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1.
Zoolog Sci ; 36(6): 511-520, 2019 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-31833322

RESUMO

To gain a better understanding of the effect of reproductive modes and swimming ability on ostracod distribution, we visited 111 randomly selected aquatic sites in Kirsehir province. A total of 35 ostracods were newly reported for the area. The number of species with and without swimming setae was not statistically different, but numbers of sexual species was significantly lower than parthenogenetics. Species without setae did not show a significant difference between sexual and parthenogenetic forms. Numbers of species with (out) setae were not significant among different elevational ranges. Distribution of parthenogenetic species was common in all 11 habitat types when sexual species were only found from three different types located from 690 to ca. 1400 m of elevational ranges. Numbers of parthenogenetic species with or without setae did not show a difference among the ranges, but sexual species without setae exhibited wider distributional ranges (690-1289 m) than species with swimming setae (690-1089 m). Species' co-occurrence revealed two positive, five negative, and 44 random pairs of co-occurrences. Wards cluster analyses portrayed three main clustering groups. While group I includes parthenogenetic and sexual species, group II covers mostly parthenogenetic species with and without setae. Group III consists of species without setae. CCA results displayed three environmental variables (water temperature, pH and elevation) effective on species distribution. Species distributed in all elevational ranges tend to show lower optimum and wider ecological tolerances. Parthenogenetic species with swimming setae and with relatively higher tolerance ranges were dominant over sexual species. The present results suggest that swimming mode has a greater effect on species distribution among the habitats than reproductive modes.


Assuntos
Crustáceos/fisiologia , Ecossistema , Natação/fisiologia , Distribuição Animal , Animais , Reprodução/fisiologia , Especificidade da Espécie , Turquia
2.
Zootaxa ; 4277(2): 261-273, 2017 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-30308650

RESUMO

Lacrimacandona n. gen. with its type species Lacrimacandona wisei n. sp. from the San Marcos artesian well on the Texas State University campus (Hays County, Texas, USA) is proposed as a new genus of the subfamily Candoninae. The new species is sexually dimorphic, and so far no congeneric species have been found. The new genus has the following distinguishing characters: subtriangular carapace tapering posteriorly, uropod with a claw-like anterior seta and two short claws, one long "a" setae on male maxilliped, very large asymmetric clasping organs in males, unique shape and size of hemipenis, and unique occurrence of setae on segments.


Assuntos
Crustáceos , Distribuição Animal , Animais , Água Subterrânea , Masculino , Texas , Universidades
3.
Zootaxa ; 3937(3): 456-70, 2015 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-25947480

RESUMO

We describe a new species (Gomphocythere besni n. sp.) from the Tavas man-made pool in Besni town (Adiyaman, Turkey). The species has several differences from its congeners in furcal structures (forked organ, seta of caudal ramus), numbers of setae on maxillula and maxillular palp, particular ornamentation with up to eight fossae in each mesh of the reticulation and in the presence of two types of lateral pore-canals (single pore opening with a sensillum and sieve plates) on the carapace. The finding of the new species extends the known geographical distribution of the living forms of the genus further to the North. The new species was found from relatively cool (16.6 ºC) and medium oxygenated waters (7.36 mg/L) in a mixture of sand and gravel substrate. Details about its ecology and taxonomic status are also compared and discussed with other species of the same genus.


Assuntos
Crustáceos/classificação , Crustáceos/ultraestrutura , Distribuição Animal , Animais , Masculino , Especificidade da Espécie , Turquia
4.
High Alt Med Biol ; 13(2): 126-37, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22724616

RESUMO

We evaluated Rapoport's rule which states a negative correlation between species richness and altitude. To understand the relationship between altitude and reproductive modes (a/sexual) of non-marine ostracods, 166 aquatic bodies in Ordu region, Turkey were randomly sampled from July 11 to July 16, 2010. A total of 26 species of ostracods were found from 133 out of 166 sites. Except for one species (Heterocypris incongruens), the other 25 species were new reports for the region. Candona improvisa was also a new report for Turkish ostracod fauna. Three species (Psychrodromus olivaceus, H. incongruens, and C. neglecta) occurred most frequently as 43, 46, and 76 times, respectively. Canonical correspondence analyses exhibited two variables [Habitat type (p=0.014; F=2.171) and water temperature (p=0.018; F=2.248)] as having the most effect on species. Correlation of species' reproductive modes to those of environmental variables measured was not significant. UPGMA dendrogram displayed 15 most frequently occurring species into four clusters where most species (11) were asexual. Although a small group (asexual species without swimming setae) showed a tendency to habitat type and electrical conductivity, such variables are believed to play secondary role on species distribution. Highest species diversity (13 species) was observed at the range of 1200 and 1400 m (a.s.l.), where numbers of stations sampled was not the highest (22). Numbers of asexual species (19) were higher than the sexual (11) but there were no significant differences (p>0.05) between the frequencies of their occurrences at different altitudinal ranges. Accordingly, our findings do not support the Rapoport Rule. Results yield that reproductive modes of species (sexual and asexual) was not directly correlated to altitude or any environmental variables measured during this study. A better explanation of ostracod diversity appears to be suitability of habitats.


Assuntos
Altitude , Biodiversidade , Crustáceos/fisiologia , Reprodução , Animais , Geografia , Reprodução Assexuada , Especificidade da Espécie , Turquia
5.
J Hazard Mater ; 173(1-3): 123-9, 2010 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-19748176

RESUMO

The adsorption of copper ions on Spirulina platensis was studied as a function of contact time, initial metal ion concentration, and initial pH regimes. Characterization of this adsorbent was confirmed by FTIR spectrum. Modified Gompertz and Logistic models have not been previously applied for the adsorption of copper. Logistic was the best model to describe experimental kinetic data. This adsorption could be explained by the intra-particle diffusion, which was composed of more than one sorption processes. Langmuir, Freundlich, and Redlich-Peterson were fitted to equilibrium data models. According to values of error functions and correlation coefficient, the Langmuir and Redlich-Peterson models were more appropriate to describe the adsorption of copper ions on S. platensis. The monolayer maximum adsorption capacity of copper ions was determined as 67.93 mg g(-1). Results indicated that this adsorbent had a great potential for removing of copper as an eco-friendly process.


Assuntos
Cobre/química , Spirulina/química , Poluentes Químicos da Água/análise , Adsorção , Algoritmos , Biomassa , Previsões , Concentração de Íons de Hidrogênio , Cinética , Modelos Logísticos , Modelos Estatísticos , Soluções , Espectroscopia de Infravermelho com Transformada de Fourier , Termodinâmica , Água , Purificação da Água
6.
Bioresour Technol ; 100(14): 3625-9, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19329296

RESUMO

Batch cultivations were performed to evaluate the influence of phosphate concentrations (0.25, 0.5, 0.75, and 1.0 g L(-1)) for pH regimes (9.5, 10.0, and 10.5) on the biomass production by Spirulina platensis. The best condition for cell growth (3.099 g L(-1)) was found at 0.5 g L(-1) phosphate and pH value of 10.0. Cultivation time, phosphate, and pH caused to increase significantly (p<0.01) in biomass production by S. platensis. Lag time was observed up to 4 h. After then, biomass production increased sharply (p<0.01) from 0.020 g L(-1) to 2.063, 2.213, 1.532, and 0.797 g L(-1) at 0.25, 0.5, 0.75, and 1.0 g L(-1) phosphate values, respectively. Modified Gompertz model could be regarded as sufficient to describe the biomass production by S. platensis with high determination coefficients and low sum of square value indicated that. Biological parameters for biomass production were successfully predicted by modified Gompertz model.


Assuntos
Biomassa , Biotecnologia/métodos , Clorofila/química , Nitratos/metabolismo , Fosfatos/metabolismo , Spirulina/crescimento & desenvolvimento , Clorofila/metabolismo , Clorofila A , Concentração de Íons de Hidrogênio , Modelos Biológicos , Modelos Estatísticos , Fosfatos/química
7.
Bioresour Technol ; 100(5): 1847-51, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18993057

RESUMO

Effects of nitrate (2.0, 2.5, and 3.0 g L(-1)) and salt (0.5, 1.0, 1.5, 2.0 g L(-1)) concentrations on biomass production by Spirulinaplatensis was examined in the Schlösser medium. The highest (p<0.001) biomass yields and chlorophyll a content was observed at 2.5 g L(-1) nitrate and 1.5 g L(-1) NaCl as 3.495 g L(-1) and 29.92 mg L(-1), respectively. Increment rate of biomass production was especially found between 72 and 216 h. Modified Richards, Schnute, Logistic and Gompertz models was successfully predicted (r(2)>0.96 and RSS0.003) biomass production by S.platensis as function of nitrate and salt concentrations. Low residual sum of squares (RSS) and high regression coefficients (r(2)) indicated that used models were well fitted to the experiment data and it could be regarded as sufficient to describe biomass production of Spirulina sp. Biological variables i.e. production rate (micro) and lag time (lambda) for S.platensis ranged 0.012-0.034 h(-1) and 2.43-5.85 h, respectively from biomass production were successfully predicted by modified Logistic model according to low RSS and F-testing value.


Assuntos
Biotecnologia/métodos , Nitratos/metabolismo , Cloreto de Sódio/metabolismo , Spirulina/crescimento & desenvolvimento , Biomassa , Clorofila/metabolismo , Clorofila A , Modelos Biológicos , Análise de Regressão
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