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1

Seasonal nutrient resorption and lignin change in leaves of Turkey Oak on northern and southern slope aspects

Sürmen Burak

Polish Journal of Ecology

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2022

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Vol. 70, nr 2-3

89--102

EN

Nutrient resorption is a critical factor for nutrient use strategies developed by plants. Especially nitrogen (N) and phosphorus (P) are the most essential reabsorbed nutrient elements. The leaves' N and P concentrations are closely related to foliar lignin contents. The study aimed to investigate the effects of northern and southern slope aspects on the foliar nutrient resorption in the Mediterranean species of Turkey oak (Quercus cerris var. cerris). The relationships among selected leaf traits, foliar nutrient resorption of N and P, the seasonal lignin change, and the soil traits were analyzed. A principal component analysis was performed to interpret the effect of soil properties on foliar N, P, and lignin concentrations. N resorption efficiency (78.84%) was higher on the northern slope. P resorption efficiency (53.87%) and seasonal lignin change (69.87) were higher on the southern slope. As a result, the slope aspect affects the foliar N, P, and lignin concentrations. Also, foliar lignin concentration was negatively correlated with N resorption efficiency and positively correlated with P resorption efficiency.

2

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

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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Vol. 62, nr 3

479--492

EN

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.

3

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

Liu W., Li S., Su L., Su J.

Polish Journal of Ecology

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2013

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Vol. 61, nr 2

329--339

EN

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.

4

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

Du N., Wang R.-Q., Zhang X.-R, Xu F., Tan X.-F., Guo W.-H.

Polish Journal of Ecology

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2013

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Vol. 61, nr 1

23--34

EN

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.

5

Plasticity to an irradiance gradient in foliageattributes of a perennial monocot Iris pumila (l.):comparison of populations from habitats ofcontrasting light conditions

Avramov Stevan, Tucić Branka

Polish Journal of Ecology

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2006

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Vol. 54, nr 3

403-416

EN

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 umol 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