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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Interfer?ncia de plantas daninhas e toler?ncia do pinh?o-manso ao glyphosate / Weed interference and tolerance of Jatropha to glyphosate

OLIVEIRA, Andr? Luiz de 31 July 2014 (has links)
Submitted by Jorge Silva (jorgelmsilva@ufrrj.br) on 2018-09-04T21:21:54Z No. of bitstreams: 1 2014 - Andr? Luiz de Oliveira.pdf: 857028 bytes, checksum: e94cde2004f67a6b7ee99cd28255353f (MD5) / Made available in DSpace on 2018-09-04T21:21:54Z (GMT). No. of bitstreams: 1 2014 - Andr? Luiz de Oliveira.pdf: 857028 bytes, checksum: e94cde2004f67a6b7ee99cd28255353f (MD5) Previous issue date: 2014-07-31 / CNPq / Brazil stands out on the world stage in renewable energy. Among the various sources of raw material for the production of biodiesel, there is jatropha (Jatropha curcas L.). Technical Information management recommendations, chiefly concerning weeds are scarce for culture. The objective of this study was to evaluate the effect of glyphosate on early growth of plants jatropha and evaluate the effect of competition with weeds in the early development of jatropha. Two experiments were conducted under conditions of greenhouse and laboratory belonging to the Federal Rural University of Rio de Janeiro. In the first experiment was an increase in height, dry matter accumulation, increase in stem diameter and leaf area in plants jatropha after glyphosate application (180.0, 360.0, 720.0 and 1440.0 g ha-1) and a control application, in three positions application (whole plant "over the top", middle third and bottom third of the plants) in a completely randomized block design with four replications. In the second experiment, we evaluated increment in height, dry matter accumulation, increase in stem diameter and leaf area in plants of jatropha in competition with weed species. Five weed species (Bidens pilosa L., Mucuna aterrima Piper & Tracy, Urochloa decumbens Stapf, Panicum maximum Jacq. e Commelina benghaliensis L.) transplanted in each pot separately in five densities (1, 2, 3, 4 and 5 plants per pot) were used, containing a plant jatropha, with plus a control where the plant jatropha grown without the presence of competing species in a completely randomized block design with four replications. It was found in experiment 1, the jatropha plants showed more severe intoxication when herbicide application was performed on the whole plant, at a dose of 1,440 g ha-1 of glyphosate. A reduction in the height increment, the increase in stem diameter and leaf area of plants jatropha when applied to 1440 g ha-1 of glyphosate in the whole plant. For other doses and application site there were no significant effects. With the data it can be concluded that jatropha has high tolerance to glyphosate. It was found in experiment 2, the jatropha plants showed a reduction in dry matter accumulation in leaf area and increase in stem diameter, depending on the weed species competing and increasing densities. A reduction in height, stem diameter, leaf area and total dry mass of plants jatropha who knew the species Panicum maximum, the density of 5 plants. It is concluded that jatropha has reduced those parameters when in competition with weeds in early development. / O Brasil se destaca no cen?rio mundial na produ??o de energia renov?vel. Dentre as diversas fontes de mat?ria prima para a produ??o de biodiesel, destaca-se o pinh?o-manso (Jatropha curcas L.). Informa??es t?cnicas sobre recomenda??es de manejo, principalmente referentes aos de plantas daninhas s?o escassas para a cultura. Objetivou-se nesse trabalho, avaliar o efeito de glyphosate no crescimento inicial de plantas de pinh?o-manso bem como o efeito da competi??o com esp?cies daninhas no desenvolvimento inicial da planta. Dois experimentos foram conduzidos em condi??es de casa de vegeta??o e laborat?rio, pertencentes ? Universidade Federal Rural do Rio de Janeiro. No primeiro experimento avaliou-se incremento em altura, ac?mulo de massa seca, incremento em di?metro do caule e ?rea foliar em plantas de pinh?o-manso ap?s aplica??o de glyphosate (180,0; 360,0; 720,0 e 1.440,0 g ha-1) mais uma testemunha sem aplica??o, em tr?s posi??es de aplica??o (planta toda ?over the top?, ter?o m?dio e ter?o inferior das plantas), no delineamento de blocos ao acaso com quatro repeti??es. No segundo experimento, avaliou-se incremento em altura, ac?mulo de massa seca, incremento em di?metro do caule e ?rea foliar em plantas de pinh?o-manso em competi??o com esp?cies de plantas daninhas. Foram utilizadas cinco esp?cies de plantas daninhas (Bidens pilosa L., Mucuna aterrima Piper & Tracy, Urochloa decumbens Stapf, Panicum maximum Jacq. e Commelina benghaliensis L.) transplantadas separadamente em cada vaso em cinco densidades (1; 2; 3; 4 e 5 plantas por vaso), contendo uma planta de pinh?o-manso, com mais um tratamento controle onde a planta de pinh?o-manso cresceu sem a presen?a das esp?cies competidoras, no delineamento de blocos ao acaso com quatro repeti??es. Verificou-se, no experimento 1, que as plantas de pinh?o-manso apresentaram intoxica??o mais severa quando a aplica??o do herbicida foi realizada sobre a planta toda, na dose de 1.440 g ha-1 de glyphosate. Verificou-se redu??o do incremento em altura, do incremento em di?metro de caule e na ?rea foliar de plantas de pinh?o-manso quando a aplicado 1.440 g ha-1 de glyphosate na planta toda. Para as demais doses e local de aplica??o n?o houve efeitos significativos. De posse dos dados pode-se concluir que o pinh?o-manso apresenta elevada toler?ncia ao glyphosate. Verificou-se, no experimento 2, que as plantas de pinh?o-manso apresentaram redu??o em ac?mulo de massa seca, em ?rea foliar e incremento em di?metro do caule, em fun??o das esp?cies daninhas competidoras e das crescentes densidades. Verificou-se redu??o em altura, di?metro de caule, ?rea foliar e massa seca total das plantas de pinh?o-manso que conviveram com a esp?cie Panicum maximum, na densidade de 5 plantas por vaso. Conclui-se que o pinh?o-manso apresenta redu??o nos par?metros analisados quando em competi??o com plantas daninhas no in?cio do desenvolvimento.
2

Ecologia tr?fica de uma comunidade de lagartos da caatinga

Mac?do, Pedro de Farias Capistrano 21 June 2013 (has links)
Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2016-03-03T20:03:21Z No. of bitstreams: 1 PedroDeFariasCapistranoMacedo_DISSERT.pdf: 1029460 bytes, checksum: 4d43c3ed0516d37711c5df52dd573891 (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2016-03-07T23:36:23Z (GMT) No. of bitstreams: 1 PedroDeFariasCapistranoMacedo_DISSERT.pdf: 1029460 bytes, checksum: 4d43c3ed0516d37711c5df52dd573891 (MD5) / Made available in DSpace on 2016-03-07T23:36:23Z (GMT). No. of bitstreams: 1 PedroDeFariasCapistranoMacedo_DISSERT.pdf: 1029460 bytes, checksum: 4d43c3ed0516d37711c5df52dd573891 (MD5) Previous issue date: 2013-06-21 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico - CNPq / A ecologia tr?fica estuda assuntos relacionados ? dieta dos indiv?duos dentro de uma comunidade. A rela??o entre tamanho corporal do predador e o tamanho da presa, a especializa??o individual e a largura de nicho s?o alguns dos assuntos que podem ser explorados por ela. Realizei coletas de lagartos utilizando armadilha de queda, de cola e coleta ativa em um fragmento de Caatinga. As esp?cies mais comuns nesta comunidade foram Tropidurus hispidus, Tropidurus semitaeniatus e Cnemidophorus ocellifer. Incurs?es ? fazenda tamb?m contaram com coletas de invertebrados em cada esta??o para entender como se apresentavam os recursos alimentares dos lagartos nas esta??es coletadas. Procurei responder algumas perguntas: 1) Se haveria rela??o positiva entre a rela??o corporal do predador e da presa da comunidade; 2) Se em diferentes esta??es a rela??o do tamanho corporal do predador e o tamanho m?ximo e/ou m?nimo da presa seria positiva; 3) Se esp?cies com estrat?gias de forrageio distintas teriam rela??o positiva na rela??o tamanho do predador-presa; 4) Se a sazonalidade influenciaria a especializa??o individual na comunidade de lagartos e esp?cies mais comuns; 5) Se a largura do nicho seria influenciada pela sazonalidade; 6) Se indiv?duos com morfologia mais diferentes entre si apresentariam dieta menos similar. Encontrei que houve realmente uma rela??o positiva entre tamanho da presa e do predador, mas inexistente quanto ao tamanho m?nimo das presas; Entre as esta??es a rela??o tamanho dos predadores e presas foi diferente para o tamanho m?ximo e m?nimo, mas foi positivamente relacionado apenas com o tamanho do m?ximo das presas. E as compara??es entre estrat?gias de forrageio diferentes tiveram as inclina??es da reta m?xima e m?nima maiores que zero e diferentes uma da outra; a especializa??o individual n?o foi influenciada pela sazonalidade e a largura de nicho apenas para T. semitaeniatus teve o nicho mais amplo na esta??o seca. Por fim n?o encontrei rela??o negativa significativa entre dissimilaridade morfol?gica e similaridade da dieta. / The trophic ecology studies issues related to the diet of individuals within a community .The relation between the body size of the predator and the prey size, individual specialization and niche breadth are some of the issues that can be discussed by it .I collected the lizards using pitfall trap, glue and active collecting traps in a fragment of Caatinga. The most common species in this community were Tropidurus hispidus, T. semitaeniatus and Cnemidophorus ocellifer. The visits to the farm also relied on collecting invertebrates at each season to understand how the nutritional resources of lizards were presented in each one of them. I tried to answer some questions : 1) If there was a positive relation between body size of the predator and the size of prey of the community ; 2) If in different seasons the relation of body size of the predator and the maximum and/or minimum size of the prey would be positive ; 3) If species with different foraging strategies have positive relation on the size of the predatorprey relation; 4) If the seasonality would influence on the individual expertise of lizards community and more common species; 5) If the breadth of the niche would be influenced by seasonality ; 6) If more individuals with different morphology between them would present less similar diet. I found that there was indeed a positive relationship between size of prey and predator, but nonexistent related to the minimum size of prey; Among the seasons relative size of predators and prey was different for the maximum and minimum size, but was positively related only to the size of the maximum prey. And comparisons between different foraging strategies had the maximum and minimum line inclination greater than zero and different from each other; individual specialization was not influenced by seasonality and the niche breadth was wider in the dry season only to T. semitaeniatus. At last I didn't find a significant negative relationship between morphological dissimilarity and similarity of diet.
3

Colora??o e sele??o sexual em Tropidurus hispidus

Maggi, Bruno de Souza 30 August 2017 (has links)
Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2017-11-22T21:32:18Z No. of bitstreams: 1 BrunoDeSouzaMaggi_TESE.pdf: 1944735 bytes, checksum: 3f8ff31d8a9b2321520912386e5a28f1 (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2017-11-24T22:46:45Z (GMT) No. of bitstreams: 1 BrunoDeSouzaMaggi_TESE.pdf: 1944735 bytes, checksum: 3f8ff31d8a9b2321520912386e5a28f1 (MD5) / Made available in DSpace on 2017-11-24T22:46:45Z (GMT). No. of bitstreams: 1 BrunoDeSouzaMaggi_TESE.pdf: 1944735 bytes, checksum: 3f8ff31d8a9b2321520912386e5a28f1 (MD5) Previous issue date: 2017-08-30 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico (CNPq) / Nesta proposta esperamos resolver as seguintes quest?es: 1. existe diferen?as na colora??o entre machos e f?meas de Tropidurus hispidus? 2. as f?meas utilizam caracter?sticas da colora??o para escolher parceiros? 3. a colora??o dos machos prediz o resultado de disputas em contextos agon?sticos? Tropidurus hispidus Spix (1825) a maior esp?cie do grupo Torquatus. Os lagartos desse g?nero s?o diurnos, extremamente abundantes, heli?filos, forrageadores senta-e-espera, territoriais, ocorrendo predominantemente em forma??es abertas. Utilizamos um espectrofot?metro para mensurar as vari?veis de cor e uma modelagem visual, utilizando os dados de sensibilidade visual do lagarto Podarcis mularis. Estes dados foram usados para responder a primeira quest?o. Para responder as quest?es 2 e 3 realizamos dois experimentos controlados, no qual pareamos os machos pelo tamanho. No primeiro, de escolha dos machos pelas f?meas, dois machos foram colocados em um terr?rio dividido em tr?s partes, cada macho ficava em um compartimento e n?o tinham contato visual entre eles e a f?meas no outro compartimento com total acesso visual aos dois machos. Para o segundo, de intera??es agon?sticas entre machos, os animais foram colocados em um terr?rio durante 30 min e neste per?odo foram registrado todos os comportamento para determinar os vencedores em cada rodada. Primeiramente, as vari?veis de cor foram usadas para diferenciar machos de f?meas. Nossos primeiros resultados mostraram claramente que T. hispidus exibe dicromatismo sexual e que este ? percebido por conspec?fico. Das onze ?reas do corpo usadas para comparar machos e f?meas, nove mostraram diferen?as significativas. Para a regi?o dorsal e cabe?a, o croma vermelho ? a vari?vel que mais discrimina machos de f?meas. J? para a regi?o ventral da coxa, cloaca, flanco, barriga e garganta o brilho ? a que melhor distingue machos de f?meas. Para a base da cauda a matiz ? o que melhor discrimina os sexos?. Ainda, o croma UV na regi?o ventral da base da cauda, tamb?m distingue os sexos. A modelagem visual mostrou que essas diferen?as s?o percebidas por outro lagarto, confirmando os dados de espectrofotometria. No experimento de escolha pelas f?meas a regi?o e a vari?vel que melhor discriminaram escolhidos e n?o escolhidos, foram, respectivamente ventral da coxa e croma 8. Para o experimento de competi??o entre os machos as regi?es barriga e colar, bem como as vari?veis croma azul, 3 e 8, melhor discriminaram vencedores e perdedores. Isso nos mostra que a diferen?a entre machos e f?meas v?o al?m das descritas na literaturas e que a colora??o tem um papel importante na competi??o inter e intrasexual. Com isso esperamos ter contribu?do para uma melhor compreens?o da evolu??o do design do sinal e como agem a sele??o intra- e intersexual neste processo. / In this study our goals were to address the following issues: Are there differences in coloration between males and females of Tropidurus hispidus? Do females use color traits to choose between mates? Does male coloration predict the outcome of agonistic encounters? Tropidurus hispidus Spix (1825), the larger species of the Torquatus group. Tropidurus are diurnal, extremely abundant, heliophiles, sit-and-wait foragers, and territorial lizards occurring predominantly in open areas. We used a spectrophotometer to measure color variables and visual modeling using visual sensitivity data for Podarcis mularis. This data was used to answer the first question. To answer questions 2 and 3 we performed two controlled experiments with size-paired males. First, we conducted a female mate-choice experiment where males were placed in a terraria enclosure with three separated parts. We assigned each male to a compartment in which they did not have mutual visual contact. Next, we assigned females to the third compartment that enabled visual contact to both the males. The second experiment consisted of an agonistic interaction set up where we placed a pair of males in a single terraria enclosure for 30 min. During the experiment period we recorded behavioral displays in order to determine winners of each trial. Separately, we used color variables to differentiate males from females. Our first results clearly showed that T. hispidus exhibits sexual dichromatism and that it is perceived as conspecific. Of the eleven areas of the body used to compare males and females, nine showed significant differences. For the dorsal region and head, the red chroma is the variable that most discriminates males from females. While for the ventral region of the thigh, cloaca, flank, belly and throat the glow is the one that best distinguishes males from females. For the base of the tail the tint better discriminates. The UV chroma in the ventral region of the tail base also distinguishes the sexes. The visual modeling showed that these differences are likely perceived by other lizards, confirming spectrophotometry data. In the experiment of choice by the females the region and the variable that discriminated best chosen and not chosen were respectively thigh ventral and chroma 8. For the competition experiment between the males the belly and collar regions, as well as the blue, 3 And 8 chroma variables, better discriminated winners and losers. This shows us that the difference between males and females goes beyond those described in literatures and that coloring plays an important role in inter and intra-sexual competition. With this we hope to have contributed to a better understanding of the evolution of the signal design and how the intra- and intersexual selection act in this process in T. hispidus.
4

Efeito das caracter?sticas infantis sobre a coopera??o: an?lise ontogen?tica por uma perspectiva evolucionista

Leit?o, Monique Bezerra Paz 18 December 2015 (has links)
Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2016-10-11T22:03:58Z No. of bitstreams: 1 MoniqueBezerraPazLeitao_TESE.pdf: 11056144 bytes, checksum: 978892fd0142f3723b3084ebbd726901 (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2016-10-17T21:24:59Z (GMT) No. of bitstreams: 1 MoniqueBezerraPazLeitao_TESE.pdf: 11056144 bytes, checksum: 978892fd0142f3723b3084ebbd726901 (MD5) / Made available in DSpace on 2016-10-17T21:24:59Z (GMT). No. of bitstreams: 1 MoniqueBezerraPazLeitao_TESE.pdf: 11056144 bytes, checksum: 978892fd0142f3723b3084ebbd726901 (MD5) Previous issue date: 2015-12-18 / Beb?s e crian?as pequenas costumam ser considerados graciosos e despertar muito afeto. A tend?ncia de perceb?-los de modo positivo e a disposi??o em cuidar s?o atribu?das a tra?os f?sicos e comportamentais t?picos de um infante. Em humanos, caracter?sticas faciais como olhos grandes em rela??o ao rosto e cabe?a arredondada s?o importantes est?mulos. Alguns te?ricos defendem que a tend?ncia humana ? coopera??o tem ra?zes em mecanismos que evolu?ram para o cuidado ? prole, entretanto poucos estudos investigam as rela??es entre tra?os infantis, percep??o de fofura e coopera??o. Neste trabalho foram desenvolvidas quatro publica??es. A primeira investigou a influ?ncia da faixa et?ria e sexo na express?o de comportamentos cooperativos e competitivos e na percep??o de infantilidade por parte de indiv?duos mais velhos ao interagir com crian?as pequenas. Participaram 244 sujeitos (120 do sexo feminino) que interagiram em d?ades durante partidas do jogo da velha. Foram testadas as d?ades: Crian?a 4-5 x Crian?a 8-9 anos; Crian?a 4-5 x Adolescente 14-16 anos; Crian?a 4-5 x Adulto 25-35 anos. Crian?as entre 8-9 anos expressaram mais comportamentos competitivos, especialmente d?ades de sexo opostos, e adultos expressaram mais ajuda. Adolescentes e adultos tenderam a avaliar a crian?a pequena como mais fofinha, bonita e ing?nua. Quanto maior a avalia??o de fofura, menos competi??o por parte de crian?as de 8-9 anos e adultos. A segunda publica??o tratou da constru??o e valida??o do Child Neutral Expression Picture Set - CNEPS, um banco de faces composto por imagens de 131 crian?as entre 4-5 anos, com express?o facial neutra. Ap?s a captura, edi??o e normaliza??o, as imagens foram avaliadas por especialistas, sendo em geral consideradas com express?o neutra. A terceira publica??o teve como objetivo medir e relacionar diversos tra?os faciais infantis das imagens de crian?as entre 4-5 anos com a percep??es de fofura, os comportamentos competitivos e cooperativos no jogo dirigidos a estas crian?as por parte de sujeitos de diferentes idades. Os sujeitos e o m?todo foram os mesmos descritos na primeira publica??o, acrescidos da medi??o dos tra?os. O estudo ? inovador por mostrar que a percep??o e frequ?ncia de competi??o e ajuda variam de acordo com a intensidade de certos tra?os em todas as faixas et?rias. Nas crian?as de 8-9 anos, os tra?os relacionaram-se ? percep??o de fofura, nos adolescentes tanto ?s percep??es e como ? inibi??o de competi??o. Nos adultos os tra?os correlacionaram com mais ajuda. A quarta publica??o ? uma nota t?cnica que descreve v?rios bancos de imagens faciais de crian?as e adultos dispon?veis para pesquisas cient?ficas. Em s?ntese, a presente tese mostrou que ao longo do desenvolvimento, os indiv?duos tendem a agir mais cooperativamente com crian?as pequenas e de avali?-las de modo mais positivo e que os tra?os infantis espec?ficos influenciam a diminui??o da competitividade e aumento da coopera??o. Entende-se que diversas adapta??es cognitivas e comportamentais foram favorecidas durante a evolu??o humana para promover cuidado e prote??o de indiv?duos imaturos, especialmente considerando o alto n?vel de depend?ncia e o longo per?odo de cuidado exigido pelos nossos infantes. / Babies and young children are often considered graceful and evoke much affection. The tendency to perceive them in a positive manner and the propensity to care for them are assigned to physical and behavioral traits typical of an infant. In humans, facial features such as large eyes relative to the face and rounded head are important stimuli. Some theorists argue that the human cooperation tendency is rooted in mechanisms that have evolved to care for offspring, however few studies investigated the relationship between children's traits, perceptions of cuteness and cooperation. In this work it was developed four publications. The first investigated the influence of age range and sex in the expression of cooperative and competitive behaviors and perception of childishness on the part of older individuals by interacting with young children. Took part of the study 244 subjects (120 females) who interacted in dyads during tic-tac-toe matches. Dyads tested were: Child 4-5 x Child 8-9 years old; Child 4-5 x Adolescent 14-16 years old; Child 4-5 x Adult 25-35 years old. Children aged 8-9 years expressed more competitive behavior, especially dyads of opposite sex, and adults expressed more help. Adolescents and adults tended to evaluate the young child as cuter, more beautiful and more na?ve. The higher the cuteness evaluation, the lower competition by children aged 8-9 years and adults. The second publication describes the construction and validation of the Child Neutral Expression Picture Set - CNEPS, a database face made up of images of 131 children between 4-5 years old with neutral facial expression. After capturing, editing and standardizing, the images were evaluated by experts, generally being considered with neutral expression. The third publication aimed to measure and correlate the facial infant traits of children's image with positive perceptions, competitive and cooperative behaviors in the game toward these children by subjects of different ages. The subjects and method were the same used in the first publication, adding the traits' measurement. The study is innovative by showing that the perception and frequency of competition and helping vary according to the intensity of certain baby schema traits in all age groups. Among children 8-9 years old the traits correlated to the perception of cuteness, among the adolescents they were related to both the positive perception and competition inhibition. In adults, the traits correlated with more help. The fourth publication is a technical note describing datasets of facial images of children and adults available for scientific research. In summary, this thesis showed that across the lifespan, individuals tend to act more cooperatively with small children, evaluate them more positively and that specific infant traits influence the decreased competitiveness and increased cooperation. It is understood that several cognitive and behavioral adaptations were favored during human evolution to promote care and protection of immature individuals, especially considering the high level of dependency and long-term care required by our infants.
5

Capacidade competitiva, seletividade de herbicidas e atividade microbiana rizosf?rica de mudas de Hymenaea courbaril L.. / Competitive capability, selectivity of herbicides and rhizospheric microbial activity of Hymenaea courbaril L seedling.

Gandini, Elizzandra Marta Martins January 2011 (has links)
Submitted by Rodrigo Martins Cruz (rodrigo.cruz@ufvjm.edu.br) on 2015-02-27T13:30:36Z No. of bitstreams: 5 55.pdf: 569820 bytes, checksum: b67e70762aca5d283f8f7ed1df3d96f0 (MD5) license_url: 52 bytes, checksum: 3d480ae6c91e310daba2020f8787d6f9 (MD5) license_text: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) license_rdf: 23898 bytes, checksum: e363e809996cf46ada20da1accfcd9c7 (MD5) license.txt: 2109 bytes, checksum: aa477231e840f304454a16eb85a9235f (MD5) / Approved for entry into archive by Rodrigo Martins Cruz (rodrigo.cruz@ufvjm.edu.br) on 2015-02-27T19:29:22Z (GMT) No. of bitstreams: 5 55.pdf: 569820 bytes, checksum: b67e70762aca5d283f8f7ed1df3d96f0 (MD5) license_url: 52 bytes, checksum: 3d480ae6c91e310daba2020f8787d6f9 (MD5) license_text: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) license_rdf: 23898 bytes, checksum: e363e809996cf46ada20da1accfcd9c7 (MD5) license.txt: 2109 bytes, checksum: aa477231e840f304454a16eb85a9235f (MD5) / Made available in DSpace on 2015-02-27T19:29:22Z (GMT). No. of bitstreams: 5 55.pdf: 569820 bytes, checksum: b67e70762aca5d283f8f7ed1df3d96f0 (MD5) license_url: 52 bytes, checksum: 3d480ae6c91e310daba2020f8787d6f9 (MD5) license_text: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) license_rdf: 23898 bytes, checksum: e363e809996cf46ada20da1accfcd9c7 (MD5) license.txt: 2109 bytes, checksum: aa477231e840f304454a16eb85a9235f (MD5) Previous issue date: 2011 / O presente estudo teve por objetivo avaliar mudas de Hymenea courbaril L. (jatob?) quanto: (a) ? capacidade competitiva com plantas consortes e esp?cies daninhas referentes a aloca??o de mat?ria seca, ?rea foliar e concentra??o de macronutrientes; (b) ? seletividade aos herbicidas sulfentrazone e glyphosate e; (c) aos efeitos de diferentes doses de sulfentrazone sobre a atividade microbiana de substratos cultivados com as mudas. Os experimentos foram conduzidos em casa-de-vegeta??o, viveiro de produ??o de mudas e em laborat?rio na Universidade Federal dos Vales do Jequitinhonha e Mucuri (UFVJM), Diamantina-MG. No ano de 2009, foram conduzidos dois experimentos sendo os tratamentos compostos pela combina??o de mudas de jatob?, se desenvolvendo isoladamente ou em competi??o com cada uma das seguintes esp?cies Brachiaria humidicola, Brachiaria brizantha, Brachiaria decumbens, Panicum maximum, Cajanus cajan, Canavalia ensiformis e Mucuna aterrima (experimento 1) e Cenchrus echinatus L., Bidens pilosa L., Euphorbia heterophylla L., Solanum americanum Mill e Lolium multiflorum Lam. (experimento 2), mais o cultivo isolado de cada planta daninha e consorte, por 60 dias. Al?m do efeito das plantas nas caracter?sticas de altura e mat?ria seca das plantas de jatob?, avaliou-se o ac?mulo de nitrog?nio, f?sforo e pot?ssio em todas as plantas. Em 2010, tamb?m foram conduzidos dois experimentos sendo os tratamentos compostos por dois herbicidas (glyphosate e sulfentrazone) e cinco doses desses herbicidas (0,00; 0,09; 0,18; 0,35 e 0,70 L ha-1) (experimento 1); cinco doses de sulfentrazone (0,00; 0,04; 0,15; 0,30 e 0,60 L ha-1) e dois tipos de substratos (rizosf?rico e n?o rizosf?rico cultivados com mudas de jatob?) (experimento 2), sendo avaliado o potencial de intoxica??o desses produtos sobre a esp?cie vegetal e a comunidade microbiana rizosf?rica. Observou-se que a competi??o entre as plantas n?o promoveu altera??es na produ??o de mat?ria seca ou ?rea foliar do jatob?. Sobre a conviv?ncia das plantas daninhas com o jatob?, constatou-se efeito positivo no ac?mulo de nutrientes por estas. Os herbicidas estudados apresentaram-se com elevado potencial para uso no controle de plantas daninhas em ?reas de plantios de jatob? em fase inicial de desenvolvimento. Quanto aos indicadores microbiol?gicos, verifica-se que a evolu??o do C-CO2 e o carbono da biomassa microbiana foram sens?veis ? presen?a dos herbicidas podendo constituir ferramentas auxiliares no monitoramento do impacto desses produtos no ambiente. / Disserta??o (Mestrado) ? Programa de P?s-Gradua??o em Produ??o Vegetal, Universidade Federal dos Vales do Jequitinhonha e Mucuri, 2011. / ABSTRACT The objective of this study was to evaluate Hymenaea courbaril L (jatoba) seedling in relation to: a) the competitive capability with intercropped plants and weed regarding to dry matter allocation, leaf area and macronutrients concentration. b) The selectivity of herbicides sulfentrazone and glyphosate and, c) the effects of different doses of sulfentrazone on microbial activity of substrates cultivated with the seedling. The experiments were conducted in greenhouse, nursery and laboratory of UFVJM. In 2009, two experiments were carried out, being the treatments a combination of jatoba seedling that had developed alone and/or in competition with one of the following species: Brachiaria humidicola, Brachiaria brizantha, Brachiaria decumbens, Panicum maximum, Cajanus cajan, Canavalia ensiformis and Mucuna aterrima (experiment 1) and Cenchrus echinatus L., Bidens pilosa L., Euphorbia heterophylla L., Solanum americanum Mill and Lolium multiflorum Lam. (experiment 2), plus the isolated cultivation of every weed and plant that was intercropped for 60 days. Besides the effects of the weed plants on height and dry matter of jatoba plants, it was assessed the accumulation of nitrogen, phosphorus and potassium in all of plants. In 2010, it is also made two experiments and the treatment was made with two herbicides (glyphosate and sulfentrazone) and five doses of these herbicides (0,00; 0,09; 0,18; 0,35 e 0,70 L ha-1) (experiment 1); five doses of sulfentrazone (0,00; 0,04; 0,15; 0,30 e 0,60 L ha-1) and two types of substrates (rhizospheric and non-rhizospheric cultivated with jatoba seeding) (experiment 2). It was assessed the poisoning potential of these products on vegetal species and the rhizospheric microbial community. It was observed that the competition between the plants did not trigger changes on production of dry matter or leaf area of jatoba. It was verified a positive effect of nutrients accumulation by weed that lived together with jatoba. These herbicides have showed high potential for use on weed control in areas of jatoba planting in initial phase of development. Regarding to microbiological indicators, it was verified that the C-CO2 and microbial biomass carbon evolution was sensitive to the presence of herbicides that be constitute auxiliary tools on monitoring of the impact of these products.
6

Parti??o de recursos entre duas esp?cies simp?tricas de Gracilinanus (Didelphimorphia: Didelphidae) em uma ?rea de mata ciliar sav?nica: rela??o com o uso de ambiente e a dieta

Paula, Camilla de Souza 07 August 2017 (has links)
Na Capa, Folha de Rosto e Ficha Catalogr?fica constam o t?tulo: "Parti??o de recursos entre duas esp?cies simp?tricas de Gracilinanus (Didelphimorphia: Didelphidae): rela??o com o uso do espa?o e ecologia alimentar". / Submitted by Jos? Henrique Henrique (jose.neves@ufvjm.edu.br) on 2018-07-03T17:44:50Z No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) camilla_souza_paula.pdf: 1869121 bytes, checksum: 8447fdb830cc6e38dc596372753d5bb8 (MD5) / Approved for entry into archive by Rodrigo Martins Cruz (rodrigo.cruz@ufvjm.edu.br) on 2018-07-18T12:54:35Z (GMT) No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) camilla_souza_paula.pdf: 1869121 bytes, checksum: 8447fdb830cc6e38dc596372753d5bb8 (MD5) / Made available in DSpace on 2018-07-18T12:54:35Z (GMT). No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) camilla_souza_paula.pdf: 1869121 bytes, checksum: 8447fdb830cc6e38dc596372753d5bb8 (MD5) Previous issue date: 2017 / Universidade Federal dos Vales do Jequitinhonha e Mucuri (UFVJM) / Diversas esp?cies de pequenos mam?feros Neotropicais ocorrem em simpatria ao longo de suas ?reas de distribui??o e ? relevante compreender os mecanismos que favorecem a coexist?ncia das esp?cies e que controlam a estrutura da comunidade ecol?gica. O objetivo do presente estudo foi analisar os poss?veis mecanismos de particionamento de recursos entre as esp?cies simp?tricas Gracilinanus agilise G. microtarsus, avaliando o nicho alimentar e o nicho espacial.O estudo foi realizado no per?odo de maio de 2016 a janeiro de 2017 em uma ?rea de mata ciliar sav?nica, no Parque Estadual do Rio Preto, Minas Gerais. Analisamos a dieta das duas esp?cies atrav?s da frequ?ncia de ocorr?ncia dos itens alimentares presentes nas fezes, al?m disso, estudamos o uso do espa?o realizado pelas esp?cies e a rela??o com a heterogeneidade e complexidade ambiental. Analisamos a dieta das duas esp?cies atrav?s da frequ?ncia de ocorr?ncia dos itens alimentares presentes nas fezes. As esp?cies apresentaram uma alta sobreposi??o de nicho no consumo de itens alimentares (CH=0,96), com algumas diferen?as na frequ?ncia de ocorr?ncia dos itens consumidos. Apesar dos itens mais frequentes nas amostras fazer parte da categoria dos invertebrados (Hymenoptera, Isoptera e Coleoptera), a propor??o que esses itens apareceram nas amostras foi diferente para as duas esp?cies, al?m disso, a variedade de itens alimentares tamb?m diferiu entre as esp?cies, onde observamos a presen?a de flores nas amostras de G. agilis, e uma maior variedade de frutos nas amostras de G. microtarsus. Atrav?s das abund?ncias relativas das esp?cies por estrato observamos que ambas utilizam preferencialmente o subbosque, al?m disso, observamos uma segrega??o espacial entre as esp?cies simp?tricas de Gracilinanus, com G. agilis aparentemente ocorrendo mais na borda da mata e, sua cong?nere G. microtarsus, mais no interior da mata. Apesar da alta sobreposi??o de nicho alimentar observada, os resultados indicam que a coexist?ncia das esp?cies simp?tricas estudadas pode estar associada a dois mecanismos: a flexibiliza??o no uso dos itens alimentares e particionamento no uso do espa?o. / Disserta??o (Mestrado) ? Programa de P?s-gradua??o em Biologia Animal, Universidade Federal dos Vales do Jequitinhonha e Mucuri, 2017. / Several species of small Neotropical mammals occur in sympatry throughout their distribution areas and it is relevant to understand the mechanisms that favor the coexistence of the species and that control the structure of the ecological community. The objective of the present study was to analyze the possible mechanisms of partitioning of resources between the sympatric species Gracilinanus agilis and G. microtarsus, evaluating the food niche and the spatial niche. The study was carried out from May 2016 to January 2017 in an area of savanna ciliary forest, in the State Park of Rio Preto, Minas Gerais. We analyzed the diet of the two species through the frequency of occurrence of the food items present in their feces; in addition, we studied the use of the space realized by the species and the relation with the heterogeneity and environmental complexity. The species presented a high niche overlap in the consumption of food items (CH = 0.96), with some differences in the frequency of occurrence of the consumed items. Although the most frequent items in the samples belonged to the category of invertebrates (Hymenoptera, Isoptera and Coleoptera), the proportion that these items appeared in the samples was different for both species. The variety of food items also differed between the species, where the presence of flowers where more observed in the samples of G. agilis, and a greater variety of fruits was observed in the samples of G. microtarsus. The relative abundances of the species per stratum show that both species preferentially use the sub-forest, in addition, we observed a spatial segregation between the sympatric species of Gracilinanus, with G. agilis apparently occurring more at the edge of the forest, and its congener G. microtarsus further into the woods. Despite the high food niche overlap observed, the results indicate that the coexistence of the sympatric species studied may be associated to two mechanisms: flexibility in the use of food items and partitioning in the use of space.
7

Competi??o espacial no mercado de revenda da gasolina: uma an?lise nas principais cidades do Rio Grande do Norte

Braga, Leonardo Gevezier 24 October 2014 (has links)
Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2016-04-25T20:29:03Z No. of bitstreams: 1 LeonardoGevezierBraga_DISSERT.pdf: 641257 bytes, checksum: 9ac37a1f5bff2cba8c95c5c34ebe5305 (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2016-04-26T23:02:20Z (GMT) No. of bitstreams: 1 LeonardoGevezierBraga_DISSERT.pdf: 641257 bytes, checksum: 9ac37a1f5bff2cba8c95c5c34ebe5305 (MD5) / Made available in DSpace on 2016-04-26T23:02:20Z (GMT). No. of bitstreams: 1 LeonardoGevezierBraga_DISSERT.pdf: 641257 bytes, checksum: 9ac37a1f5bff2cba8c95c5c34ebe5305 (MD5) Previous issue date: 2014-10-24 / Este trabalho tem como objetivo analisar a competi??o entre postos de gasolina no Estado do Rio Grande do Norte. Para tanto, investiga-se a rela??o entre o pre?o m?dio da gasolina e a concentra??o de postos nos mercados (munic?pios) do estado do Rio Grande do Norte. Faz-se uso de uma ferramenta pouco aplicada para o mercado brasileiro que ? o modelo econom?trico espacial. Foi utilizada uma base que cont?m dados de todos os postos das principais cidades do estado do Rio Grande do Norte e inclui 142 observa??es referentes a postos. Modelos te?ricos predizem a rela??o entre o n?mero de competidores num mercado e o pre?o m?dio; estes modelos te?ricos compreendem: os de competi??o monopol?stica de Perloff e Salop (1985), e os de search-theoretic, de Carlson e McAfee (1983) e de Varian (1980). Os resultados emp?ricos mostraram que uma maior densidade dentro de um espa?o geogr?fico est? associada a um pre?o m?dio mais baixo, convergindo assim, com o modelo de competi??o monopol?stica e com o search-theoretic de Carlson e McAfee (1983). Os par?metros estimados pouco variaram com inclus?o/exclus?o de vari?veis controles, mostrando a robustez dos mesmos. / This study aims to analyze the relationship between average price with the concentration in the markets (municipalities) in the state of Rio Grande do Norte, is using a little tool applied to the Brazilian market is the spatial econometric model. A data base contains all the stations of the major cities in the state of Rio Grande do Norte and includes 142 observations on stations was used. Theoretical models predict the relationship between the number of competitors in a market and the average price; these theoretical models include: the monopolistic competition of Perloff and Salop (1985), and the search-theoretic, of Carlson and McAfee (1983) and Varian (1980). The empirical results showed that a higher density within a geographic area is associated with a lower average price, thus converging with the monopolistic competition model and with the search-theoretic of Carlson and McAfee (1983). The parameters varied little with the inclusion / exclusion of control variables, showing the robustness of them.
8

Hierarquia social e sucesso alimentar em callithrix jacchus (Primates, Callithrichidae), sob condi??es naturais

Dias, Derlan Angelim 21 September 2007 (has links)
Made available in DSpace on 2014-12-17T15:36:51Z (GMT). No. of bitstreams: 1 DerlanAD.pdf: 578623 bytes, checksum: b1a56f1bf9e153912c46dc26566e416e (MD5) Previous issue date: 2007-09-21 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / The competition for resources is one of the costs of group living. The scramble competition is considered an indirect type of competition, mainly associated with factors like group size and distribution of resources. Contest competition occurs when individuals compete directly for resources. In species that exibit this type of competition the establishment of dominance hierarchy can occur, resulting in differences on feeding and reproductive benefits for each member of the group. In these cases, aggressive and submissive behaviors are expected as a way to signal social status. The aim of this study was to investigate the effects of social hierarchy over food ingestion in Callithrix jacchus. Data recording was from September/2006 to March/2007, eight days by month, at Floresta Nacional de A?u do Instituto Chico Mendes de Biodiversidade. The observation time started at 05:00 AM and finished after the last animal was on the sleeptree. Analyses of aggressive interactions, behavioral profile and diet, reveals a lot of advantages for dominat animals in the study group. Dominant individuals had higher intake of animal matter that subordinates. The last ones, consumed fruits, exsudate and, eventually, explored itens that were not common to the diet. We suggest that dominance hiearchy enable the reproductive female to assure priority on access to food resources, a important caracteristc to supply tha costs to maintain tha high reproductive taxa of the specie. We also suggest that reproductive male, due to the participation on food transfer, had the forage efficience reduced / A vida em grupo implica em competi??o por recursos entre os indiv?duos. Competi??o do tipo Scramble ? considerada um modo indireto de competi??o, associado principalmente a fatores como tamanho do grupo e distribui??o dos recursos no ambiente. Competi??o do tipo Contest ocorre quando indiv?duos competem diretamente por recursos. Em esp?cies sujeitas a esse modo de competi??o pode ocorrer estabelecimento de hierarquia de domin?ncia, resultando em diferen?as nos benef?cios obtidos pelos indiv?duos no ?mbito alimentar e reprodutivo. Intera??es agressivas, bem como exibi??es de submiss?o, s?o esperadas como forma de sinalizar status social. Neste estudo investigamos o modo como a hierarquia social atua sobre o sucesso alimentar em Callithrix jacchus. De setembro de 2006 a mar?o de 2007 observamos um grupo selvagem de sag?is na Floresta Nacional de A?u do Instituto Chico Mendes de Biodiversidade, 8 dias por m?s. As observa??es tinham inicio ?s 05:00 e t?rmino ap?s todos os indiv?duos se recolherem ? ?rvore de dormir. A coleta de dados foi realizada atrav?s da t?cnica animal focal com registro instant?neo a cada minuto, durante 15 minutos consecutivos. Analisando as intera??es agon?sticas, perfil comportamental e perfil alimentar do grupo, verificamos que a hierarquia social em C. jacchus, al?m dos benef?cios reprodutivos, tamb?m confere uma s?rie de vantagens no ?mbito alimentar ao casal reprodutor. Em nosso estudo, intera??es agressivas, incluindo persegui??es, arranh?es e mordidas, foram pouco freq?entes de modo intragrupo. As rela??es de domin?ncia, portanto, foram mais evidentes atrav?s de comportamentos de submiss?o. N?o constatamos diferen?as significativas entre os animais em rela??o ? taxa de ingest?o total. Todavia, a an?lise do perfil alimentar (propor??o de mat?ria animal e vegetal na dieta) revelou que dominantes asseguraram maior ingest?o de mat?ria animal, enquanto subordinados utilizaram frutos, exsudado e, eventualmente, exploraram itens que n?o eram comuns ? dieta. Sugerimos que atrav?s da hierarquia social, a f?mea reprodutora assegura acesso preferencial a recursos alimentares, sendo esta uma importante caracter?stica para suprir os custos envolvidos com a manuten??o da alta taxa reprodutiva verificada para a esp?cie. O macho reprodutor, apesar de tamb?m assegurar acesso a recursos, tem sua efici?ncia de forrageio reduzida devido ? participa??o na partilha de alimentos direcionada aos filhotes
9

Constrained coalition formation among heterogeneous agents for the multi-agent programming contest

Rodrigues, Tabajara Krausburg 26 March 2018 (has links)
Submitted by PPG Ci?ncia da Computa??o (ppgcc@pucrs.br) on 2018-05-28T12:31:15Z No. of bitstreams: 1 TABAJARA_KRAUSBURG_RODRIGUES_DIS.pdf: 4049392 bytes, checksum: 154302eff9df959cfa74d6c0faec5d4e (MD5) / Approved for entry into archive by Sheila Dias (sheila.dias@pucrs.br) on 2018-06-06T13:05:51Z (GMT) No. of bitstreams: 1 TABAJARA_KRAUSBURG_RODRIGUES_DIS.pdf: 4049392 bytes, checksum: 154302eff9df959cfa74d6c0faec5d4e (MD5) / Made available in DSpace on 2018-06-06T13:35:29Z (GMT). No. of bitstreams: 1 TABAJARA_KRAUSBURG_RODRIGUES_DIS.pdf: 4049392 bytes, checksum: 154302eff9df959cfa74d6c0faec5d4e (MD5) Previous issue date: 2018-03-26 / Esta disserta??o apresenta um estudo sobre forma??o de coaliz?es entre agentes heterog?neos para a competi??o de programa??o multiagente de 2017. Foi investigado e aplicado a forma??o de estruturas de coaliz?es entre agentes para resolver problemas log?sticos simulados sobre o mapa de uma cidade real. A fim de atingir o objetivo deste trabalho, foram integrados algoritmos formadores de coaliz?es na plataforma JaCaMo por meio de um artefato CArtAgO chamado CFArtefact. Foi utilizada a implementa??o provida pelo time SMART-JaCaMo (time participante da competi??o multiagente), para experimentar a forma??o de coaliz?es na competi??o. Tr?s abordagens foram avaliadas no dom?nio da competi??o em diferentes configura??es. A primeira abordagem utiliza somente aloca??o de tarefas para resolver o problema. A segunda e a terceira abordagem utilizam a t?cnica de forma??o de coaliz?es anteriormente ? aloca??o de tarefas; dentre estas abordagens, uma utiliza um algor?timo ?timo para resolver o problema e a outra um heur?stico. As an?lises dos experimentos realizados mostram que algor?timos formadores de coaliz?es podem melhorar a performance do time participante da competi??o quando a taxa de trabalhos gerados pelo simulador ? baixa. Entretanto, conforme a taxa de trabalhos aumenta, a abordagem que realiza somente aloca??o de tarefas obt?m um desempenho melhor quando comparada as demais. Mesmo a abordagem heur?stica tem desempenho pr?ximo ? abordagem ?tima para coaliz?es. Desta forma, ? poss?vel concluir que forma??o de coaliz?es possui grande valia para balancear os agentes para um conjunto de trabalhos que precisa ser completado. / This work focuses on coalition formation among heterogeneous agents for the 2017 multiagent programming contest. An agent is a computer system that is capable of independent action to achieve its goals. In order to increase the effectiveness of the agents, we can organise them into coalitions, in which the agents collaborate with each other to achieve individual or common goals. We investigate and apply coalition structure generation (the first activity of the coalition formation process) in simulated scenarios, specifically the 2017 contest scenario, where the agents forming a competing team cooperate to solve logistic problems simulated on the map of a real city. In order to achieve our goal, we integrate coalition formation algorithms into the JaCaMo platform by means of a CArtAgO artefact, named CFArtefact. We use the implementation of the SMART JaCaMo team for experimenting with the coalition formation approach in the contest scenario. We experiment on three approaches in the contest domain with different configurations. In the first, we use only a taskallocation mechanism, while the other approaches use an optimal coalition formation algorithm and a heuristic coalition formation algorithm. We conducted several experiments to compare the advantages of each approach. Our results show that coalition formation algorithms can improve the performance of a participating team when dealing with low job rates (i.e., how quickly new jobs are created by the simulation). However, as we increase the job rate, the approach using only task allocation has better performance. Even a heuristic coalition formation approach has close performance to the optimal one in that case. Coalition formation can play an important role when we aim to balance each group of agents to accomplish some particular goal given a larger team of cooperating agents.
10

Padr?es de coexist?ncia e utiliza??o do h?bitat por duas esp?cies de Herpsilochmus (Aves: Thamnophilidae)

Fran?a, Karol Lyncoln B. de O. de 05 July 2012 (has links)
Made available in DSpace on 2014-12-17T14:33:09Z (GMT). No. of bitstreams: 1 KarolLBOF_DISSERT_PARCIAL.pdf: 340660 bytes, checksum: f2a188d52831a6a40d06910a31049e94 (MD5) Previous issue date: 2012-07-05 / How ecologically similar species are able to coexist has always generated great interest in the scientific community. Classical niche theory predicts that species coexistence is only possible when they segregate in at least one dimension of the ecological niche, thus leading to ecological differentiation among species. However, recent work has shown that species that are more similar in some ecological traits are the ones more prone to be able to coexist (environmental filter). The knowledge of how these forces act shaping ecological communities can reveal co-existence strategies, providing important information for management and conservation of the species. This study tested these hypotheses using a pair of coexisting species of Herpsilochmus, H. pectoralis and H. sellowi. In this study I use high resolution (50 x 50 m) ecological niche models to Identify which environmental factors best predict species occurrence. Next, I calculate the overlap in habitat use by species and build null models to test the hypothesis of spatial niche segregation. In addition, I obtain the selectivity parameters of habitat use to test whether the species H. pectoralis (larger body size) is less selective than H. sellowi (smaller body size) as stated in the literature for other species. The results reject the ecological equivalence among species, revealing that the species of Herpsilochmus explore the habitat differently, having different environmental niches. The hypothesis of environmental filter was not observed in my analysis, the observed overlap in habitat use among species was lower than expected by chance. Evidence that Herpsilochmus are spatially segregating reinforces the hypothesis of interspecific competition as the predominant force in the selection of microhabitat of the species. However, more data and experiments are necessary to state categorically that the observed pattern is a result of current or past competition / Como esp?cies similares ecologicamente s?o capazes de coexistir sempre gerou grande interesse na comunidade cient?fica. A teoria cl?ssica de nicho prev? que para que a coexist?ncia seja poss?vel as esp?cies devem segregar em alguma dimens?o do nicho ecol?gico, portanto levando a diferencia??o entre as esp?cies. No entanto, trabalhos recentes tem demonstrado que justamente esp?cies mais similares em algumas caracter?sticas ecol?gicas seriam mais capazes de coexistir (filtro ambiental). O conhecimento de como essas for?as atuam nas comunidades pode revelar estrat?gias de coexist?ncia, trazendo importantes informa??es para o manejo e conserva??o das esp?cies. Neste estudo testei essas hip?teses de coexist?ncia utilizando o par de esp?cies Herpsilochmus pectoralis e H. sellowi. Para isso utilizei modelos de nicho ecol?gico em alta resolu??o (50 x50 m).Identifiquei quais os fatores ambientais estudados melhor predizem a ocorr?ncia das esp?cies. Em seguida, calculei a sobreposi??o no uso de h?bitat pelas esp?cies e constru? modelos nulos para testar a hip?tese de segrega??o de nicho espacial. Ainda, calculei par?metros de seletividade do uso do h?bitat para testar se a esp?cie H. pectoralis (esp?cie de maior tamanho de corpo) ? menos seletiva que o H. sellowi (esp?cie de menor tamanho de corpo) como previsto na literatura para outras esp?cies.Os resultados rejeitam a equival?ncia ecol?gica entre as esp?cies, revelando que as esp?cies de Herpsilochmus exploram o habitat de forma diferenciada, possuindo nichos ambientais distintos. A hip?tese de filtro ambiental n?o foi evidenciada em nossas an?lises, sendo a sobreposi??o no uso do h?bitat observada entre as esp?cies menor do que o esperado ao acaso. Evid?ncias de que os Herpsilochmus est?o segregando espacialmente refor?a a hip?tese da competi??o interespec?fica como for?a predominante na sele??o de microh?bitat das esp?cies. No entanto, para afirmar categoricamente que o padr?o observado ? efeito de uma competi??o atual ou passada experimentos futuros s?o sugeridos

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