2018 ◽  
Vol 69 (3) ◽  
pp. 357
Author(s):  
F. H. Portella Corrêa de Oliveira ◽  
A. N. Moura ◽  
Ê. W. Dantas

The present study demonstrates the effects of abiotic variables on phytoplankton in two different tropical climates. Samples were taken from tropical reservoirs, including six from a tropical climate (As) and five from a semi-arid climate (BSh). Phytoplankton samples were identified, biomass was quantified and climatic and physicochemical variables were evaluated. Canonical analyses were performed in order to observe the effects of abiotic variables on phytoplankton. In both As and BSh ecosystems, the effects of the physicochemical variables were significant, but the synergistic effects between variables and climatic conditions were more pronounced in BSh. Micronutrients had a significant role in structuring the phytoplankton community in both As and BSh. In As, Cylindrospermopsis raciborskii occurred in the presence of lower concentrations of zinc and copper, whereas in BSh this species was present in the presence of higher concentrations of zinc. In the As climate, Geitlerinema amphibium, Cyclotella meneghiniana, Planktothrix agardhii and Microcystis aeruginosa were associated with higher sodium concentrations in the water, whereas in the BSh climate these species experienced lower rainfall. The findings of the present study show that climate determines the effects of abiotic variables on the phytoplankton community in both an independent and synergistic manner. In the present study, phytoplankton in tropical and semi-arid reservoirs is mostly regulated by nutrients, the effects of which vary according to climate.


1973 ◽  
Vol 51 (2) ◽  
pp. 437-450 ◽  
Author(s):  
B. R. Baum ◽  
Judy N. Findlay

Representative Canadian herbarium material of Danthonia was studied morphologically and micromorphologically. Characters used by previous authors were reexamined. Among the new characters studied the lodicule patterns were found to be very useful for discrimination. Canonical analyses were performed excluding input of lodicule patterns, but with the incorporation of various other lodicule attributes. As a result, five species are recognized for Canada; a key and a map of distribution are given. An additional canonical analysis with the inclusion of latitude and longitude added as input has shown that the geographical factor is insignificant.


2019 ◽  
Vol 70 (11) ◽  
pp. 1576
Author(s):  
F. H. P. C. de Oliveira ◽  
A. N. Moura ◽  
Ê. W. Dantas

This study reports the effects of the El Niño event of 2015–16 on abiotic and biotic variables in tropical reservoirs in semi-arid and wet regions. Samples were collected in control years (2014) and during the El Niño event (2015–16). Phytoplankton was identified and its biomass quantified. Physicochemical and climatic variables were evaluated. Canonical analyses were performed to determine the effects of abiotic variables on phytoplankton. In semi-arid ecosystems, there was a decrease in diversity during the El Niño event, as well as an increase in the relative biomass of centric diatoms and a decrease in filamentous cyanobacteria. In wet ecosystems, changes in the community were not observed during the El Niño event. The synergistic contribution between physiochemical and climatic variables was most pronounced during the El Niño event in all ecosystems. Filamentous cyanobacteria were associated with the control year and favoured by higher pH values and sulfate concentrations. Centric diatoms were related to higher air temperatures and lower sulfate concentrations during the El Niño event. El Niño caused morphofunctional modifications to the phytoplankton in a distinct way in semi-arid and wet ecosystems. We show that in semi-arid reservoirs the El Niño event decreased the relative biomass of filamentous cyanobacteria and favoured central diatoms because of changes to sulfate concentrations.


2009 ◽  
Vol 37 (4) ◽  
pp. 433-440 ◽  
Author(s):  
Malgorzata Sobol-Kwapinska

The relationships between forms of present time orientation (active concentration, hedonism, and fatalism) and satisfaction with life were examined. Data from 320 participants on time orientation measures and two satisfaction with life measures were analyzed using regression and canonical analyses. Unlike hedonism and fatalism, active present time orientation was associated with greater satisfaction with life and with more effective achievement of goals.


1997 ◽  
Vol 54 (8) ◽  
pp. 1873-1882 ◽  
Author(s):  
J R King ◽  
B J Shuter ◽  
A P Zimmerman

The 37-year record (1955-1992) of water temperature profiles and corresponding meteorology for South Bay (Lake Huron) provide an extensive empirical data set for the study of climate variability and corresponding alterations in lake thermal structure. Thermoclines became shallower over this period and epilimnetic temperatures increased. Canonical analyses correlated warm May-July air temperatures and high July-August solar radiation with warmer epilimnia, larger thermal gradients across the thermocline, and shallower thermoclines. Multivariate canonical scores indicate that these thermal responses have increased in parallel with the recent warming trend since the mid-1960s. Anomalous multivariate scores correspond to El Niño events, and an extreme low score corresponds to the Mount Pinatubo cooling effect of 1992.


1978 ◽  
Vol 56 (4) ◽  
pp. 374-385 ◽  
Author(s):  
Bernard R. Baum

Synopses of genera of Triticeae (including Elymus trinii which is not classified within any genus here) were elaborated and are here documented. A generic classificatory key together with four auxiliary keys are also provided: these are not analytical keys normally found in most treatments whose purpose is to identify every case to taxon. The synopses and keys were generated by computer using Pankhurst's program for generating diagnostic keys. Canonical analyses were performed on the six groupings obtained previously from a numerical taxonomic classification of the genera of this tribe. Canonical loadings, to be used for placement of the OTUs and graphic separation of the groupings, are provided. This paper does not treat the multitude of natural and artificial hybrids.


1977 ◽  
Vol 40 (3) ◽  
pp. 867-874
Author(s):  
William O. Bearden ◽  
Richard M. Durand

Evaluative beliefs underlying attitudes toward brands and demographic measures for a panel of 172 respondents were included as sets of variables in four canonical analyses, two brands in each of two product categories. The resulting canonical functions tentatively support the combination of consumers' beliefs about product attributes and the demographic characteristics of those consumers as a means of suggesting both specific segments of consumers and the nature of the belief structure within those segments. Given this type of information, the marketing manager can more effectively formulate specific aspects of marketing strategies for each relevant segment.


1996 ◽  
Vol 10 (3) ◽  
pp. 278-291 ◽  
Author(s):  
Alain Ferrand ◽  
Monique Pagès

This study is part of a larger investigation concerned with a methodology to evaluate the effectiveness of image sponsoring. The notion of image, which is equivalent to the idea of social representation from social psychology, is central to this series of studies. This study was concerned with the similarities and dissimilarities in the images or social representations of the Lyon's Tennis Grand Prix, France (GPTL) and Perrier, a seller of mineral water. In the first phase, a convenience sample of 80 subjects was presented with a list of 300 adjectives and requested to identify those adjectives that described the tennis event and Perrier, Frequency analyses of these responses showed that 23 adjectives were most often cited as representative of the tennis event, while 16 were cited as representative of Perrier. These items were used in the construction of a semantic differential scale, which was administered to 162 randomly selected subjects who were familiar with both the tennis event and Perrier. Canonical analyses showed that the GPTL and Perrier shared the images of (a) being highly popular and entertaining and (b) being dynamic and successful, but distracting. The results also showed that the GPTL had the images of (a) a distinguished, as opposed to a commercial, enterprise and (b) popular because of its arousal value. Perrier's images dimension was considered to be natural and young as opposed to appreciated. The practical implications of the results are discussed.


1985 ◽  
Vol 33 (3) ◽  
pp. 363 ◽  
Author(s):  
AE Newsome ◽  
LK Corbett

Dingoes Canis familiaris dingo, dogs C.J: familiaris, and their hybrids were classified on skull morphology as the following percentages in remote, inland Australia: 97.5,O.1 and 2.4; and in settled south-eastern Australia as 55.3, 10.8 and 33.92%. Canonical analyses of 1184 skulls from the former area and 407 from the latter indicate that mixed populations can be expected wherever close human settlement exists and wild canids remain, but that hybrids are rare in remote regions. The skulls were collected variously between 1966 and 1979; 15 equations were used to allow for differential damage to skulls. The levels of hybridization indicated by the skulls were confirmed by coat colours. The accepted colours for dingoes, (ginger, black-and-tan, and all white) were in the following percentages in inland Australia: 88.6, 3.8 and 1.9; in south-eastern Australia they were 45.9, 19.1 and 0.2%. Broken colorations, ginger with white, black or bluish patches, all black, brown or bluish, black and white, and brindle stripes, were also more numerous in the latter region (34 8%) than in the former (5.7%). Many of these variations arose in cross-breeding experiments with ginger dingoes and variously coloured domestic dogs. Historical reports recorded black dingoes but did not mention tan coloration. That may have been an oversight; if not, it may be a further indication of cross-breeding. The incidence of coat colours was not significantly different in classified dingoes, dogs and hybrids in south-eastern Australia, but ginger coats were less common in classified dogs. Those taxa and the various colorations were not more numerous near farmland than elsewhere in the forests there. A new, basic calibrating equation incorporating the length rather than the volume of auditory bulla is presented. The equation corrects also for mis-measurement of one skull variable in some of the calibrating series of dingoes. Corrigenda are presented. They do not change the general conclusions of the earlier Parts I and II of this series, but wild dingoes raised from pups in captivity did not develop foreshortened snouts as indicated earlier. The possibility remains that some may have developed wider maxillae than wild dingoes.


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