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ContextThe ecological interplay between edge and matrix effects along forest-matrix interfaces is closed linked to landscape processes modulating biodiversity and ecosystem services provision in disturbed landscapes. Improving such knowledge is therefore essential to design more efficient land use management in multifunctional landscapes.ObjectivesEstimate the avian-mediated Ecosystem Service Provision (ESP) in contrasting types of forest-matrix interfaces in tropical landscapes, and examine how local habitat and landscape attributes can predict ESPs.MethodsWe sampled bird assemblages in forest-pasture (FP) and forest-eucalyptus plantation (FE) interfaces, and estimated their potential as pest control, seed dispersal and pollination agents across human-modified landscapes in southeastern Brazil. Using Random Forest algorithm, we also quantified the relative importance of local vs. landscape attributes in predicting ESPs.ResultsThe overall ESPs was higher in FP than FE interfaces. Habitat generalist birds were important potential seed disperser and pollinator agents at both FP and FE. At forest edges, landscape forest cover best predicted pest control services, whereas the density of rural homesteads best predicted potential seed dispersal and pollination services. Local habitat features were particularly important in predicting all ESP in pastures.ConclusionsWe highlight the importance of matrix type and matrix habitat structure in modulating avian ESPs across forest-matrix interfaces in human-altered landscapes and suggest that forest cover and rural homestead density are key elements in multifunctional landscapes that consider avian ESP in both forest and matrix habitats.

The intrinsic complexity, variety of concepts and numerous ways to quantify landscape heterogeneity (LH) may hamper a better understanding of how its components relate to ecological phenomena. Our study is the first to synthesize understanding of this concept and to provide the state of the art on the subject based on a comprehensive systematic literature review of 661 articles published between 1982 and 2019. Definitions, terminologies and measurements of LH were diverse and conflicting. Most articles (534 out of 661) did not provide any definition for LH, and we found great variation among the studies that did. According to our review, only 10 studies measured the effects of different land-cover types on biotic or abiotic processes (functional LH). The remaining 651 studies measured physical attributes of the landscape without mentioning that different land-cover types may impact biotic and abiotic processes differently (structural LH). The metrics most frequently used to represent LH were the Shannon diversity index and proportion of land-cover type. Most metrics used as proxies of LH also coincided with those used to represent non-heterogeneity metrics, such as fragmentation and connectivity. We identify knowledge gaps, indicate future perspectives and propose guidelines that should be addressed when researching LH.

Nickel (Ni)-a component of urease and hydrogenase-was the latest nutrient to be recognized as an essential element for plants. However, to date there are no records of Ni deficiency for annual species cultivated under field conditions, possibly because of the non-appearance of obvious and distinctive symptoms, i.e., a hidden (or latent) deficiency. Soybean, a crop cultivated on soils poor in extractable Ni, has a high dependence on biological nitrogen fixation (BNF), in which Ni plays a key role. Thus, we hypothesized that Ni fertilization in soybean genotypes results in a better nitrogen physiological function and in higher grain production due to the hidden deficiency of this micronutrient. To verify this hypothesis, two simultaneous experiments were carried out, under greenhouse and field conditions, with Ni supply of 0.0 or 0.5 mg of Ni kg of soil. For this, we used 15 soybean genotypes and two soybean isogenic lines (urease positive, ; urease activity-null, , formerly ). Plants were evaluated for yield, Ni and N concentration, photosynthesis, and N metabolism. Nickel fertilization resulted in greater grain yield in some genotypes, indicating the hidden deficiency of Ni in both conditions. Yield gains of up to 2.9 g per plant in greenhouse and up to 1,502 kg ha in field conditions were associated with a promoted N metabolism, namely, leaf N concentration, ammonia, ureides, urea, and urease activity, which separated the genotypes into groups of Ni responsiveness. Nickel supply also positively affected photosynthesis in the genotypes, never causing detrimental effects, except for the mutant, which due to the absence of ureolytic activity accumulated excess urea in leaves and had reduced yield. In summary, the effect of Ni on the plants was positive and the extent of this effect was controlled by genotype-environment interaction. The application of 0.5 mg kg of Ni resulted in safe levels of this element in grains for human health consumption. Including Ni applications in fertilization programs may provide significant yield benefits in soybean production on low Ni soil. This might also be the case for other annual crops, especially legumes.

Phylogeographic studies provide an important framework for investigating the mechanisms operating during the earliest stages of speciation, as reproductive barriers can be examined among divergent lineages in a geographic context. We investigated the evolution of early stages of intrinsic postmating isolation among different populations and lineages of Epidendrum denticulatum, a Neotropical orchid distributed across different biomes in South America. We estimated genetic diversity and structure for both nuclear and plastid markers, using a haplotype network, differentiation tests, Bayesian assignment analysis, and divergence time estimates of the main lineages. Reproductive barriers among divergent lineages were examined by analyzing seed viability following reciprocal crossing experiments. Strong plastid phylogeographic structure was found, indicating that E. denticulatum was restricted to multiple refuges during South American forest expansion events. In contrast, significant phylogeographic structure was not found for nuclear markers, suggesting higher gene flow by pollen than by seeds. Large asymmetries in seed set were observed among different plastid genetic groups, suggesting the presence of polymorphic genic incompatibilities associated with cytonuclear interactions. Our results confirm the importance of phylogeographic studies associated with reproductive isolation experiments and suggest an important role for outbreeding depression during the early stages of lineage diversification.

The production of animal-based foods from native breeds have a synergistic relationship with the regional culture, the local climate, and mainly the maintenance of alternative genetic resources for a system with a lower environmental impact. Thus the efficiency of conservation and production depends on assessing the variability of these local breeds. In the case of Curraleiro Pé-duro cattle, the most adapted individuals have undergone natural selection over five hundred years in the Brazilian savannas, mating with little or no human interference. The peculiarities of these biomes, where the regional flora is the food base and cattle is raised in extensive areas, likely influenced the genetic composition of the different groups that make up the first cattle breed of Brazil. To evaluate the composition, diversity, variation, differentiation, and genetic structure of the populations studied, samples of hair follicles from 474 individuals of different animal categories (calves, yearlings, heifers, cows, and bulls) from three farms, defined as subpopulations \"A\", \"B\", and \"C\", were collected. The animals were genotyped for 17 microsatellite markers using a DNA sequencer. After verification of monomorphic alleles, alleles outside the expected size range, and for the presence of stutter bands, the results were subjected to statistical analysis. The markers used were suitable for the proposed application with a mean Polymorphism Information Content (PIC) of 0.62. On average, the effective alleles were 4.25 per marker, with mean heterozygosities of 0.74 (observed and expected), which was lower in herd A (0.70) in comparison to herds B (0.77) and C (0.74). The analysis of molecular variance (AMOVA) revealed a higher rate of variation within herds (98.5%) and lower among herds (1.5%) (F ranging from 0.00723 and 0.03198; -values < 0.05). However no significant differences among herds where found with the Mantel test based on geographic distances. The formation of genetic clusters of all animals sampled with the software Structure resulted in minimum cluster values, with two main genetic groups (  = 2) observed among the evaluated animals. Therefore, based on PIC and heterozygosity values, a wide genetic diversity was observed, despite little differences in population structure (AMOVA, F , and Structure results) among sampling sites.

Aim: Phylogeographical studies in the Brazilian Atlantic Forest (BAF) have mostly included species associated with forest habitats, whereas taxa associated with grassland and sand-dune plant communities have so far been largely overlooked. This study examines the phylogeography of the orchid Epidendrum fulgens, which occurs on coastal sand dunes and granitic outcrops, in order to identify major genetic divergences or disjunctions across the range of the species and to investigate the genetic signatures of past range contractions and expansions. Location: Southern and south-eastern seashore vegetation along the BAF biome, and granitic and arenitic outcrops that occur in the subtropical grassland plant communities located south of the BAF. Methods: Nine nuclear and four plastid microsatellite loci were used to genotype 424 individuals from 16 populations across the distributional range of E. fulgens. For both sets of markers, we estimated genetic diversity and population differentiation, testing for a north-south gradient of genetic diversity. The plastid haplotype network and a Bayesian assignment analysis of nuclear markers were used to infer population structure. Past demographic changes were investigated using a coalescence approach. Results: A deep disjunction was found between northern populations within the BAF and southern populations outside the BAF that occur on granitic and arenitic outcrops. Recent demographic reductions were detected in northern populations on coastal sands. Such demographic changes were not expected for those populations, as previous studies with forest species had found evidence of population expansion in the same areas. Higher genetic diversity was found in southern populations on granite, in contrast to patterns observed in previous studies of forest species. Main conclusions: The results are consistent with the long-term persistence of E. fulgens. Bottlenecks were detected in populations from areas where population expansion events have been detected in other plant (and animal) species, suggesting that forest expansion after the Last Glacial Maximum played a role in the population fragmentation and decrease in genetic diversity in E. fulgens. A substantial genetic division in E. fulgens corresponds to the 'Portal de Torres', a region that demarcates the northern limits of subtropical grassland plant communities and the southern limits of the BAF.

The hypothesis that lung collapse is detrimental during the acute respiratory distress syndrome is still debatable. One of the difficulties is the lack of an efficient maneuver to minimize it. To test if a bedside recruitment strategy, capable of reversing hypoxemia and collapse in > 95% of lung units, is clinically applicable in early acute respiratory distress syndrome. Prospective assessment of a stepwise maximum-recruitment strategy using multislice computed tomography and continuous blood-gas hemodynamic monitoring. Twenty-six patients received sequential increments in inspiratory airway pressures, in 5 cm H(2)O steps, until the detection of Pa(O(2)) + Pa(CO(2)) >or= 400 mm Hg. Whenever this primary target was not met, despite inspiratory pressures reaching 60 cm H(2)O, the maneuver was considered incomplete. If there was hemodynamic deterioration or barotrauma, the maneuver was to be interrupted. Late assessment of recruitment efficacy was performed by computed tomography (9 patients) or by online continuous monitoring in the intensive care unit (15 patients) up to 6 h. It was possible to open the lung and to keep the lung open in the majority (24/26) of patients, at the expense of transient hemodynamic effects and hypercapnia but without major clinical consequences. No barotrauma directly associated with the maneuver was detected. There was a strong and inverse relationship between arterial oxygenation and percentage of collapsed lung mass (R = - 0.91; p < 0.0001). It is often possible to reverse hypoxemia and fully recruit the lung in early acute respiratory distress syndrome. Due to transient side effects, the required maneuver still awaits further evaluation before routine clinical application.

Recent phylogenomic analyses based on the maternally inherited plastid organelle have enlightened evolutionary relationships between the subfamilies of Orchidaceae and most of the tribes. However, uncertainty remains within several subtribes and genera for which phylogenetic relationships have not ever been tested in a phylogenomic context. To address these knowledge-gaps, we here provide the most extensively sampled analysis of the orchid family to date, based on 78 plastid coding genes representing 264 species, 117 genera, 18 tribes and 28 subtribes. Divergence times are also provided as inferred from strict and relaxed molecular clocks and birth–death tree models. Our taxon sampling includes 51 newly sequenced plastid genomes produced by a genome skimming approach. We focus our sampling efforts on previously unplaced clades within tribes Cymbidieae and Epidendreae. Our results confirmed phylogenetic relationships in Orchidaceae as recovered in previous studies, most of which were recovered with maximum support (209 of the 262 tree branches). We provide for the first time a clear phylogenetic placement for Codonorchideae within subfamily Orchidoideae, and Podochilieae and Collabieae within subfamily Epidendroideae. We also identify relationships that have been persistently problematic across multiple studies, regardless of the different details of sampling and genomic datasets used for phylogenetic reconstructions. Our study provides an expanded, robust temporal phylogenomic framework of the Orchidaceae that paves the way for biogeographical and macroevolutionary studies.

Background Because of their fragmented nature, inselberg species are interesting biological models for studying the genetic consequences of disjoint populations. Inselbergs are commonly compared with oceanic islands, as most of them display a marked ecological isolation from the surrounding area. The isolation of these rock outcrops is reflected in the high number of recorded endemic species and the strong floristic differences between individual inselbergs and adjacent habitats. We examined the genetic connectivity of orchids Epidendrum cinnabarinum and E. secundum adapted to Neotropical inselbergs of northeastern Brazil. Our goals were to identify major genetic divergences or disjunctions across the range of the species and to investigate potential demographic and evolutionary mechanisms leading to lineage divergence in Neotropical mountain ecosystems. Results Based on plastid markers, high genetic differentiation was found for E. cinnabarinum ( F ST  = 0.644) and E. secundum ( F ST  = 0.636). Haplotypes were not geographically structured in either taxon, suggesting that restricted gene flow and genetic drift may be significant factors influencing the diversification of these inselberg populations. Moreover, strong differentiation was found between populations over short spatial scales, indicating substantial periods of isolation among populations. For E. secundum , nuclear markers indicated higher gene flow by pollen than by seeds. Conclusions The comparative approach adopted in this study contributed to the elucidation of patterns in both species. Our results confirm the ancient and highly isolated nature of inselberg populations. Both species showed similar patterns of genetic diversity and structure, highlighting the importance of seed-restricted gene flow and genetic drift as drivers of plant diversification in terrestrial islands such as inselbergs.

Cattle weight development is highly correlated with some body measurements. Based on the relationship between morphometric measurements and body mass, our aim was to develop regression equations to estimate the body weight of Curraleiro Pé-Duro (CPD) cattle to be used in farms that lack access to weighting scales. Data from 1023 animals from four farms on withers height (WH), body length (BL), body score (BS), heart girth (HG), permanent teeth (PT), scrotal perimeter (SP), and live weight were used. The animals were classified into five categories depending on age and/or sex: newborns (NB), calves, weaned animals, cows, and bulls. The best models are GLM with Gamma, Gamma, inverse Gaussian, Gaussian, and Gamma distributions for NB, calves, weaned animals, cows, and bulls, respectively. Predictive modeling for bulls was the best performing overall, with a correlation of 0.97 between the estimated by the model and the obtained with a weighting scale. For NB, calves, weaned animals, and cows, the correlation (r) was 0.85, 0.90, 0.95, and 0.87, respectively. The evaluated models are adequate to be used as a technical solution to estimate weight in a cattle production system.