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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

Cave Structure and Cave Faunal Diversity in Kenting Area

Huang, Chih-Yuan 01 August 2000 (has links)
For the purpose to understand the diversity, distribution and abundance of faunas, and to determine the variables that would influence the faunal diversity in caves and tunnels, observations and records had been made during September 1999 to June 2000 in Kenting area, the southern tip of Taiwan. A total number of 19 caves and 2 tunnels were studied. Among them, 4 caves are located in the forest recreation area, 15 caves in the natural preserved area, 1 tunnel in Guanshan village and another tunnel in Mt. Dayuan area. All the faunal species included 3 species of Malacostraca, 2 species of Arachnida, 2 species of Chilopoda, 3 species of Insecta, 3 species of Amphibia, 3 species of Reptilia and 7 species of Mammalia. Among these fauna species, the crickets (Ceuthophilus maculatus), the spiders (Heteropoda venatoria) and the ants (Polyrhachis sp.) had a widely distribution and are the most common species in caves and tunnels. Among all the continuous structural variables of caves and tunnels, the entrance height (r=-0.47) and the entrance area (r=-0.48) had a negative correlation with Shannon-Wiener¡¦s diversity (p<0.05). On the other hand, the total length (r=0.48) and the length of dark zone (r=0.52) had a positive correlation with diversity (p<0.05). In addition, the height of the dark zone had a negative correlation (r=-0.53, p<0.05) with evenness. Among the categorical descriptive variables, human disturbance and multiple chambers had a significant difference with Shannon-Wiener¡¦s diversity (P<0.05). The caves or tunnels visited by people from 2 to 4 times per month had the highest values of diversity, and the caves or tunnels visited by people more than 4 times per month had the lowest values of diversity. In addition, the values of diversity in caves and tunnels with multiple chambers were higher than the ones in caves and tunnels without multiple chambers.
2

Padrões morfológico-evolutivos em espécies subterrâneas de Ituglanis Costa &amp; Bockmann, 1993 (Siluriformes: Trichomycteridae) / Morphological-evolutionary patterns in subterranean species of Ituglanis Costa & Bockmann, 1993 (Siluriformes: Trichomycteridae)

Rizzato, Pedro Pereira 05 June 2014 (has links)
Um dos principais objetivos da Biologia Subterrânea é identificar e entender as modificações morfológicas apresentadas pelos organismos subterrâneos que podem ser relacionadas a seu modo de vida. No presente trabalho, realizamos essa investigação utilizando como modelo as espécies subterrâneas de Ituglanis Costa & Bockmann, 1993 (Siluriformes: Trihomycteridae). Atualmente são conhecidas sete espécies subterrâneas do gênero, as quais se distribuem em regiões geográficas muito próximas entre si, as áreas cársticas de São Domingos e de Mambaí e Posse, no nordeste do estado de Goiás. Analisamos caracteres externos (tamanho e alonga-mento corporal, nadadeiras pares e pigmentação) e sensoriais (olhos, barbilhões, sistema láte-rosensorial e encéfalo), e identificamos tendências de modificação em todos eles. As espécies subterrâneas de Ituglanis tendem a apresentar: alongamento do corpo e, nas espécies que tran-sitam ou ocupam espaços confinados, redução do tamanho corporal; nadadeiras peitorais mais longas e com mais raios, e as pélvicas reduzidas; pigmentação reduzida, os cromatóforos me-nos abundantes e com formas irregulares; olhos menores, deformados, assimétricos e encober-tos por pele; barbilhões bem desenvolvidos, os maxilares mais longos; sistema láterosensorial de canais fragmentado e reduzido, com grande variabilidade e assimetria; e o encéfalo com lobos vagais e faciais desenvolvidos, lobos ópticos reduzidos e aumento do tamanho do cere-belo, da bexiga natatória e dos canais semicirculares do ouvido interno. Muitas dessas caracte-rísticas já haviam sido observadas em espécies subterrâneas de outros grupos de peixes, suge-rindo que elas de fato estejam relacionadas a esse modo de vida. Nem todas as espécies sub-terrâneas de Ituglanis apresentam todas as características em um mesmo grau, de forma que é possível dividi-las entre as menos troglomórficas, Ituglanis sp. 1 e I. mambai, as intermediá-rias, Ituglanis sp. 2 e I. bambui, e as mais troglomórficas, I. passensis, I. ramiroi e I. epikars-ticus. A grande variabilidade tanto intra- quanto interespecífica sugere que essas característi-cas evoluem em mosaico, corroborando hipóteses anteriores de colonização independente do ambiente subterrâneo por cada uma das espécies. As modificações identificadas podem ser divididas em progressivas e regressivas, e discutimos os mecanismos evolutivos que explicam seu surgimento nas espécies subterrâneas. A evolução de características que conferem vanta- gem evolutiva é explicada por mecanismos de seleção natural direta, enquanto que os caracte-res regressivos que não apresentam vantagem ou desvantagem óbvia se encaixam em cenários de evolução neutra. Algumas das características das espécies subterrâneas são típicas de indi-víduos em estágios iniciais de desenvolvimento, o que sugere que a heterocronia pode ter um papel importante na evolução do troglomorfismo. Além disso, a linhagem a que pertencem as espécies subterrâneas apresenta características consideradas preaptativas para o modo de vida subterrâneo, o que favoreceria o desenvolvimento desse modo de vida repetidas vezes na fa-mília Trichomycteridae e, mais especificamente, no gênero Ituglanis. / One of the main objectives of Subterranean Biology is to identify and understand the morpho-logical modifications exhibited by subterranean organisms which can be related to their hypogean life habit. In the present work, we performed this investigation using as model the subterranean species of Ituglanis Costa & Bockmann, 1993 (Siluriformes: Trihomycteridae). Nowadays, seven subterranean species of the genus are recognized, distributed in close geo-graphic regions, the São Domingos karstic area and the Mambaí and Posse karstic area, both on northeastern Goias state, Brazil. We analyzed external (body size and elongation, paired fins and pigmentation) and sensorial characters (eyes, barbels, laterosensory system and brain), and identified tendencies of modification in all of them. Subterranean species of Ituglanis tend to shown: body elongation, and those species occupying confined spaces, body-size reduction; longer pectoral fins, with increased number of rays, and pelvic fins reduced; reduced pigmentation, the cromatophores less numerous and with irregular forms; smaller, deformed and asymmetric eyes, covered by skin; well developed barbels, the maxillary long-er; the canals of the laterosensory system fragmented and reduced, with variability and asymmetry; and the brain with well developed vagal and facial lobes, reduced optic lobes and increased cerebellum, swim bladder and semicircular canals of the inner ear. Many of these characters were already reported for subterranean fishes of other groups, suggesting a rela-tionship with this life habit. The subterranean species of Ituglanis does not exhibit all the characters on the same degree, in such a way that it is possible to classify them as the less troglomorphic, Ituglanis sp. 1 and I. mambai, the intermediary, Ituglanis sp. 2 and I. mambai, and the most troglomorphic, I. passensis, I. ramiroi and I. epikarsticus. The large inter- and intraspecific variability observed suggests a mosaic of evolution for these characters, corrobo-rating previous hypothesis of independent colonization of the subterranean environment in each species. The modifications identified can be divided in progressive and regressive, and we discuss the evolutionary mechanisms that explain their origin. The evolution of characters that can be evolutively advantageous is explained by mechanisms of direct natural selection, whilst regressive characters that do not provide any obvious advantage os disadvantage fit to scenarios of neutral evolution. Some of the characters observed in the subterranean species are typical of individuals in early stages of development, suggesting that heterocrony can play an important role in the evolution of troglomorphism. Furthermore, the lineage to which the subterranean species belong exhibit some characters considered preadaptative for the subter-ranean life habit, favouring its development repeatedly in the family Trichomycteridae and, more specifically, in the genus Ituglanis.
3

Padrões morfológico-evolutivos em espécies subterrâneas de Ituglanis Costa &amp; Bockmann, 1993 (Siluriformes: Trichomycteridae) / Morphological-evolutionary patterns in subterranean species of Ituglanis Costa & Bockmann, 1993 (Siluriformes: Trichomycteridae)

Pedro Pereira Rizzato 05 June 2014 (has links)
Um dos principais objetivos da Biologia Subterrânea é identificar e entender as modificações morfológicas apresentadas pelos organismos subterrâneos que podem ser relacionadas a seu modo de vida. No presente trabalho, realizamos essa investigação utilizando como modelo as espécies subterrâneas de Ituglanis Costa & Bockmann, 1993 (Siluriformes: Trihomycteridae). Atualmente são conhecidas sete espécies subterrâneas do gênero, as quais se distribuem em regiões geográficas muito próximas entre si, as áreas cársticas de São Domingos e de Mambaí e Posse, no nordeste do estado de Goiás. Analisamos caracteres externos (tamanho e alonga-mento corporal, nadadeiras pares e pigmentação) e sensoriais (olhos, barbilhões, sistema láte-rosensorial e encéfalo), e identificamos tendências de modificação em todos eles. As espécies subterrâneas de Ituglanis tendem a apresentar: alongamento do corpo e, nas espécies que tran-sitam ou ocupam espaços confinados, redução do tamanho corporal; nadadeiras peitorais mais longas e com mais raios, e as pélvicas reduzidas; pigmentação reduzida, os cromatóforos me-nos abundantes e com formas irregulares; olhos menores, deformados, assimétricos e encober-tos por pele; barbilhões bem desenvolvidos, os maxilares mais longos; sistema láterosensorial de canais fragmentado e reduzido, com grande variabilidade e assimetria; e o encéfalo com lobos vagais e faciais desenvolvidos, lobos ópticos reduzidos e aumento do tamanho do cere-belo, da bexiga natatória e dos canais semicirculares do ouvido interno. Muitas dessas caracte-rísticas já haviam sido observadas em espécies subterrâneas de outros grupos de peixes, suge-rindo que elas de fato estejam relacionadas a esse modo de vida. Nem todas as espécies sub-terrâneas de Ituglanis apresentam todas as características em um mesmo grau, de forma que é possível dividi-las entre as menos troglomórficas, Ituglanis sp. 1 e I. mambai, as intermediá-rias, Ituglanis sp. 2 e I. bambui, e as mais troglomórficas, I. passensis, I. ramiroi e I. epikars-ticus. A grande variabilidade tanto intra- quanto interespecífica sugere que essas característi-cas evoluem em mosaico, corroborando hipóteses anteriores de colonização independente do ambiente subterrâneo por cada uma das espécies. As modificações identificadas podem ser divididas em progressivas e regressivas, e discutimos os mecanismos evolutivos que explicam seu surgimento nas espécies subterrâneas. A evolução de características que conferem vanta- gem evolutiva é explicada por mecanismos de seleção natural direta, enquanto que os caracte-res regressivos que não apresentam vantagem ou desvantagem óbvia se encaixam em cenários de evolução neutra. Algumas das características das espécies subterrâneas são típicas de indi-víduos em estágios iniciais de desenvolvimento, o que sugere que a heterocronia pode ter um papel importante na evolução do troglomorfismo. Além disso, a linhagem a que pertencem as espécies subterrâneas apresenta características consideradas preaptativas para o modo de vida subterrâneo, o que favoreceria o desenvolvimento desse modo de vida repetidas vezes na fa-mília Trichomycteridae e, mais especificamente, no gênero Ituglanis. / One of the main objectives of Subterranean Biology is to identify and understand the morpho-logical modifications exhibited by subterranean organisms which can be related to their hypogean life habit. In the present work, we performed this investigation using as model the subterranean species of Ituglanis Costa & Bockmann, 1993 (Siluriformes: Trihomycteridae). Nowadays, seven subterranean species of the genus are recognized, distributed in close geo-graphic regions, the São Domingos karstic area and the Mambaí and Posse karstic area, both on northeastern Goias state, Brazil. We analyzed external (body size and elongation, paired fins and pigmentation) and sensorial characters (eyes, barbels, laterosensory system and brain), and identified tendencies of modification in all of them. Subterranean species of Ituglanis tend to shown: body elongation, and those species occupying confined spaces, body-size reduction; longer pectoral fins, with increased number of rays, and pelvic fins reduced; reduced pigmentation, the cromatophores less numerous and with irregular forms; smaller, deformed and asymmetric eyes, covered by skin; well developed barbels, the maxillary long-er; the canals of the laterosensory system fragmented and reduced, with variability and asymmetry; and the brain with well developed vagal and facial lobes, reduced optic lobes and increased cerebellum, swim bladder and semicircular canals of the inner ear. Many of these characters were already reported for subterranean fishes of other groups, suggesting a rela-tionship with this life habit. The subterranean species of Ituglanis does not exhibit all the characters on the same degree, in such a way that it is possible to classify them as the less troglomorphic, Ituglanis sp. 1 and I. mambai, the intermediary, Ituglanis sp. 2 and I. mambai, and the most troglomorphic, I. passensis, I. ramiroi and I. epikarsticus. The large inter- and intraspecific variability observed suggests a mosaic of evolution for these characters, corrobo-rating previous hypothesis of independent colonization of the subterranean environment in each species. The modifications identified can be divided in progressive and regressive, and we discuss the evolutionary mechanisms that explain their origin. The evolution of characters that can be evolutively advantageous is explained by mechanisms of direct natural selection, whilst regressive characters that do not provide any obvious advantage os disadvantage fit to scenarios of neutral evolution. Some of the characters observed in the subterranean species are typical of individuals in early stages of development, suggesting that heterocrony can play an important role in the evolution of troglomorphism. Furthermore, the lineage to which the subterranean species belong exhibit some characters considered preadaptative for the subter-ranean life habit, favouring its development repeatedly in the family Trichomycteridae and, more specifically, in the genus Ituglanis.
4

Phylogeography of Darlingtonea Kentuckensis and Molecular Systematics of Kentucky Cave Trechines

Boyd, Olivia Frances 01 May 2015 (has links)
The monotypic cave carabid genus Darlingtonea is widely distributed along the eastern band of the Mississippian/Pennyroyal plateau in Kentucky and northern Tennessee. DNA sequence data from the mitochondrial gene cytochrome oxidase subunit I (COI) was collected from one to four individuals from 27 populations, and patterns of phylogeography and population structure were inferred from COI haplotypes. A hierarchical analysis of molecular variance found low nucleotide diversity within populations and statistically significant variation among geographically-defined groups tested based on two a priori hypotheses of structure. Population structure among five distinct genetic clusters identifies approximate locations of barriers to gene flow among closely grouped caves in the upper Rockcastle River drainage. Partial sequences of one mitochondrial (COI) and one nuclear (wingless) gene were gathered from 60 to 106 terminal taxa, including representatives of all five genera of cave trechines from Kentucky and Tennessee. Alignments were analyzed using maximum parsimony, Bayesian, and maximum likelihood methods of phylogenetic inference. Comparison of analyses demonstrates conflicting tree topologies among individual markers and different reconstruction methods. Despite a lack of consensus regarding genus-level relationships, most analyses supported each genus as natural (monophyletic) with the exception of Pseudanophthalmus
5

Evolution, adaptation and speciation in Anthroherpon Reitter, a genus of subterranean Coleoptera / Evolution, adaptation et speciation chez Anthroherpon Reitter, un genre de coléoptères souterrains

Njunjic, Iva 14 December 2016 (has links)
Cette thèse traite de l’évolution, de l’adaptation et de la spéciation en milieu souterrain, en utilisant le genre Anthroherpon comme modèle. Ce genre appartient à la tribu des Leptodirini (Leiodidae Cholevinae), un groupe qui a connu une remarquable diversification dans le domaine souterrain. Toutes ses espèces ont développé des modifications troglomorphiques spectaculaires: anophthamie, aptérisme, élongation extrême des appendices, de la tête et du pronotum, et physogastrie. Pour comprendre l’histoire évolutive du groupe, ces adaptations troglomorphiques ont été replacées dans un cadre phylogénétique. La thèse est une analyse de la radiation évolutive des Anthroherpon, dans le cadre d’une phylogénie moléculaire datée, qui a permis de mieux comprendre les modalités de diversification du genre, de reconstruire son aire de distribution ancestrale, d’explorer la diversité des évolutions troglomorphiques en son sein et de proposer une nouvelle structure taxonomique du groupe. / The PhD research project focus on the study of evolution, adaptation, and speciation in the subterranean environment using troglobitic Coleoptera of the genus Anthroherpon as a model. Genus Anthroherpon belongs to the tribe Leptodirini (Coleoptera: Leiodidae: Cholevinae), a group that has undergone extensive diversification in the subterranean environment. All species of this genus have developed typical troglomorphic modifications: complete anophthalmy, apterism, extreme elongation of appendages, head, and pronotum, and physogastric elytra. To understand the evolutionary history of this group, the troglomorphic adaptations need to be studied in a phylogenetic framework. The thesis provide a comprehensive evolutionary analysis of the Anthroherpon radiation, using a dated molecular phylogeny as framework for understanding Anthroherpon diversification, reconstructing the ancestral range, and exploring troglomorphic diversity. In light of these findings, a new taxonomical organisation of the group has been proposed.
6

Evolution, adaptation and speciation in Anthroherpon Reitter, a genus of subterranean Coleoptera / Evolucija,adaptacija i specijacija visoko evoluiranih pećinskih koleoptera roda Anthroherpon Reitter

Njunjić Iva 14 December 2016 (has links)
<p>The PhD research project focus on the study of evolution, adaptation, and speciation in<br />the subterranean environment using troglobitic Coleoptera of the genus Anthroherpon<br />as a model organism. Genus Anthroherpon belongs to the tribe Leptodirini (Coleoptera:<br />Leiodidae: Cholevinae), a group that has undergone extensive diversification in the<br />subterranean environment. All species of this genus have developed typical<br />troglomorphic modifications: complete anophthalmy, apterism, extreme elongation of<br />appendages, head, and pronotum, and physogastric elytra. To understand the<br />evolutionary history of this group, the troglomorphic adaptations need to be studied in<br />a phylogenetic framework. The thesis provide a comprehensive evolutionary analysis<br />of the Anthroherpon radiation, using a dated molecular phylogeny as a framework for<br />understanding Anthroherpon diversification, reconstructing the ancestral range, and<br />exploring troglomorphic diversity. In light of these findings, a new taxonomical<br />organisation of the group has been proposed.</p> / <p>Doktorska disertacija predstavlja studiju evolucije, adaptacije i specijacije u<br />podzemnim stani&scaron;tima troglobiontnih tvrdokrilaca roda <em>Anthroherpon</em>. Pomenuti rod<br />pripada tribusu Leptodirini (Leiodidae, Cholevinae), grupi koja je pro&scaron;la intenzivnu<br />diverzifikaciju u uslovima podzemnih stani&scaron;ta. Sve vrste pomenutog roda poseduju<br />tipične troglomorfne osobine, kao &scaron;to su: anoftalmija, apterizam, ekstremno izduženi<br />telesni nastavci, glava i pronotum, i fizogastrija. Radi razumevanja evolucione istorije<br />grupe, troglomorfne adaptacije su studirane u filogenetskom kontekstu. U analizi<br />evolutivne radijacije roda <em>Anthroherpon</em> kori&scaron;ćena je datirana molekularna filogenija<br />kao okvir za razumevanje diverzifikacije roda, evolucije troglomorfnih karaktera i<br />rekonstrukciju predačkog areala. U svetlu novih nalaza predložena je nova<br />taksonomska organizacija grupe.</p>
7

Estado de conservação e dados de distribuição da fauna troglóbia brasileira com propostas de áreas prioritárias para proteção

Gallão, Jonas Eduardo 08 May 2012 (has links)
Made available in DSpace on 2016-06-02T19:32:04Z (GMT). No. of bitstreams: 1 4572.pdf: 2152921 bytes, checksum: e21c8f519e2e26f72a2fd87da4e3a8f3 (MD5) Previous issue date: 2012-05-08 / Financiadora de Estudos e Projetos / In this paper, we analyzed the Brazilian subterranean fauna, in relation to the actual conservation status, considering the knowledge of its biodiversity, threats to the conservation of this environment and the current legislation relevant to our speleological heritage. The work was divided into chapters, for publication purposes. In chapter I, we present faunal lists of Brazilian troglobitic species (with formal descriptions and not yet described, totaling a minimum of 252 species), their distributions, besides the main causes of destruction / threat of subterranean realm. Still, we propose the Serra do Ramalho, southwestern Bahia state, as a priority area for conservation, since the pressure mining and other factors could decimate the caves of this region biologically important. In chapter II, we discuss about the difficulties of species inclusion in the Red List, and its effective protection, with a case study of Brazilian troglobitic fishes. Problems such as the taxonomic impediment, geographical variations and inclusion only of binomials (Genus species) are discussed. In chapter III, we elected a new hotspot for neotropical subterranean fauna, quartzitic caves from Igatu, in the center region of Chapada Diamantina, central Bahia state. In addition, we tested one of the items of the Instrução Normativa No. 2 of Decreto 6640, which legislates about environmental impact studies of Brazilian caves and we demonstrate that there is not any protectionist law for our subterranean environment. / No presente trabalho, analisamos a fauna subterrânea brasileira, em relação ao seu status de conservação atual, contemplando o conhecimento de sua biodiversidade, as ameaças à conservação deste ambiente e a atual legislação pertinente ao nosso patrimônio espeleológico. O trabalho foi dividido em capítulos, para fins de publicação. No capítulo I apresentamos listas faunísticas de troglóbios brasileiros (com descrições formais e os ainda não descritos, totalizando um mínimo de 252 espécies), suas distribuições, além das principais causas de destruição/ameaça do meio subterrâneo. Ainda, propomos a região da Serra do Ramalho, sudoeste da Bahia, como uma área prioritária para conservação, visto que a pressão minerária e outros fatores podem dizimar as cavernas dessa região, biologicamente importantes. Para o capítulo II, versamos sobre as dificuldades de inserção de espécies às Listas de Fauna Ameaçada de Extinção e efetiva proteção destas, com um estudo de caso de peixes troglóbios brasileiros. Problemas como o impedimento taxonômico, variações geográficas e a inserção somente de binômios (Gênero espécie) são abordados. No capítulo III, elegemos um novo hotspot de fauna subterrânea neotropical, as cavernas quatzíticas de Igatu, no centro da Chapada Diamantina, Bahia central. Além disso, testamos um dos itens da Instrução Normativa nº 2 do Decreto 6.640, o qual legisla sobre as cavernas brasileiras em estudos de impactos ambientais e mostramos que nenhuma lei ambiental para o meio hipógeo é protecionista.
8

Diversidade de invertebrados em cavernas calc?rias do oeste potiguar : subs?dios para a determina??o de ?reas priorit?rias para conserva??o. / Invertebrate diversity in limestone caves in the Oeste Potiguar (Brazil, RN): subsidies for the determination of priority areas for conservation

Bento, Diego de Medeiros 25 March 2011 (has links)
Made available in DSpace on 2014-12-17T14:10:23Z (GMT). No. of bitstreams: 1 DiegoMB_DISSERT_capa_ate_pag68.pdf: 4934333 bytes, checksum: f6bbf7a59936a1c62765b29338c9cb20 (MD5) Previous issue date: 2011-03-25 / It is estimated that the Brazilian karst areas sum about 200.000 km2. The caves, one of the main components of karst, are important windows into the biological studies on hypogean environments. In Rio Grande do Norte are known 563 caves, and 476 of them are in the municipalities of Bara?na, Felipe Guerra, Governador Dix-Sept Rosado, Apodi and Mossor?, the Western region of the State. However, like in the rest of the country, the cave fauna of the State is still poorly understood. This study used data from invertebrates harvested in 47 caves and aimed to analyze the effect of environmental change between the dry and rainy seasons in the communities of cave invertebrates, characterize these communities and evaluate the relationships between morphological and biotic variables of the caves and surroundings, and to define priority areas for conservation of cave environments of the study area from biotic parameters. Strong effects were found in the community structure of cave invertebrates due environmental changes between seasons, with values of total richness, abundance, diversity and ecological complexity significantly higher in the rainy season. It was possible to assess how the morphology of the cave and the external environment variables affect the biotic system, so that the variety of resources, forest cover in the vicinity, the area of the cave and its entrance were the variables that best explained the structure communities of cave invertebrates in the region. High values of total richness of invertebrates (36,62 ? 14,04 spp / cave) and troglomorphic species (61 species, mean 1,77 ? 2,34 spp / cave) were found and, given the biological relevance in the context of the area national and the imminent anthropogenic pressures existing, we defined four priority areas for actions aiming cave biodiversity conservation in the region. / Estima-se que as ?reas c?rsticas brasileiras perfa?am cerca de 200 mil km2. As cavernas, um dos principais componentes do relevo c?rstico, s?o uma importante janela para a realiza??o de estudos biol?gicos sobre os ambientes hip?geos. No Rio Grande do Norte s?o conhecidas 563 cavidades, sendo que 476 delas encontram-se nos munic?pios de Bara?na, Felipe Guerra, Governador Dix-Sept Rosado, Apodi e Mossor?, regi?o Oeste do Estado. No entanto, a exemplo do restante do pa?s, a fauna cavern?cola do RN ainda ? pobremente conhecida. O presente estudo utilizou dados de coletas de invertebrados realizadas em 47 cavernas e teve como objetivos analisar o efeito das altera??es ambientais entre as esta??es seca e chuvosa nas comunidades de invertebrados cavern?colas, caracterizar essas comunidades e avaliar as rela??es entre vari?veis bi?ticas e morfol?gicas das cavernas e do entorno, bem como definir ?reas priorit?rias para a conserva??o de ambientes cavern?colas da ?rea de estudo a partir de par?metros bi?ticos. Foram encontrados fortes efeitos sobre a estrutura das comunidades de invertebrados cavern?colas em fun??o das mudan?as ambientais entre as esta??es, com valores de riqueza total, abund?ncia, diversidade e complexidade ecol?gica significativamente maiores na esta??o chuvosa. Foi poss?vel avaliar como a morfologia da caverna e vari?veis do ambiente externo influenciam as vari?veis bi?ticas do sistema, de forma que a variedade de recursos, a cobertura florestal no entorno, a ?rea da caverna e de suas entradas foram as vari?veis que melhor explicaram a estrutura das comunidades de invertebrados cavern?colas da regi?o. Foram encontrados elevados valores de riqueza total de invertebrados (36,62 ? 14,04 spp/caverna) e de esp?cies trogl?bias (61 esp?cies, m?dia de 1,77 ? 2,34 spp/caverna) e, diante da relev?ncia biol?gica da ?rea no contexto nacional e das iminentes press?es antr?picas existentes, foram definidas quatro ?reas priorit?rias para a??es de conserva??o da biodiversidade cavern?cola regional.

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