Can large branchiopods shape microcrustacean communities in Mediterranean temporary wetlands?

2011 ◽  
Vol 62 (1) ◽  
pp. 46 ◽  
Author(s):  
Aline Waterkeyn ◽  
Patrick Grillas ◽  
Maria Anton-Pardo ◽  
Bram Vanschoenwinkel ◽  
Luc Brendonck
Keyword(s):  
Biotic Interactions ◽  
Resting Eggs ◽  
Salinity Range ◽  
Temporary Wetlands ◽  
Large Branchiopods ◽  
Top Predators ◽  
Triops Cancriformis ◽  
Wide Range ◽  
Negative Effect ◽  
Chirocephalus Diaphanus

It was recently suggested that large branchiopods may play a keystone role in temporary aquatic habitats. Using a microcosm experiment manipulating microcrustacean communities of Mediterranean temporary wetlands (Camargue, Southern France), we tested the following hypotheses: (i) large branchiopods (the notostracan Triops cancriformis and the anostracan Chirocephalus diaphanus) can limit microcrustacean densities through both competition and predation; (ii) notostracans create high suspended-matter concentrations through bioturbation, which can negatively impact microcrustaceans; and (iii) the outcome of these biotic interactions is more detrimental at high salinities. We found a strong predatory impact of T. cancriformis on active microcrustacean populations, but also on dormant populations through the consumption of resting eggs. They also preyed on anostracans and their conspecifics and can indirectly have a negative effect on microcrustaceans through bioturbation, probably by impeding filtering capacities. The presence of C. diaphanus also limited most microcrustacean groups, probably through competition and/or predation. We did not find a significant effect of the tested salinity range (0.5–2.5 g L–1) on the biotic interactions. Our study shows that large branchiopods can shape microcrustacean communities under a wide range of environmental conditions and confirms their potential for a keystone role, especially one of notostracans as top predators.

scholarly journals Isolation by sugar flotation has no direct effect on the hatching success of zooplankton resting eggs

2016 ◽  
Author(s):  
Dunja Lukic ◽  
Csaba F. Vad ◽  
Zsófia Horváth
Keyword(s):  
Hatching Success ◽  
Resting Eggs ◽  
Accurate Estimation ◽  
Temporary Waters ◽  
Large Branchiopods ◽  
Triops Cancriformis ◽  
Significant Difference ◽  
Flotation Method ◽  
Active Communities ◽  
Sugar Flotation

<p>Zooplankton in temporary waters produces resting stages to survive recurrent dry periods. Branchiopod crustaceans (i.e., cladocerans, large branchiopods) overcome these periods in the form of resting eggs buried in the sediment. Examining the diversity in the resting egg banks allows for a more accurate estimation of biodiversity of aquatic ecosystems than looking only at the active communities. The isolation of resting eggs from the sediment may be achieved by the sugar flotation method, which usually results in higher density and diversity than untreated samples (i.e., incubated in the sediment). We tested the effect of sugar isolation and centrifugation on the hatching success of resting eggs already isolated from sediment in order to reveal any direct effects on hatching success. We used four different branchiopod species, <em>Daphnia magna</em>, <em>Moina brachiata</em>, <em>Branchinecta orientalis</em>, and <em>Triops cancriformis</em>. Although we hypothesised that osmotic stress caused by sugar and centrifuging influence the hatching success either positively (e.g., faster activation as a response to osmotic changes) or negatively (destroyed by centrifugation), we found no significant difference either in the timing or rate of hatching between centrifuged and non-centrifuged eggs. Once the eggs are exposed to light and/or oxygen availability by being removed from the sediment, the centrifugation process does not have any additional effect on their hatching. Regardless of treatment, we found a significant difference in the hatching timing in the two major groups, with large branchiopods hatching earlier than cladocerans. We found that the sugar flotation method itself does not influence the hatching fraction of branchiopod resting eggs (implying no adverse effect on their viability) and its success in enhancing hatching can be attributed to its efficiency in removing eggs from the sediment.</p>

scholarly journals Cyst morphology of large branchiopod crustaceans (Anostraca, Notostraca, Laevicaudata, Spinicaudata) in western Poland

2016 ◽  
Vol 53 (2) ◽  
pp. 79-88 ◽  
Author(s):  
Michał Jan Czyż ◽  
Paweł Woliński ◽  
Bartłomiej Gołdyn
Keyword(s):  
Electron Microscope ◽  
Resting Eggs ◽  
Large Branchiopods ◽  
Triops Cancriformis ◽  
New Localities ◽  
Branchipus Schaefferi ◽  
Large Branchiopod ◽  
Scanning Electron ◽  
Cyst Morphology

AbstractThe morphology of resting eggs was studied in Polish populations of 7 large branchiopod species:Branchipus schaefferi,Chirocephalus shadini,Eubranchipus grubii(Anostraca),Lepidurus apus,Triops cancriformis(Notostraca),Lynceus brachyurus(Laevicaudata), andCyzicus tetracerus(Spinicaudata). Scanning electron microscope photographs for each species are also provided. In some species (especiallyE. grubii), the ornamentation and size of cysts from Polish populations significantly differ from literature data for populations from other parts of Europe. We also present a key to determination of the studied species based on cyst morphology and discuss whether those traits are useful in surveys of new localities of endangered large branchiopods.

Research on the Economic Organization Environmental Impact

2017 ◽  
Vol 68 (3) ◽  
pp. 599-601
Author(s):  
Dan Paul Stefanescu ◽  
Oana Roxana Chivu ◽  
Claudiu Babis ◽  
Augustin Semenescu ◽  
Alina Gligor
Keyword(s):  
Economic Activity ◽  
Economic Organization ◽  
Economic Activities ◽  
Environmental Implications ◽  
Minimal Impact ◽  
Wide Range ◽  
Material Environment ◽  
Negative Effect ◽  
Harmful Effects

Any economic activity carried out by an organization, can generate a wide range of environmental implications. Particularly important, must be considered the activities that have a significant negative effect on the environment, meaning those which pollute. Being known the harmful effects of pollution on the human health, the paper presents two models of utmost importance, one of the material environment-economy interactions balance and the other of the material flows between environmental factors and socio-economic activities. The study of these models enable specific conditions that must be satisfied for the economic processes friendly coexist to the environment for long term, meaning to have a minimal impact in that the residues resulting from the economic activity of the organization to be as less harmful to the environment.

Associated microflora of medicinal ferns: biotechnological potentials and possible applications

2016 ◽  
Vol 5 (03) ◽  
pp. 4927 ◽  
Author(s):  
Shubhi Srivastava ◽  
Paul A. K.
Keyword(s):  
Secondary Metabolites ◽  
Growth Promotion ◽  
Biological Activities ◽  
Hydrolytic Enzymes ◽  
In Vitro Production ◽  
Wide Range ◽  
Negative Effect ◽  
Bacteria And Fungi

Plant associated microorganisms that colonize the upper and internal tissues of roots, stems, leaves and flowers of healthy plants without causing any visible harmful or negative effect on their host. Diversity of microbes have been extensively studied in a wide variety of vascular plants and shown to promote plant establishment, growth and development and impart resistance against pathogenic infections. Ferns and their associated microbes have also attracted the attention of the scientific communities as sources of novel bioactive secondary metabolites. The ferns and fern alleles, which are well adapted to diverse environmental conditions, produce various secondary metabolites such as flavonoids, steroids, alkaloids, phenols, triterpenoid compounds, variety of amino acids and fatty acids along with some unique metabolites as adaptive features and are traditionally used for human health and medicine. In this review attention has been focused to prepare a comprehensive account of ethnomedicinal properties of some common ferns and fern alleles. Association of bacteria and fungi in the rhizosphere, phyllosphere and endosphere of these medicinally important ferns and their interaction with the host plant has been emphasized keeping in view their possible biotechnological potentials and applications. The processes of host-microbe interaction leading to establishment and colonization of endophytes are less-well characterized in comparison to rhizospheric and phyllospheric microflora. However, the endophytes are possessing same characteristics as rhizospheric and phyllospheric to stimulate the in vivo synthesis as well as in vitro production of secondary metabolites with a wide range of biological activities such as plant growth promotion by production of phytohormones, siderophores, fixation of nitrogen, and phosphate solubilization. Synthesis of pharmaceutically important products such as anticancer compounds, antioxidants, antimicrobials, antiviral substances and hydrolytic enzymes could be some of the promising areas of research and commercial exploitation.

scholarly journals A Review of Recently Discovered Remains of the Pleistocene Branchiopods (Anostraca, Notostraca) from NE Siberia and Arctic Canada

Water ◽  
2021 ◽  
Vol 13 (3) ◽  
pp. 280
Author(s):  
D. Christopher Rogers ◽  
Anton A. Zharov ◽  
Anna N. Neretina ◽  
Svetlana A. Kuzmina ◽  
Alexey A. Kotov
Keyword(s):  
Western North America ◽  
Temporary Wetlands ◽  
Indicator Organisms ◽  
Aquatic Habitats ◽  
Eastern Asia ◽  
Large Mammal ◽  
Large Branchiopods ◽  
North Eastern ◽  
North Western ◽  
Large Branchiopod

In this study, we examine, identify, and discuss fossil remains of large branchiopod crustaceans collected from six sites across the Beringian region (north-eastern Asia and north-western North America). Eggs and mandibles from Anostraca and Notostraca, as well as a notostracan telson fragment and a possible notostracan second maxilla, were collected from both paleosediment samples and also from large mammal hair. The remains of large branchiopods and other species that are limited to seasonally astatic aquatic habitats (temporary wetlands) could be useful indicator organisms of paleoecological conditions. Different recent large branchiopod species have very different ecological preferences, with each species limited to specific geochemical component tolerance ranges regarding various salinity, cation, and gypsum concentrations. Our purpose is to bring the potential usefulness of these common fossil organisms to the attention of paleoecologists.

Habitats for large branchiopods in the agricultural landscape of the Mureş Floodplain Natural Park: how long will they last?

Crustaceana ◽  
2021 ◽  
Vol 94 (7) ◽  
pp. 775-795
Author(s):  
Alfred-Ştefan Cicort-Lucaciu ◽  
Gabriel-Lucian Herlo
Keyword(s):  
Agricultural Landscape ◽  
Habitat Type ◽  
Natural Habitats ◽  
Natural Landscape ◽  
Large Branchiopods ◽  
Natural Park ◽  
Black Spots ◽  
Chirocephalus Diaphanus ◽  
Floodplain Area ◽  
Large Branchiopod

Abstract In the last two hundred years, the Mureş River Floodplain has suffered major changes caused by dike constructions, meander cutting, and by the transformation of the natural landscape into an agricultural one. In this environmental context, we wanted to find out the degree to which large branchiopod species still survive in the Mureş Floodplain area. Every stagnant aquatic habitat encountered in 2019 in the Mureş Floodplain Natural Park was sampled. For the habitats where more species co-occur, urgent preservation actions must be taken. Most of the species prefer open habitats and have survived in the wheel ruts on agricultural lands. In the absence of natural habitats, the importance of this habitat type becomes a major one. The forest advantages species related to shady habitats, such as Chirocephalus diaphanus. We have found several individuals in the park that showed black spots on their bodies, characteristic of the black disease of fairy shrimp. The presence of the disease only in the populations from wheel ruts suggests that vehicles which make these ruts, could be the carriers of the disease.

scholarly journals The Study of Internet Use and Academic Achievement of Elementary Students in Bangkok

2016 ◽  
Vol 6 (2) ◽  
pp. 71
Author(s):  
Aouyporn Suphasawat ◽  
Sirichai Hongsanguansri ◽  
Patcharin Seree ◽  
Ouaychai Rotjananirunkit
Keyword(s):  
Academic Achievement ◽  
Social Media ◽  
Math Achievement ◽  
Achievement Test ◽  
Internet Usage ◽  
School Students ◽  
Wide Range Achievement Test ◽  
Multi Stage ◽  
Wide Range ◽  
Negative Effect

<p>The purpose of this study is to investigate the relationship between internet usage behavior and academic achievement among elementary school students from grade 4-6 in Bangkok. The researcher employed Multi-stage Sampling to recruit 297 samples. The data was gathered via the following tests: 1) Intelligence tests, namely Colored Progressive Matrices (CPM) for students aged 5-11 year old or Standard Progressive Matrices (SPM) for 12 year old and above, and 2) Academic achievement test, namely Wide Range Achievement Test Thai Edition: WRAT-Thai. The findings revealed that time spent on the internet is negatively correlated to student’s reading achievement (r = -.24, p &lt; .001), spelling achievement (r = -.26, p &lt; .001), and math achievement (r = -.20, p = .001). More surprisingly, academic related internet usage was also found to be negatively correlated to math achievement (r = -.20, p &lt; 0.05). Meanwhile, internet usage for social media has a correlation with academic achievement in math and reading, (r = -.20, p = .001) and (r = -.13, p &lt; .05), respectively. Moreover, internet usage for entertainment was found to have a negative correlation with academic achievement in reading, spelling and math, (r = -.25, p &lt; .001), (r = -.27, p &lt; .001) and (r = -.21, p &lt; .001), respectively. Internet usage for online business, however, yielded no correlation to academic achievement. The study concluded that daily internet usage does have an effect on academic achievement in math. Moreover, when used for entertainment and social media, internet usage can pose a negative effect on academic achievement in reading and writing.</p>

NON-CLADOCERAN BRANCHIOPOD CRUSTACEANS FROM SOUTHWEST PORTUGAL. I. OCCURRENCE NOTES

Crustaceana ◽  
1999 ◽  
Vol 72 (6) ◽  
pp. 591-602 ◽  
Author(s):  
Luis Cancela Da Fonseca ◽  
Margarida MaChado ◽  
Margarida Cristo
Keyword(s):  
New Records ◽  
Freshwater Ponds ◽  
Triops Cancriformis ◽  
Chirocephalus Diaphanus ◽  
First Time ◽  
Sw Portugal

AbstractThe presence of non-cladoceran branchiopods was detected in only 16 out of 83 temporary freshwater ponds of SW Portugal, which were recently sampled by the authors and other researchers. Two anostracans, Branchipus cortesi and Chirocephalus diaphanus; two spinicaudatans, Cyzicus grubei and Maghrebestheria maroccana; and one notostracan, Triops cancriformis mauritanicus, were identified. All taxa are new records locally, and all but C. grubei and T. c. mauritanicus are reported for the first time from Portugal. La presence de Branchiopodes non Cladoceres a ete detectee dans 16 seulement des 83 mares temporaires d'eau douce du SO du Portugal, qui ont ete recemment echantillonnees par les auteurs et d'autres chercheurs. Deux Anostraces, Branchipus cortesi et Chirocephalus diaphanus, deux Spinicaudata, Cyzicus grubei et Maghrebestheria maroccana, et un Notostrace, Triops cancriformis mauritanicus, ont ete identifies. Tous les taxa sont nouveaux pour la faune locale et tous, sauf C. grubei et T. c. mauritanicus, sont signales pour la premiere fois du Portugal.

scholarly journals A Possible Role of Allatostatin C in Inhibiting Ecdysone Biosynthesis Revealed in the Mud Crab Scylla paramamosain

2021 ◽  
Vol 8 ◽  
Author(s):  
An Liu ◽  
Wenyuan Shi ◽  
Dongdong Lin ◽  
Haihui Ye
Keyword(s):  
Scylla Paramamosain ◽  
Dependent Manner ◽  
Mud Crab ◽  
Methyl Farnesoate ◽  
Independent Manner ◽  
Wide Range ◽  
Negative Effect

C-type allatostatins (C-type ASTs) are a family of structurally related neuropeptides found in a wide range of insects and crustaceans. To date, the C-type allatostatin receptor in crustaceans has not been deorphaned, and little is known about its physiological functions. In this study, we aimed to functionally define a C-type ASTs receptor in the mud crab, Scylla paramamosian. We showed that C-type ASTs receptor can be activated by ScypaAST-C peptide in a dose-independent manner and by ScypaAST-CCC peptide in a dose-dependent manner with an IC50 value of 6.683 nM. Subsequently, in vivo and in vitro experiments were performed to investigate the potential roles of ScypaAST-C and ScypaAST-CCC peptides in the regulation of ecdysone (20E) and methyl farnesoate (MF) biosynthesis. The results indicated that ScypaAST-C inhibited biosynthesis of 20E in the Y-organ, whereas ScypaAST-CCC had no effect on the production of 20E. In addition, qRT-PCR showed that both ScypaAST-C and ScypaAST-CCC significantly decreased the level of expression of the MF biosynthetic enzyme gene in the mandibular organ, suggesting that the two neuropeptides have a negative effect on the MF biosynthesis in mandibular organs. In conclusion, this study provided new insight into the physiological roles of AST-C in inhibiting ecdysone biosynthesis. Furthermore, it was revealed that AST-C family peptides might inhibit MF biosynthesis in crustaceans.

scholarly journals Assortative Mating, Income Inequality, and Place

2021 ◽  
Author(s):  
◽  
Avril Macfarlane
Keyword(s):  
Income Inequality ◽  
Assortative Mating ◽  
Household Income ◽  
European Social Survey ◽  
Highly Educated ◽  
Wide Range ◽  
Negative Effect ◽  
Educational Assortative Mating ◽  
Highly Correlated ◽  
The Relationship

<p>There is a growing concern internationally about levels of income inequality, and the negative effect this has on the functioning of societies both in terms of productivity and social harmony. An unexpected contributor to inequality is assortative mating - the phenomenon of “like marrying like”. Educational attainment is highly correlated with income; when two highly educated people partner and form a household they are more likely to appear at the top of the household income distribution, while couples with only primary or incomplete secondary education appear at the bottom. Therefore the greater the propensity to mate assortatively the more unequal the distribution of household income becomes.   I ask two questions of the relationship between educational assortative mating and household income inequality. Firstly, how do countries (in Europe) differ in their degree of educational assortative mating? Secondly, what is the evidence that such differences are reflected in indicators of household income inequality?   My study differs from the prevailing approaches to this question by taking a geographical approach. Instead of comparing a single country over time and monitoring the correspondence between assortative mating and income inequality, I compare a wide range of countries, using a uniform instrument, at one point in time. In order to do so I draw on the unit records of 29 countries from the European Social Survey administered in 2012.   From these unit record data I have been able to identify two important patterns. Firstly, there is a clear presence of educational assortative mating in each country. However, the degree differs and it does so primarily as a reflection of the overall level of education in the country. Rising levels of education lower the returns for education, in turn making assortative mating comparatively less attractive. As a result, the level of assortative mating, compared to what would be expected under random conditions, is lower in highly educated nations. The lowered level of assortative mating in highly educated nations reduces the barriers to social mobility through marriage for those without university educations. Consequently, household income inequality is seen to be intrinsically related to assortative mating, although the outcomes can be mitigated by redistribution policies.</p>

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