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1

Correlations between leafing phenology and traits: woody species of evergreen broad-leaved forests in subtropical China

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Liu Z.-G., Li K., Cai Y.-L., Fang Y.
Polish Journal of Ecology
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2011
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tom 59
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nr 3
Leaf phenology has been considered to evolve to maximize plant carbon gains, and it reflects plant life history strategies. To determine the effect of leaf traits on leaf phenology, leaf emergence (such as timing of leaf emergence, leaf expansion rate, durations of leaf expansion), leaf traits (leaf mass per area – LMA and leaf size), and their relationships were investigated for 40 woody species from 13 families in an evergreen broad-leaved forest, southeast China. Compared with understorey shrubs (23 species), trees species (17 species) were significantly later in timing of leaf emergence, greater in leaf area and leaf expansion rate. This is assumed to be a strategy for large-leaved tree species to decrease damage during leaf expansion. In terms of leaf size, the small-leaved species leafed out earlier than the species with large leaves, but the largeleaved species were greater in leaf expansion rate than their counterparts. Leaf expansion rate was positively correlated with leaf area and timing of leaf emergence. Leaf herbivore rate was positively correlated with leaf area and leaf expansion period, but negatively with LMA. These results suggest that large- and small-leaved species possibly employed different strategies to minimize herbivore damage. Small-leaved species avoid defoliator damage by early leafing, while largeleaved species have shorter expansion times and thereby shorten vulnerable time to herbivores. In general, dynamics of emergence and expansion of the woody species in the study forest indicate that the leaf phenology is of significance for species’ carbon gain and survival.
2

Variations of leaf economic spectrum of eight dominant plant species in two successional stages under contrasting nutrient supply

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Mao W., Li Y.-L., Zhao X.-Y., Zhang T.-H., Liu X.-P.
Polish Journal of Ecology
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2016
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tom 64
|
nr 1
Leaf functional traits are indicators of both plant community and ecosystem responses to environmental factors and can thus increase our capacity to understand ecosystem processes and community assembly due to climate change. The variation in leaf functional traits between succession stages in Horqin Sandy Land is caused by soil nutrient content and by intrinsic biological characteristic of species, but the effects are different. Leaf economic spectra were assessed for seven leaf traits of eight species from early and advanced stages of succession. Species from early succession stages are Agriophyllum squarrosum (L.) Moq., Corispermum macrocarpum Bge., Setaria viridis (L.) Beauv. and Pennisetum centrasiaticum Tzvel., and species from advanced successional stages are Chenopodium acuminatum Willd., Chloris virgate Swartz, Digitaria sanguinalis (L.) Scop. and Leymus secalinus (Georgi) Tzvel. All these species were grown in a greenhouse experiment under two contrasting nutrient supplies including high nutrient level (N , with 20 g of nutrient addition) and low nutrient level (N-, with no added nutrients). As expected, the resource uptake strategies of the species were affected by soil fertilization addition. Leaf nitrogen content (LNC), leaf phosphorus content (LPC), and photosynthetic capacity per unit leaf area (Aarea) significantly increased at high nutrient level but LPC is more dramatically changed than others leaf traits. Leaf life span (LLS) and specific leaf area (SLA) did not show similar tendency with succession stage. At the same nutrient level, LES still shows different pattern between the early and the advanced succession stages. Species from early succession stages have higher LPC and Aarea, compared to species from advanced stages. Species from early succession stage also tend to have higher SLA and higher LNC than at the advanced succession stage. The LLS did not show any clear changes with succession process. These results provide evidence that LES shift along the succession process is mainly caused by intrinsic biological characteristic of species.
3

Adaptative strategy of leaf traits to drought conditions: Quercus aliena var. acuteserrata forest (The Qinling Mts. China)

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Wang M., Wan P., Chai Y., Guo Y., Zhang X., Yue M.
Polish Journal of Ecology
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2015
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tom 63
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nr 1
In a climax community where all species are sharing relatively similar and stable habitat, there are differences in leaf traits between deciduous trees and shrubs and dominant species and companion species, especially in leaf lifespan (LLs). What are the differences of relationships among leaf traits between deciduous trees and shrubs? What are the mechanisms of this phenomenon? Here, we presented a one-year observation and recorded the LLs followed a modified method in a Quercus aliena var. acuteserrata forest in the north slope of the Qinling Mountains, China. We found that (i) Different species in the same stand performed quite differently in their LLs (P <0.005). Average LLs of shrubs was slightly longer (P = 0.05) than that of deciduous trees. (ii) LLs showed a significant negative correlation with specific leaf area (SLA) and leaf nitrogen content (LNC) (P <0.05) in deciduous trees, however, a significant positive correlation with LNC and leaf carbon content (LCC) (P <0.05) was detected in shrubs. (iii) The comparison of the traits between dominant and companion species in arbor layer and shrub layer showed that there was no significant difference in LLs, LCC and LNC, except SLA in arbor layer. Our study indicated that the amount of light, at the community scale, might be a main factor determining the LLs of wood plants in deciduous forest. The difference between trees and shrubs in relationships among leaf traits suggests that deciduous trees and shrubs may take different strategies to adapt to the environment. SLA is likely to be a marker trait to distinguish dominant and companion species in arbor layer of deciduous broad leaved forest.
4

Foliar responses of Abie fargesii Franch. to altitude in the Taibai Mts, China

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Xu P., Zhang X., Zhao C., Chen L., Gao X., Yao B., Deng J., Deng Y.
Polish Journal of Ecology
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2014
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tom 62
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nr 3
Physiological and ecological adaptations of altitudinal gradients reveal alpine plants’ ecological and evolutionary responses to environmental changes. Here we quantitatively investigated the variation in the foliar physiological and morphological traits of alpine tree species (Abies fargesii) along the altitudinal gradient in the Taibai Mountains, China. We collected the needle samples of Taibai fir (A. fargesii) from seven sites at altitudes of 2550, 2650, 2750, 2850, 2950, 3050 and 3150 m, respectively, and measured the 12 foliar physiological and morphological traits. Each set of needle sample (100 needles) was randomly selected from the upper- third of A. fargesii canopies. The results showed that leaf mass per unit area (LMA), stable carbon isotope composition (δ13C), stomatal rows (SR), leaf carbon concentration per unit area (Carea), leaf nitrogen concentration per unit leaf mass (Nmass) and area (Narea) linearly increase significantly while stomatal density (SD), number of stomata per unit nitrogen concentration (St/N) and per unit leaf mass (St/LM) decrease with the altitudes raise. Moreover, all measured traits presented both strong correlations and significantly linear relationships with the main climate factors such as the mean temperature, rainfall and relative humidity during the growing season as well as the altitudes, except for leaf free water concentration (LWC), leaf carbon concentration per unit leaf mass (Cmass) and C: N ratio. The patterns of foliar traits in response to altitudes imply that the alpine plants need higher cost (e.g. higher nutrient concentration) to adapt to the harsher environments along altitudinal gradient. Moreover, our results show that the variation patterns of the leaf traits for A. fargesii plants should be driven by the interactions of multi-climate factors because the abiotic factors that directly influence the growth of plants covary with the increasing altitudes.
5

Effect of soil moisture on morpho-anatomical leaf traits of Ranunculus acris (Ranunculaceae)

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Kolodziejek J., Michlewska S.
Polish Journal of Ecology
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2015
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tom 63
|
nr 3
Leaf morphological and anatomical differences between two collection sites in central Poland were examined in tall buttercup Ranunculus acris. We hypothesized that the availability of soil moisture would affect leaf morphological and anatomical traits. The objective of this study was to examine the effect of soil moisture content on: leaf size, epidermal features and on a number of stomatal characteristics in populations of R. acris species. The plants were investigated at sites differing in soil moisture conditions (a dryer upper site and a wetter lower site). Relatively semi-dry and wet sites were identified by plant communities and soil moisture content. We found out that morphological and anatomical leaf traits of R. acris were significantly related to soil moisture content. Leaves from plants growing in the wet site were 26% smaller in size than those from the semi-dry site. The population with smaller leaf area had larger leaf perimeter and higher dissection index. The stomatal index of the leaves sampled in the semi-dry site was higher than that of the leaves sampled in the wet site. Greater leaf thickness in the semi-dry site was primarily the result of increased spongy parenchyma thickness. On the abaxial leaf surface epidermal cell density was significantly higher at the wet site implying more epidermal cells. On the adaxial leaf surface, however, epidermal cell density decreased when plants were exposed to the elevated soil moisture. The results may indicate that soil moisture content influences leaf anatomy and morphology of R. acris. Thus, all these leaf morphoanatomical traits provide a basis for R. acris to reduce water loss from leaves and to balance water use efficiency under reduced precipitation. The present study demonstrates that R. acris can maximize growth in habitats with a wide range of soil moisture availability and such information can be crucial for developing management strategies and predictive models of its spread.
6

Variation and correlations of leaf traits of two Taxus species with different shade tolerance along the light gradient

100%
Liu W., Li S., Su L., Su J.
Polish Journal of Ecology
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2013
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tom 61
|
nr 2
The variations in leaf traits of Taxus species in different light conditions are still poorly understood. We sampled leaves of Taxus yunnanensis W. C. Chang L. K. Fu and Taxus chinensis var. mairei (Lemée and Lév.) W. C. Cheng and L. K. Fu along an illumination gradient (full daylight, 40–60% full daylight, <10% full daylight), and analyzed how seven leaf traits and their correlations changed under different light conditions. The leaf trait that showed the greatest variation was specific leaf area (SLA) for T. yunnanensis, followed by leaf dry mass (LM) for both taxa. The smallest variation was in leaf width (LW) for both taxa. Plasticities of all leaf traits in both taxa were higher than 50%, and those of leaf area (LA), LM and SLA were greater than 80%. The light gradient was positively correlated with leaf length (LL), LM, leaf dry matter content (LDMC), and leaf length to width ratio (LWR). LW and SLA were negatively correlated with the light gradient. Analyses of relationships among leaf traits showed that LM of T. yunnanensis, T. chinensis var. mairei and both taxa was positively correlated with LL, LW, LA, LDMC, and LWR, and negatively correlated with SLA under all light conditions. We concluded that leaf traits and their relationships were affected by light conditions.
7

Plasticity to an irradiance gradient in foliage attributes of a perennial monocot Iris pumila [L.]: Comparison of populations from habitats of contrasting light conditions

100%
Avramov S., Tucic B.
Polish Journal of Ecology
|
2006
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tom 54
|
nr 3
Magnitude and variation in leaf plasticity were quantified in two Iris pumila (L.) populations from habitats of contrasting light conditions (open dune vs wood understorey) at three light intensities (high – 110, medium – 65, and low – 29 μmol m⁻² s⁻¹). Siblings developed from hand-pollinated seeds from 13 and 15 clonal genotypes in an open and a shaded population, respectively, raised in a growth-room were scored for morphological (leaf number, leaf area, specific leaf area), anatomical (stomatal density, leaf thickness, vascular bundle number, sclerenchyma and cuticle widths) and biochemical (chlorophyll content, chlorophyll a:b ratio) traits. Morphological traits in general and SLA (projected leaf area per unit leaf dry mass) in particular were more sensitive to variation in light conditions than any other examined leaf attribute, indicating their key importance for maximizimg light-energy interception at low irradiance. Regardless of the population origin, the average plasticity (percentage trait change between two successive treatments) of morphological traits declined with decreasing irradiance, opposite to anatomical traits, particularly leaf thickness, which increased parallel to light intensity decrease. Mean plasticity variation (across-family CV) changed with light level, ranking in the following order morphological
8

Scaling relationships of leaf traits do not change among months in a temperate shrub species

80%
Du N., Wang R.-Q., Zhang X.-R., Xu F., Tan X.-F., Guo W.-H.
Polish Journal of Ecology
|
2013
|
tom 61
|
nr 1
Leaf traits scaling relationships were compared in different months (May, June, July and August) in a temperate shrub species, Vitex negundo Linn. var. heterophylla (Franch.) Rehd. Leaf traits variation and the impact of environment were also studied. Our results showed that specific leaf area (SLA), leaf nitrogen content (Nmass), leaf phosphorus content (Pmass) and leaf chlorophyll content (Chlmass) were positively correlated, and all of the pairwise relationships showed a common standardized major axis (SMA) slope in different months. The variation of SLA, chlorophyll a content (Chlmass a), chlorophyll b content (Chlmass b), Chlmass a/b and maximum quantum yield of PSII (Fv/Fm) were mainly habitat-dependent, while the variation of Pmass and Nmass/Pmass were mainly month-dependent. Redundancy analysis (RDA) was used to further explore the relationships between leaf traits and environmental factors. We found that plants under shade (the relative photosynthetic photon flux density was about 10%) developed light-capturing behavior at leaf level (higher SLA) and cellular level (higher Chlmass/Nmass and lower Chlmass a/b). The increased Nmass/Pmass with month was mainly resulted from the large absorption of soil nitrogen and the decrease of soil pH. In a word, our study indicates that species may not have fundamentally different carbon capture strategies in different months. Variation of different leaf traits are related to different environmental factors in the field.
9

Differential effects of grazing on plant functional traits in the desert grassland

80%
An H., Li G.
Polish Journal of Ecology
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2014
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tom 62
|
nr 2
Plant functional traits are linked with environmental factors, individuals and ecosystem structure and functions as plants respond and adapt to the environment. Here, the whole-plant traits (plant height and plant biomass), leaf morphological (leaf area, leaf dry mass and specific leaf area) and chemical traits (leaf carbon, nitrogen, phosphorus contents, C/N and N/P ratio) of six dominant species (Cynanchum komarovii Al, Euphorbia esula Linn, Glycyrrhiza uralensis Fisch, Lespedeza potaninii Vass, Agropyron mongolicum Keng and Stipa breviflora Griseb) were studied in the desert grassland of China, with a grazing experiment including four grazing intensity (0.00, 0.45, 1.00, 1.50 sheep ha–1). The effect of grazing on leaf morphological traits were significant for the six dominant species, while the effects on whole-plant traits were highly significant for S. breviflora, A. mongolicum, G. uralensis, L. potaninii and C. komarovii. Three of the six species (S. breviflora, A. mongolicum and L. potaninii) decreased in plant height (PH) with increasing grazing intensity, while specific leaf area (SLA) and leaf N (Nmass) showed the opposite trend. The whole-plant traits were significantly positively correlated with leaf dry mass (LM), but significantly negatively correlated with leaf nitrogen and phosphorus contents. The first principal component analysis (PCA) axis corresponding to plant size (PH and PB) and leaf size (LA and LM), while the second axis of PCA to leaf chemical traits (Nmass, P, C and N/P). Variations of plant traits in response to grazing were mainly explained by size trait and chemical traits. The functional traits cannot be the only basis for predicting plant species in response to grazing, and a functional analysis of the trade-off between plant traits is also needed.
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