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In the current global context of climate change and the increasing demand for sustainability, optimizing agricultural production is very important in order to meet the demands for food and to mitigate environmental impact. To achieve sustainable agricultural production, particularly in regions with tropical soil and climate conditions, is necessary to adopt conservation‐oriented techniques. This includes no‐tillage system, the use of soil‐cover crops, and the application of inoculants. The objective of this research was, at the end of the 22nd cropping season, to assess the influence of soil compaction in the production of green corn (Zea mays L.) in a long‐term field experiment. This study was conducted under different soil tillage systems in a Red‐Yellow Ultisol from the Coastal Tablelands of northeastern Brazil. Three soil tillage systems were applied: Conventional Tillage (CT), Minimum Tillage (MT), and No‐tillage (NT). These were combined with four previous crops: cowpea (Vigna unguiculata), crotalaria (Crotalaria juncacea), pigeon pea (Cajanus cajan), and millet (Pennisetum glaucum), as well as two levels of nitrogen fertilizer application: (1) 100% of the recommended N dose, and (2) 50% of the recommended N dose plus Azospirillum brasilense inoculant. The experimental design consisted of strip plots with subplots divided and randomized within each strip, with three replications. Soil compaction was assessed using parameters of soil density (SD) and soil mechanical resistance to penetration (MRP) in conjunction with moisture content (MC). The principal component analysis (PCA) highlighted that conservation‐oriented systems exhibited greater soil organic carbon (SOC) levels, leading to increased productivity of commercial green corn cobs. The synergistic effect of diversifying previous crops and adopting conservation tillage systems, especially in soils under long‐term tillage, resulted in heightened productivity of commercial green corn ears. [ABSTRACT FROM AUTHOR]

Purpose: The present study describes a new species of Eimeria found in free-living S. flaveola that inhabit the city of Eugenópolis in the state of Minas Gerais, Brazil. Methods: Fecal samples from all captured birds were filtered through double gauze, mixed with 2.5% potassium dichromate (K2Cr2O7), placed in a Petri dish and incubated at 23–28 °C until 70% of the oocysts were sporulated. Results: Eimeria flaveola n. sp. from the saffron finch, Sicalis flaveola (Aves: Passeriformes), was described in Brazil. Sporulated oocysts are subspherical; 22.67 ± 1.57 (18.47–26.48) × 21.19 ± 1.42 (16.69–24.91) µm; with a shape-index of 1.07 ± 0.05 (1.00–1.25) µm and a smooth, bilayered wall, ~ 1.09 μm. A micropyle and an oocyst residuum are absent, but one polar granule is present. Sporocysts are ovoidal, 14.24 ± 1.71 (9.02–19.33) × 9.98 ± 1.02 (6.80–12.87) μm; with a shape-index of 1.43 ± 0.16 (0.74–2.11). The Stieda body is button-shaped; sub-Stieda body and para-Stieda absent. The sporocyst residuum is formed by a compact rounded mass of granules. The sporozoite is claviform, 11.53 µm in length and 2.84 µm in width, with a refractile body and a nucleus. Conclusions: Based on its morphological and morphometric characteristics, we consider E. flaveola a newly identified species. [ABSTRACT FROM AUTHOR]

Ecotones between tropical forests and lakes compose an ecosystem interconnection with a high abundance of terrestrial invertebrates, which represent an outstanding resource for the aquatic fauna. However, there is still little quantitative information on tropical forest contribution in terms of invertebrate inputs into lacustrine systems and the factors controlling this flux.To quantify the terrestrial invertebrate contribution into tropical lakes, we selected six lakes located in the Atlantic rainforest, south‐eastern Brazil, and used pan traps placed in the lakeshore. We focused on total abundance, biomass, and richness of insect orders. To assess the influence of forest and lake morphometry on terrestrial invertebrate inputs into lakes, we measured the forest–lake distance and considered the morphometric characteristics of each lake.Distance from forest negatively affected the invertebrate biomass reaching the lakes. The dissimilarity across different ecotones also increased with distance from the forest. Perimeter‐to‐area ratio negatively affected the invertebrate abundance, suggesting that more dendritic lakes receive more invertebrates from the forest.We estimated that annually, on average 21 tons of terrestrial invertebrates fall into the studied lakes, representing a massive food resource for the aquatic ecosystem. Hence, if the distance from the forest increases due, for instance, to severe drought or deforestation, it will create an herbaceous environment unable to provide such a quantity of insects to the water ecosystems, compromising aquatic and terrestrial trophic webs dynamics. [ABSTRACT FROM AUTHOR]

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Litterfall production contributes to the flow models and carbon content essential for ecosystem dynamics. The objective of the present study was to assess litterfall production rates in the Costinha mangrove forests, São Francisco River Estuary, Sergipe state, Brazil. To this end, litterfall production in the study area was monitored in five stratified stations (A, B, C, D and E) using the same channels as dividers. Ten (10) 0.25 m² litter collectors, totaling 120 litterbags, were allocated to each forest station for monthly monitoring lasting two years. The collected material was separated into fractions: leaf, flower, fruit, branch and twig, stipule and miscellaneous, and leaves and fruits were separated by species. The average litterfall production was 13.53 ton ha-1.year-1 in the first year and 13.21 ton ha-1.year-1 in the second year, with no statistically significant differences (p>0.05) between the years during the evaluation period. Generally, litterfall production in fractions presented the following descending order: leaves > branches and twigs > stipules > fruits and propagules > miscellaneous > flowers, with the leaf fractions accounting for 71.46% of the production. The Costinha mangrove forest showed variable litterfall production rates throughout the study period, but there was an increasing trend in leaf fall in warmer seasons. [ABSTRACT FROM AUTHOR]

Ecosystem-level metabolism is a good sentinel for human and natural disturbances in freshwater systems, responding from local changes (for example, land use) to regional and global changes (for example, climate). Despite the increasing understanding of metabolic processes in tropical lakes, our knowledge on how morphometric and catchment characteristics affect metabolic responses to those changes in tropical lakes is still very scarce. We investigated how metabolic rates in the upper mixed layer of twelve Brazilian tropical lakes responded to reduced rainfall, considering their lake area and drainage area ratio and the percentage of native forest cover in their drainage area. An 80% reduction in the 2013 rainy season rainfall, compared with 2012, resulted in a reduction of approximated 1 m in the water column depth, a 1–2 m deepening of the upper mixed layer, a 50% reduction in mean light availability, and a doubling in total phosphorus concentrations. These changes were associated with 38% increases in gross primary production (GPP), stimulated by higher nutrient concentrations and reduced photoinhibition. These effects of reduced rainfall were strongest in lakes with a small volume in relation to their catchment areas. Our results show that climatic-related reductions in precipitation in this tropical region will reduce lake volumes, affect temperature, water mixing, and nutrient supply with pronounced effects on lake metabolic processes and carbon cycling in this region. [ABSTRACT FROM AUTHOR]

It is well known that both niche requirements and dispersal act together to structure communities; however, it remains unclear how the underlying mechanisms create the observed patterns in nature. In plankton communities, traits related to dispersal ability (e.g. body and propagule sizes) and niche breadth (i.e. habitat generalists and habitat specialists) have recently shown promise in this regard. Here, we hypothesized that body size (a proxy for dispersal ability) and niche breadth act together to determine limnetic plankton metacommunity structure in a tropical system of natural landlocked lakes in Brazil. Our hypotheses were partially supported for zooplankton community. Copepoda showed no relation to environmental variables, and the larger-bodied Calanoida was structured only by space. The Cladocera showed the largest spatial and environmental limitation. Rotifers showed the lowest association with space; however, its pure environmental fraction was higher than expected. The phytoplankton community was largely structured by both environment and space. The spatial limitation of this group was a clear divergence from our expectations. Lastly, we revealed that intragroup variation (when species were evaluated individually) was equal or larger than between group variation, indicating that group-specific traits may play a more important role in determining metacommunity structure. [ABSTRACT FROM AUTHOR]

With the emergence of the Democratic State and Constitutional Law, replacing the Rule of Law in its purely legislative version, innumerous transformations have taken place. One of the most obvious occurred at the court activity. Before the Judge was just the manifestation of the will of the legislature, today his work space has changed. It has gained autonomy and freedom of interpretation. However, its objective has focused in one direction: the guarantee of the fundamental rights. In this scenario, it raises its performance in environmental law. With its fundamental right to protection erected, new instruments were needed to achieve them such as the polluter pays principle, clear manifestation and intervention in the private sphere defending the collective heritage. [ABSTRACT FROM AUTHOR]

This study proposed a method for identifying areas appropriate for fish farming in ground-excavated ponds using data obtained from public institutions. The method was applied to three cities located in the central-southern region of Paraná State, Brazil. In order to select appropriate areas, a geographic information system (GIS) was created using data from a digital elevation model (DEM), as well as data on soil occupation and type. A variable reclassification model (VRM) was created, and the analytic hierarchy process (AHP) method was applied to establish weights for a multi-criteria assessment of the factors. Non-classifiable areas and areas with constraints were identified and removed from the analysis. The sites classified as highly suitable or suitable represented 33.270.79 ha (18.71% of the total area), while the restricted areas represented 54,427.91 ha (30.60% of the total area). This method may represent a useful tool for decision making in the context of regional planning and may be used in the establishment of public policy and in the allocation of resources for aquaculture development. [ABSTRACT FROM AUTHOR]

We characterized extended-spectrum β-lactamases (ESBL) enzymes among Salmonella strains isolated in Brazil from 2009 to 2014. Salmonella recovered from both clinical and nonhuman (food, poultry, and environment) sources were subjected to antimicrobial susceptibility testing. β-lactamases genes were detected by polymerase chain reaction/sequencing; plasmid profiles and transferability were assessed by S1-pulsed field gel electrophoresis (PFGE). Genetic diversity was evaluated by XbaI-PFGE. Out of 630 Salmonella strains screened, 46 displayed ESBL phenotype, distributed across 11 different serotypes. blaCTX-M-8 and blaCTX-M-2 genes were detected at frequencies of 47% and 41%, respectively. blaSHV-5 and blaSHV-2 were also detected but in lower frequencies (4%, 2%). blaTEM-1 gene was detected in 22% of the strains. Most of the ESBL genes were transferable by conjugation, and the respective blaESBL gene was detected in the recipient strain, indicating the location of ESBL determinants on transferable plasmids. XbaI-PFGE revealed genomic diversity of Salmonella Typhimurium bearing blaCTX-M-2, blaCTX-M-8, blaTEM-1, and blaSHV-2 genes. Salmonella Muenchen (harboring blaCTX-M-2) and Salmonella Corvallis ( blaCTX-M-8 and blaSHV-5) showed clonal relatedness within respective serotypes. Our findings underscore the occurrence of diverse ESBL genes in several Salmonella serotypes, reinforcing the need for continuous surveillance of resistance genes circulating in human and nonhuman sources. [ABSTRACT FROM AUTHOR]

Microsporidia are widely recognized as important human pathogens with Enterocytozoon bieneusi as the most common species infecting humans and animals, including cattle. Although Brazil has the second largest cattle herd in the world and it is the largest exporter of beef there are no data on the presence or impact of E. bieneusi on this important population. To fill this knowledge gap, fecal specimens were collected from 452 cattle from pre-weaned calves to adult cattle in the state of Rio de Janeiro. Host factors including age, gender, dairy/beef, body composition, and fecal consistency were included in the study. Using molecular methods, E. bieneusi was found in 79/452 (17.5%) fecal specimens. This represents the first report of this parasite in Brazilian cattle. A significantly higher prevalence was found in calves less than 2 months of age (27.6%) and those 3–8 months of age (28.8%) versus heifers (14.1%) and adults (1.4%) ( P < 0.05). Dairy cattle (26.2%) had a higher prevalence than beef cattle (9.7%) ( P < 0.001). No correlation was found between infection and gender, body composition, and fecal consistency. Molecular characterization of the internal transcribed spacer (ITS) revealed 12 genotypes; five previously reported in cattle (BEB4, BEB8, D, EbpA and I), and seven novel genotypes (BEB11–BEB17). A phylogenetic analysis showed that 6 genotypes (D, EbpA, BEB12, BEB13, BEB15, and BEB16) identified in 18 animals clustered within the designated zoonotic Group 1 while the other 6 genotypes (I, BEB4, BEB8, BEB11, BEB14, BEB17) identified in 61 animals clustered within Group 2. The identification of genotypes in Brazilian cattle that have previously been reported in humans highlights the potential risk of zoonotic transmission and suggests that the role of cattle in transmission of human infections requires further study. [ABSTRACT FROM AUTHOR]

Delftia acidovorans is an opportunistic agent in several types of infections, both in immunocompromised and immune-competent individuals; its resistance to aminoglycosides and polymyxin, choice drugs for empirical treatment of Gram-negative infections, is remarkable. We report the antimicrobial susceptibility and the genetic relatedness of 24 D. acidovorans strains recovered from tracheal aspirates of 21 adult inpatients hospitalized in an intensive care unit at a Brazilian hospital, from 2012 to 2013. All of the isolates were recovered as pure cultures and in counts above 1,000,000 CFU/mL. None of them were susceptible to polymyxin B, amikacin, gentamicin, or tobramycin; quinolones and trimethoprim-sulfamethoxazole presented varied activities against the isolates, while β-lactam resistance was not detected. Four clusters were verified in pulsed-field gel electrophoresis analysis, and a major pulsotype comprised 10 strains. A possible, but undetermined common source, can be responsible for this strain dissemination, underscoring the need of reinforcing the adherence to disinfection and infection control standard techniques. [ABSTRACT FROM AUTHOR]

Abstract: Feces were collected from 125 sheep between January and December 2007, on ten farms in the State of Rio de Janeiro, Brazil, and examined for the presence of Cryptosporidium. Ninety samples were collected from lambs 2 to 6 months of age, and 35 were from sheep over 12 months of age. All samples were subjected to molecular analysis by polymerase chain reaction (nested PCR) in two steps of the SSU rRNA. Two samples (1.6%) from the lambs were positive, and after sequencing were identified as Cryptosporidium ubiquitum. This species has been reported worldwide and it is considered a zoonotic pathogen since it has been found and in several animal species and humans. However, because of the low frequency of C. ubiquitum found, the risk for public health in this region may not be high. [ABSTRACT FROM AUTHOR]