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1
Artykuł dostępny w postaci pełnego tekstu - kliknij by otworzyć plik
Content available

Using 3D scanning in allometric studies on Helix pomatia

100%
Czyz M., Kalinowski T., Goldyn B., Rybska E.
Folia Malacologica
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2012
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tom 20
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nr 1
2

Biomass allocation, compensatory growth and internal C/N balance of Lolium perenne in response to defoliation and light treatments

84%
Wang L., Wang J., Liu W., Gan Y., Wu Y.
Polish Journal of Ecology
|
2016
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tom 64
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nr 4
Light environments can have a considerable influence on how plants respond to defoliation through influencing the biomass allocation patterns and internal C/N ratio. Seedlings of Lolium perenne, a common perennial grass species, were grown for eight weeks under three different light environments (natural light, red light and shading) and two different defoliation treatments (no defoliation versus 50% aboveground biomass removal). This study was conducted to examine (1) the effects of light regimes and defoliation on biomass accumulation, biomass allocation and internal C/N ratio status in plants; (2) how the light regimes influence the pattern of compensatory growth after defoliation; and (3) the relationship between compensatory growth and the internal C/N ratio status. We found that red light altered the shoot-to-root allometry, enhanced the leaf C concentrations and induced N deficiency. By contrast, the leaf N concentrations of L. perenne were greater during shading treatment, which simultaneously enhanced shoot growth and stopped root growth. Under defoliation, red light increased shoot growth, not at the expense of root growth, which was not the same as in natural light and shading treatment. Moreover, regardless of the unclipped (no defoliation) and defoliation conditions, the L. perenne biomass partitioning between roots and shoots was significantly correlated with the leaf N concentrations and C/N ratio, indicating that allometric biomass allocation can be largely modulated by signals related to the C and N status of the plants. These results demonstrated that the leaf C and N status would be an appropriate indicator of compensatory growth after defoliation.
3

Length-weight relationship and growth parameters of the commercial fish Pagellus erythrinus (Linnaeus, 1758) (Actinopterygii: Sparidae) from Northern and Southern Tunisia

84%
Fassatoui C., Hmida L., Jenhani A. B. R., Romdhane M. S.
Biological Letters
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2019
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tom 54
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nr 1
4

Nitrogen content and biomass: scaling from the tree to the forest level

84%
Cheng D.-L., Zhong Q.-L.
Polish Journal of Ecology
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2012
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tom 60
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nr 4
Nitrogen is an essential nutrient for plant growth. Although much has been learned about its utilization and distribution within the plant body, little is known about the relationship between nitrogen content and standing biomass at the level of entire forests. Data for nitrogen content (N) and biomass (M) of 10 deciduous species in USA at the individual trees level and 37 species grown in three forest biomes (i.e. tropic, subtropics, and temperate) in China at stands level were gathered to determine the N versus M scaling relationships for different tissue- and organ-types (e.g. bark and leaves). Model Type II regression protocols were used to calculate scaling exponents and allometric constants (i.e. slopes and y-intercepts of log-log bivariate plots, respectively) between N and M to. At the level of individual plants, N scaled nearly isometrically with M for the different tissue- and organ-types (i.e. Nα M 0.97–1.04). At the stand-level, N scaled similarly with respect to leaf, branch, and bark M, despite differences in stand size-frequency distributions and species composition. However, total stand N scaled allometrically with respect to total stem or root M and thus to total stand mass (i.e. N α MT 0.77–0.87). This was attributed to the accumulation of wood (and other ‘necromass’ tissue components that have lower N content than physiologically active tissues) in progressively older (and thus more massive) tree stands. When coupled to the scaling of N with respect to annual plant growth rates, these exponents provide important boundary conditions with which to model forest nutrient cycling.
5

Patterns of the growth of soft-shell clam Mya arenaria L. (Bivalvia) in shallow water estuaries of the southern Baltic Sea

84%
Filippenko D., Naumenko E.
International Journal of Ecohydrology and Hydrobiology
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2014
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tom 14
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nr 2
6

Cranial ontogeny of Lutreolina crassicaudata (Didelphidae): a comparison with Didelphis albiventris

84%
Flores D. A., Giannini N. P., Abdala F.
Acta Theriologica
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2003
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tom 48
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nr 1
Metatherians experience the greatest developmental changes during extrauterine life. Following previous studies on Didelphis albiventris Lund, 1840, we examined the postweaning cranial allometry of size of the Neotropical marsupial Lutreolina cras- sicaudata (Desmerest, 1804). Our aim was to compare growth patterns of both species to identify traits particular to each species and traits common to both species. This may contribute toward identifying a common developmental plan for didelphids. We mea­sured 15 cranial variables in 32-43 specimens from just-weaned young to old adult. Total length of the skull was the estimator of overall size in least squares and reduced major axis regressions. The skull of Lutreolina crassicaudata grows at a rate slower than the overall change in size in its neurocranial components, palate, and postcanine rows, and it grows relatively faster in the rest of the splanchnocranium. This pattern closely resembles that of Didelphis albiventris, from which it differs mainly in the allometry of the muzzle. In both species, allometry explains most postweaning changes of the trophic apparatus on functional grounds, in relation to interspecific differences in diet. We hypothesize that most local allometric departures from a generalized didelphid plan would relate to main dietary trends.
7

Bacular variation and allometry in the western marten Martes caurina

84%
Miller E. H., Nagorsen D. W.
Acta Theriologica
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2008
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tom 53
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nr 2
Many sexually-selected structures are variable and positively allometric relative to body size. For the western martenMartes caurina Merriam, 1890 from Vancouver Island, British Columbia, we investigated variation in the baculum compared with other bones and allometry of bacular to body size. Carcass length did not differ, and humeral and mandibular lengths differed little (< 1 and 2%, respectively), between age groupings < 1 and ≥ 1 yr old. In contrast, bacular length increased by 16%, and thickness by 29% (mid shaft) and 86% (basal) between those groupings, and thickness and mass continued to grow after the second year of life. Controlling for body size, bacular size varied more than humeral or mandibular size (CV for linear variables ∼4–8% for baculum, ∼2% for humerus or mandible). Some positive static allometry of bacular size to body size was found, but correlations between bacular and body size were weak (r=0.3–0.4). So penile size as related to bacular size could be a reliable but imprecise quality indicator during copulation. Weak polygamy (serial promiscuity), complex copulatory mechanisms, and high energetic costs of reproduction, likely select for multiple cues in mate-choice by females, not just penile cues affected by bacular size or shape.
8
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Content available

Allometric growth in the frontals of the Mongolian theropod dinosaur Tarbosaurus bataar

67%
Yun C.-G., Peters G. F., Currie P. J.
Acta Palaeontologica Polonica
|
2022
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tom 67
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nr 3
9

The relative growth of walking legs of adult Chinese mitten crabs, Eriocheir sinensis in the Odra estuary (Poland). The major axis statistical modeling

67%
De Giosa M., Czerniejewski P.
Oceanological and Hydrobiological Studies
|
2011
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tom 40
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nr 3
10

Morphology and ecology in tintinnid ciliates of the marine plankton: correlates of lorica dimensions

67%
Dolan J. R.
Acta Protozoologica
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2010
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tom 49
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nr 3
235-244
11

Allometric analysis of cranial parameters of American mink, including bones of masticatory apparatus

67%
Jakubowski H., Komosa M., Frackowiak H.
Electronic Journal of Polish Agricultural Universities. Series Veterinary Medicine
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2008
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tom 11
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nr 3
12

Major axis approach to the statistical analysis of the relative growth of Chinese mitten crab (Eriocheir sinensis) in the Odra estuary (Poland)

67%
De Giosa M., Czerniejewski P.
Oceanological and Hydrobiological Studies
|
2011
|
tom 40
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nr 1
13
Artykuł dostępny w postaci pełnego tekstu - kliknij by otworzyć plik
Content available

Capybaras, size, shape, and time: A model kit

67%
Vucetich M. G., Deschamps C. M., Olivares A. I., Dozo M. T.
Acta Palaeontologica Polonica
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2005
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tom 50
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nr 2
The capybaras (Hydrochoeridae) are outstanding rodents for their large size and euhypsodont and multilaminated cheek teeth. Although today they are represented by a single species, it was generally thought that their past diversity was much higher, especially during the late Miocene–early Pliocene. Such diversity is here analyzed taking into account the ontogenetic variation of the p4–m3 in different populations. Numerous isolated teeth of different size found in the upper levels of the Puerto Madryn Formation (late Miocene, Peninsula Valdés, Argentina) were interpreted as members of an ontogenetic series of a new species here described, Cardiatherium patagonicum. They provided clues to evaluate ontogenetic variation and a new framework to analyze the family diversity. In this context, it is proposed that multiple species described from the Ituzaingó Formation (late Miocene, Entre Ríos, Argentina) based on lower teeth, may actually represent specimens of different stages of the ontogenetic trajectory of a single species. Likewise, we found that several nominal taxa from other localities were based on juvenile specimens. According to these results, the diversity of the Hydrochoeridae during the late Miocene and early Pliocene was drastically reduced. The validity of the subfamily Cardiatheriinae is debated. Finally, it is suggested that the whole family should be revised taking into account the ontogenetic variation.
14
Artykuł dostępny w postaci pełnego tekstu - kliknij by otworzyć plik
Content available

Morphological requirements in limulid and decapod gills: A case study in deducing the function of lamellipedian exopod lamellae

67%
Suzuki Y., Kondo A., Bergstrom J.
Acta Palaeontologica Polonica
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2008
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tom 53
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nr 2
According to one hypothesis, the exopods of extinct lamellipedian arthropods functioned as gills. To evaluate this hypothesis, the growth rates in Limulus polyphemus for total gill surface, average area per single gill lamella and number of gill lamellae are documented. The rates are compared with corresponding rates in decapod crustaceans in order to make deductions on morphological constraints in multi−foliated gills. The growth rates are given as allometric scaling exponents relative to the animal dry−body weight. The comparisons reveal that each allometric exponent is similar among examined species irrespective of differences in gill morphology or animal body plans. The numerical growth of lamellae obviously is much smaller than the growth of the total respiratory surface. To fulfill these trends in multi−foliated gills, the overall profile tends to become conical, with the result that the surface area is a couple of magnitudes larger at the base of the cone than at the tip. This geometrical shape appears to keep the numerical value of the total respiratory area (total lamellar surface) proportional to the cube of the total number of lamellae. The situation is entirely different in animals with lamellipedian exopods. In the latter, lamellae are slender structures carried in a straight row and, as exemplified by Naraoia, their increase in number during the growth is only half that required for the exopod lamellae to have functioned as an arthropod multi−foliated gill cone.
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