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1

Life span of needles of Pinus mugo Turra: effect of altitude and species origin

100%
Boratynski A., Jasinska A., Boratynska K., Iszkulo G., Piorkowska M.
Polish Journal of Ecology
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2009
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tom 57
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nr 3
567-572
The needle life span of evergreen coniferous trees is a species-specific trait but can be also affected and modified by environmental conditions. On the basis of field observations of needle life span during three periods in two populations of Pinus mugo in the Tatra Mts (altitude: 1600–1700 m) and Sudety Mts (altitude 830–1420 m), 11 populations from various altitudes we concluded that: 1) within the same population needle life span remained the same over the three periods of observations, 2) needle life span in the Tatra Mts is about 1 year longer than in the Sudety Mts, ranging from 5.5 to 5.9 years and 3) needle life span in the Sudety Mts increases significantly with the altitude of the population. The longer life span of needles in the Tatra Mts may be specific for the population, i.e. it may be due to a different population origin (another Pleistocene centre of the species), and the shorter life span of needles noted in the Sudety Mts may be due to higher soil pollution in this region.
2

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

100%
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
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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)

100%
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

Differences in defence strategies against herbivores between two pioneer tree species: Alnus glutinosa [L.] Gaertn. and Betula pendula Roth.

80%
Giertych M. J., Korolewski P., Zytkowiak R., Oleksyn J.
Polish Journal of Ecology
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2006
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tom 54
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nr 2
The different defence strategies of trees against herbivores are very often connected with succession status, leaf life span and the level of secondary metabolites. We examined the effect of simulated leaf grazing on the differences in the leaf life span and defence chemistry of two pioneer tree species that belongs to the same family (Betulaceae), black alder (Alnus glutinosa (L.) Gaertn.) and European white birch (Betula pendula Roth.). At the beginning of the growing season, mature leaves were perforated using a paper punch. The holes removed about 10% of the leaf surface. Each species was represented by six trees – one branch was chosen for perforation and one branch as a control. All leaves were counted every week until their abscission. Additional damages caused by grazing insects were also noted. Undamaged birch leaves were held much longer than those of alder. The average difference in half leaf life span between control and perforated leaves was 28 days in birch and 6 days in alder. The control unperforated alder leaves were significantly (P <0.05) more often grazed by insects than those that were perforated. Leaf perforation in alder increase phenolic concentrations in the new, young leaves. In birch we did not observe these changes. The comparison of alder and birch indicate that the species with similar successional status can have different strategies of leaf defence. The birch leaves were characterized by a longer leaf life span, constitutive defence, a lack of induced defence accumulation of phenolics and earlier shedding of damaged leaves in comparison to the control. The black alder foliage had a shorter leaf life span, induced defence reaction (produced more phenolics after perforation), and only slightly earlier shedding of damaged leaves than the control.
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