Caracterização fitossociológica e fitogeográfica de um trecho de floresta ciliar em Alfredo Wagner, SC, como subsídio para restauração ecológica

http://dx.doi.org/10.5902/1980509812342The understanding of floristic and structure of tree communities is essential to subside the strategies offorest restoration. In this sense, a phyto-sociological survey was conducted in a forest fragment situated along a tributary of Caeté river, in Alfredo Wagner, state of Santa Catarina, in order to: i) know the structureof trees and flora in this forest, ii) classify the species found according to ecological groups and iii) comparethe flora of the study area with other studies in Araucaria forest (FOM), Atlantic Rain Forest (FOD) andthe transition area between FOM-FOD of Santa Catarina state. In this fragment, 10 plots of 400 m2 wereallocated, where all individual trees with the circumference at breast height (CBH, measured at 1.30 mabove the ground) greater than or equal to 15.7 cm were measured, marked and identified. The species wereclassified into the following succession groups: pioneer, climax light-demanding or climax shade-tolerant.The Rectified Correspondence Analysis (DCA) was used for the floristic comparison. The structure of thetree component was described by the density, frequency, dominance and importance value (VI). The resultsshowed elevated species richness (98 species). It was found typical species of FOM, such as Araucariaangustifolia (Bert.) Kuntze, and species characteristics of FOD such as Byrsonima ligustrifolia A.Juss.,confirming the study fragment as an area of ecological tension between FOM and FOD. The species withmost elevated VI were Psychotria vellosiana Benth., Alsophila setosa Kaulf. and Guatteria australis A.St.-Hil. The species with elevated VI, for their considerable representation in the area, are important in therestoration of degraded riparian forests in the region. The species seedlings plantation should be plannedobserving the group successional of each species, planting pioneer and light-demanding climax speciesfirst (e.g. Psychotria vellosiana), followed by, after the shading of the area, shade-tolerant species (e.g.Alsophila setosa e Guatteria australis).http://dx.doi.org/10.5902/1980509812342Os conhecimentos florístico e estrutural da comunidade arbórea são fundamentais para subsidiar estratégias de restauração florestal. Neste sentido, foi realizado um levantamento fitossociológico em um fragmento florestal situado nas margens de um tributário do Rio Caeté em Alfredo Wagner, SC, objetivando: i) conhecer a estrutura e a florística da vegetação arbórea dessa floresta; ii) classificar as espécies encontradas em grupos ecológicos e iii) comparar a florística da área estudada com outros estudos realizados em Floresta Ombrófila Mista (FOM), Floresta Ombrófila Densa (FOD) e área de transição entre FOM-FOD de Santa Catarina. Nesse fragmento foram alocadas 10 parcelas de 400 m2 onde todos os indivíduos arbóreos que apresentaram Circunferência a Altura do Peito (CAP, medido a 1,30 m do solo) igual ou superior a 15,7 cm foram medidos, marcados e identificados. As espécies foram classificadas nos grupos sucessionais: pioneira, clímax exigente de luz ou clímax tolerante à sombra. Para a comparação florística com outros remanescentes, foi utilizada a Análise de Correspondência Retificada (DCA). A estrutura do componente arbóreo foi descrita pela densidade, frequência, dominância e Valor de Importância (VI). Os resultados demonstram elevada riqueza florística (98 espécies). Foi possível constatar espécies típicas de FOM, como Araucaria angustifolia (Bert.) Kuntze, e espécies características de FOD, como Byrsonima ligustrifolia A.Juss., confirmando a característica do fragmento estudado de pertencer a uma área de tensão ecológica, padrão confirmado na comparação da similaridade florística. As espécies com maior VI foram Psychotria vellosiana Benth., Alsophila setosa Kaulf. e Guatteria australis A.St.-Hil. Estas e outras espécies de alto VI, por suas consideráveis representatividades na área, são importantes na restauração de florestas ciliares degradadas na região. Os plantios deverão ser planejados obedecendo-se ao grupo sucessional das espécies, plantando-se as espécies pioneiras e clímax exigentes de luz em um primeiro momento (e.g. Psychotria vellosiana), seguidas, quando houver o sombreamento da área, das espécies clímax tolerantes à sombra (e.g. Alsophila setosa e Guatteria australis)

PHYTOSOCIOLOGICAL AND PHYTOGEOGRAPHIC CHARACTERIZATION OF A RIPARIAN FOREST SECTOR IN ALFREDO WAGNER, SANTA CATARINA STATE, AS SUBSIDY FOR ECOLOGICAL RESTORATION

Os conhecimentos flor\uedstico e estrutural da comunidade arb\uf3rea s\ue3o fundamentais para subsidiar estrat\ue9gias de restaura\ue7\ue3o florestal. Neste sentido, foi realizado um levantamento fitossociol\uf3gico em um fragmento florestal situado nas margens de um tribut\ue1rio do Rio Caet\ue9 em Alfredo Wagner, SC, objetivando: i) conhecer a estrutura e a flor\uedstica da vegeta\ue7\ue3o arb\uf3rea dessa floresta; ii) classificar as esp\ue9cies encontradas em grupos ecol\uf3gicos e iii) comparar a flor\uedstica da \ue1rea estudada com outros estudos realizados em Floresta Ombr\uf3fila Mista (FOM), Floresta Ombr\uf3fila Densa (FOD) e \ue1rea de transi\ue7\ue3o entre FOM-FOD de Santa Catarina. Nesse fragmento foram alocadas 10 parcelas de 400 m2 onde todos os indiv\uedduos arb\uf3reos que apresentaram Circunfer\ueancia a Altura do Peito (CAP, medido a 1,30 m do solo) igual ou superior a 15,7 cm foram medidos, marcados e identificados. As esp\ue9cies foram classificadas nos grupos sucessionais: pioneira, cl\uedmax exigente de luz ou cl\uedmax tolerante \ue0 sombra. Para a compara\ue7\ue3o flor\uedstica com outros remanescentes, foi utilizada a An\ue1lise de Correspond\ueancia Retificada (DCA). A estrutura do componente arb\uf3reo foi descrita pela densidade, frequ\ueancia, domin\ue2ncia e Valor de Import\ue2ncia (VI). Os resultados demonstram elevada riqueza flor\uedstica (98 esp\ue9cies). Foi poss\uedvel constatar esp\ue9cies t\uedpicas de FOM, como Araucaria angustifolia (Bert.) Kuntze, e esp\ue9cies caracter\uedsticas de FOD, como Byrsonima ligustrifolia A.Juss., confirmando a caracter\uedstica do fragmento estudado de pertencer a uma \ue1rea de tens\ue3o ecol\uf3gica, padr\ue3o confirmado na compara\ue7\ue3o da similaridade flor\uedstica. As esp\ue9cies com maior VI foram Psychotria vellosiana Benth., Alsophila setosa Kaulf. e Guatteria australis A.St.-Hil. Estas e outras esp\ue9cies de alto VI, por suas consider\ue1veis representatividades na \ue1rea, s\ue3o importantes na restaura\ue7\ue3o de florestas ciliares degradadas na regi\ue3o. Os plantios dever\ue3o ser planejados obedecendo-se ao grupo sucessional das esp\ue9cies, plantando-se as esp\ue9cies pioneiras e cl\uedmax exigentes de luz em um primeiro momento (e.g. Psychotria vellosiana), seguidas, quando houver o sombreamento da \ue1rea, das esp\ue9cies cl\uedmax tolerantes \ue0 sombra (e.g. Alsophila setosa e Guatteria australis).The understanding of floristic and structure of tree communities is essential to subside the strategies of forest restoration. In this sense, a phyto-sociological survey was conducted in a forest fragment situated along a tributary of Caet\ue9 river, in Alfredo Wagner, state of Santa Catarina, in order to: i) know the structure of trees and flora in this forest, ii) classify the species found according to ecological groups and iii) compare the flora of the study area with other studies in Araucaria forest (FOM), Atlantic Rain Forest (FOD) and the transition area between FOM-FOD of Santa Catarina state. In this fragment, 10 plots of 400 m2 were allocated, where all individual trees with the circumference at breast height (CBH, measured at 1.30 m above the ground) greater than or equal to 15.7 cm were measured, marked and identified. The species were classified into the following succession groups: pioneer, climax light-demanding or climax shade-tolerant. The Rectified Correspondence Analysis (DCA) was used for the floristic comparison. The structure of the tree component was described by the density, frequency, dominance and importance value (VI). The results showed elevated species richness (98 species). It was found typical species of FOM, such as Araucaria angustifolia (Bert.) Kuntze, and species characteristics of FOD such as Byrsonima ligustrifolia A.Juss., confirming the study fragment as an area of ecological tension between FOM and FOD. The species with most elevated VI were Psychotria vellosiana Benth., Alsophila setosa Kaulf. and Guatteria australis A.St.- Hil. The species with elevated VI, for their considerable representation in the area, are important in the restoration of degraded riparian forests in the region. The species seedlings plantation should be planned observing the group successional of each species, planting pioneer and light-demanding climax species first (e.g. Psychotria vellosiana), followed by, after the shading of the area, shade-tolerant species (e.g. Alsophila setosa e Guatteria australis)

Partição espacial de espécies arbóreas em função da drenagem do solo em um fragmento de Floresta com Araucária no sul do Brasil

http://dx.doi.org/10.5902/1980509814580The relationship vegetation-soil can contribute to understand the forest structure, supporting biodiversity conservation. Thus, the aim of the present study was to verify the existence of spatial partition of the tree species community in an Araucaria forest fragment in function of soil drainage. For this sake, an environmental characterization (soil drainage, physical and chemical soil properties, topography, compression of soil, depth of soil and canopy cover) was realized in 25 plots of 20 x 20m, where tree individuals, with circumference at breast height ≥15.7 cm were previously counted, measured and identified. The data were analysed by Mann-Withney test, non-parametric multivariate ANOVA (NPMANOVA), multivariate analysis (NMDS) and indicator species analysis. In this small spatial scale there were two drainage classes, corresponding to well and moderately-drained soils, with environmental differences that determined the richness, the spatial partition of the tree community and the occurrence of indicator species. Thus, we conclude that in the study forest fragment soil drainage spatial variations were determinant in the floristic-structural heterogeneity observed in tree community. http://dx.doi.org/10.5902/1980509814580O estudo das relações entre a vegetação e os solos pode auxiliar na compreensão da estrutura de uma comunidade florestal, dando suporte à conservação da biodiversidade. Assim, o presente estudo teve como objetivo avaliar a existência da partição espacial da comunidade de espécies arbóreas em um fragmento de Floresta com Araucária, em função da drenagem do solo. Para este propósito, foi realizada a caracterização ambiental (drenagem do solo, propriedades físicas e químicas do solo, topografia, compactação dos solos, profundidade dos solos e cobertura do dossel) em 25 parcelas de 20x20 m, onde indivíduos de espécies arbóreas, com circunferência a altura do peito (CAP) maior ou igual a 15,7 cm, foram previamente contados, medidos e identificados. Os dados foram analisados por meio do teste de Mann-Withney, análise de variância multivariada não paramétrica (NPMANOVA), análise multivariada (NMDS) e análise de espécies indicadoras. Os locais foram classificados como bem e moderadamente drenados, com diferenças ambientais que determinaram a riqueza, a partição espacial da comunidade e a ocorrência de espécies indicadoras na pequena escala espacial considerada. Desta forma, conclui-se que, no fragmento florestal estudado, as variações espaciais na drenagem do solo foram determinantes na heterogeneidade da composição florística-estrutural observada

TREE SPECIES COMMUNITY SPATIAL PARTITION IN FUNCTION OF SOIL DRAINAGE IN AN ARAUCARIA FOREST FRAGMENT IN SOUTHERN BRAZIL

O estudo das rela\ue7\uf5es entre a vegeta\ue7\ue3o e os solos pode auxiliar na compreens\ue3o da estrutura de uma comunidade florestal, dando suporte \ue0 conserva\ue7\ue3o da biodiversidade. Assim, o presente estudo teve como objetivo avaliar a exist\ueancia da parti\ue7\ue3o espacial da comunidade de esp\ue9cies arb\uf3reas em um fragmento de Floresta com Arauc\ue1ria, em fun\ue7\ue3o da drenagem do solo. Para este prop\uf3sito, foi realizada a caracteriza\ue7\ue3o ambiental (drenagem do solo, propriedades f\uedsicas e qu\uedmicas do solo, topografia, compacta\ue7\ue3o dos solos, profundidade dos solos e cobertura do dossel) em 25 parcelas de 20x20 m, onde indiv\uedduos de esp\ue9cies arb\uf3reas, com circunfer\ueancia a altura do peito (CAP) maior ou igual a 15,7 cm, foram previamente contados, medidos e identificados. Os dados foram analisados por meio do teste de Mann-Withney, an\ue1lise de vari\ue2ncia multivariada n\ue3o param\ue9trica (NPMANOVA), an\ue1lise multivariada (NMDS) e an\ue1lise de esp\ue9cies indicadoras. Os locais foram classificados como bem e moderadamente drenados, com diferen\ue7as ambientais que determinaram a riqueza, a parti\ue7\ue3o espacial da comunidade e a ocorr\ueancia de esp\ue9cies indicadoras na pequena escala espacial considerada. Desta forma, conclui-se que, no fragmento florestal estudado, as varia\ue7\uf5es espaciais na drenagem do solo foram determinantes na heterogeneidade da composi\ue7\ue3o flor\uedsticaestrutural observada.The relationship vegetation-soil can contribute to understand the forest structure, supporting biodiversity conservation. Thus, the aim of the present study was to verify the existence of spatial partition of the tree species community in an Araucaria forest fragment in function of soil drainage. For this sake, an environmental characterization (soil drainage, physical and chemical soil properties, topography, compression with circumference at breast height 6515.7 cm were previously counted, measured and identified. The data were analysed by Mann-Withney test, non-parametric multivariate ANOVA (NPMANOVA), multivariate analysis (NMDS) and indicator species analysis. In this small spatial scale there were two drainage classes, corresponding to well and moderately-drained soils, with environmental differences that determined the richness, the spatial partition of the tree community and the occurrence of indicator species. Thus, we conclude that in the study forest fragment soil drainage spatial variations were determinant in the floristicstructural heterogeneity observed in tree community

PHYTOSOCIOLOGICAL AND PHYTOGEOGRAPHIC CHARACTERIZATION OF A RIPARIAN FOREST SECTOR IN ALFREDO WAGNER, SANTA CATARINA STATE, AS SUBSIDY FOR ECOLOGICAL RESTORATION

Os conhecimentos florístico e estrutural da comunidade arbórea são fundamentais para subsidiar estratégias de restauração florestal. Neste sentido, foi realizado um levantamento fitossociológico em um fragmento florestal situado nas margens de um tributário do Rio Caeté em Alfredo Wagner, SC, objetivando: i) conhecer a estrutura e a florística da vegetação arbórea dessa floresta; ii) classificar as espécies encontradas em grupos ecológicos e iii) comparar a florística da área estudada com outros estudos realizados em Floresta Ombrófila Mista (FOM), Floresta Ombrófila Densa (FOD) e área de transição entre FOM-FOD de Santa Catarina. Nesse fragmento foram alocadas 10 parcelas de 400 m2 onde todos os indivíduos arbóreos que apresentaram Circunferência a Altura do Peito (CAP, medido a 1,30 m do solo) igual ou superior a 15,7 cm foram medidos, marcados e identificados. As espécies foram classificadas nos grupos sucessionais: pioneira, clímax exigente de luz ou clímax tolerante à sombra. Para a comparação florística com outros remanescentes, foi utilizada a Análise de Correspondência Retificada (DCA). A estrutura do componente arbóreo foi descrita pela densidade, frequência, dominância e Valor de Importância (VI). Os resultados demonstram elevada riqueza florística (98 espécies). Foi possível constatar espécies típicas de FOM, como Araucaria angustifolia (Bert.) Kuntze, e espécies características de FOD, como Byrsonima ligustrifolia A.Juss., confirmando a característica do fragmento estudado de pertencer a uma área de tensão ecológica, padrão confirmado na comparação da similaridade florística. As espécies com maior VI foram Psychotria vellosiana Benth., Alsophila setosa Kaulf. e Guatteria australis A.St.-Hil. Estas e outras espécies de alto VI, por suas consideráveis representatividades na área, são importantes na restauração de florestas ciliares degradadas na região. Os plantios deverão ser planejados obedecendo-se ao grupo sucessional das espécies, plantando-se as espécies pioneiras e clímax exigentes de luz em um primeiro momento (e.g. Psychotria vellosiana), seguidas, quando houver o sombreamento da área, das espécies clímax tolerantes à sombra (e.g. Alsophila setosa e Guatteria australis).The understanding of floristic and structure of tree communities is essential to subside the strategies of forest restoration. In this sense, a phyto-sociological survey was conducted in a forest fragment situated along a tributary of Caeté river, in Alfredo Wagner, state of Santa Catarina, in order to: i) know the structure of trees and flora in this forest, ii) classify the species found according to ecological groups and iii) compare the flora of the study area with other studies in Araucaria forest (FOM), Atlantic Rain Forest (FOD) and the transition area between FOM-FOD of Santa Catarina state. In this fragment, 10 plots of 400 m2 were allocated, where all individual trees with the circumference at breast height (CBH, measured at 1.30 m above the ground) greater than or equal to 15.7 cm were measured, marked and identified. The species were classified into the following succession groups: pioneer, climax light-demanding or climax shade-tolerant. The Rectified Correspondence Analysis (DCA) was used for the floristic comparison. The structure of the tree component was described by the density, frequency, dominance and importance value (VI). The results showed elevated species richness (98 species). It was found typical species of FOM, such as Araucaria angustifolia (Bert.) Kuntze, and species characteristics of FOD such as Byrsonima ligustrifolia A.Juss., confirming the study fragment as an area of ecological tension between FOM and FOD. The species with most elevated VI were Psychotria vellosiana Benth., Alsophila setosa Kaulf. and Guatteria australis A.St.- Hil. The species with elevated VI, for their considerable representation in the area, are important in the restoration of degraded riparian forests in the region. The species seedlings plantation should be planned observing the group successional of each species, planting pioneer and light-demanding climax species first (e.g. Psychotria vellosiana), followed by, after the shading of the area, shade-tolerant species (e.g. Alsophila setosa e Guatteria australis)

Combined dark matter searches towards dwarf spheroidal galaxies with Fermi-LAT, HAWC, H.E.S.S., MAGIC, and VERITAS

Cosmological and astrophysical observations suggest that 85\% of the total matter of the Universe is made of Dark Matter (DM). However, its nature remains one of the most challenging and fundamental open questions of particle physics. Assuming particle DM, this exotic form of matter cannot consist of Standard Model (SM) particles. Many models have been developed to attempt unraveling the nature of DM such as Weakly Interacting Massive Particles (WIMPs), the most favored particle candidates. WIMP annihilations and decay could produce SM particles which in turn hadronize and decay to give SM secondaries such as high energy $\gamma$ rays. In the framework of indirect DM search, observations of promising targets are used to search for signatures of DM annihilation. Among these, the dwarf spheroidal galaxies (dSphs) are commonly favored owing to their expected high DM content and negligible astrophysical background. In this work, we present the very first combination of 20 dSph observations, performed by the Fermi-LAT, HAWC, H.E.S.S., MAGIC, and VERITAS collaborations in order to maximize the sensitivity of DM searches and improve the current results. We use a joint maximum likelihood approach combining each experiment's individual analysis to derive more constraining upper limits on the WIMP DM self-annihilation cross-section as a function of DM particle mass. We present new DM constraints over the widest mass range ever reported, extending from 5 GeV to 100 TeV thanks to the combination of these five different $\gamma$-ray instruments

Chasing Gravitational Waves with the Chereknov Telescope Array

Presented at the 38th International Cosmic Ray Conference (ICRC 2023), 2023 (arXiv:2309.08219)2310.07413International audienceThe detection of gravitational waves from a binary neutron star merger by Advanced LIGO and Advanced Virgo (GW170817), along with the discovery of the electromagnetic counterparts of this gravitational wave event, ushered in a new era of multimessenger astronomy, providing the first direct evidence that BNS mergers are progenitors of short gamma-ray bursts (GRBs). Such events may also produce very-high-energy (VHE, > 100GeV) photons which have yet to be detected in coincidence with a gravitational wave signal. The Cherenkov Telescope Array (CTA) is a next-generation VHE observatory which aims to be indispensable in this search, with an unparalleled sensitivity and ability to slew anywhere on the sky within a few tens of seconds. New observing modes and follow-up strategies are being developed for CTA to rapidly cover localization areas of gravitational wave events that are typically larger than the CTA field of view. This work will evaluate and provide estimations on the expected number of of gravitational wave events that will be observable with CTA, considering both on- and off-axis emission. In addition, we will present and discuss the prospects of potential follow-up strategies with CTA

Chasing Gravitational Waves with the Chereknov Telescope Array

Presented at the 38th International Cosmic Ray Conference (ICRC 2023), 2023 (arXiv:2309.08219)2310.07413International audienceThe detection of gravitational waves from a binary neutron star merger by Advanced LIGO and Advanced Virgo (GW170817), along with the discovery of the electromagnetic counterparts of this gravitational wave event, ushered in a new era of multimessenger astronomy, providing the first direct evidence that BNS mergers are progenitors of short gamma-ray bursts (GRBs). Such events may also produce very-high-energy (VHE, > 100GeV) photons which have yet to be detected in coincidence with a gravitational wave signal. The Cherenkov Telescope Array (CTA) is a next-generation VHE observatory which aims to be indispensable in this search, with an unparalleled sensitivity and ability to slew anywhere on the sky within a few tens of seconds. New observing modes and follow-up strategies are being developed for CTA to rapidly cover localization areas of gravitational wave events that are typically larger than the CTA field of view. This work will evaluate and provide estimations on the expected number of of gravitational wave events that will be observable with CTA, considering both on- and off-axis emission. In addition, we will present and discuss the prospects of potential follow-up strategies with CTA

Performance of a proposed event-type based analysis for the Cherenkov Telescope Array

The Cherenkov Telescope Array (CTA) will be the next-generation observatory in the field of very-high-energy (20 GeV to 300 TeV) gamma-ray astroparticle physics. Classically, data analysis in the field maximizes sensitivity by applying quality cuts on the data acquired. These cuts, optimized using Monte Carlo simulations, select higher quality events from the initial dataset. Subsequent steps of the analysis typically use the surviving events to calculate one set of instrument response functions (IRFs). An alternative approach is the use of event types, as implemented in experiments such as the Fermi-LAT. In this approach, events are divided into sub-samples based on their reconstruction quality, and a set of IRFs is calculated for each sub-sample. The sub-samples are then combined in a joint analysis, treating them as independent observations. This leads to an improvement in performance parameters such as sensitivity, angular and energy resolution. Data loss is reduced since lower quality events are included in the analysis as well, rather than discarded. In this study, machine learning methods will be used to classify events according to their expected angular reconstruction quality. We will report the impact on CTA high-level performance when applying such an event-type classification, compared to the classical procedure

Chasing Gravitational Waves with the Chereknov Telescope Array

Presented at the 38th International Cosmic Ray Conference (ICRC 2023), 2023 (arXiv:2309.08219)2310.07413International audienceThe detection of gravitational waves from a binary neutron star merger by Advanced LIGO and Advanced Virgo (GW170817), along with the discovery of the electromagnetic counterparts of this gravitational wave event, ushered in a new era of multimessenger astronomy, providing the first direct evidence that BNS mergers are progenitors of short gamma-ray bursts (GRBs). Such events may also produce very-high-energy (VHE, > 100GeV) photons which have yet to be detected in coincidence with a gravitational wave signal. The Cherenkov Telescope Array (CTA) is a next-generation VHE observatory which aims to be indispensable in this search, with an unparalleled sensitivity and ability to slew anywhere on the sky within a few tens of seconds. New observing modes and follow-up strategies are being developed for CTA to rapidly cover localization areas of gravitational wave events that are typically larger than the CTA field of view. This work will evaluate and provide estimations on the expected number of of gravitational wave events that will be observable with CTA, considering both on- and off-axis emission. In addition, we will present and discuss the prospects of potential follow-up strategies with CTA