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As human-induced environmental changes reduce niche opportunities from global to local scales, permanent shifts in species traits alter ecosystem processes. Disentangling multiscale mechanisms driving temporal changes in coastal fish biodiversity is thus critical to conservation aims. From seasonal to multiyear periods, we investigated how local environmental variation and landscape features shape temporal beta diversity (abundance-based and trait-based dissimilarities, and their components of replacement and nestedness) per zones in bays and coastal lagoons, Southeastern Brazil. At larger temporal dimensions, unaccounted processes in individual systems influenced primarily taxonomic dissimilarity, whereas functional responses to variation in marine influence varied between types of system and zones. From 2 years to seasons, taxonomic and functional dissimilarities decreased with abundance-based species replacement, and both trait-based components, respectively. Replacement processes were primarily related to marine influence (transparency, salinity, pH, and tidal phase) at larger temporal dimensions, and habitat availability (mangroves and nearby estuaries) and complexity (forest cover and landscape urbanization) in seasons. Seasonal variations in tidal phase (lower) and pH (higher), respectively, promoted taxonomic (abundance gradients) and functional (fish trait loss) nestedness under shorter environmental gradients. Spatial and temporal balances between marine influence, habitat quality, and seascape connectivity drive temporal dissimilarities in coastal fish assemblages. [ABSTRACT FROM AUTHOR]

An especially interesting question is "How many species of bats can be found simultaneously in the same cave?" This information is surprisingly rare in the literature, mainly in the Neotropics. The aim of this study was to sample bats in Gruta do Limoeiro cave, Municipality of Castelo, State of Espírito Santo, Brazil after a 53-year interval of the first survey, by the naturalist Augusto Ruschi. Four surveys were conducted in 2005 and 2006, capturing bats with mist-nets and actively exploring the cave. We recorded eleven species of three families, Phyllostomidae, Vespertilionidae and Molossidae, making Gruta do Limoeiro cave one of the most diverse caves in the World for bats. Of the 14 species found by Ruschi, seven were still present, and four species were added. The seven species lost from Ruschi's list are mainly Emballonuridae and some Phyllostomidae, probably due to landscape changes. We recommend the long-term monitoring of the Gruta do Limoeiro cave to understand the loss in diversity, and consequently in ecosystem services. [ABSTRACT FROM AUTHOR]

This study assessed the occurrence and ecological potential risk of nine selected pharmaceuticals in water samples from the Juquehy River. The river flows continuously to Juquehy Beach, known as "the jewel of the north coast" of São Paulo, Brazil. Samples were collected during Christmas and the New Year (period of December 2023-January 2024), in addition to a previous baseline weekend, to compare the loads during "celebratory parties" versus "normal operational conditions." The findings indicated that the "mass gathering" during Christmas and New Year holidays contributed significantly to an increase of the mass load of the nine pharmaceuticals flowing along to the Juquehy River, i.e., caffeine (14.40-633.00 ng/L) > losartan ( furosemide (< LOQ to 9.16 ng/L) > diclofenac (0.61-4.55 ng/L) > carbamazepine (< LOQ to 0.73 ng/L) > orphenadrine (< LOQ to 0.11 ng/L) showed higher concentrations during the New Year holiday. Conversely, atenolol (< LOQ to 13.10 ng/L) > benzoylecgonine (0.33-7.23 ng/L) > cocaine (0.12-6.59 ng/L) showed higher concentrations during the Christmas day. The individual ecological risk assessment in the Juquehy River revealed a clear environmental concern for the aquatic ecosystem. The threat to the aquatic biota is significant, with caffeine and losartan presenting a moderate level of risk. Moreover, the mixture ecological risk assessment of nine compounds indicates acute moderate risks to algae, crustaceans, and fishes, as well as chronic low risks to fishes., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Studying selected floristic changes in dry forests is fundamental to foster conservation and sustainability strategies. Objective: to analyze the occurrence of woody species in a tropical forest with a history of use. In 2008, 40 permanent plots were installed and wood with a circumference of 1.30 m at a breast height (CAP) ≥ 6 cm were measured. In 2012, newly established individuals (those that did not meet the size requirements in 2008 but did in 2012) and mortality of the remaining individuals were analyzed by computer. Where applicable, the density, frequency, and absolute dominance, importance value, newly established individuals, mortality, and gross growth for each species, along with the Shannon index were estimated. The floristic composition and diversity remain unchanged. After four years, there were few differences between species, while in most cases the growth in the basal area was positive and sometimes the number of newly established individuals exceeded the mortality. After 24 years of logging, the analyzed forest area did not reach its initial basal area stock when compared to other areas of the Caatinga that do not have a history of disturbance. [ABSTRACT FROM AUTHOR]

For 13 months, this study monitored the sedimentary organic matter composition, benthic bacteria and macrofauna at a permanent sampling station on the inner shelf (~ 40m depth) near Ubatuba in SE Brazil. The sedimentary organic matter compounds were evaluated for total organic matter content, lipid biomarkers and phytopigments. The organic matter content varied significantly over time but no clear seasonal trend was evident. Lipid biomarker composition revealed that particulate organic matter was primarily derived from autochthonous sources, such as diatoms, other microalgae, zooplankton, sediment bacteria and benthic metazoan fauna. Phytopigment results revealed that the majority of the organic matter in the sediments was refractory as opposed to labile, suggesting that the labile portion is rapidly consumed. The benthic dynamics off the coast of Ubatuba is highly influenced by the intrusion of the South Atlantic Central Water (SACW) onto the shelf, which brings nutrients up to the euphotic zone and stimulates new phytoplanktonic production. This enhances the flux of organic matter to the bottom and increases benthic biota density, mainly bacteria. These results suggest a strong and complex benthic-pelagic coupling that is influenced by both mesoscale oceanographic events (i.e., intrusion of SACW) and local events (cold fronts) through remobilization of the sediments. [ABSTRACT FROM AUTHOR]

The article presents a study related to the analysis of daily variation of zooplankton abundance and evenness in the Rosana reservoir, Brazil, based on biotic and abiotic inferences. The procedure under study included the collection of Zooplankton sample daily at three sampling stations in a lateral arm of the Rosana Reservoir. The result revealed that the zooplankton did not present significant differences in abundance and evenness among sampling stations.

Copyright of Brazilian Journal of Oceanography is the property of Instituto Oceanografico da Universidade de Sao Paulo and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In this study, we evaluate spatial and temporal variations of the water's quality used in rice fields. Every 15 days during the different phases of cultivation of the rice—vegetative, reproductive, and maturity—samples were collected from the main irrigation channel, from the surface water in the field, and from the excess-water drainage channel. The differences in the values of 13 variables were analyzed by the analysis of variance system and by the Principal Component Analysis (PCA) technique. The results demonstrate that the values observed for the presence of total coliforms, heat-tolerant coliforms, and pH were higher in the irrigation water and that the calcium and magnesium components were greater in the drainage water. The PCA results indicate that three groups of variance exist and that these three account for 77 % of the observed variances. The first principal component, (39 % of the variances), includes the variables pH, phosphorus, potassium, carbon, and turbidity; the second (28.1 %), calcium, magnesium, and conductivity; while the third accounts for only 9.9 % of the variation and incorporates the variable biological thermotolerant coliforms. The spatial pattern resulting from the distribution of the sampling locations as regards the first two principal components indicates a difference between the irrigation and drainage waters. The variables of the first and third items (except for the turbidity in the second component) reach higher values in the irrigation water, while the variables associated with the second component have higher values in the drainage water. The information provided is important for the analysis of the influence exercised by plantation management decisions on the microbiological, physical, and chemical quality of the water. The results confirm the ability of paddy rice field to filter out some of the chemicals and coliforms from the irrigation water as it passes through the agro ecosystem. [ABSTRACT FROM AUTHOR]

Abstract: Despite landscape-level changes in fruit quantity, food resources may be constantly available to frugivorous animals if they track asynchronous fruit peaks. To investigate fruit availability patterns and their consequences on bird abundance, we tested for the occurrence of seasonal patterns in fruit production at three elevations (range 500–1000 m asl) in the Brazilian Atlantic Forest over three years and compared these patterns among the elevations and years. Fruit production occurred throughout the year and showed only slight seasonality, and only at the two higher elevation sites. Contrary to expectation, fruiting peaks were neither predictable nor complementary. A few plant species (about 5%) contributed disproportionately to the high annual variation of fruit production in plant communities. We found no relationship between fruit production and bird capture rates of both generalist and specialist fruit eating species, suggesting that birds do not track fruit resources along the gradient, at least in some parts of the Atlantic Forest, or in some years. The apparent constancy of fruit availability probably does not stimulate birds to track to other elevations. In addition, plants with high annual variation in fruit production could be influencing and biasing our assessment of this relationship. [Copyright &y& Elsevier]

The relationships between the spatial and temporal variations in the abundance of the shrimp Nematopalaemon schmitti and water temperature, salinity, and texture and organic-matter content of the sediment, were analysed in Ubatumirim, Ubatuba and Mar Virado bays on the northern coast of São Paulo, Brazil. Sampling was carried out monthly, from January 1998 through December 1999, from a shrimp boat equipped with double-rig nets, along six transects in each bay. In total, 2 116 specimens of N. schmitti were caught. Their distribution differed among bays, transects and seasons (ANOVA, p < 0.05). Highest total abundance was found in areas of high organic matter content, in substrate composed mainly of very fine sand and silt and clay, and during winter and autumn. Although multiple regression analysis showed no significant relationship (p > 0.05), observations suggest that water temperature, sediment texture, organic-matter content, and the presence of biodetritus and plant fragments, provided favourable environmental conditions for the establishment of N. schmitti in the region. [ABSTRACT FROM AUTHOR]

Copyright of Brazilian Journal of Biology is the property of Instituto Internacional de Ecologia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Brazilian Journal of Oceanography is the property of Instituto Oceanografico da Universidade de Sao Paulo and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This study investigated the structure and dynamics of phytoplankton in Bitury Reservoir (Pernambuco, Brazil), over two season periods, relating the variations of density to physicochemical characteristics (pH, water temperature, electrical conductivity, turbidity, total phosphorus and total nitrogen). Samples were taken in August and October/2008 (dry period), February and April of 2009 (rainy period) in two seasons and depths. 92 taxa were identified. Bacillariophyceae showed higher densities, while Chlorophyceae showed greater diversity. During the dry period, Melosira varians was dominant, whereas in the rainy period, Aulacoseira granulata, Geitlerinema amphibium and Cylindrospermopsis raciborskii were more abundant. The Canonical Correspondence Analysis showed high correlation between the biotic and abiotic data, in which the temperature and pH were the significant variables. Turbidity and total nitrogen are responsible for light and nutrients availability and affect the specific composition and population densities. [ABSTRACT FROM AUTHOR]

We monitored seventy-two 1 ha permanent plots spread over 64 km2 of terra firme forest at Reserva Ducke (Manaus, Amazonas, Brazil) over 2-yr intervals to assess the effects of a soil and topographic gradient on the rate of change in the aboveground tree live biomass (AGLB). AGLB increased significantly over the 2-yr intervals, exhibiting a mean rate of change of 1.65 Mg/ha/yr (bootstrapped 95% CI: 1.15, 2.79). The rate of change varied according to tree size class; understory and sub-canopy trees exhibited higher rates of change. Over the whole period, the rate of change was not related to soil or topographic features of the plots, but there was evidence that the relationships varied depending on the year of measurement. In the plots monitored between 2001 and 2003 we found a significant relationship between AGLB change and the soil textural gradient, but this relationship was not evident in plots monitored between 2002 and 2004. This suggests that both the temporal variation in the soil–biomass change relationship and the size structure of the forest need to be included in models of biomass change in Amazonia. We also noted that the rate of biomass change is sensitive to the equation used to estimate AGLB. Allometric models that incorporate wood-density data provide higher per plot AGLB estimates, but lower rates of change, suggesting that variations in floristic composition have important implications for carbon cycling in diverse tropical forests. Abstract in Portuguese is available at . [ABSTRACT FROM AUTHOR]

The influence of short-term (daily) variation in environmental conditions (rainfall, wind, tide, river flow) on debris accumulation was examined on two beaches at an estuarine outlet. Sampling occurred over 60 consecutive days along two sections (Internal Area, IA; and External Area, EA) of the Paranaguá Estuary Complex's southern outlet, in Paraná, southern Brazil. The IA is sheltered from direct wave action, whereas the EA is more exposed to wave and wind action from the open ocean. The IA accounted for 71% of the total debris, while the EA accounted for 29%. Debris abundance was highest after intermediate bouts of rainfall, although river flow only affected debris accumulation in the IA. Wind and tide influenced accumulation differently across sites. These results highlight the importance of short-term variation in the accumulation of marine debris on sandy beaches, which should be considered when designing and monitoring assessment programs and removal strategies. • Environmental conditions influence debris accumulation patterns on beaches at an estuarine outlet. • The effects of short-term variation on beach-stranded debris may be dependent on beach location. • Domestic plastic is the most common type of debris found in estuarine and oceanic beaches. • Small-scale temporal studies are important in quantifying marine debris dynamics. [ABSTRACT FROM AUTHOR]

Intertidal zone of rocky shores is influenced by a wide variety of abiotic and biotic drivers. These variables can affect the species abundance at different temporal scales. In the present study our goal was to evaluate the community changes over the years using different temporal scales (fortnightly, monthly, seasonal and annual) as a tool to understand the effects of biotic (i.e. competition or facilitation) and abiotic drivers (i.e. water temperature, air temperature, tidal regime, rainfall and water quality) in abundance pattern of dominant species (Crassostrea rhizophorae , Saccostrea cuccullata , Tetraclita stalactifera and Amphibalanus amphitrite). The samples were seasonally carried out in the mid-intertidal zone in the Boa Viagem Beach in Guanabara Bay over 7 years (2010 July - 2017 June). From June 2015 to June 2017 fortnightly samplings were made in addition to seasonal sampling. The inter-annual scale was the main scale in which the differences in the percent cover of the benthic community was noted (pseudo-F = 15.96, p = 0.0001). Hierarchical ANOVA indicated that for the dominant species only the annual scale was significant while to the cryptogenic macroalgae Ulva spp. only the seasonal scale. Among the environmental variables selected, dbRDA indicated 6 of them that were significantly relevant to percent cover variation of all species explaining 86,61% of data variation (p < 0.05). While C. rhizophorae e S. cucullata and T. stalactifera exhibited similar response to the relevant environmental variables, A. amphitrite exhibited opposite response to these variables. The species responded to abiotic drivers in different temporal scales. Water temperature was a very important variable, but its effect in the population dynamics of these long-lived species needs long time scales (60 days) to manifest responses at detectable levels as well as the biotic interactions, such as competition, and the effects of bioinvasion. The niche overlap observed among S. cucullata and C. rhizophorae with A. amphitrite was highly significantly (p < 0.001) (i.e.,negative SES). Conversely for the oyster species the observed niche overlap is greater than the niche overlap expected by chance (i.e., SES positive). Environmentally constrained null model approach showed a significant (p = 0.004) relationship only between A. amphitrite and S. cucullata (C-score obs = 1200; C-score exp = 716.6), indicating a negative association. During this long and continuous monitoring, we verified that each environmental variable affects the same species at distinct temporal scales, affecting also some biotic interactions (S. cucullata × A. amphitrite) and consequently the community structure. Image 1 • Each environmental variable affects the same species at distinct temporal scales. • Long-lived species need long time scales to manifest responses at detectable levels. • Long and continuous studies are essential to identify responses with temporal delay. • Environmental variables indirectly affect species interactions and consequently the community structure. [ABSTRACT FROM AUTHOR]

The occurrence and abundance of testate amoebae in the zooplankton of the floodplain of the Upper Parana River was studied and compared with other zooplankton groups. Results showed that testate amoebae were dominant zooplankters in littoral zones of lentic and lotic environments. Species of Arcellidae were most abundant, followed by Difflugidae and Centropyxidae. The influence of environmental heterogeneity (lakes or river, littoral or pelagic zones and abiotic variables) on testate amoebae abundance was significant. Although significant differences were observed between different months, the patterns of abundance variation did not appear to be synchronously related to hydrological cycle. The results suggest that the high abundance of testate amoebae in the planktonic environment of Upper Parana River floodplain isnot determined only by stochastic process (washing out from the bottom and from the shoreline vegetation). [ABSTRACT FROM AUTHOR]