scholarly journals Improved tree height estimation of secondary forests in the Brazilian Amazon

2018 ◽  
Vol 48 (3) ◽  
pp. 179-190 ◽  
Author(s):  
Henrique Luis Godinho CASSOL ◽  
Yosio Edemir SHIMABUKURO ◽  
João Manuel de Brito CARREIRAS ◽  
Elisabete Caria MORAES
Keyword(s):  
Tree Height ◽  
Brazilian Amazon ◽  
Hyperbolic Model ◽  
Secondary Forests ◽  
Validation Data ◽  
Novel Approach ◽  
Brazilian Amazon Region ◽  
Species Groups ◽  
Ecological Species Groups ◽  
Individual Trees

ABSTRACT This paper presents a novel approach for estimating the height of individual trees in secondary forests at two study sites: Manaus (central Amazon) and Santarém (eastern Amazon) in the Brazilian Amazon region. The approach consists of adjusting tree height-diameter at breast height (H:DBH) models in each study site by ecological species groups: pioneers, early secondary, and late secondary. Overall, the DBH and corresponding height (H) of 1,178 individual trees were measured during two field campaigns: August 2014 in Manaus and September 2015 in Santarém. We tested the five most commonly used log-linear and nonlinear H:DBH models, as determined by the available literature. The hyperbolic model: H = a.DBH/(b+DBH) was found to present the best fit when evaluated using validation data. Significant differences in the fitted parameters were found between pioneer and secondary species from Manaus and Santarém by F-test, meaning that site-specific and also ecological-group H:DBH models should be used to more accurately predict H as a function of DBH. This novel approach provides specific equations to estimate height of secondary forest trees for particular sites and ecological species groups. The presented set of equations will allow better biomass and carbon stock estimates in secondary forests of the Brazilian Amazon.

scholarly journals Drivers of individual oak tree selection by acorn dispersing animals inferred from a genotyped seedling cohort

2019 ◽  
Author(s):  
Gabriel Gerzabek ◽  
Etienne K. Klein ◽  
Arndt Hampe
Keyword(s):  
Experimental Studies ◽  
Tree Height ◽  
Absolute Number ◽  
Pedunculate Oak ◽  
Plant Reproductive Success ◽  
Novel Approach ◽  
Dispersal Success ◽  
Population Structures ◽  
Oak Tree ◽  
Individual Trees

ABSTRACTSeed-dispersing animals can strongly influence plant reproductive success and resulting population structures. Few studies have disentangled different drivers of disperser foraging behavior in natural settings and their actual relevance for plant fitness. Here we adopt a novel approach to investigate the drivers of individual trees’ dispersal success in a mixed Pedunculate oak-Pyrenean oak (Quercus robur and Q. pyrenaica) forest stand. We genotyped a seedling cohort (n = 825) upon emergence and performed Bayesian parentage analyses to infer the acorn dispersal success of each oak tree in the stand. We then modeled this estimate as a function of six tree characteristics. The absolute number of animal-dispersed seedlings was exclusively predicted by crop size and the proportion of dispersed seedlings by the number of fruiting oaks in the neighborhood. Neither the oak species nor tree height, acorn size or shape played any role. Our findings contrast with results from experimental studies and suggest that effective acorn dispersers, despite being scatter-hoarders, behaved much like avian dispersers of fleshy-fruited species when selecting trees to forage on. Their behavior should favor the dominance of large, prolific trees for the dynamics and genetic composition of naturally regenerating oak stands.

scholarly journals Surgical Site Infection Following Caesarean Section by Acinetobacter Species: A Report from a Hyperendemic Setting in the Brazilian Amazon Region

2021 ◽  
Vol 9 (4) ◽  
pp. 743
Author(s):  
Blenda Gonçalves Cabral ◽  
Danielle Murici Brasiliense ◽  
Ismari Perini Furlaneto ◽  
Yan Corrêa Rodrigues ◽  
Karla Valéria Batista Lima
Keyword(s):  
Caesarean Section ◽  
Surgical Site Infection ◽  
Carbapenem Resistance ◽  
Brazilian Amazon ◽  
Amazon Region ◽  
Site Infection ◽  
Acinetobacter Species ◽  
Brazilian Amazon Region ◽  
Acinetobacter Spp ◽  
The Impact

Surgical site infection (SSI) following caesarean section is associated with increased morbidity, mortality, and significant health care costs. This study evaluated the epidemiological, clinical, and microbiological features of Acinetobacter spp. in women with SSIs who have undergone caesarean section at a referral hospital in the Brazilian Amazon region. This study included 69 women with post-caesarean SSI by Acinetobacter spp. admitted to the hospital between January 2012 and May 2015. The 69 Acinetobacter isolates were subjected to molecular species identification, antimicrobial susceptibility testing, detection of carbapenemase-encoding genes, and genotyping. The main complications of post-caesarean SSI by Acinetobacter were inadequate and prolonged antibiotic therapy, sepsis, prolonged hospitalization, and re-suture procedures. A. baumannii, A. nosocomialis and A. colistiniresistens species were identified among the isolates. Carbapenem resistance was associated with OXA-23-producing A. baumannii isolates and IMP-1-producing A. nosocomialis isolate. Patients with multidrug-resistant A. baumannii infection showed worse clinical courses. Dissemination of persistent epidemic clones was observed, and the main clonal complexes (CC) for A. baumannii were CC231 and CC236 (Oxford scheme) and CC1 and CC15 (Pasteur scheme). This is the first report of a long-term Acinetobacter spp. outbreak in women who underwent caesarean section at a Brazilian hospital. This study demonstrates the impact of multidrug resistance on the clinical course of post-caesarean infections.

scholarly journals Adjudicating Perspectives on Forest Structure: How Do Airborne, Terrestrial, and Mobile Lidar-Derived Estimates Compare?

2021 ◽  
Vol 13 (12) ◽  
pp. 2297
Author(s):  
Jonathon J. Donager ◽  
Andrew J. Sánchez Meador ◽  
Ryan C. Blackburn
Keyword(s):  
Ponderosa Pine ◽  
Laser Scanning ◽  
Canopy Cover ◽  
Basal Area ◽  
Tree Height ◽  
Absolute Error ◽  
Forest Monitoring ◽  
Individual Tree ◽  
Structural Configurations ◽  
Individual Trees

Applications of lidar in ecosystem conservation and management continue to expand as technology has rapidly evolved. An accounting of relative accuracy and errors among lidar platforms within a range of forest types and structural configurations was needed. Within a ponderosa pine forest in northern Arizona, we compare vegetation attributes at the tree-, plot-, and stand-scales derived from three lidar platforms: fixed-wing airborne (ALS), fixed-location terrestrial (TLS), and hand-held mobile laser scanning (MLS). We present a methodology to segment individual trees from TLS and MLS datasets, incorporating eigen-value and density metrics to locate trees, then assigning point returns to trees using a graph-theory shortest-path approach. Overall, we found MLS consistently provided more accurate structural metrics at the tree- (e.g., mean absolute error for DBH in cm was 4.8, 5.0, and 9.1 for MLS, TLS and ALS, respectively) and plot-scale (e.g., R2 for field observed and lidar-derived basal area, m2 ha−1, was 0.986, 0.974, and 0.851 for MLS, TLS, and ALS, respectively) as compared to ALS and TLS. While TLS data produced estimates similar to MLS, attributes derived from TLS often underpredicted structural values due to occlusion. Additionally, ALS data provided accurate estimates of tree height for larger trees, yet consistently missed and underpredicted small trees (≤35 cm). MLS produced accurate estimates of canopy cover and landscape metrics up to 50 m from plot center. TLS tended to underpredict both canopy cover and patch metrics with constant bias due to occlusion. Taking full advantage of minimal occlusion effects, MLS data consistently provided the best individual tree and plot-based metrics, with ALS providing the best estimates for volume, biomass, and canopy cover. Overall, we found MLS data logistically simple, quickly acquirable, and accurate for small area inventories, assessments, and monitoring activities. We suggest further work exploring the active use of MLS for forest monitoring and inventory.

scholarly journals Inadequate management of natural ecosystem in the Brazilian Amazon region results in the emergence and reemergence of arboviruses

2001 ◽  
Vol 17 (suppl) ◽  
pp. S155-S164 ◽  
Author(s):  
Pedro F. C. Vasconcelos ◽  
Amélia P. A. Travassos da Rosa ◽  
Sueli G. Rodrigues ◽  
Elizabeth S. Travassos da Rosa ◽  
Nicolas Dégallier ◽  
...  
Keyword(s):  
Environmental Changes ◽  
Epidemiological Data ◽  
Brazilian Amazon ◽  
Host Population ◽  
Amazon Region ◽  
Laboratory Animals ◽  
Natural Ecosystem ◽  
Brazilian Amazon Region ◽  
Mining Dam ◽  
The Impact

A total of 187 different species of arboviruses and other viruses in vertebrates were identified at the Evandro Chagas Institute (IEC) from 1954 to 1998, among more than 10,000 arbovirus strains isolated from humans, hematophagous insects, and wild and sentinel vertebrates. Despite intensive studies in the Brazilian Amazon region, especially in Pará State, very little is known about most of these viruses, except for information on date, time, source, and method of isolation, as well as their capacity to infect laboratory animals. This paper reviews ecological and epidemiological data and analyzes the impact of vector and host population changes on various viruses as a result of profound changes in the natural environment. Deforestation, mining, dam and highway construction, human colonization, and urbanization were the main manmade environmental changes associated with the emergence and/or reemergence of relevant arboviruses, including some known pathogens for humans.

Isolation and characterization of a Pseudomonas aeruginosa from a virgin Brazilian Amazon region with potential to degrade atrazine

2014 ◽  
Vol 21 (24) ◽  
pp. 13974-13978 ◽  
Author(s):  
Ana Flavia Tonelli Fernandes ◽  
Michelle Barbosa Partata da Silva ◽  
Vinicius Vicente Martins ◽  
Carlos Eduardo Saraiva Miranda ◽  
Eliana Guedes Stehling
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Brazilian Amazon ◽  
Amazon Region ◽  
Isolation And Characterization ◽  
Brazilian Amazon Region

Beta-Globin Gene Cluster Haplotypes of Amerindian Populations from the Brazilian Amazon Region

1994 ◽  
Vol 44 (3) ◽  
pp. 142-149 ◽  
Author(s):  
João Farias Guerreiro ◽  
Mauro Silvério Figueiredo ◽  
Marco Antonio Zago
Keyword(s):  
Gene Cluster ◽  
Globin Gene ◽  
Brazilian Amazon ◽  
Amazon Region ◽  
Beta Globin ◽  
Beta Globin Gene ◽  
Globin Gene Cluster ◽  
Brazilian Amazon Region

scholarly journals Parasitoid diversity (Hymenoptera: Braconidae and Figitidae) on frugivorous larvae (Diptera: Tephritidae and Lonchaeidae) at Adolpho Ducke Forest Reserve, Central Amazon Region, Manaus, Brazil

2009 ◽  
Vol 69 (2) ◽  
pp. 363-370 ◽  
Author(s):  
SGM. Costa ◽  
RB. Querino ◽  
B. Ronchi-Teles ◽  
AMM. Penteado-Dias ◽  
RA. Zucchi
Keyword(s):  
New Records ◽  
Brazilian Amazon ◽  
Amazon Region ◽  
Parasitoid Species ◽  
Forest Reserve ◽  
Natural Reservoir ◽  
Wild Fruits ◽  
Parasitism Rates ◽  
Brazilian Amazon Region ◽  
Plastic Containers

This study aimed to identify parasitoid species of frugivorous larvae and to describe the tritrophic interactions involving wild fruits, frugivorous insects and their natural enemies at Adolpho Ducke Forest Reserve (RFAD) (Manaus, AM, Brazil). Collections were performed in four 1 km² quadrants in the corners of the RFAD. The wild fruits were collected inside the forest in access trails leading to each collection area and in trails that surrounded the quadrants, up to five metres from the trail on each side. The fruits were placed in plastic containers covered with thin fabric, with a vermiculite layer on the base to allow the emergence of flies or parasitoids. Seven Braconidae species were collected, distributed among Opiinae: Doryctobracon areolatus (Szépligeti, 1911), Utetes anastrephae (Viereck, 1913), and Opius sp., and Alysiinae: Asobara anastrephae (Muesebeck, 1958), Phaenocarpa pericarpa Wharton and Carrejo, 1999, Idiasta delicata Papp, 1969, and Asobara sp. Parasitism rates by braconids and figitids are presented. Doryctobracon areolatus was the most frequent, parasitizing the highest number of fly species, and showing the highest parasitism percentage in larvae feeding on Micropholis williamii fruits. The collected figitids belong to Aganaspis nordlanderi Wharton, 1998 and A. pelleranoi (Brethes, 1924). All 15 tritrophic associations are new records for the Brazilian Amazon region. The RFAD is an important natural reservoir of frugivorous larvae parasitoids.

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