对植株不同冠层高度叶片的SLA、叶氮和光合特性的空间分布格局进行了比较研究,结果表明:Aarea、Amass、Nmass、PNUE、SLA和Narea在树冠上层、中层和下层的差异均达到了极显著水平(P<0.001),表明树冠不同高度的叶片性状参数差异较大;在相同SLA下,Nmass和Narea在冠层中的分布均表现为中层>上层>下层,并出现平行位移现象;Aarea和Nmass都以中层值最大,表明冠层光合能力分布格局以中层相对较高。  相似文献   

8.
模拟酸雨对龙眼叶绿体活性的影响   总被引:24,自引:0,他引:24  
邱栋梁  刘星辉 《应用生态学报》2002,13(12):1559-1562
研究了模拟酸雨对龙眼叶绿体活性的影响,结果表明,pH≤3.5的酸雨胁迫使用叶绿素(Chl),类胡萝卜素(Car)含量下降,Chl含量的下降是Chla含量下降的结果,Chlb对酸雨的反应不敏感,因而Chla/Chlb下降,Chl和Car含量,Chla/Chlb随胁迫时间的延长而下降,光照加剧了酸雨对光合色素的伤害,酸雨胁迫使叶绿体光还原活性,光合磷酸化活性,H^ -ATPase活性降低,电子传递链的破坏与磷酸化解偶联,从而使叶绿体不能有效吸收,传递,转换光能,光合磷酸化过程对酸雨胁迫的反应比光还原过程敏感。  相似文献   

9.
在卧龙自然保护区,按海拔梯度选择了4个异型柳分布地点(2350 m、2700 m、3150 m和3530 m),对各研究地点异型柳进行了叶片光合、CO2扩散导度(气孔导度(gs)和叶肉细胞导度(gm))、δ13C、氮素以及比叶面积(SLA)等参数的测量,以期揭示该植物叶片功能性状及功能性状间关系的海拔响应情况.结果表明:随着海拔的升高,大气温度和压强的降低,异型柳的叶片单位面积氮含量(Narea)、最大羧化速率(Vcmax)和最大净光合速率(Amax)均随之增加,这可能是该落叶灌木对于生长季节缩短的一种响应;同时,植物的光合氮利用效率(PNUE)和SLA却均随海拔降低,原因可能在于随着海拔的升高,植物将越来越多的氮素用于细胞壁等非光合组织的构建,这是高海拔植物对于外界恶劣环境的一种适应;最后,扩散导度和羧化能力是植物叶片δ13C的主要影响因子,而羧化能力较扩散导度对于异型柳叶片δ13C的作用更大些,进而导致该值呈现随海拔升高的趋势.氮素在光合与非光合系统间的分配是巴郎山异型柳适应不同海拔生境的关键.  相似文献   

10.
在宁夏灵洲区牛心朴子、甘草自然生境条件下,采用土壤控水措施,研究了土壤水分胁迫对两种优势旱生植物牛心朴子(Cynanchumkomarovii)和甘草(Glycyrrhizauralensis)叶片中的叶绿素;根、茎、叶中的可溶性糖、淀粉含量和C/N比值的影响。结果表明:1土壤水分长期胁迫,导致了这两种旱生植物叶绿素a(Chla)、叶绿素b(Chlb)、类胡萝卜素(Car)含量及Chla/Chlb、Car/Chl比值等的显著变化(P<0.01);2甘草Chla的含量和Chla/Chlb的比值始终大于牛心朴子,相反牛心朴子Chlb、Car的含量和Car/Chl比值却又始终大于甘草;3土壤水分长期胁迫引起了两种植物根、茎、叶可溶性糖含量的升高和淀粉含量的降低;4土壤水分长期胁迫引起了两种植物根、茎、叶C/N比值的降低,但牛心朴子C/N比值在处理的各个时期均大于甘草;5土壤水分长期胁迫引起牛心朴子和甘草Chla、Chlb、Car含量及Chla/Chlb、Car/Chl的比值、可溶性糖、淀粉和C/N比值的增加或减少的程度不同。  相似文献   

11.
To understand the ecophysiological adaptation mechanisms of Calligonum roborovskii to altitude variation, this study analyzed chlorophyll a (Chl a), chlorophyll b (Chl b), Chl (a + b), carotenoid (Car), malondialdehyde (MDA), ascorbate (AsA), proline (Pro), membrane permeability (MP), reactive oxygen species (ROS), specific leaf area (SLA), leaf mass per area (LMA), leaf nitrogen content based on mass (Nmass), and the activities of peroxidase (POD), catalase (CAT), superoxide dismutase (SOD), and ascorbate peroxidase (APX) in leaves of plants inhabiting different altitudes (A1: 2100 m, A2: 2350 m, A3: 2600 m) on the northern slope of the Kunlun Mountains. The results showed that Chl a, Chl b, Chl (a + b), SLA, Nmass, and the activity of CAT increased with increasing altitude. LMA, MP, MDA, Car, Pro, AsA, O2, H2O2 and the activities of SOD, POD, and APX decreased with increasing altitude. The test results also showed that, changes in venvironmental factors along an altitudinal gradient are not obvious. Soil water content is the main ecological factor. With increasing altitude, soil water content increased significantly. More non-enzymatic and enzymatic antioxidants played an important role in eliminating intracellular ROS. They kept the cell membrane in a stable state and ensured the normal growth of C. roborovskii.  相似文献   

12.

Key message

Across sites in Brazil and Hawaii, LMA and N mass were strongly correlated with height and shade index, respectively, which may help simplify canopy function modeling of Eucalyptus plantations.

Abstract

Within tree canopies, leaf mass per area (LMA) and leaf nitrogen per unit area (N area) commonly increase with height. Previous research has suggested that these patterns occur as a strategy to optimize carbon gain by allocating available resources to upper canopy leaves that are exposed to greater light availability. We tested three hypotheses about the influences of height, shade index (a proxy for light), and stand age on LMA and leaf nitrogen for even-aged Eucalyptus saligna and Eucalyptus grandis × urophylla plantations in Brazil and Hawaii, USA, spanning most of the environmental conditions found across 19.6 million ha of Eucalyptus spp. plantations around the world. Shade index was developed by incorporating canopy depth (inner-crown shading) and a tree height ratio relative to neighbor trees (shading from other trees). Across all sites and ages, leaf height accounted for 45 % of the variation in LMA, whereas shade index accounted for only 6 %. A combination of both factors was slightly better in accounting for LMA variation than height alone. LMA–height relationships among sites were strongest under greater light availability and in older stands. Leaf nitrogen per unit mass (N mass) consistently decreased with shade index, whereas N area showed no consistent pattern with height or shade index. These relationships indicate that N mass is primarily driven by light, while height is the primary driver for LMA. The general relationships between LMA and leaf N mass across all sites may simplify canopy function modeling of E. saligna and E. grandis × urophylla plantations.  相似文献   

13.
Question: Is there any generality in terms of leaf trait correlations and the multiple role of leaf traits (response to and/or effect on) during secondary succession? Location: A secondary successional sere was sampled at four different ages since abandonment from several years to nearly 150 years on the Loess Plateau of northwestern China. Method: Specific leaf area (SLA), leaf mass per area (LMA), leaf nitrogen (Nmass, Narea), leaf phosphorus (Pmass, Parea) and leaf dry matter content (LDMC) were measured for all species recorded in the successional sere. Above‐ground net primary productivity (ANPP) and specific rate of litter mass loss (SRLML) were measured as surrogates for ecosystem properties. Soil total carbon (C) and nitrogen (N) were measured in each stage. Leaf traits were related to ecosystem properties and soil nutrient gradients, respectively. Results: LMA is correlated with Narea and Parea' and negatively with Nmass. Correlation between Narea and Parea was higher than between Nmass and Pmass. At the community level, field age, community hierarchy and their interaction explain 64.4 ‐ 93.5% of the variation in leaf traits. At the species level, field age explains 22.4 ‐ 45.5% of the variation in leaf traits (excl. Parea) while plant functional group has a significant effect only for Nmass. LDMC is correlated with ANPP and negatively with SRLML; Pmass is correlated with SRLML. Conclusions: Mean values of LMA, Nmass and Narea are close to the worldwide means, suggesting that large‐scale climate has a profound effect on leaf mass and leaf nitrogen allocation, while environmental gradients represented by succession have little influence on leaf‐trait values. Correlations between leaf traits, such as LMA‐Narea, LMA‐Parea and LMA‐Nmass shown in previous studies, are confirmed here. Although none of the leaf traits is proved to be both a response trait and an effect trait independent of time scale and community hierarchy, mass‐based leaf N is likely a sensitive response trait to soil C and N gradients. In addition, LDMC can be a marker for ANPP and SRLML, while mass‐based leaf P can be a marker for SRLML.  相似文献   

14.
Community structure and leaf traits are important elements of terrestrial ecosystems. Changes of community structure and leaf traits are of particular use in the study of the influence of climate change on terrestrial ecosystems. Patterns of community structure (including species richness, above- and below-ground biomass) and leaf traits (including leaf mass per area (LMA), nitrogen content both on mass and area bases (N mass and N area), and foliar δ13C) from 19 grassland plots along an altitudinal transect at Hongchiba in Chongqing, China, were analyzed. Species richness along the altitudinal transect had a hump-shaped pattern. Above-ground biomass had a quadratic decrease along the altitudinal gradient whereas below-ground biomass had the opposite pattern. Change of above-ground biomass of various taxonomic groups with altitude was also studied. Poaceae showed strong negative relationships and Asteraceae showed a hump-shaped relationship with increase of altitude. Five common species of the grassland, Trifolium pratense, Geranium wilfordii, Aster tataricus, Leontopodium leontopodioides, and Spiraea prunifolia, were particularly studied for variation of leaf traits along the altitudinal gradient. Averaged for all species, LMA, N area and foliar δ13C had positive correlations with altitude. N mass did not change significantly as altitude increased. LMA and N area showed significant positive relationships with foliar δ13C. The adaptive features of leaf traits among different species were not consistent. The study highlights specific adaptation patterns in relation to altitude for different plant species, provides further insights into adaptive trends of community structure and leaf traits in a specific ecological region filling a gap in the definition of global patterns, and adds to the understanding of how adaptive patterns of plants may respond to global climate change.  相似文献   

15.
白坤栋  蒋得斌  万贤崇 《生态学报》2013,33(16):4930-4938
分析广西猫儿山不同海拔常绿和落叶树种的光合作用-氮关系,探讨光合氮利用效率(PNUE)是否受到叶片习性和海拔的影响。落叶树种的PNUE都显著高于常绿树种,这与前者有较低的比叶重(LMA)和较高的单位叶重光合速率(Amass)、氮含量和气孔导度(gs)有密切关系。高海拔树种的PNUE显著低于中低海拔树种的PNUE,这与前者较高的LMA和较低的Amass和gs相关。PNUE和相关的叶片特征的主成分分析表明常绿-落叶树种和低海拔-中海拔-高海拔树种的分布是一个自然过渡的过程。此外,PNUE与土壤碳:氮比没有显著相关性,但与年均温正相关,这表明温度气候是调节PNUE沿海拔变化的主要环境因素。因此,这种叶片习性和温度气候调节的PNUE变化可能是调节猫儿山常绿树种沿海拔形成双峰分布的一种机制。  相似文献   

16.
以漓江水陆交错带为研究区,分两个条带分别量测了适生植物的5个叶性状指标:最大净光合速率(A_(max))、比叶重(LMA)、单位质量叶片全氮含量(N_(mass))、单位质量叶片全磷含量(P_(mass))、单位质量叶片全钾含量(K_(mass))。研究重度淹没带与微度淹没带不同功能型植物叶性状间的差异,分析并讨论重度淹没带叶性状间的关系与全球尺度是否存在差异,探究重度淹没带植物对水淹生境的生理响应机制。结果如下:(1)重度淹没带植物叶片的A_(mass)、N_(mass)、P_(mass)显著高于微度淹没带。(2)乔木、灌木叶片的LMA均显著高于草本植物,而A_(mass)、PPUE均显著低于草本植物。(3)重度淹没带草本叶性状指标的N_(mass)、P_(mass)、PNUE均显著高于微度微度淹没带,而乔木、灌木的叶性状在两个条带的差异则不显著。(4)重度淹没带植物叶性状关系与全球尺度基本一致,其植物叶片具有低LMA,高A_(mass)、Nmas s、P_(mass)。分析可知,重度淹没带植物在出露期提高叶片光合效率及相关营养水平可能是其适应水淹胁迫特殊生境的关键策略之一;不同功能型植物对同一环境的适应能力存在一定的差异,草本对于水淹环境的响应更为积极,适应能力更好;重度淹没带也存在叶经济谱,其植物在经济谱中属于"快速投资-收益"型物种。  相似文献   

17.
Modulation of leaf economic traits and trait relationships by climate   总被引:12,自引:0,他引:12  
Aim Our aim was to quantify climatic influences on key leaf traits and relationships at the global scale. This knowledge provides insight into how plants have adapted to different environmental pressures, and will lead to better calibration of future vegetation–climate models. Location The data set represents vegetation from 175 sites around the world. Methods For more than 2500 vascular plant species, we compiled data on leaf mass per area (LMA), leaf life span (LL), nitrogen concentration (Nmass) and photosynthetic capacity (Amass). Site climate was described with several standard indices. Correlation and regression analyses were used for quantifying relationships between single leaf traits and climate. Standardized major axis (SMA) analyses were used for assessing the effect of climate on bivariate relationships between leaf traits. Principal components analysis (PCA) was used to summarize multidimensional trait variation. Results At hotter, drier and higher irradiance sites, (1) mean LMA and leaf N per area were higher; (2) average LL was shorter at a given LMA, or the increase in LL was less for a given increase in LMA (LL–LMA relationships became less positive); and (3) Amass was lower at a given Nmass, or the increase in Amass was less for a given increase in Nmass. Considering all traits simultaneously, 18% of variation along the principal multivariate trait axis was explained by climate. Main conclusions Trait‐shifts with climate were of sufficient magnitude to have major implications for plant dry mass and nutrient economics, and represent substantial selective pressures associated with adaptation to different climatic regimes.  相似文献   

18.
The spatial patterns of photosynthetic characteristics and leaf physical traits of 171 plants belonging to nine life-forms or functional groups (trees, shrubs, herbs, evergreen trees, deciduous trees, C3 and C4 herbaceous plants, leguminous and non-leguminous species) and their relationships with environmental factors in seven sites, Yangling, Yongshou, Tongchuan, Fuxian, Ansai, Mizhi and Shenmu, ranging from south to north in the Loess Plateau of China were studied. The results showed that the leaf light-saturated photosynthetic rate (Pmax), photosynthetic nitrogen use efficiency (PNUE), chlorophyll content (Chl), and leaf mass per area (LMA) of all the plants in the Loess Plateau varied significantly among three life-form groups, i.e., trees, shrubs and herbs, and two groups, i.e., evergreen trees and deciduous trees, but leaf nitrogen content differed little among different life-form groups. For the 171 plants in the Loess Plateau, leaf Pmax was positively correlated with PNUE. The leaf nitrogen content per unit area (Narea) was positively correlated but Chl was negatively correlated with the LMA. When controlling the LMA, the Narea was positively correlated with the Chl (partial r = 0.20, P < 0.05). With regard to relationships between photosynthetic characteristics and leaf physical traits, the Pmax was positively correlated with N area, while the PNUE was positively correlated with the Chl and negatively correlated with the Narea and LMA. For all the species in the Loess Plateau, the PNUE was negatively correlated with the latitude and annual solar radiation (ASR), but positively correlated with the mean annual rainfall (MAR) and mean annual temperature (MAT). With regard to the leaf physical traits, the leaf Chl was negatively correlated with the latitude and ASR, but positively correlated with the MAR and MAT. However, the Narea and LMA were positively correlated with the latitude and ASR, but negatively correlated with the MAR and MAT. In general, leaf Narea and LMA increased, while PNUE and Chl decreased with increases in the latitude and ASR and decreases in MAR and MAT. Electronic supplementary material The online version of this article () contains supplementary material, which is available to authorized users.  相似文献   

19.
Questions: How are leaf attributes and relative growth rate (RGR) of the dominant tree species of tropical deciduous forest (TDF) affected by seasonal changes in soil moisture content (SMC)? What is the relationship of functional attributes with each other? Can leaf attributes singly or in combination predict the growth rate of tree species of TDF? Location: Sonebhadra district of Uttar Pradesh, India. Methods: Eight leaf attributes, specific leaf area (SLA); leaf carbon concentration (LCC); leaf nitrogen concentration (LNC); leaf phosphorus concentration (LPC); chlorophyll concentration (Chl), mass‐based stomatal conductance (Gsmass); mass based photosynthetic rate (Amass); intrinsic water use efficiency (WUEi); and relative growth rate (RGR), of six dominant tree species of a dry tropical forest on four sites were analysed for species, site and season effects over a 2‐year period. Step‐wise multiple regression was performed for predicting RGR from mean values of SMC and leaf attributes. Path analysis was used to determine which leaf attributes influence RGR directly and which indirectly. Results: Species differed significantly in terms of all leaf attributes and RGR. The response of species varied across sites and seasons. The attributes were positively interrelated, except for WUEi, which was negatively related to all other attributes. The positive correlation was strongest between Gsmass and Amass and the negative correlation was strongest between Gsmass and WUEi. Differences in RGR due to site were not significant when soil moisture was controlled, but differences due to season remained significant. The attributes showed plasticity across moisture gradients, which differed among attributes and species. Gsmass was the most plastic attribute. Among the six species, Terminalia tomentosa exhibited the greatest plasticity in six functional attributes. In the step‐wise multiple regression, Amass, SLA and Chl among leaf attributes and SMC among environmental factors influenced the RGR of tree species. Path analysis indicated the importance of SLA, LNC, Chl and Amass in determining RGR. Conclusion: A mass, SMC, SLA and Chl in combination can be used to predict RGR but could explain only three‐quarters of the variability in RGR, indicating that other traits/factors, not studied here, are also important in modulating growth of tropical trees. RGR of tree species in the dry tropical environment is determined by soil moisture, whereas the response of mature trees of different species is modulated by alterations in key functional attributes such as SLA, LNC and Chl.  相似文献   

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