Morphological variability of new chrysophyte stomatocyst forming a single-cyst assemblage in a low-conductivity tropical lake in the Guineo-Congolian rainforest

Phytotaxa ◽  
2014 ◽  
Vol 174 (5) ◽  
pp. 261 ◽  
Author(s):  
Jolanta Piątek ◽  
Marcin Piątek
Keyword(s):  
Shallow Lake ◽  
Surface Sediments ◽  
Sampling Site ◽  
Morphological Variability ◽  
Living Cells ◽  
Similar Data ◽  
Ecological Information ◽  
Single Cyst ◽  
The Third ◽  
Eastern Cameroon

Morphological variation of the chrysophyte stomatocyst found in surface sediments of a small, shallow lake in the Guineo-Congolian rainforest in eastern Cameroon, is described, illustrated and discussed. Neither living cells nor scales of chrysophytes were observed in the lake. The stomatocyst cannot be assigned to any known cyst and is described as new to science (stomatocyst #49) using International Statospore Working Group (ISWG) guidelines. This is the third report of stomatocysts in Africa, and the second from the tropical part of this continent. Some basic ecological information on the sampling site is provided and compared with similar data from other sampling sites of chrysophytes in Africa.

scholarly journals Dynamics of phytoplankton pigments in water and surface sediments of a large shallow lake

2011 ◽  
Vol 60 (2) ◽  
pp. 91 ◽  
Author(s):  
R Freiberg ◽  
M Nõmm ◽  
I Tõnno ◽  
T Alliksaar ◽  
T Nõges ◽  
...  
Keyword(s):  
Shallow Lake ◽  
Surface Sediments ◽  
Phytoplankton Pigments ◽  
Large Shallow Lake

Application the Grey Neural Network to Evaluate the Water Quality of the Yangtze Estuary Wetland

2014 ◽  
Vol 971-973 ◽  
pp. 2180-2185
Author(s):  
Sheng Long Yang
Keyword(s):  
Neural Network ◽  
Water Quality ◽  
Sea Water ◽  
Comprehensive Evaluation ◽  
Sampling Site ◽  
Predictive Ability ◽  
Yangtze Estuary ◽  
Similar Data ◽  
Data Set

Based on the Grey neural network, combine with the sampling data from Yangtze estuary wetland which measured in fifteen sampling site in raising tide and falling tide in May 2010 to intelligent comprehensive evaluation the sea water quality of Yangtze estuary wetland. The results showed that the sea water quality of sampling data wereⅠ.The precision of training and testing data set showed the Grey neural network had good generalization capacity, with good fitting precision and strongly predictive ability. It can be used to similar data set calculation.

scholarly journals Seasonal dynamics of epilithic diatom community from the Vrla River (Southeastern Serbia)

2021 ◽  
pp. 109-122
Author(s):  
Olga Jakovljević ◽  
Slađana Popović ◽  
Ivana Živić ◽  
Katarina Stojanović ◽  
Jelena Krizmanić
Keyword(s):  
Seasonal Dynamics ◽  
Sampling Site ◽  
Winter Period ◽  
Diatom Community ◽  
The Third ◽  
Four Seasons ◽  
Seasonal Analysis ◽  
The Relationship ◽  
Epilithic Diatom ◽  
Southeastern Serbia

Seasonal analysis of epilithic diatom community from the Vrla River was performed in four seasons a year (six times) at six sampling sites. Between the second (VR2) and the third sampling site (VR3) was located a trout fish farm. The highest number of diatom taxa was recorded in spring (149) and the lowest in autumn (93). The number of taxa that were found to be dominant during all four seasons was twenty-four. The relationship between 45 the best-fitted diatom taxa, which showed conspicuous seasonal dynamics, and seasons in which these taxa were recorded was illustrated using canonical correspondence analysis (CCA). The large number of taxa was identified in all four seasons or in winter period only. Few taxa were present only in spring and summer.

scholarly journals Morphological variability of Juniperus phoenicea (Cupressaceae) from three distant localities on Iberian Peninsula

2011 ◽  
Vol 72 (1) ◽  
pp. 71-78 ◽  
Author(s):  
Małgorzata Mazur ◽  
Krystyna Boratyńska ◽  
Katarzyna Marcysiak ◽  
Daniel Gómez ◽  
Dominik Tomaszewski ◽  
...  
Keyword(s):  
Genetic Differentiation ◽  
Iberian Peninsula ◽  
Morphological Variability ◽  
Biometrical Analysis ◽  
The Third ◽  
Juniperus Phoenicea

<p>The aim of the present study was biometrical comparison of three Iberian populations of <em>Juniperus phoenicea</em>, represented by the subsp. <em>turbinata </em>and subsp. <em>phoenicea</em>. Eight features of the cones and seeds, two of the shoots and leaves were studied.</p><p>The biometrical analysis of three distant populations of <em>J. phoenicea </em>shows great taxonomic distances among them. Two of them, representatives of <em>J. phoenicea</em> subsp. <em>turbinata</em>, are closer related each other than to the third, which represents <em>J. phoenicea</em> subsp. <em>phoenicea</em>. These results confirm the genetic differentiation of the taxons and also the biochemical and morphologic division of them. Nevertheless, the distances between particular populations are so great that more resemble the distances between species than between subspecies.</p>

THE CHIRONOMIDS (DIPTERA: CHIRONOMIDAE) OF SHALLOW LAKES OF THE HUMID PAMPA REGION, ARGENTINA: AN APPROACH TO PALEOPRODUCTIVITY RECONSTRUCTION

Palaios ◽  
2020 ◽  
Vol 35 (4) ◽  
pp. 191-200
Author(s):  
FERNANDA MONTES DE OCA ◽  
MARCELA S. TONELLO ◽  
JULIETA MASSAFERRO ◽  
M. SOFIA PLASTANI ◽  
CECILIA LAPRIDA
Keyword(s):  
Shallow Lakes ◽  
Aquatic Ecosystems ◽  
Trophic Status ◽  
Surface Sediments ◽  
Lake Productivity ◽  
Rainfall Gradient ◽  
Inference Models ◽  
Ecological Information ◽  
Pampa Region ◽  
Pampean Shallow Lakes

ABSTRACT The Humid Pampa, center-east of Argentina, is the most important socio-economical area of the country. Several shallow lakes have been the focus of many studies due to the significant changes in their trophic status related to human activities and to global warming recorded since the beginning of the twentieth century. Although chironomids have been used extensively in paleoclimatic and paleoenvironmental research, they are rarely used for paleoenvironmental reconstructions of the Pampean shallow lakes. The aim of this paper is to contribute to the knowledge of the chironmids' community composition and distribution in the Pampa region, and to relate their distribution to selected climatic and limnological variables. The ultimate goal is to retrieve new ecological information for future paleoenvironmental and paleoclimate reconstructions by using chironomid-based inference models. In this study, chironomids head capsules were collected from surface sediments from 17 shallow lakes of the Humid Pampa. Our analyses indicate that the chironomid assemblages reflect the decreasing NE-SW rainfall gradient of the region as well as the land use intensity, which in turn affects the aquatic ecosystems, in terms of lake productivity. Some chironomids are associated with brackish conditions (e.g., Chironomus, Ablabesmyia, Tanytarsini D2). Additionally the occurrence of assemblages of detritivore taxa such as Goeldochironomus, Chironomus, Polypedilum, and Dicrotendipes reflect the natural eutrophic state of Pampean shallow lakes, whereas assemblages mostly dominated by Coelotanypus, Procladius, and Chironomus are indicative of hypertrophic conditions, which are usually the result of human activity. This is the first study of chironomids from surface sediments from the central temperate plains of Argentina, and our records extend the ecological information of the Diptera in temperate areas. Although more studies are necessary to fully understand the main factors determining the chironomid fauna distribution in the Pampa region, we conclude that chironomids are potentially good proxies for paleoproductivity and salinity reconstructions of Pampean shallow lakes.

Explaining the Religious Basis of the Canadian Partisan Identity: Success on the Third Try

1974 ◽  
Vol 7 (3) ◽  
pp. 560-563 ◽  
Author(s):  
William P. Irvine
Keyword(s):  
Cultural Differences ◽  
Party Identification ◽  
Similar Data ◽  
Voting Behaviour ◽  
The Third ◽  
Percentage Difference ◽  
Current Concerns ◽  
Phi Coefficient ◽  
Roman Catholics ◽  
History Books

The various subtables of Table i, or some variant of them, must be familiar to every teacher and to every student of Canadian voting behaviour. While most of our history books, and certainly all of our current concerns, focus on cultural differences in Canada, all our voting and party identification data suggest that the primary line of political division is between Roman Catholics and non-Catholics. The leftmost tables in the two rows of Table i indicate that religious differences are approximately three times as strong as ethnic ones, regardless of the index chosen. The percentage difference in Liberal identifiers is 20 across religious categories, but only 6 across the ethnic ones; the phi coefficient is.21 as compared to.06, while Yule's Q is.42 as opposed to.13. Nor is this simply an artifact. The same finding shows up for vote as for party identification, for a linguistic dichotomy as for an ethnicity dichotomy, and for undichotomized as for dichotomized variables. Similarly, the religious dichotomy need not be imposed, but emerges quite freely when similar data are analysed with the aid program. Indeed, one need not depend on using dichotomies at all, though the analysis becomes more complex. In each case, however, the basic generalization holds.

scholarly journals Importance of the macrofauna for the feeding of young fish species from infralittoral of Arrozal: Cananeia lagoon estuarine region (25º02'S-47º56'W) - Brazil

1993 ◽  
Vol 41 (1-2) ◽  
pp. 39-52 ◽  
Author(s):  
Yoko Wakabara ◽  
Airton S. Tararam ◽  
Maurea N. Flynn
Keyword(s):  
Seasonal Variation ◽  
Fish Species ◽  
Food Source ◽  
Sampling Site ◽  
The Other ◽  
Nursery Ground ◽  
Young Fish ◽  
The Third ◽  
Balanced Diet ◽  
Estuarine Region

The aim of this study was to establish the importance of the macrofauna as food for young fish species that inhabit the infralittoral adjacent to the lower marsh. The sampling site is located at Arrozal, Cananéia lagoon estuarine region (25º02'S and 47º56'W) and the collectings were realized monthly, during a year. The results suggest that the studied area could be considered as a nursery ground for young fish species. The local macrofauna is composed mainly by several groups of crustaceans and has a marked temporal variation. Mysids were dominant in Spring, copepods in Summer, mysids and bivalves were co-dominants in the Autumn and amphipods in Winter. Mysids, copepods, ostracods, tan aids and other epifaunal crustaceans were more consumed than other items. According to the trophic habits, the twelve fish species could be divided into three groups: the first and the third as mysids and copepods eaters respectively, and the second group with a balanced diet reflecting more than the other groups the seasonal variation of the macrofauna collected by the dredge. Benthonic and benthopelagic organisms were considered the major food source, being consumed by 75% of the analysed fish species, in Cananéia infralittoral.

scholarly journals Synthetic and Bio-Derived Surfactants Versus Microbial Biosurfactants in the Cosmetic Industry: An Overview

2021 ◽  
Vol 22 (5) ◽  
pp. 2371
Author(s):  
Ana B. Moldes ◽  
Lorena Rodríguez-López ◽  
Myriam Rincón-Fontán ◽  
Alejandro López-Prieto ◽  
Xanel Vecino ◽  
...  
Keyword(s):  
Cost Effective ◽  
Living Cells ◽  
Personal Care ◽  
Renewable Sources ◽  
The Third ◽  
Cosmetic Industry ◽  
Pharmaceutical Industries ◽  
Natural Components ◽  
Second Category ◽  
Synthetic Surfactants

This article includes an updated review of the classification, uses and side effects of surfactants for their application in the cosmetic, personal care and pharmaceutical industries. Based on their origin and composition, surfactants can be divided into three different categories: (i) synthetic surfactants; (ii) bio-based surfactants; and (iii) microbial biosurfactants. The first group is the most widespread and cost-effective. It is composed of surfactants, which are synthetically produced, using non-renewable sources, with a final structure that is different from the natural components of living cells. The second category comprises surfactants of intermediate biocompatibility, usually produced by chemical synthesis but integrating fats, sugars or amino acids obtained from renewable sources into their structure. Finally, the third group of surfactants, designated as microbial biosurfactants, are considered the most biocompatible and eco-friendly, as they are produced by living cells, mostly bacteria and yeasts, without the intermediation of organic synthesis. Based on the information included in this review it would be interesting for cosmetic, personal care and pharmaceutical industries to consider microbial biosurfactants as a group apart from surfactants, needing specific regulations, as they are less toxic and more biocompatible than chemical surfactants having formulations that are more biocompatible and greener.

Temporal changes in foraminiferal distributions in Miramichi River estuary, New Brunswick

1977 ◽  
Vol 14 (7) ◽  
pp. 1566-1587 ◽  
Author(s):  
David B. Scott ◽  
Franco S. Medioli ◽  
Charles T. Schafer
Keyword(s):  
Cluster Analysis ◽  
New Brunswick ◽  
Surface Sediments ◽  
River Estuary ◽  
Temporal Changes ◽  
Similar Data ◽  
The Past ◽  
Circulation Patterns

Distribution of foraminifera from surface sediments collected during September 1975 and February 1976 in Miramichi estuary are described and compared to similar data reported previously from the same estuary. Three major assemblage zones presently occupy the estuary: the river, transitional, and open bay assemblage zones. Only two assemblage zones were observed in earlier studies: river and open bay. Sedimentological and geomorphological evidence suggests that circulation patterns in the estuary have changed sufficiently in the past decade to allow the transition assemblage to replace the open bay in large parts of the estuary.A comparison is made between the distributions obtained using a cluster analysis and those obtained using a direct, intuitive approach. The two methods yield almost identical results in this study and the cluster analysis should be a valuable tool when large amounts of data must be interpreted.Seasonal observations were limited; however, no major shifts of faunal zones were detected from September to February. One species, Protelphidium orbiculare, appears to be more common in the warmer months and may require relatively warm temperatures to reproduce.A new complementary classification of estuaries based on circulation detected by foraminiferal assemblages is proposed.

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