Diel dynamic of phytoplankton functional groups in a tropical water supply, Extremoz Lake, northeastern Brazil

AIM: This study analyzed - the diel and vertical dynamics of phytoplankton functional groups in a natural tropical lake (Extremoz Lake, northeast Brazil), to investigate and understand the driver factors of the community during a severe drought period. METHODS: Sampling of the abiotic variables and phytoplankton was performed at intervals of 6 hours over 24 hours in vertical profiles, in dry and rainy seasons (according to the historical average). The phytoplankton species were grouped according to the functional groups' approach sensu Reynolds et al. (2002). RESULTS: October/12 was considered as a dry period (18.4 mm), while March/13, due to the historical average, as a rainy season, due to the low rainfall during the study period (15.7 mm), it was called severe drought. The lake showed thermal and chemical destratification in both periods. Phytoplankton biomass was higher in the dry season and their vertical distribution was stratified in both periods. In both samplings there were less algal biomass during the night. Phytoplankton functional groups of mixed and shallow systems (S1, L0 and K) were descriptors throughout the study period with higher biomass always registered in the group S1, represented by Planktolyngbya limnetica (Cyanobacteria). CONCLUSION: The lack of seasonality observed in this study, due to prolonged drought, may have influenced the pattern of homogeneous behavior in both samplings. This pattern strongly influenced the vertical distribution of phytoplankton in the two periods, with a constancy of dominance of functional descriptors groups.

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Driving forces of the diel distribution of phytoplankton functional groups in a shallow tropical lake (Lake Monte Alegre, Southeast Brazil)

Brazilian Journal of Biology ◽

10.1590/s1519-69842009000100009 ◽

2009 ◽

Vol 69 (1) ◽

pp. 75-85 ◽

Cited By ~ 12

Author(s):

LM. Rangel ◽

LHS. Silva ◽

MS. Arcifa ◽

A. Perticarrari

Keyword(s):

Vertical Distribution ◽

Functional Groups ◽

Rainy Season ◽

Phytoplankton Biomass ◽

Driving Forces ◽

Circulation Pattern ◽

Dry Period ◽

Phytoplankton Functional Groups ◽

The Vertical Distribution ◽

Cool Dry Season

Phytoplankton vertical and diel dynamics in a small shallow lake (Lake Monte Alegre, Ribeirão Preto, state of São Paulo) were investigated in two climatological periods: July 2001 (cool-dry season) and March 2002 (warm-rainy season). Monte Alegre is a eutrophic reservoir, with a warm polymictic discontinuous circulation pattern. The lake was thermally stratified in both periods, although dissolved oxygen varied less in the cool-dry period. Phytoplankton biomass was higher in the warm-rainy season and the vertical distribution was stratified in both seasons. Flagellate groups (Lm, Y, W1 and W2) and functional groups typical of shallow eutrophic environments (J, X1 and Sn) were important throughout the study period. The lake's thermal pattern strongly influenced the vertical distribution of the phytoplankton community in both periods. Biomass, functional groups and size classes of phytoplankton also were determined by the presence of more efficient herbivores in the lake, especially during the cool-dry period when phytoplankton biomass decreased.

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Nesting Substrate Characteristics of Partamona seridoensis Pedro & Camargo (Hymenoptera: Apidae) in Areas of Dry Forest in Brazil

Sociobiology ◽

10.13102/sociobiology.v64i1.1143 ◽

2017 ◽

Vol 64 (1) ◽

pp. 26 ◽

Cited By ~ 2

Author(s):

Carlo Rivero Moura Fernandes ◽

Alerson Brito Almeida ◽

Marco Antonio Del Lama ◽

Celso F Martins

Keyword(s):

Vertical Distribution ◽

Dry Forest ◽

Northeastern Brazil ◽

Nest Entrance ◽

Parental Relationship ◽

Nesting Substrate ◽

First Time ◽

Bee Colonies ◽

The Vertical Distribution

For the first time the association between Partamona seridoensis and Constrictotermes cyphergaster is described. Partamona seridoensis occurs in xeric areas of Northeastern Brazil, and it is a termitophile species as its nests are built in active and inactive arboreal termite nests of the species C. cyphergaster. This study aimed to verify the characteristics of the nesting substrate used by P. seridoensis in two areas of dry forest (caatinga) in Cariri region, Paraíba state. It has been found that the vertical distribution of termites that contained colonies of P. seridoensis varied from 10 cm to 3.60 m, while the height of the nest entrance varied from 20 cm to 3.70 m. Commiphora leptophloeos, popularly known as imburana, was the support tree of 22 (43.1%) from 51 observed termite nests that harbored bee colonies. Most (44; 86.2%) of the host termites colonies were active. Most of the colonies showed the nest entrances not directed to the east/southeast. All colonies located were housed in large termite nests, whose volumes exceed 30 liters. In the two areas surveyed, frequently the entrances of the nests were directed to other nearby colonies, suggesting a parental relationship that should be further investigated.

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Population attributes of Littoraria angulifera (Gastropoda: Littorinidae) in mangroves in Bahia State, northeastern Brazil

Brazilian Journal of Biology ◽

10.1590/1519-6984.243114 ◽

2022 ◽

Vol 82 ◽

Author(s):

G. Boehs ◽

L. A. de Freitas

Keyword(s):

Sex Ratio ◽

Vertical Distribution ◽

Spartina Alterniflora ◽

Time Distribution ◽

Northeastern Brazil ◽

Mangrove Tree ◽

Red Mangrove ◽

Continuous Reproduction ◽

Average Size ◽

The Vertical Distribution

Abstract Littoraria angulifera (Lamarck, 1822) is an estuarine gastropod of tropical occurrence, which lives mainly on trunks of mangrove tree species. This study aimed to evaluate the population attributes of this species, such as abundance, space-time distribution, sex ratio and recruitment in mangroves in Bahia State, northeastern Brazil. The specimens were collected monthly throughout 2018, on trunks of the red mangrove Rhizophora mangle L. at two heights and on two horizontal levels. Specimens that were on the marine grass Spartina alterniflora Loisel were also collected. After counting, biometrics and sexing, the specimens were returned alive to the environment. The average size and weight of L. angulifera was higher (p<0.05) in places with taller and less sparse trees and the vertical distribution on the trunks showed a preference for strata close to the soil. Both results are related to shading and protection against desiccation. Females were more abundant than males, at an approximate sex ratio F: M of 1.4: 1. Recruits were observed throughout the period, showing continuous reproduction of the species with a recruitment peak in spring (September to November). The study revealed the importance of keep the mangroves intact to allow the maintenance of the natural stocks of the species.

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Seasonal variation of the crustacean fauna in the belowground and aboveground strata in a Halodule wrightii meadow of northeastern Brazil

Iheringia Série Zoologia ◽

10.1590/1678-4766e2017048 ◽

2017 ◽

Vol 107 (0) ◽

Author(s):

Kcrishna V. S. Barros ◽

Jesser F. Souza-Filho ◽

Ricardo J. C. Paiva ◽

Catarina L. Araújo-Silva ◽

Alexandre O. Almeida ◽

...

Keyword(s):

Spatial Distribution ◽

Seasonal Variation ◽

Vertical Distribution ◽

The Other ◽

Northeastern Brazil ◽

Halodule Wrightii ◽

The Vertical Distribution

ABSTRACT The different microhabitats provided by seagrasses and the habit of the species determinate the vertical distribution of crustaceans. This study verified the influence of the seasonality on the spatial distribution of the crustacean community associated with a Halodule wrightii meadow. From April 2006 to July 2007, we performed fifteen samplings in Goiabeiras Beach, Ceará State, each with five sectioned replicates in belowground and aboveground. Cumaceans and the amphipod Hyale media (Dana, 1853) had a higher frequency, density, and dominance than the other taxa, in both strata. The community exhibited gradual changes along the study, in both the belowground and aboveground strata, but the seagrass structure was not sufficient to explain the vertical distribution of the crustacean fauna along the time.

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Assembly history modulates vertical root distribution in a grassland experiment

10.1101/2021.08.24.457510 ◽

2021 ◽

Author(s):

Inés M. Alonso-Crespo ◽

Emanuela W.A. Weidlich ◽

Vicky M. Temperton ◽

Benjamin M. Delory

Keyword(s):

Vertical Distribution ◽

Functional Groups ◽

Plant Communities ◽

Functional Group ◽

Species Level ◽

The Other ◽

Priority Effects ◽

Rooting Depth ◽

Distribution Of Roots ◽

The Vertical Distribution

The order of arrival of plant species during assembly can affect the structure and functioning of grassland communities. These so-called priority effects have been extensively studied aboveground, but we still do not know how they affect the vertical distribution of roots in the soil and the rooting depth of plant communities. To test this hypothesis, we manipulated the order of arrival of three plant functional groups (forbs, grasses and legumes) in a rhizobox experiment. Priority effects were created by sowing one functional group 10 days before the other two. Rhizoboxes in which all functional groups were sown simultaneously were used as controls. During the experiment, the mean rooting depth of plant communities was monitored using image analysis and a new methodological approach using deep learning (RootPainter) for root segmentation. At harvest, we measured aboveground (community and species level) and belowground (community level) biomass, and assessed the vertical distribution of the root biomass in different soil layers. At the community level, all scenarios where one functional group was sown before the other two had similar shoot and root productivity. At the species level, two forbs (Achillea millefolium and Centaurea jacea) benefited from arriving early, and one legume (Trifolium pratense) had a disadvantage when it was sown after the grasses. Priority effect treatments also affected the vertical distribution of roots. When grasses were sown first, plant communities rooted more shallowly than when forbs or legumes were sown first,. In addition, roots moved down the soil profile 24% more slowly in grasses-first communities. Our results highlight that plant functional group order of arrival in grassland communities can affect the vertical distribution of roots in the soil and this may have implications for species coexistence.

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