scholarly journals Ecomorphological patterns of the fishes inhabiting the tide pools of the Amazonian Coastal Zone, Brazil

2013 ◽  
Vol 11 (4) ◽  
pp. 845-858 ◽  
Author(s):  
Bruno Eleres Soares ◽  
Tiago Octavio Begot Ruffeil ◽  
Luciano Fogaça de Assis Montag
Keyword(s):  
Water Column ◽  
Foraging Behavior ◽  
Coastal Zone ◽  
Principal Component ◽  
Mantel Test ◽  
Foraging Strategies ◽  
Eye Size ◽  
Taxonomic Distance ◽  
Principal Axes ◽  
Field Campaigns

The present study was based on the identification of the ecomorphological patterns that characterize the fish species found in tide pools in the Amazonian Coastal Zone (ACZ) in the Pará State, Brazil. Representatives of 19 species were collected during two field campaigns in 2011. The dominance, residence status, and trophic guild of each species were established, and morphometric data were obtained for up to 10 specimens of each species. A total of 23 ecomorphological attributes related to locomotion, position in the water column, and foraging behavior were calculated for the analysis of ecomorphological distance. Principal Component Analysis (PCA) was utilized for the evaluation of ecomorphological attributes that explained the variation among species. Mantel Test was used to correlate the taxonomic distance with species' morphological patterns and a partial Mantel Test to analyze the correlation among trophic guilds and ecomorphological patterns, controlling the effects of taxonomic distance among species. The analyses revealed two principal axes of the variation related to locomotion, correlated with the width of the caudal peduncle and the shape of the anal fin, as well as the influence of taxonomic distance on the ecomorphological characteristics of the different species. The dominant and resident species both presented a reduced capacity for continuous swimming. The two principal axes identified in relation to the position of the fish in the water column were correlated with the position of the eyes, the area of the pelvic fin, and body shape, with evidence of the influence of taxonomic distance on the morphology of the species. PCA grouped species with pelagic habits with benthonic ones. In the case of foraging behavior, the two principal axes formed by the analysis correlated with the size of the mouth, eye size, and the length of the digestive tract. Species of different guilds were grouped together, indicating a weak relationship between morphology and foraging behavior, and no relationship was found with taxonomic distance. The resident and dominant species in the tide pools of the ACZ present sedentary habits, with little evidence of the influence of taxonomic distance on the use of habitats or morphology, which was a poor indicator of foraging strategies, and showing that phylogenetically distant species could present similar ecomorphological patterns.

Partitioning of diving effort in foraging trips of northern gannets

2004 ◽  
Vol 82 (12) ◽  
pp. 1910-1916 ◽  
Author(s):  
Sue Lewis ◽  
Silvano Benvenuti ◽  
Francis Daunt ◽  
Sarah Wanless ◽  
Luigi Dall'Antonia ◽  
...  
Keyword(s):  
Foraging Behavior ◽  
Initial Rate ◽  
Trip Duration ◽  
Foraging Strategies ◽  
Foraging Activity ◽  
Trip Time

Many species of seabirds are known to undertake foraging trips that vary in duration, lasting from a few hours up to several days. However, the important question of how individuals allocate their time during foraging trips of different durations has received relatively little attention until recently. Using activity loggers, we examined the foraging behavior of chick-rearing northern gannets, Morus bassanus (L., 1758), during trips of different durations, and tested predictions concerning how foraging activity varies across trips. There was no evidence of a relationship between dive frequency during the first 3 h of a trip and trip duration, suggesting that the decision to continue on a longer trip was not affected by an adult's initial rate of encounter with prey. Flight constituted approximately 50% of total trip time, and the dive rate of birds per daylight hour was apparently unaffected by trip duration. Birds dived at similar rates on the outward and return sections of their foraging trips, which suggests that they may have been "topping up" on food on their return. Overall our results suggest that, unlike other pelagic seabirds, northern gannets at the Bass Rock do not adjust their individual foraging strategies among trips of different durations.

scholarly journals Space time evolution of the trophic state of a subtropical lagoon: Lagoa da Conceição, Florianópolis Island of Santa Catarina, Brazil

RBRH ◽  
2017 ◽  
Vol 22 (0) ◽  
Author(s):  
Victor Eduardo Cury Silva ◽  
Davide Franco ◽  
Alessandra Larissa Fonseca ◽  
Maria Luiza Fontes ◽  
Alejandro Rodolfo Donnangelo
Keyword(s):  
Water Column ◽  
Trophic Level ◽  
Algal Blooms ◽  
Trophic State ◽  
Coastal Lagoons ◽  
Principal Component ◽  
Quality Data ◽  
Santa Catarina ◽  
Water Quality Data ◽  
Subtropical Lagoon

ABSTRACT High levels of eutrophication in coastal lagoons due to human activity have been documented worldwide. Among the main impacts observed are anoxia, hypoxia, toxic algal blooms, fish kills, loss of biodiversity and loss of bathing. This study aimed to evaluate the evolution of the trophic state of Lagoa da Conceição, a subtropical lagoon located in an urbanized watershed on the island of Santa Catarina - Brazil. Spatio temporal patterns of stratification and eutrophication were investigated to understand the main biochemical changes over time. The water quality data were obtained from field campaigns supplemented with literature of the last 15 years. The vertical structure of the water column and the trophic state were evaluated by the stratification index and the TRIX index, respectively. Analyses of variance were performed in order to identify possible temporal variations in vertical stratification and trophic level. Eutrophication effects on biogeochemical cycles were verified through a multi-dimensional cluster analysis (MDS) and correlations between variables related to physical, chemical and biological processes were verified by principal component analysis (PCA). The results showed that the water column is homogeneous in all regions except in the central region of the lagoon, and the highest ammonia concentrations and lowest dissolved oxygen concentrations with periods of anoxia are observed in bottom waters. The study looked at the high trophic level of the lagoon and its inability to process the biogeochemical changes imposed by urban development.

scholarly journals Morphological and genetic diversity of Senecio vulgaris L. (Asteraceae) in Iran

2021 ◽  
Vol 80 (2) ◽  
Author(s):  
Mostafa Ebadi ◽  
Rosa Eftekharian
Keyword(s):  
Genetic Diversity ◽  
Principal Component ◽  
Morphological Characters ◽  
Mantel Test ◽  
Morphological Data ◽  
Principal Coordinates Analysis ◽  
Cauline Leaf ◽  
Senecio Vulgaris ◽  
Molecular Features ◽  
Principal Coordinates

Senecio vulgaris L., an annual herb belonging to the Asteraceae, is widely distributed in different regions of the world. There is no information on the intraspecific variations of the morphological and molecular features of this species. In the present investigation, we studied the morphological and genetic diversity of 81 accessions of S. vulgaris collected from 10 geographical populations. Eleven inter simple sequence repeat (ISSR) primers were used for the examination of genetic variations among the populations. Analysis of molecular variance (AMOVA) and GST analyses revealed significant differences among the investigated populations. A significant correlation between genetic distance and geographical distance was revealed by the Mantel test. However, reticulation analysis indicated the occurrence of gene flow among most of the populations studied. Principal component analysis (PCA) plot showed that the number of capitula, length of the cauline leaf and plant height were the most variable morphological characters. Principal coordinates analysis (PCoA) plot revealed two groups of populations, according to molecular and morphological data. The results suggested the existence of possible intraspecific taxonomic ranks within this species.

scholarly journals An Efficient Automatic Midsagittal Plane Extraction in Brain MRI

2018 ◽  
Vol 8 (11) ◽  
pp. 2203 ◽  
Author(s):  
Hafiz Rehman ◽  
Sungon Lee
Keyword(s):  
Brain Mri ◽  
Principal Component ◽  
Bilateral Symmetry ◽  
Magnetic Resonance Images ◽  
Superior Performance ◽  
Computationally Efficient ◽  
Midsagittal Plane ◽  
Accuracy And Precision ◽  
Principal Axes ◽  
Plane Extraction

In this paper, a fully automatic and computationally efficient midsagittal plane (MSP) extraction technique in brain magnetic resonance images (MRIs) has been proposed. Automatic detection of MSP in neuroimages can significantly aid in registration of medical images, asymmetric analysis, and alignment or tilt correction (recenter and reorientation) in brain MRIs. The parameters of MSP are estimated in two steps. In the first step, symmetric features and principal component analysis (PCA)-based technique is used to vertically align the bilateral symmetric axis of the brain. In the second step, PCA is used to achieve a set of parallel lines (principal axes) from the selected two-dimensional (2-D) elliptical slices of brain MRIs, followed by a plane fitting using orthogonal regression. The developed algorithm has been tested on 157 real T1-weighted brain MRI datasets including 14 cases from the patients with brain tumors. The presented algorithm is compared with a state-of-the-art approach based on bilateral symmetry maximization. Experimental results revealed that the proposed algorithm is fast (<1.04 s per MRI volume) and exhibits superior performance in terms of accuracy and precision (a mean z-distance of 0.336 voxels and a mean angle difference of 0.06).

Characterization of the photoautotrophic algal and bacterial communities in a large, shallow, subtropical lake using HPLC-PDA based pigment analysis

1998 ◽  
Vol 55 (1) ◽  
pp. 206-219 ◽  
Author(s):  
Alan D Steinman ◽  
Karl E Havens ◽  
J William Louda ◽  
Nancy M Winfree ◽  
Earl W Baker
Keyword(s):  
Water Column ◽  
Chlorophyll A ◽  
High Performance ◽  
Principal Component ◽  
Open Water ◽  
High Performance Liquid Chromatographic ◽  
Lake Okeechobee ◽  
Pheophytin A ◽  
Pigment Analysis ◽  
Liquid Chromatographic

Pigment abundances of the oxygenic and anoxygenic photoautotrophic communities from sediments and the water column in Lake Okeechobee, Florida, were estimated using reverse-phase high-performance liquid chromatographic (RP-HPLC) and photodiode array (PDA) UV/VIS (350-800 nm) spectrophotometric analyses. Thirty lipophilic pigments were identified and measured in the samples, with the most abundant overall (sediment and open-water samples combined) being chlorophyll a (38.1%), fucoxanthin (12.6%), pheophytin a (7.6%), zeaxanthin (6.6%), and pyropheophytin a (3.6%). Relative abundance of chlorophyll a was greater in the water column than in the sediments (58.3 versus 24.3% of all pigments) whereas pheophytin a comprised 9.1% of the total pigments in the sediments but only 3.7% of the total pigments in the water column. Principal component analysis (PCA) separated the sediment samples from those collected in the water column; this discrimination appears to be a function of pigment integrity in that sediment assemblages had much greater relative abundances of degraded pigments. Different regions of the lake were weakly separated by PCA based on pigments. The relatively weak degree of separation may reflect the overwhelming abundance of chlorophyll a at all sites. Overall, the pigment assemblage in Lake Okeechobee suggests cyanobacteria-diatom dominance. Out of 65 sampling events, pigments from anoxygenic photoautotrophs (e.g., bacteriochlorophylls) were detected 17 times but accounted for >20% of total chlorophyll only five times. Bacteriochlorophylls were observed only in the sediments and were most abundant during June and September, when winds were calm and temperatures warm, and at relatively shallow sites.

scholarly journals Molecular techniques in the assessment of genetic relationships between populations of Consolida (Ranunculaceae)

Caryologia ◽  
2021 ◽  
Vol 74 (2) ◽  
pp. 149-161
Author(s):  
Jing Ma ◽  
Wenyan Fan ◽  
Shujun Jiang ◽  
Xiling Yang ◽  
Wenshuai Li ◽  
...  
Keyword(s):  
Genetic Diversity ◽  
Genetic Relationships ◽  
Random Amplified Polymorphic Dna ◽  
Principal Component ◽  
Morphological Characters ◽  
Mantel Test ◽  
Molecular Techniques ◽  
Group Method ◽  
Plant Resources ◽  
High Genetic Diversity

Genetic diversity studies are essential to understand the conservation and management of plant resources in any environment. The genus Consolida (DC.) Gray (Ranuculaceae) belongs to tribe Delphinieae. It comprises approximately 52 species, including the members of the genus Aconitella Spach. No detailed Random Amplified Polymorphic DNA (RAPD) studies were conducted to study Consolida genetic diversity. Therefore, we collected and analyzed 19 species from 12 provinces of regions. Overall, one hundred and twenty-seven plant specimens were collected. We showed significant differences in quantitative morphological characters in plant species. Unweighted pair group method with arithmetic mean and principal component analysis (PCA) divided Consolida species into two groups. All primers produced polymorphic amplicons though the extent of polymorphism varied with each primer. The primer OPA-06 was found to be most powerful and efficient as it generated a total of 24 bands of which 24 were polymorphic. The Mantel test showed correlation (r = 0.34, p=0.0002) between genetic and geographical distances. We reported high genetic diversity, which clearly shows the Consolida species can adapt to changing environments since high genetic diversity is linked to species adaptability. Present results highlighted the utility of RAPD markers and morphometry methods to investigate genetic diversity in Consolida species. Our aims were 1) to assess genetic diversity among Consolida species 2) is there a correlation between species genetic and geographical distance? 3) Genetic structure of populations and taxa.

scholarly journals Genetic variability in morpho-agronomic traits of various accessions of Vigna subterranea (L.) Verdc.

2020 ◽  
Vol 116 (1) ◽  
pp. 69
Author(s):  
Maruf Olaide YEKEEN ◽  
Hafsoh Olajumoke SHAIB-RAHIM ◽  
Joy OLABODE
Keyword(s):  
Agronomic Traits ◽  
Crop Improvement ◽  
Morphological Characteristics ◽  
Principal Component ◽  
Qualitative Evaluation ◽  
Breeding Strategy ◽  
Vigna Subterranea ◽  
Agronomic Characteristics ◽  
Principal Axes ◽  
Number Of Leaves

<p><em>Vigna subterranea </em>is an indigenous African legume widely cultivated across the continent. It is a highly diverse crop exhibiting diversity in morpho-agronomic characteristics. This genetic diversity is also crucial for crop improvement as it determines which breeding strategy/ methodology to utilize in its improvement. The study evaluated the diversity in morpho-agronomic characteristics of different accessions of Bambara groundnut. ‘TVSu596’ exhibited the highest germination percentage (100 %) and shortest days to 50 % flowering (40 days) while ‘TVSu11’ had the highest number of leaves (146). Qualitative evaluation revealed the diversity existing in their morphological characteristics. Elemental analysis showed the accessions are rich in mineral elements and exhibit diversity. Principal component analysis revealed 83.37 % of total variations in morphological and yield traits by the first three principal axes. Traits such as number of leaves, petiole length, and days to 50 % flowering furnish most of the variations. Cluster analysis revealed the accessions clustered into 4 groups. These accessions are therefore recommended for utilization in development of improved cultivars or early-maturing varieties<em>.</em></p><p><em><br /></em></p>

scholarly journals Análisis del estado trófico y microfitoplancton de la zona costera de la provincia del Guayas, Ecuador

2017 ◽  
Vol 46 (2) ◽  
Author(s):  
Mónica Prado-España ◽  
Luis Troccoli-Ghinaglia ◽  
Jacqueline Cajas-Flores
Keyword(s):  
Community Structure ◽  
Dissolved Oxygen ◽  
Coastal Zone ◽  
Trophic Status ◽  
Skeletonema Costatum ◽  
Principal Component ◽  
Nutrient Concentrations ◽  
Scaling Analysis ◽  
Nutrient Loads ◽  
Trophic Index

Most fishing and aquaculture activity in Ecuador is concentrated in the Gulf of Guayaquil. However, the nutrient loads from anthropic activities could affect the water quality and the diversity of fishery resources. Surface water samples were collected to determine the temperature, salinity, dissolved oxygen, nutrients, and the community structure of microphytoplankton to determine the trophic status of the coastal zone and the inner estuary. In addition, the relation between the hydrographic variables was established through principal component analysis (PCA), and redundancy analysis (RDA) was used to analyze the effect of the environmental variables on the microphytoplankton communities. Differences in community structure were determined using multidimensional scaling analysis of similarities (MDS-Anosim), and the trophic status was established through the Karydis index. Significant differences were detected between the coastal zone and the inner estuary. Overall, the inner estuary showed a higher trophic level, with higher temperature and nutrient concentrations, and lower values for the salinity, transparency, and dissolved oxygen. Seventeen species of microphytoplankton were identified, of which 78% were diatoms, 18% dinoflagellates, 2% cyanophytes, and 2% silicoflagellates. Significant differences were detected in equitability and diversity, with fewer records in the estuarine area. The RDA showed a positive correlation (0.54; p <0.05) between Paralia sulcata, Thalassionema nitzschioides, Thalassionema frauenfeldii and nutrients and a negative correlation with salinity. In the inner estuary, Nitzschia longissima, Chaetoceros decipiens, and Skeletonema costatum were positively correlated (0.64; p <0.05) with temperature and negatively correlated with phosphate and nitrate. Differences in the community structure existed between zones, with S. costatum, T. frauenfeldii, and T. nitzschioides dominating the inner estuary and N. longissima, Guinardia striata, and Leptocylindrus danicus dominating in the coastal zone. The study area was determined to be mesotrophic. However, in the inner estuary, the values of the trophic index were higher because this area probably receives more directly the contributions from anthropic activities. Surveys with samples less than a mile from the coast are recommended to determine the trophic status in an area closer to the coast and to develop management plans to avoid threats of eutrophication.

scholarly journals The Biology of Medicinal Resource Substitution in Salvia

2021 ◽  
Author(s):  
Ning Cui ◽  
Tiezhu Chen ◽  
Baosheng Liao ◽  
Jiang Xu ◽  
Xiwen Li
Keyword(s):  
Principal Component ◽  
Mantel Test ◽  
Species Selection ◽  
Market Demand ◽  
Growth Environment ◽  
Chloroplast Genomes ◽  
Resource Substitution ◽  
Group 3 ◽  
Alternative Species ◽  
Climatic Pattern

Abstract Background: The decrease of wild reserves and the sharp increase of market demand have led to resource substitution, but it is still not clear how to discover medicinal alternative resources. Here we reveal the biology of medicinal resource substitution in the case of Salvia.Methods: A hypothesis was put forward that phylogeny and ecology were the main factors which determined alternative species selection. Phylogenetic analysis was performed based on chloroplast genomes. Spatial climatic pattern was assessed through three mathematical models. Results: S. miltiorrhiza and alternative species were mainly located in Clade 3 in topology, and their growth environment was clustered into an independent group 3 inferred from Principal Component analysis. Correlation and Maxent major climate factor analyses showed that the ecological variations within each lineage were significantly smaller than the overall divergent between any two lineages. Mantel test reconfirmed the inalienability between phylogeny and ecology (P = 0.002). Only the species that are genetically and ecologically related to S. miltiorrhiza can form a cluster with it. Conclusion: Phylogenetic relationship and geographical climate work together to determine which species has the potential to be selected as substitutes. Other medicinal plants can learn from this biology towards developing alternative resources.

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