Effects of landscape configuration and composition on phylogenetic diversity of trees in a highly fragmented tropical forest

© 2016 British Ecological Society. Fragmentation of tropical forests is a major driver of the global extinction crisis. A key question is understanding how fragmentation impacts phylogenetic diversity, which summarizes the total evolutionary history shared across species within a community. Conserving phylogenetic diversity decreases the potential of losing unique ecological and phenotypic traits and plays important roles in maintaining ecosystem function and stability. Our study was conducted in landscapes within the highly fragmented Brazilian Atlantic forest. We sampled living trees with d.b.h. ≥ 4.8 cm in 0.1 ha plots within 28 fragment interiors and 12 fragment edges to evaluate the impacts of landscape configuration, composition and patch size, as well as edge effects, on phylogenetic diversity indices (PD, a measure of phylogenetic richness; MPD, phylogenetic distance between individuals in a community in deep evolutionary time; and MNTD, phylogenetic distance between each individual and its nearest phylogenetic neighbour). We found that PD and MPD were correlated with species richness, while MNTD was not. Best models suggest that MPD was positively related to edge density and negatively related to the number of forest patches, but that there was no effect of landscape configuration and composition metrics on PD or MNTD, or on standardized values of phylogenetic structure (sesPD, sesMPD and sesMNTD), which control for species richness. Considering all selected models for phylogenetic diversity and structure, edge density and number of forest patches were most frequently selected. With increasing patch size, we found lower PD in interiors but no change at edges and lower sesMNTD regardless of habitat type. Additionally, PD and sesMNTD were higher in interiors than at edges. Synthesis. Changes in MPD and sesMNTD suggest that extirpation of species at edges or in highly fragmented landscapes increases the dominance of species within a subset of clades (phylogenetic clustering), likely those adapted to disturbance. Smaller patch sizes are phylogenetically diverse and overdispersed, probably due to an invasion of edge-adapted species. Conservation must enhance patch area and connectivity via forest restoration; pivotally, even small forest patches are important reservoirs of phylogenetic diversity in the highly threatened Brazilian Atlantic forest

Secondary forest fragments offer important carbon‐biodiversity co‐benefits

Tropical forests store large amounts of carbon and high biodiversity, but are being degraded at alarming rates. The emerging global Forest and Landscape Restoration (FLR) agenda seeks to limit global climate change by removing carbon dioxide from the atmosphere through the growth of trees. In doing so, it may also protect biodiversity as a free co‐benefit, which is vital given the massive shortfall in funding for biodiversity conservation. We investigated whether natural forest regeneration on abandoned pastureland offers such co‐benefits, focusing for the first time on the recovery of taxonomic, phylogenetic and functional diversity of trees, including the recovery of threatened and endemic species richness, within isolated secondary forest fragments. We focused on the globally threatened Brazilian Atlantic Forest, where commitments have been made to restore one million hectares under FLR. Three decades after land abandonment, regenerating forests had recovered ~20% (72 Mg/ha−1) of the above‐ground carbon stocks of a primary forest, with cattle pasture containing just 3% of stocks relative to primary forests. Over this period, secondary forest recovered ~76% of taxonomic, 84% of phylogenetic and 96% of functional diversity found within primary forests. In addition, secondary forests had on average recovered 65% of threatened and ~30% of endemic species richness of primary Atlantic forest. Finally, we find positive relationships between carbon stock and tree diversity recovery. Our results emphasize that secondary forest fragments offer co‐benefits under FLR and other carbon‐based payments for ecosystem service schemes (e.g. carbon enhancements under REDD +). They also indicate that even isolated patches of secondary forest could help to mitigate climate change and the biodiversity extinction crisis by recovering species of high conservation concern and improving landscape connectivity

Germinação de sementes e desenvolvimento de plântulas de moringa (Moringa oleifera Lam.) em função do peso da semente e do tipo de substrato Germination of seeds and seedling development of drumstick as a function of seed weight and substrate type

Moringa oleifera Lam. é uma espécie arbórea originária do noroeste indiano, cultivada graças ao seu valor alimentar, medicinal, industrial e no tratamento de água para o consumo humano. Os efeitos do peso de sementes e do substrato na germinação e desenvolvimento das plântulas foram determinados, sob condições de casa de vegetação (sombrite 50% com nebulização intermitente) em Fortaleza (CE), de 29/11 a 14/12/02. Os tratamentos constaram de arranjo fatorial 3x3 referente a três categorias de semente: pesadas (272,41 g/1000 sementes), médias (218,88 g/1000 sementes) e leves (177,07 g/1000 sementes); e três substratos: vermiculita; Plantmax® e uma mistura à base de solo esterilizado (S), húmus de minhoca (H) e pó de coco lavado (PC), na proporção de 2:1:1, dispostos em delineamento inteiramente casualizado com quatro repetições (24 sementes/repetição). Efetuou-se a semeadura das três classes de pesos de sementes em bandejas de isopor de 72 células contendo os substratos, avaliando-se a percentagem, velocidade e tempo médio de germinação, altura da plântula, massa seca da parte aérea e massa seca total. As sementes pesadas e médias apresentaram maior percentagem e velocidade de germinação do que as leves; as sementes pesadas proporcionaram plântulas mais vigorosas; no substrato Plantmax® e na mistura (S+H+PC) a percentagem e a velocidade de germinação foi superior à vermiculita; e as plântulas desenvolveram-se melhor no substrato Plantmax®.<br>To compensate the shortage of information on the influence of seed weight and substrate over the germination and seedling development of Moringa oleifera an experiment was conducted under greenhouse conditions (50% of natural light with intermittent nebulization) in Fortaleza, Ceará State, Brazil. The treatments consisted of a 3x3 factorial arrangement [three seed weights: heavy (272.41 g/1000 seeds); medium (218.88 g/1000 seeds) and light (177.07 g/1000 seeds) and three substrates: vermiculite; Plantmax® and a v/v 2:1:1 mixture based on sterilized soil (S) plus earthworm humus (H) and washed powdered coconut peels (PCP), respectively] disposed on an entirely randomized design with four repetitions (24 seeds/repetition). The three seed classes were sown in isopor trays with 72 cells containing the respective substrate. The percentage, rate and average time for germination; height and dry weight of total and aerial parts of the seedling were measured. Heavy and medium seeds presented a higher percentage and rate of germination than light seeds; heavy seeds yielded more vigorous seedlings; the commercial substrate Plantmax® and the mixture (S+H+PCP) allowed a higher percentage and germination rate than vermiculite; the seedlings showed a better development on the commercial substrate Plantmax®

The ASOS Surgical Risk Calculator: development and validation of a tool for identifying African surgical patients at risk of severe postoperative complications

Background: The African Surgical Outcomes Study (ASOS) showed that surgical patients in Africa have a mortality twice the global average. Existing risk assessment tools are not valid for use in this population because the pattern of risk for poor outcomes differs from high-income countries. The objective of this study was to derive and validate a simple, preoperative risk stratification tool to identify African surgical patients at risk for in-hospital postoperative mortality and severe complications. Methods: ASOS was a 7-day prospective cohort study of adult patients undergoing surgery in Africa. The ASOS Surgical Risk Calculator was constructed with a multivariable logistic regression model for the outcome of in-hospital mortality and severe postoperative complications. The following preoperative risk factors were entered into the model; age, sex, smoking status, ASA physical status, preoperative chronic comorbid conditions, indication for surgery, urgency, severity, and type of surgery. Results: The model was derived from 8799 patients from 168 African hospitals. The composite outcome of severe postoperative complications and death occurred in 423/8799 (4.8%) patients. The ASOS Surgical Risk Calculator includes the following risk factors: age, ASA physical status, indication for surgery, urgency, severity, and type of surgery. The model showed good discrimination with an area under the receiver operating characteristic curve of 0.805 and good calibration with c-statistic corrected for optimism of 0.784. Conclusions: This simple preoperative risk calculator could be used to identify high-risk surgical patients in African hospitals and facilitate increased postoperative surveillance. © 2018 British Journal of Anaesthesia. Published by Elsevier Ltd. All rights reserved.Medical Research Council of South Africa gran

Safety of hospital discharge before return of bowel function after elective colorectal surgery

Background: Ileus is common after colorectal surgery and is associated with an increased risk of postoperative complications. Identifying features of normal bowel recovery and the appropriateness for hospital discharge is challenging. This study explored the safety of hospital discharge before the return of bowel function. Methods: A prospective, multicentre cohort study was undertaken across an international collaborative network. Adult patients undergoing elective colorectal resection between January and April 2018 were included. The main outcome of interest was readmission to hospital within 30 days of surgery. The impact of discharge timing according to the return of bowel function was explored using multivariable regression analysis. Other outcomes were postoperative complications within 30 days of surgery, measured using the Clavien\u2013Dindo classification system. Results: A total of 3288 patients were included in the analysis, of whom 301 (9\ub72 per cent) were discharged before the return of bowel function. The median duration of hospital stay for patients discharged before and after return of bowel function was 5 (i.q.r. 4\u20137) and 7 (6\u20138) days respectively (P &lt; 0\ub7001). There were no significant differences in rates of readmission between these groups (6\ub76 versus 8\ub70 per cent; P = 0\ub7499), and this remained the case after multivariable adjustment for baseline differences (odds ratio 0\ub790, 95 per cent c.i. 0\ub755 to 1\ub746; P = 0\ub7659). Rates of postoperative complications were also similar in those discharged before versus after return of bowel function (minor: 34\ub77 versus 39\ub75 per cent; major 3\ub73 versus 3\ub74 per cent; P = 0\ub7110). Conclusion: Discharge before return of bowel function after elective colorectal surgery appears to be safe in appropriately selected patients