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1

Effect of Soil Moisture on Morpho-Anatomical Leaf Traits of Ranunculus acris (Ranunculaceae)

Kołodziejek J., Michlewska S.

Polish Journal of Ecology

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2015

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Vol. 63, nr 3

400--413

EN

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.

2

Functional traits and plasticity of plants in ecological research and education

Masarovičová E., Májeková M., Vykouková I.

Chemistry-Didactics-Ecology-Metrology

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2015

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R. 20, NR 1-2

59--65

EN

Plant functional traits are any morphological, physiological and phenological features, which indirectly affect plant fitness through their three basic components of plant individual performance - growth, reproduction and survival. These features represent also a keystone for plant functional groups, which are similar in three aspects - function on the level of organism, response to environmental factors and effect on ecosystems. Functional approach in ecology and vegetation study enables to evaluate plant communities on the base of species function in a community, and to relate functional structure of plant communities to particular environmental gradients. Species plasticity has many aspects that mirror species adaptations to the environmental conditions and which then also translate into functional structuring of plant communities. This approach is thus a novel and exciting mode how to carry on plant ecology, both in research and education at universities.

PL

Charakterystyczna funkcjonalność roślin zależy od ich cech morfologicznych, fizjologicznych i fenologicznych, które pośrednio wpływają na kondycję roślin poprzez trzy podstawowe elementy ich indywidualnego rozwoju, tj. wzrost, reprodukcję i przetrwanie. Cechy te stanowią również podstawę funkcyjnych grup roślinnych, które są podobne w trzech aspektach - funkcje na poziomie organizmu, odpowiedź na czynniki środowiskowe i wpływ na ekosystemy. Podejście funkcjonalne w ekologii i w badaniach roślin umożliwia ocenę zbiorowisk roślinnych w oparciu o funkcje gatunków w społeczności i odniesienie funkcjonalnej struktury zbiorowisk roślinnych do poszczególnych gradientów środowiskowych. Plastyczność gatunków ma wiele aspektów, które odzwierciedlają ich przystosowanie do warunków środowiskowych, a które następnie przekłada się także na funkcjonalną strukturę zbiorowisk roślinnych. Takie podejście jest więc nowym i interesującym sposobem rozumienia ekologii roślin, znajdującym zastosowania zarówno w badaniach, jak i w edukacji uniwersyteckiej.

3

Comparative study of ecophysiological and biochemical variation between the Baltic and North Sea populations of the invasive soft shell clam Mya arenaria (L. 1758)

Lasota R., Pierścieniak K., Miąc J., Wołowicz M.

Oceanological and Hydrobiological Studies

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2014

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Vol. 43, No. 3

303--311

EN

Seasonal variations of environmental factors, such as temperature and salinity, require metabolic acclimatization in sedentary benthic fauna distributed over a wide geographical range. The soft-shell clam Mya arenaria inhabits the coastal waters of the North Atlantic including North America and Europe. In Europe, M. arenaria populations are distributed from Iceland to the Mediterranean Sea, including the North Sea, the Baltic Sea and the Black Sea. Seasonal changes in physiological parameters (gonad index, condition index, biochemical composition and respiration rate) of M. arenaria from the Baltic Sea (the Gulf of Gdańsk, Poland), and the North Sea (Versee Meer, the Netherlands) were studied. The sex ratio of both populations did not differ from 1:1 and the seasonal gonad index was higher in the Baltic population. The average condition index changed seasonally at both studied sites, and was also higher in the Baltic population (except the autumn) compared to the North Sea. In both studied populations, the content of proteins, lipids and carbohydrates in the soft tissue followed the seasonal variations, and it was higher in the Baltic population. The respiration rate was lower in the Baltic population, and seasonal changes in the respiration rate seem to be correlated with changes in the water temperature. Based on the results obtained in the present study, we suggest that Mya arenaria is characterized by a large phenotypic plasticity and differences in the observed physiological traits are due to acclimatization to ambient environmental conditions.

4

Effects of post-cutting changes in site conditions on the morphology and phenology of naturally regenerated beech seedlings (Fagus sylvatica L.)

Barna M., Schieber B., Cicak A.

Polish Journal of Ecology

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2009

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Vol. 57, nr 3

461-472

EN

We studied the response in growth and phenology of naturally regenerated beech seedlings to changed ecological conditions over 14 and 19-years after cutting with different intensity. Five different types of stand densities were modelled: plot C - control plot - no cut, L - low intensity cut, M - medium intensity cut, H - high intensity cut and CC - clear cut, with 1, 8, 22, 53 and 100% of relative irradiation, and 66, 68, 78, 92 and 100% of through fall, respectively. We were focussing on tree height growth and leaf area. Our phenological observations were aimed at onset and course of two spring vegetative phenophases: bud-burst and leaf unfolding. Already in two-year-old beech seedlings we found significant differences in height growth; the differences in mean leaf area, however, were observed later. From the viewpoint of phenotypic plasticity, the height growth in beech seedlings represented more sensitive response to the environment than the leaf area. According to leaf area size and height growth in the beech seedlings on control plot, the stress conditions were indicated, primarily from the lacking light. With stand opening, the development of recruitment was getting better, and beginning with plot M the increase of seedlings height and leaf area became continuously related to the amount of radiation. The results of phenological observations showed that the spring phenophases in the seedlings start first on control plot. The start of spring phenophases on the clearcut was always observed the latest, even in comparison with the parent stand. Correlation analysis confirmed a significant correlation (P <0.05, r = -0.61) between the mean air temperature in March and April and start of the phenophase leafing in the individual years. Analysis of long-term research showed that the trend of leafing's onset observed in course of 18 years was significant (P <0.05), manifested a shift towards earlier dates.

5

Cogradient pattern of growth in montane and lowland larvae of Rana remporaria (L.) at two levels of temperature

Jasieński M.

Polish Journal of Ecology

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2009

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Vol. 57, nr 2

353-361

EN

Direct environmental impact and microevolutionary pressure may both shape the phenotype by acting synergistically (cogradient) or antagonistically (countergradient). An experimental approach is therefore needed to determine which environmental challenges are responsible for the observed inter-population variation in a phenotypic trait and if such variation is adaptive. Rana temporaria L. larvae were reared in a factorial experiment, with two temperature regimes (differential of 6[degrees]C) and larvae originating from two source populations in Poland: a montane pond in the Babia Gora National Park (elevation 1025 m) and a lowland swamp near Warszawa (elevation 100 m). Populations did not differ in early larval growth rates or in the length of the larval period. In both populations, the early rates of development were higher and the larval period was expectably and substantially shorter at higher temperature. The montane larvae were heavier at metamorphosis than the lowland larvae, but significantly so only at the low temperature treatment. The observed patterns of responses partially conform to the cogradient model of phenotypic variation, in which both environmental and selective effects are mutually enhancing the differentiation of populations.

6

Phenotypic plasticity within Daphnia longispina complex : differences between parental and hybrid clones

Pijanowska J., Bernatowicz P., Fronk J.

Polish Journal of Ecology

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2007

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Vol. 55, nr 4

761-769

EN

The mechanism that enables the coexistence of apparently very similar species is fundamental in understanding the diversity of natural communities. The ranges of reactions of the three Daphnia clones in the presence of toxic compounds and fish kairomones were studied in laboratory. The ranges were based on differences in body length, spine length and fecundity (number of eggs in a brood chamber) during first three reproductions. The ranges of reactions of the three clones differed dramatically. The range of D. galeata and D. hyalina hardly overlapped, while that of a D. galeata x hyalina hybrid clone was significantly broader than the ranges of either parental species. The observed diversity of ranges of reactions probably enables the coexistence of closely related species in the variable environment of natural lakes.

7

The effect of salinity on freshwater crustaceans

Grzesiuk Małgorzata, Mikulski Andrzej

Polish Journal of Ecology

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2006

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Vol. 54, nr 4

669-674

EN

Recent advancing industrialization and urbanization have increased salt concentrations in formerly-freshwater habitats. Freshwater animals are being affected, especially those like crustaceans that are unable to emigrate to escape the problem. The effects of increased salinity, first observed at the molecular level, are found to extend to the levels of the individual, population, community and ecosystem. Crustacean morphology, behaviour and life histories may be influenced, with growth rate, and age and size at first reproduction, being disturbed, along with clutch and neonate size. Mortality rates are also elevated where the salt concentration is high, though susceptibility to salt differs both between species and between clones of the same species. The effect may be to modify the composition of crustacean assemblages in terms of the species and clones present.

8

Simulated herbivory limits phenotypic responsesTo drought in Convolvulus demissus Choisy(Convolvulaceae)

Quezada Iván M., Gianoli Ernesto

Polish Journal of Ecology

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2006

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Vol. 54, nr 3

499-503

EN

Drought and herbivory are important stress factors for plants. When plants are subjected to any form of stress, phenotypic responses are elicited to reduce damage. Responses to drought include a decrease in leaf area and aerial biomass, and an increase in root/shoot ratio of biomass allocation. If plants are subjected to drought and herbivory at the same time, constrained responses are expected due to resource limitation. In a greenhouse experiment we analyzed the effect of simulated herbivory on the ability to respond to drought stress in seedlings of the Chilean perennial herb Convolvulus demissus (Convolvulaceae), which in natural populations may experience water deficit during dry summers as well as grazing by mammals. Plants subjected to drought showed the phenotypic responses theoretically expected. In contrast, plants subjected to a combined drought + herbivory treatment did not show those responses, being phenotypically similar to control plants. It is suggested that herbivory may limit responses to drought in C. demissus, hence magnifying the negative consequences on plant fitness of such abiotic factor.

9

Adaptive changes in morphology of Daphnia filter appendages in response to food stress

Bednarska Anna

Polish Journal of Ecology

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2006

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Vol. 54, nr 4

663-668

EN

Morphological adaptations of Daphnia filtration apparatus in response to unsuitable food conditions are examined and set against earlier published data. To maximize food gathering under limiting food conditions, Daphnia can respond morphologically by plastic changes in the size and structure of its filter apparatus. Under low food quantity and/or poor quality, the area of Daphnia filter screen increases and the mesh size decreases.

10

Phenotypic plasticity of microalgal cultures in culture collections: a geometric morphometric approach

Neustupa J.

Oceanological and Hydrobiological Studies

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2005

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Vol. 34, No.3

97--107

EN

The algal culture collections include numerous old strains whose morphological characteristics may have changed after decades of subculturing. This case study of the fifty-yearold Pringsheim CAUP H 3301 strain of Keratococcus bicaudatus was conducted using geometric morphometric analysis of phenotypic plasticity to detect possible shifts in morphology. The results of relative warp analysis indicate that the young cultured population corresponds well with literature data regarding the morphology and phenotypic plasticity of the species. However, the culture expresses more phenotypic plasticity in both young and old populations.