scholarly journals SINAIS CLIMÁTICOS EM ANÉIS DE CRESCIMENTO DE Cedrela fissilis EM DIFERENTES TIPOLOGIAS DE FLORESTAS OMBRÓFILAS DO SUL DO BRASIL

FLORESTA ◽  
2013 ◽  
Vol 44 (2) ◽  
pp. 323 ◽  
Author(s):  
Fernando Andreacci ◽  
Paulo Cesar Botosso ◽  
Franklin Galvão
Keyword(s):  
Atlantic Forest ◽  
Tree Rings ◽  
Rain Forest ◽  
The Other ◽  
Growth Rings ◽  
Araucaria Forest ◽  
Different Types ◽  
Pearson Correlations ◽  
Climatic Signals ◽  
South Brazil

Os anéis de crescimento de Cedrela fissilis foram analisados em duas unidades fitogeográficas do estado do Paraná, em áreas de Florestas Ombrófilas Densa e Mista, litoral e planalto, no domínio da Floresta Atlântica, buscando encontrar sinais climáticos nas séries radiais temporais de anéis de crescimento. As áreas não apresentam estação seca bem definida, com precipitações bem distribuídas ao longo do ano. Na área do litoral, as temperaturas são altas e constantes durante todo o ano, enquanto que na área do planalto as temperaturas são mais amenas, ocorrendo considerável variação durante o ano. Nas duas áreas foram coletadas 3-4 amostras radiais dos indivíduos selecionados, sendo 15 no litoral e 21 no planalto. Os anéis de crescimento foram marcados, mensurados, submetidos ao controle de qualidade por meio do programa COFECHA® e as cronologias foram geradas utilizando o programa ARSTAN®. Sinais climáticos nas séries foram identificados utilizando-se Correlações de Pearson. As séries analisadas provenientes da área de planalto apresentaram melhores correlações com as variáveis temperatura e precipitação, sendo identificados sinais climáticos, enquanto que as séries do litoral não puderam ser datadas com total acurácia. É atribuída a hipótese da competição, principalmente por luz, para explicar a dificuldade na datação dos indivíduos do litoral.Palavras-chave: Anéis de crescimento; dendrocronologia; Floresta Atlântica. AbstractClimatic signals in growth rings of Cedrela fissilis in different types of South Brazil rainforests. Cedrela fissilis tree-rings were examined in two distinct phytogeographic units of the State of Paraná, Brazil. The analysis was carried out in areas of tropical rain forest, Atlantic Forest (cost), and Araucaria Forest (plateau) in order to seek for climatic signals in tree rings series. In the coast area, temperatures are high and constant throughout the year, while in the area of the plateau, temperatures are milder and considerable variations occur during the year. In both areas 3-4 radial samples of each selected individual were collected, 15 from the coast and 21 from the plateau. Growth rings were marked, measured, submitted to quality control using the COFECHA® software, and chronologies generated using the ARSTAN® software. Climatic signals in growth rings were identified using Pearson correlations. Tree rings series from plateau revealed better correlations with temperature and rainfall compared to the coast ones; they were accurately dated while the other from coast could not be dated with accuracy. Climatic signals were found in the well-dated chronology. The hypothesis of competition, mainly by light, is raised to explain the difficulty to establish a good chronology for coast area.Keywords: Growth rings; dendrochronology; Atlantic Forest.

scholarly journals CLIMATIC NICHE DETERMINES THE GEOGRAPHIC DISTRIBUTION OF MYRTACEAE SPECIES IN BRAZILIAN SUBTROPICAL ATLANTIC FOREST

2021 ◽  
Vol 45 ◽  
Author(s):  
Jéssica Thalheimer de Aguiar ◽  
Pedro Higuchi ◽  
Ana Carolina da Silva
Keyword(s):  
Atlantic Forest ◽  
Geographic Distribution ◽  
Rain Forest ◽  
Deciduous Forest ◽  
Statistical Tests ◽  
Environmental Niche ◽  
Climatic Niche ◽  
Araucaria Forest ◽  
Explanatory Variables ◽  
Environmental Space

ABSTRACT The understanding of factors determining species geographic distribution is a fundamental aim of ecology. We investigated the environmental niche for three Myrtaceae species in the Brazilian Subtropical Atlantic Forest (BSAF), part of a global conservation hotspot. Based on a literature review, we selected one representative Myrtaceae species in three important forest types in this region: Evergreen Rain Forest (coastal plains and associated mountains ranges); Araucaria Forest, and Seasonal Deciduous Forest (continental upland areas). Geographical coordinates of their distribution were obtained from the BIEN database. As explanatory variables, we considered altitude, climate, cloud cover, and soil classes. We summarized the environmental space occupied by each pair of species using Principal Components Analysis, determined niche overlaps, and applied statistical tests to verify niche equivalences and similarities. The selected species in Evergreen Rain Forest, Araucaria Forest, and Seasonal Deciduous Forest were Myrcia splendens (Sw.) DC., Myrcia guianensis (Aubl.) DC., and Campomanesia xanthocarpa O.Berg., respectively. C. xanthocarpa showed a more restricted geographic distribution than the two Myrcia species that occur from central America to southern Brazil. Species’ geographic distribution were fundamentally determined by temperature and rainfall regimes. Only C. xanthocarpa and M. guianensis, from uplands forest formations, showed environmental niche equivalence. In conclusion, we found that both species of Myrcia showed high climatic niche amplitudes occurring throughout the climatic gradient, while C. xanthocarpa was more subtropical, distributed mostly in the south and southeast of Brazil.

scholarly journals A new modern pollen dataset describing the Brazilian Atlantic Forest

The Holocene ◽  
2019 ◽  
Vol 29 (8) ◽  
pp. 1253-1262 ◽  
Author(s):  
Vincent Montade ◽  
Marie-Pierre Ledru ◽  
Thomas Giesecke ◽  
Suzette GA Flantua ◽  
Hermann Behling ◽  
...  
Keyword(s):  
Atlantic Forest ◽  
Rain Forest ◽  
High Elevation ◽  
Habitat Destruction ◽  
Southeastern Brazil ◽  
Atlantic Rain Forest ◽  
Pollen Record ◽  
Lowland Rain Forest ◽  
Araucaria Forest ◽  
Modern Pollen

To improve our understanding of the Atlantic Forest responses to climate changes in space and time, it is essential to explore how the Brazilian Atlantic rain forest is structured as observed in modern pollen assemblages and which climate parameters determine these patterns. In this context, we compiled 196 modern pollen samples including 125 from the Atlantic Forest biome and assigned each sample to one or more eco-physiognomies. We identified seven eco-physiognomies of which four clusters of one or two eco-physiognomies were clearly distinguished, namely (1) Araucaria forest with high elevation grassland, (2) lowland rain forest, (3) semi-deciduous with riverine forests and (4) northeastern Atlantic rain forest. Climatically distinct, these clusters reflect a general temperature increase and precipitation increase from the first to the fourth cluster. Furthermore, comparison of the modern pollen dataset with the Côlonia pollen record from southeastern Brazil revealed that vegetation attributed to Araucaria forest with high elevation grassland showed an important variability with several shifts towards the lowland rain forest. As illustrated by comparison with the long fossil pollen record of Côlonia, developing such a modern training set is crucial for the understanding of responses of Atlantic Forest to environmental changes. However, additional samples are still necessary to improve characterization of different eco-physiognomies at a local scale following a defined floristic and climatic gradient. This sampling effort is becoming increasing urgent as a result of strong biodiversity loss and habitat destruction in this region.

Tree Rings—The Archaeologist's Time-Piece

1935 ◽  
Vol 1 (2) ◽  
pp. 98-108 ◽  
Author(s):  
Emil W. Haury
Keyword(s):  
Tree Rings ◽  
The Other ◽  
Annual Growth ◽  
Significant Progress ◽  
Growth Rings ◽  
Annual Growth Rings ◽  
History Of ◽  
Southwestern Archaeology ◽  
The One

Since 1929 Southwestern archaeology has stood on a much surer footing than at any other time in the history of its development. This stabilization is due to the research of Dr. A. E. Douglass of Tucson, Arizona, whose inquiries into the reaction of trees to weather, from an astronomic standpoint, led, as a ramification, to the use of the annual growth rings in trees in dating the pre-Spanish remains of man in the Southwest. From the standpoint of the archaeologist, the most significant progress date in Dr. Douglass' study was June 22, 1929. On that day ended a long search for a particular sequence of rings needed to complete the ring record. This sequence was found in a log in the Showlow ruin, and united two chronologies then extant, the one a floating series of five hundred and eighty years, the other an historic series extending from 1929 to about 1280 A.D.

scholarly journals Checklist of climbing plants in an Araucaria forest of Rio Grande do Sul State, Brazil

2014 ◽  
Vol 14 (4) ◽  
Author(s):  
Guilherme Dubal dos Santos Seger ◽  
Sandra Maria Hartz
Keyword(s):  
Species Composition ◽  
Atlantic Forest ◽  
Rio Grande ◽  
Relative Difference ◽  
Rio Grande Do Sul ◽  
Araucaria Forest ◽  
Climbing Plants ◽  
Dispersal Syndromes ◽  
Forest Sites ◽  
South Brazil

Climbing plants are remarkable components of forests, highly contributing for the diversity and dynamics of communities. Studies focusing on climbing plants are scarce and for many vegetation types little is known about climbing species composition and their traits relevant for dispersal and establishment. The focus of this study is to provide the first floristic inventory of climbing plants in an Araucaria forest of Brazil, describing the dispersal syndromes and climbing mechanisms of species and comparing these traits and species composition patterns with other study sites in Southern Brazil. We found 104 taxa belonging to 33 families, with Asteraceae (22 spp.) and Apocynaceae (14 spp.) being the richest families. Among climbing mechanisms, stem twiner (50 spp.) is the most common, followed by tendril (20 spp.) and scrambler (12 spp.), while in relation to the dispersal syndromes, anemochoric species (65 spp.) are the most relevant followed by endozoochoric (28 spp.). Three new species registries were found for Rio Grande do Sul State expanding their occurrence range towards South Brazil. The comparison of climbers’ survey sites showed two sharp groups in relation to species composition and traits proportion, Seasonal and Araucaria/Atlantic forest sites, but with no difference of traits frequency between sites. There is a predominance of stem twiners species in all sites, but the relative difference for tendril species increases in Araucaria and Atlantic forest sites. The Asteraceae and Apocynaceae families were the most relevant, contrasting to Seasonal forests of Southeast Brazil. Interesting patterns can be achieved with a more detailed classification of climbing mechanisms and the results found in this study contributes to enhance the knowledge on climbers’ traits and diversity in South Brazil.

scholarly journals Protocol for Membracidae inventory (Hemiptera, Auchenorrhyncha, Membracoidea): what are the ideal collection methods for the Atlantic Forest?

2020 ◽  
Vol 20 (2) ◽  
Author(s):  
Valberta Alves Cabral ◽  
Antonio José Creão-Duarte ◽  
Aline Lourenço ◽  
Carolina Nunes Liberal ◽  
Alessandre Pereira-Colavite
Keyword(s):  
Atlantic Forest ◽  
Light Trap ◽  
The Other ◽  
Phytophagous Insects ◽  
Light Traps ◽  
Lower Stratum ◽  
Specific Protocol ◽  
Different Types ◽  
Collection Methods ◽  
The Ideal

Abstract: Membracidae are phytophagous insects that present different types of behavior, requiring a specific protocol for fast and efficient collection. This article evaluates the best methods for sampling these insects in Atlantic Forest areas. The protocol was applied in four areas of the Atlantic Forest in Paraíba state, Brazil, and involved a team of four people at a cost of US$180 per area. Each area contained 100 sampling units subdivided into 30 yellow sticky cards in the canopy and 30 yellow sticky cards in the lower stratum, 30 active collections and 10 light traps. In total, 2,678 specimens belonging to 91 species were sampled. The highest abundance and richness values were obtained using active collection (N = 1,517; S = 42) and cards in the canopy (N = 345; S = 53). All methods exhibited high complementarity, with more than half of the species (S = 50; 54.35%) recorded exclusively by only one of the methods applied. Similarity analysis revealed that active collection differs significantly from all other methods (R = 0.10, p = 0.0001) and that the sticky cards in the canopy differ from the collection in the lower stratum (p = 0.0001), whereas the other method pairs did not exhibit significant differences. In all areas, the active collection, the sticky cards in the canopy and the lower stratum had the best sample sufficiency, with at least 60% of the estimated values. To inventory Membracidae specimens in areas of the Atlantic Forest, a protocol that combines different collection methods is required, which in principle requires more time and expense. However, it is worth noting that it is possible to adjust this protocol according to the researcher’s need. For a faster survey that includes the largest number of species, we suggest a combination of active collection and a light trap.

scholarly journals Record of aquatic invertebrates associated with the bromeliads Aechmea ornata (Baker) and Aechmea recurvata (Klotzsch) L. B. Sm in two Atlantic Rainforest fragments of south Brazil

2021 ◽  
Vol 33 ◽  
Author(s):  
Yuri Kataoka Silva ◽  
Anderson de Souza Moser ◽  
Mônica Ceneviva-Bastos ◽  
Ana Lucia Suriani Affonso
Keyword(s):  
Atlantic Forest ◽  
Aquatic Invertebrates ◽  
Animal Species ◽  
The Other ◽  
Atlantic Rainforest ◽  
Forest Fragments ◽  
Biting Midges ◽  
Insect Order ◽  
South Brazil ◽  
Important Habitat

Abstract: Bromeliads are numerous both in diversity and abundance in the Atlantic Rainforest, one of the most threatened biomes on Earth. They are also an important habitat for several animal species that live in the water retained by its rosette structure. In this study, we aimed to characterize and compare the macroinvertebrate community of two bromeliad species from Atlantic forest fragments. One is characteristic of Dense Ombrophilous Forests, Aechmea ornata, and the other occurs in Mixed Ombrophilous Forests, Aechmea recurvata. We sampled and identified macroinvertebrates form 24 bromeliads, 12 of each species. A total of 19 taxa and 656 specimens were sampled. In both bromeliad species, Diptera was the most abundant insect order (n=417), represented mostly by mosquitoes (n=227) and non-biting midges (n=107), followed by Scirtidae marsh beetles (n=216). Aechmea ornata presented higher abundance and lower invertebrate richness compared to Aechmea recurvata. Seven taxa were exclusive of A. recurvata, eight were common to both, and four, including a sponge, occurred only in A. ornata. The most abundant invertebrate taxa were common to both bromeliads and are regarded as typical of lentic environments. On the other hand, the high number of exclusive species indicates that conservation efforts should include bromeliads from these two phytophysiognomies to secure protecting the diversity of phytotelmata communities.

scholarly journals BATCH PROCESSING OF TREE-RING SAMPLES FOR RADIOCARBON ANALYSIS

Radiocarbon ◽  
2020 ◽  
pp. 1-13
Author(s):  
Alexandra Fogtmann-Schulz ◽  
Sabrina G K Kudsk ◽  
Florian Adolphi ◽  
Christoffer Karoff ◽  
Mads F Knudsen ◽  
...  
Keyword(s):  
High Precision ◽  
Tree Rings ◽  
Precision Measurement ◽  
Radiocarbon Dating ◽  
The Other ◽  
High Precision Measurement ◽  
Machine Performance ◽  
High Throughput Method ◽  
Ca 50 ◽  
Low Activity

ABSTRACT We here present a comparison of methods for the pretreatment of a batch of tree rings for high-precision measurement of radiocarbon at the Aarhus AMS Centre (AARAMS), Aarhus University, Denmark. The aim was to develop an efficient and high-throughput method able to pretreat ca. 50 samples at a time. We tested two methods for extracting α-cellulose from wood to find the most optimal for our use. One method used acetic acid, the other used HCl acid for the delignification. The testing was conducted on background 14C samples, in order to assess the effect of the different pretreatment methods on low-activity samples. Furthermore, the extracted wood and cellulose fractions were analyzed using Fourier transform infrared (FTIR) spectroscopy, which showed a successful extraction of α-cellulose from the samples. Cellulose samples were pretreated at AARAMS, and the graphitization and radiocarbon analysis of these samples were done at both AARAMS and the radiocarbon dating laboratory at Lund University to compare the graphitization and AMS machine performance. No significant offset was found between the two sets of measurements. Based on these tests, the pretreatment of tree rings for high-precision radiocarbon analysis at AARAMS will henceforth use HCI for the delignification.

Comparative Surface Imaging Study of Multifocal Diffractive Intraocular Lenses

2021 ◽  
Author(s):  
Hyeck Soo Son ◽  
Jung Min Lee ◽  
Ramin Khoramnia ◽  
Chul Young Choi
Keyword(s):  
Imaging Study ◽  
The Other ◽  
Intraocular Lenses ◽  
Optical Surface ◽  
Diffractive Optic ◽  
Atomic Force ◽  
Acceptable Range ◽  
Different Types ◽  
Concentric Pattern

Abstract Purpose To analyse and compare the surface topography and roughness of three different types of diffractive multifocal IOLs. Methods Using scanning electron microscope (SEM, Inspect F, 5.0 KV, maximum magnification up to 20,000) and atomic force microscope (AFM, Park Systems, XE-100, non-contact, area profile comparison, 10 × 10 µm, 40 × 40 µm), the surface quality of the following diffractive IOLs was studied: the AcrySof IQ PanOptix (Alcon, USA), the AT LARA 829MP (Carl Zeiss Meditec, Germany), and Tecnis Symfony (Johnson&Johnson Vision, USA). The measurements were made over three representative areas (central non-diffractive optic, central diffractive optic, and diffractive step) of each IOL. Roughness profile in terms of mean arithmetic roughness (Ra) and root-mean-squared roughness (Rq) values were obtained and compared statistically. Results In SEM examination, all IOLs showed a smooth optical surface without any irregularities at low magnification. At higher magnification, Tecnis Symfony showed unique highly regular, concentric, and lineate structures in the diffractive optic area which could not be seen in the other studied diffractive IOLs. The differences in the measured Ra and Rq values of the Tecnis Symfony were statistically significant compared to the other models (p < 0.05). Conclusion Various different topographical traits were observed in three diffractive multifocal IOLs. The Ra values of all studied IOLs were within an acceptable range. Tecnis Symfony showed statistically significant higher surface Ra values at both central diffractive optic and diffractive step areas. Furthermore, compared to its counterparts, Tecnis Symfony demonstrated highly ordered, concentric pattern in its diffractive surfaces.

RADIATION EXPOSURE TO THE BACK WITH DIFFERENT TYPES OF APRONS

2021 ◽  
Author(s):  
Seung Wan Hong ◽  
Tae Won Kim ◽  
Jae Hun Kim
Keyword(s):  
Radiation Exposure ◽  
Effective Dose ◽  
Exposure Time ◽  
The Other ◽  
Lead Apron ◽  
Type Group ◽  
Air Kerma ◽  
Different Types ◽  
The Relationship

Abstract Physicians and nurses stand with their back towards the C-arm fluoroscope when using the computer, taking things out of closets and preparing drugs for injection or instruments for intervention. This study was conducted to investigate the relationship between the type of lead apron and radiation exposure to the backs of physicians and nurses while using C-arm fluoroscopy. We compared radiation exposure to the back in the three groups: no lead apron (group C), front coverage type (group F) and wrap-around type (group W). The other wrap-around type apron was put on the bed instead of on a patient. We ran C-arm fluoroscopy 40 times for each measurement. We collected the air kerma (AK), exposure time (ET) and effective dose (ED) of the bedside table, upper part and lower part of apron. We measured these variables 30 times for each location. In group F, ED of the upper part was the highest (p &lt; 0.001). ED of the lower part in group C and F was higher than that in group W (p = 0.012). The radiation exposure with a front coverage type apron is higher than that of the wrap-around type and even no apron at the neck or thyroid. For reducing radiation exposure to the back of physician or nurse, the wrap-around type apron is recommended. This type of apron can reduce radiation to the back when the physician turns away from the patient or C-arm fluoroscopy.

scholarly journals MITOTIC CROSSING OVER AND NONDISJUNCTION IN TRANSLOCATION HETEROZYGOTES OF ASPERGILLUS

Genetics ◽  
1976 ◽  
Vol 82 (4) ◽  
pp. 605-627
Author(s):  
Etta Käfer
Keyword(s):  
Selective Advantage ◽  
The Other ◽  
Translocation Chromosome ◽  
Crossing Over ◽  
Selective Marker ◽  
Reciprocal Translocations ◽  
Poor Growth ◽  
Different Types ◽  
Diploid Genotype ◽  
One Step

ABSTRACT To analyze mitotic recombination in translocation heterozygotes of A. nidulans two sets of well-marked diploids were constructed, homo- or heterozygous for the reciprocal translocations T1(IL;VIIR) or T2(IL;VIIIR) and heterozygous for selective markers on IL. It was found that from all translocation heterozygotes some of the expected mitotic crossover types could be selected. Such crossovers are monosomic for one translocated segment and trisomic for the other and recovery depends on the relative viabilities of these unbalanced types. The obtained segregants show characteristically reduced growth rates and conidiation dependent on sizes and types of mono- and trisomic segments, and all spontaneously produce normal diploid sectors. Such secondary diploid types either arose in one step of compensating crossing over in the other involved arm, or—more conspicuously—in two steps of nondisjunction via a trisomic intermediate.—In both of the analyzed translocations the segments translocated to IL were extremely long, while those translocated from IL were relatively short. The break in I for T1(I;VII) was located distal to the main selective marker in IL, while that of T2(I;VIII) had been mapped proximal but closely linked to it. Therefore, as expected, the selected primary crossover from the two diploids with T2(I;VIII) in coupling or in repulsion to the selective marker, showed the same chromosomal imbalance and poor growth. These could however be distinguished visually because they spontaneously produced different trisomic intermediates in the next step, in accordance with the different arrangement of the aneuploid segments. On the other hand, from diploids heterozygous for T1(I;VII) mitotic crossovers could only be selected when the selective markers were in coupling with the translocation; these crossovers were relatively well-growing and produced frequent secondary segregants of the expected trisomic, 2n+VII, type. For both translocations it was impossible to recover the reciprocal crossover types (which would be trisomic for the distal segments of I and monosomic for most of groups VII or VIII) presumably because these were too inviable to form conidia.—In addition to the selected segregants of expected types a variety of unexpected ones were isolated. The conditions of selection used favour visual detection of aneuploid types, even if these produce only a few conidial heads and are not at a selective advantage. For T2(I;VIII) these "non-selected" unbalanced segregants were mainly "reciprocal" crossovers of the same phenotype and imbalance as the selected ones. For T1(I;VII) two quite different types were obtained, both possibly originating with loss of the small VII-Itranslocation chromosome. One was isolated when the selective marker in repulsion to T1(I;VII) was used and, without being homo- or hemizygous for the selective marker, it produced stable sectors homozygous for this marker. The other was obtained from both coupling and repulsion diploids and showed a near-diploid genotype; it produced practically only haploid stable sectors of the type expected from monosomics, 2n-1 for the short translocation chromosome.

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