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Biodiversity and sustainability in the Bulungan Research Forest, East Kalimantan, Indonesia : the response of plant species to loggingSamsoedin, Ismayadi January 2007 (has links)
This study reports forest structure, regeneration and the soil properties from unlogged and logged forest in the Bulungan Research Forest, Malinau District, East Kalimantan, Indonesia. Four sites were compared by using four 1-ha replicate plots in each of primary forest (PF), 5, 10 and 30-yr old logged forest (LF-5, LF-10, LF- 30). The tree species composition differ among forest types, as it was shown that the mean value of similarity indices for all pairs were 0.215 (for the Jaccard index) and 0.353 (for the Sorensen index). The low values for similarities among forest types were most probably caused by low numbers of species shared between each forest type. Both correlation values, r = 0.023 for Jaccard index and r = 0.031 for Sorensen index, showed no strong correlation between the similarity index (C) and the distance between forest types. This supports the use of a chronosequence approach. A total of 914 tree species with ³ 10 cm dbh were recorded from 223 genera and 65 families. There were no significant differences in mean species numbers (166 – 180/ha) among treatments. Mean density of species was lower in LF-5 and LF-10 (501/ha) than in PF or LF-30 (605/ha and 577/ha); similarly to mean basal area (LF-5, 28.5 m2/ha; LF-10, 32.6 m2/ha) vs. PF (45.8 m2/ha) and LF-30 (46.9 m2/ha). Dead wood on the forest floor was significantly higher in LF-10 (75 m3/ha) than in the other treatments. Seedlings (< 2 cm dbh) of 1,022 species were recorded from 408 genera and 111 families. The mean number of tree seedling species ranged between 170-206; the mean density of seedlings was about two-fold lower in LF-10 (2790/ha) than in the other treatments. Saplings (>2 – 9.9 cm dbh) of 802 species belonged to 241 genera and 65 families. There was a high variability in species richness across treatments (89 – 191/ha), but not in stem numbers. The Dipterocarpaceae family was dominant in all treatments, followed by the Euphorbiaceae. The soils were acidic, low in nutrients and had low to very low fertility. Both primary and logged forest areas are marginal or not suitable for sustained production of plantation crops. Logging caused soil compaction in LF-30. Although in terms of number of species and trees, amount of BA, number of saplings and seedlings LF-30 appeared to have satisfied prescriptions for a second harvest, ecologically the forest is far from mature. The Indonesian Selective Cutting and Replanting (TPTI) system may need to be revised to a 35 – 45 year cycle to ensure long-term forest productivity in terms of not only timber but other goods and ecosystem services, the value of which are never quantified in monetary terms, but can be higher than the timber revenue.
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Shifting cultivation and fallowing practices in a "land-abundant" ejido : an intra-community study of Nuevo Becal, Campeche, MexicoAbizaid, Christian January 2000 (has links)
No description available.
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Shifting cultivation and fallowing practices in a "land-abundant" ejido : an intra-community study of Nuevo Becal, Campeche, MexicoAbizaid, Christian. January 2000 (has links)
Shifting cultivation is considered to be a key cause of deforestation in the tropics as agriculturalists transform the rain forest into cropland and later allow for its regeneration through fallowing. Forest fallows strongly influence the ecological and economic potential of shifting cultivation, yet, secondary forest management among shifting cultivators remains poorly understood. This study focuses on secondary forest management among peasant households in a land-abundant ejido, near the Calakmul Biosphere Reserve of Mexico. Data were gathered through in-depth household interviews and field visits with 44 households, accounting for more than 450 fields. Striking differences were found in fallowing practices in Nuevo Becal. The holding of secondary forest is related to access to male labour, wealth in land-assets, household age, and the holding of pasture. Fallow length at the plot level is associated with household age, land holding size and the manner in which land is acquired. Fallow periods tend to be longer for cycles begun from primary forest and appear to have become longer over time. This study demonstrates the importance of the microdynamics that influence differential land use decisions among households under apparently similar environmental and macroeconomic conditions.
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Amazopoly a game of survival in a tropical rain forestMorris, Michael William 01 January 1996 (has links)
No description available.
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As áreas tropicais úmidas e as febres hemorrágicas virais: uma abordagem geográfica na área ambiental e na de saúde / The humid tropical areas and the infectious hemorrhagic diseases: a geographical approach of the Earth environmental and the humans\' healthMoraes, Paulo Roberto 17 August 2007 (has links)
Os ambientes terrestres têm sido gradativamente alterados pelo ser humano, mas a partir da Revolução Industrial, o homem começou a atuar de maneira mais intensa sobre o meio, fazendo com que as modificações ambientais tomassem proporções alarmantes, tanto em velocidade quanto em dimensão. As mudanças, como as climáticas, hídricas e biológicas, entre outras, ocorridas durante o século XX foram as maiores já registradas. As alterações ambientais associadas ao quadro demográfico do mundo contemporâneo, às condições socioeconômicas e à revolução técnico-científico-informacional que interligou o mundo, acabaram resultando em um cenário nunca vivenciado pela humanidade e ao mesmo tempo preocupante, tanto para saúde ambiental da Terra como para a humana. Se por um lado essa situação, baseada principalmente no avanço tecnológico, resultou numa verdadeira revolução nas taxas de mortalidade e na esperança de vida, por outro lado criou um ambiente que vem facilitando a emergência e reemergência de doenças, que pode comprometer o próprio futuro. Esse estudo tem por objetivo principal dar subsídios para o acesso a um conhecimento integrado, em escala global, tanto das alterações ambientais das áreas tropicais úmidas e do quadro socioeconômico dos países localizados nessa faixa tropical, quanto do surgimento e/ou expansão de quatro doenças infecciosas de caráter hemorrágico - dengue hemorrágica, febre amarela, marburg e ebola - no período de 1981 a 2005. No campo teórico-metodológico, a Geografia, mediante as suas características científicas de transitar pelos campos das ciências naturais e humanas, devido ao seu objeto de estudo, ofereceu a sustentação científica necessária para a realização, enquanto o avanço tecnológico das comunicações e da informática, associado ao processo de globalização pelo qual o mundo passa, proporcionou uma realidade de trabalho totalmente nova, permitindo a execução operacional do estudo. Foram realizados levantamentos bibliográficos e estudos sobre aquecimento global, mundo tropical, devastação das florestas tropicais úmidas, condições socioeconômicas dos países localizados nesta porção do globo e expansão das doenças citadas nos últimos 25 anos. O conjunto dos dados foi transformado em uma tabela síntese e em material cartográfico que retrata a situação atual desses países, destacando o nível das condições sócio ambientais e o risco saúde em que se encontram. / The terrestrial environments have been gradually altered by human being but from the Industrial Revolution on, this process has been even more intensive, resulting in environmental modifications of fast, huge and alarming proportions. The changes, such as the climatic, hydric and biological ones, among others, that took place in the 20th century, were the largest registered. The environmental alterations, associated to the current demographic panorama, to the socioeconomic conditions and to the technical-scientific-informational revolution - that have linked the whole world - resulted in a scenario never before experienced by humanity and, at the same time, very preoccupying for the Earth environmental health as well as for the humans. If on one hand that situation, based mainly on the technological progress, has resulted in lower mortality rates and higher life expectancy at birth, on the other hand it has also created an environment that made the emergence and re-emergence of diseases much easier to occur, so that future may be at risk. This study intend to bring up subsidies that allow for access to global integrated knowledge, not only about the environmental changes in the countries located in humid tropical areas and their socioeconomic conditions, but also about the influence of these alterations on the appearance and/or expansion of four infectious hemorrhagic diseases - hemorrhagic dengue, yellow fever, marburg and ebola - in the period from 1981 to 2005. In the theoreticalmethodological field, Geography - in face of its scientific characteristics of acting on the fields of both natural and human sciences, due to its object of studying - offered the necessary scientific support for the study accomplishment, while the technological progress in Communications and Computer Sciences, associated to the current world process of globalization, provided a new view of working, which allowed the operational execution of this study. The study was also based on bibliographical researches in world warming, tropical world, deforestation of tropical rain forests, socioeconomic conditions of the countries where the forests are placed and in the expansion of the mentioned diseases over the past 25 years. The set of data were synthesized in a table and in cartographic material that show the socio environmental conditions and the health risk of these countries.
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Diversidade e abundância de hemiepífitos em um gradiente altitudinal na Floresta Atlântica no Sul do BrasilOrihuela, Rodrigo Leonel Lozano January 2010 (has links)
O objetivo principal deste trabalho foi identificar os principais fatores abióticos e bióticos correlacionados com a distribuição da abundância e riqueza de hemiepífitos primários, secundários e lianas rizo-escandentes, sinúsias que carecem de estudos, em um gradiente altitudinal na Floresta Atlântica sul-brasileira. Alocamos 15 unidades amostrais no total (de 400 m2 cada), distribuídas nas porções inferior (200 - 250 m a.n.m.), média (380 - 430 m) e superior (670 - 720 m) de um gradiente altitudinal no nordeste do Rio Grande do Sul. Amostramos em cada parcela a abundância de cada espécie, a porcentagem de árvores colonizadas por cada sinúsia e as seguintes variáveis explanatórias: abertura do dossel, composição do solo e densidade de árvores com DAP ≥ 5 e 20 cm; e para cada cota altitudinal, a temperatura e precipitação média anual. Utilizamos modelos lineares generalizados para analisar a influência das variáveis na abundância das sinúsias. Encontramos que as variáveis climáticas (precipitação e temperatura) foram as principais variáveis explanatórias relacionadas com variação na abundância e riqueza das três sinúsias analisadas. As distintas formas de vida apresentaram diferenças na intensidade da resposta às variáveis. Foi registrado um aumento de quatro vezes na abundância de hemiepífitos secundários e de praticamente duas vezes para lianas rizo-escandentes, entre a porção inferior e a superior do gradiente, correlacionando-se positivamente com o aumento da precipitação e umidade. A riqueza total de espécies apresentou um decréscimo na porção superior do gradiente, que foi correlacionado ao decréscimo da temperatura. Os resultados encontrados corroboram trabalhos anteriores, com outros grupos vegetais e animais, que afirmam que as variáveis climáticas são as preditoras de primeira ordem da distribuição das espécies e reforçam a necessidade de se analisar distintas formas de vida, pois estas tendem a responder de modo distinto aos fatores ambientais. / The main aim of this study was to analyze the major abiotic and biotic factors correlated with distribution, abundance and richness of primary and secondary hemiepiphytes and root-climbing lianas along an altitudinal gradient of the South Brazilian Atlantic Forest. Fifteen 400-m² square sample plots within three altitudinal levels at the slope of Serra Geral in north-eastern Rio Grande do Sul were defined. Abundance of all species, the percentage of host trees colonized by each synusia, and explanatory variables canopy openness, soil composition and tree density with DBH ≥ 5 and ≥ 20 cm were recorded for each sample plot. Mean annual air temperature and rainfall were recorded for each altitudinal level. Climatic variables (precipitation and temperature) were the main explanatory variables related with the variation in abundance and richness in the three synusiae studied. The three life forms showed different intensities in their response to these variables. The abundance of secondary hemiepiphytes increased up to four times from the lower to upper altitudinal levels, while root-climbing lianas increased almost twice in the same direction, following an increase in precipitation and humidity. Total species richness decreased toward the upper level of the gradient correlated with lower temperatures and colder winter months. Our results corroborate previous studies on other taxonomic groups, which indicate that climatic variables are first-order predictors for species distribution and reinforce the importance to study different life forms, because these may respond in distinct ways to environment factors.
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As áreas tropicais úmidas e as febres hemorrágicas virais: uma abordagem geográfica na área ambiental e na de saúde / The humid tropical areas and the infectious hemorrhagic diseases: a geographical approach of the Earth environmental and the humans\' healthPaulo Roberto Moraes 17 August 2007 (has links)
Os ambientes terrestres têm sido gradativamente alterados pelo ser humano, mas a partir da Revolução Industrial, o homem começou a atuar de maneira mais intensa sobre o meio, fazendo com que as modificações ambientais tomassem proporções alarmantes, tanto em velocidade quanto em dimensão. As mudanças, como as climáticas, hídricas e biológicas, entre outras, ocorridas durante o século XX foram as maiores já registradas. As alterações ambientais associadas ao quadro demográfico do mundo contemporâneo, às condições socioeconômicas e à revolução técnico-científico-informacional que interligou o mundo, acabaram resultando em um cenário nunca vivenciado pela humanidade e ao mesmo tempo preocupante, tanto para saúde ambiental da Terra como para a humana. Se por um lado essa situação, baseada principalmente no avanço tecnológico, resultou numa verdadeira revolução nas taxas de mortalidade e na esperança de vida, por outro lado criou um ambiente que vem facilitando a emergência e reemergência de doenças, que pode comprometer o próprio futuro. Esse estudo tem por objetivo principal dar subsídios para o acesso a um conhecimento integrado, em escala global, tanto das alterações ambientais das áreas tropicais úmidas e do quadro socioeconômico dos países localizados nessa faixa tropical, quanto do surgimento e/ou expansão de quatro doenças infecciosas de caráter hemorrágico - dengue hemorrágica, febre amarela, marburg e ebola - no período de 1981 a 2005. No campo teórico-metodológico, a Geografia, mediante as suas características científicas de transitar pelos campos das ciências naturais e humanas, devido ao seu objeto de estudo, ofereceu a sustentação científica necessária para a realização, enquanto o avanço tecnológico das comunicações e da informática, associado ao processo de globalização pelo qual o mundo passa, proporcionou uma realidade de trabalho totalmente nova, permitindo a execução operacional do estudo. Foram realizados levantamentos bibliográficos e estudos sobre aquecimento global, mundo tropical, devastação das florestas tropicais úmidas, condições socioeconômicas dos países localizados nesta porção do globo e expansão das doenças citadas nos últimos 25 anos. O conjunto dos dados foi transformado em uma tabela síntese e em material cartográfico que retrata a situação atual desses países, destacando o nível das condições sócio ambientais e o risco saúde em que se encontram. / The terrestrial environments have been gradually altered by human being but from the Industrial Revolution on, this process has been even more intensive, resulting in environmental modifications of fast, huge and alarming proportions. The changes, such as the climatic, hydric and biological ones, among others, that took place in the 20th century, were the largest registered. The environmental alterations, associated to the current demographic panorama, to the socioeconomic conditions and to the technical-scientific-informational revolution - that have linked the whole world - resulted in a scenario never before experienced by humanity and, at the same time, very preoccupying for the Earth environmental health as well as for the humans. If on one hand that situation, based mainly on the technological progress, has resulted in lower mortality rates and higher life expectancy at birth, on the other hand it has also created an environment that made the emergence and re-emergence of diseases much easier to occur, so that future may be at risk. This study intend to bring up subsidies that allow for access to global integrated knowledge, not only about the environmental changes in the countries located in humid tropical areas and their socioeconomic conditions, but also about the influence of these alterations on the appearance and/or expansion of four infectious hemorrhagic diseases - hemorrhagic dengue, yellow fever, marburg and ebola - in the period from 1981 to 2005. In the theoreticalmethodological field, Geography - in face of its scientific characteristics of acting on the fields of both natural and human sciences, due to its object of studying - offered the necessary scientific support for the study accomplishment, while the technological progress in Communications and Computer Sciences, associated to the current world process of globalization, provided a new view of working, which allowed the operational execution of this study. The study was also based on bibliographical researches in world warming, tropical world, deforestation of tropical rain forests, socioeconomic conditions of the countries where the forests are placed and in the expansion of the mentioned diseases over the past 25 years. The set of data were synthesized in a table and in cartographic material that show the socio environmental conditions and the health risk of these countries.
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Sistem?tica e biogeografia da linhagem Tetramerium (Acanthaceae) na Am?rica do SulC?rtes, Ana Luiza Andrade 22 August 2013 (has links)
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Previous issue date: 2013-08-22 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES / The genera Schaueria, Streblacanthus, Pachystachys and Thyrsacanthus represent 25% of the Tetramerium lineage (Acanthaceae: Justicieae), currently with about 40 species, distributed mainly in wetlands and drylands in South America. They are herbaceous or shrubs, with large or filiform bracts and diverse floral morphology, revealing adaptations to different pollinators. Systematic studies in the group are scarce, and the only phylogenetic study (Daniel et al. 2008) included only 10% of the species, not solving the generic limits within the lineage. The biogeography of Neotropical Tetramerium lineage is quite complex, structured in three biomes: the Amazon Forest, the Atlantic Forest and Seasonally Dry Forest. Still, there are no investigations on its diversification. Using phylogenetic and biogeographic methods based on plastid (trnL-F, trnT-L, trnS-G andrps16) and nuclear (ITS)data, we complemented and assessed the previous phylogenetic hypothesis, time-calibrated the phylogeny and reconstructed the ancestral area of Tetramerium lineage, focusing particularly on the South American genera. The analysis showed three well-defined clades and the need for a new circumscription for the genera:1- Schaueria, (excluding S. azaleiflora, S. hirsuta, S. humuliflora, S. malifolia and S. parviflora) including three new species and Justicia paranaensis; 2- Pachystachys, encompassing three species of Streblacanthus (except Streblacanthus monospermus) Schaueria azaleiflora and two new species; and 3- Thyrsacanthus, comprising also Carlowrightia sulcata, Justicia angustissima and Schaueria humuliflora, and another Mexican clade (Justicia zopilotensis, J. gonzalezii, Mirandea hyssopus and Yeatesia mabryi). The lineage originated in the Old World and dispersed to the Neotropics between the Miocene and Pliocene, reaching North America, Central America and Amazon. Between the late Miocene and early Pleistocene, the dry forests lineage expanded and, concomitantly, the rainforests lineageretracted, supporting the idea of a South American dry vegetation belt during this period. The vicariance between blocks of dry forests in southwestern South America and the Caatinga in northeastern Brazil, however, indicates a fragmentation of this vegetation at least in the Lower Pleistocene, well before the Last Glacial Maxima as proposed by the Pleistocene Arc hypothesis. Based on the phylogenetic results, we present a taxonomic revision of the genusSchaueria?including identification keys, descriptions, illustrations, comments, distribution maps and a study of pollen grains and seeds under scanning electron microscopy ? and propose a new circumscription for the genus Pachystachys. Finally, we present a color guide ofphotos for South American species ofTetramerium lineage. / Os g?neros Schaueria, Streblacanthus, Pachystachys e Thyrsacanthus representam 25%da linhagem Tetramerium (Acanthaceae: Justicieae), contando atualmente com cerca de 40 esp?cies, distribu?das principalmente em zonas ?midas e secas da Am?rica do Sul. S?o plantas herb?ceas ou arbustivas, com br?cteas largas ou filiformes e morfologia floral diversa, revelando adapta??es a diferentes polinizadores. Estudos sistem?ticos no grupo s?o parcos, e o ?nico estudo filogen?tico (Daniel et al. 2008) incluiu apenas 10% das esp?cies, n?o resolvendo os limites gen?ricos na linhagem. A biogeografia da linhagem neotropical de Tetramerium ? bastante complexa, estruturada em tr?s biomas: Floresta Amaz?nica, Floresta Atl?ntica e Floresta Sazonalmente Seca. Ainda assim, n?o existem investiga??es sobre sua diversifica??o. Utilizando m?todos filogen?ticos e biogeogr?ficos baseados em dados moleculares plastidiais (trnL-F, trnT-L, trnS-G, rps16) e nucleares (ITS), n?s complementamos e avaliamos a hip?tese filogen?tica pr?via, datamos e reconstru?mos a ?rea ancestral da linhagem Tetramerium, focando particularmente nos g?neros da Am?rica do Sul. As an?lises mostraram tr?s clados bem definidos e a necessidade de uma nova circunscri??o para os g?neros:1- Schaueria (excluindo S. azaleiflora, S. hirsuta, S. humuliflora, S. malifolia e S. parviflora) incluindo tr?s novas esp?cies e Justicia paranaensis; 2- Pachystachys englobando tr?s esp?cies de Streblacanthus (exceto Streblacanthusmonospermus), Schaueria azaleiflora e duas novas esp?cies; e 3- Thyrsacanthus compreendendo tamb?m Carlowrightia sulcata, Justicia angustissima e Schaueria humuliflora, e mais um clado mexicano (Justicia zopilotensis, J. gonzalezii, Mirandea hyssopus e Yeatesia mabryi). A linhagem originou-se no Velho Mundo e dispersou para o Neotr?pico entre o Mioceno e o Plioceno, alcan?ando Am?rica do Norte, Central e Amaz?nia. Entre o final do Mioceno e o in?cio do Pleistoceno, a linhagem de florestas secas se expandiu e, concomitantemente, as linhagens de florestas ?midas se retra?ram, sustentando a ideia de uma diagonal seca neste per?odo. A vicari?ncia entre os blocos de florestas secas no sudoeste da Am?rica do Sul e da Caatinga no nordeste do Brasil, no entanto, indica uma fragmenta??o dessa forma??o pelo menos no Pleistoceno Inferior, bem antes da ?ltima M?xima Glacial, como proposto pela hip?tese do Arco do Pleistoceno. Com base nos resultados filogen?ticos, n?s apresentamos uma revis?o taxon?mica do g?nero Schaueria ? incluindo chaves de identifica??o, descri??es, ilustra??es, coment?rios, mapas de distribui??o e estudo de microscopia de varredura de gr?os de p?len e de sementes ? e propomos uma recircunscri??o para o g?nero Pachystachys. Finalmente, ? apresentado um guia de fotos coloridas para as esp?cies sul-americanas da linhagem Tetramerium.
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Cultivation of wild palms in the rainforest of Darién, PanamáCansari, Rogelio. January 1999 (has links)
Great importance is currently being given to any type of ecosystem; the tropical forest is one of them and it is our case. Also, in the same way, importance is given to ecosystems inhabitants, which in one or another manner depend of the ecosystems and for many years have demonstrated a harmonious relation with their environment. / In consequence, this thesis in its first chapter describes relevant issues of human communities that have lived for many years in the tropical forest located in the Darien province in the Republic of Panama. These communities are of the Embera and Wounaan indigenous groups. In particular, I present their point of view and the negative experiences that these groups have found with the scientific research which, in fact, has been conducted within their territories and that they have also been the object of for many years. Due to these conditions, the Embera and Wounaan state the wed to establish new policies to initiate a method of mutual understanding with an individuals and organized groups interested in conducting work in their territory. One of the proposals is to acknowledge participation and the right to understand and explain what is planned to be conducted as a research and to return obtained results by means of a well structured document.
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Diversidade e abundância de hemiepífitos em um gradiente altitudinal na Floresta Atlântica no Sul do BrasilOrihuela, Rodrigo Leonel Lozano January 2010 (has links)
O objetivo principal deste trabalho foi identificar os principais fatores abióticos e bióticos correlacionados com a distribuição da abundância e riqueza de hemiepífitos primários, secundários e lianas rizo-escandentes, sinúsias que carecem de estudos, em um gradiente altitudinal na Floresta Atlântica sul-brasileira. Alocamos 15 unidades amostrais no total (de 400 m2 cada), distribuídas nas porções inferior (200 - 250 m a.n.m.), média (380 - 430 m) e superior (670 - 720 m) de um gradiente altitudinal no nordeste do Rio Grande do Sul. Amostramos em cada parcela a abundância de cada espécie, a porcentagem de árvores colonizadas por cada sinúsia e as seguintes variáveis explanatórias: abertura do dossel, composição do solo e densidade de árvores com DAP ≥ 5 e 20 cm; e para cada cota altitudinal, a temperatura e precipitação média anual. Utilizamos modelos lineares generalizados para analisar a influência das variáveis na abundância das sinúsias. Encontramos que as variáveis climáticas (precipitação e temperatura) foram as principais variáveis explanatórias relacionadas com variação na abundância e riqueza das três sinúsias analisadas. As distintas formas de vida apresentaram diferenças na intensidade da resposta às variáveis. Foi registrado um aumento de quatro vezes na abundância de hemiepífitos secundários e de praticamente duas vezes para lianas rizo-escandentes, entre a porção inferior e a superior do gradiente, correlacionando-se positivamente com o aumento da precipitação e umidade. A riqueza total de espécies apresentou um decréscimo na porção superior do gradiente, que foi correlacionado ao decréscimo da temperatura. Os resultados encontrados corroboram trabalhos anteriores, com outros grupos vegetais e animais, que afirmam que as variáveis climáticas são as preditoras de primeira ordem da distribuição das espécies e reforçam a necessidade de se analisar distintas formas de vida, pois estas tendem a responder de modo distinto aos fatores ambientais. / The main aim of this study was to analyze the major abiotic and biotic factors correlated with distribution, abundance and richness of primary and secondary hemiepiphytes and root-climbing lianas along an altitudinal gradient of the South Brazilian Atlantic Forest. Fifteen 400-m² square sample plots within three altitudinal levels at the slope of Serra Geral in north-eastern Rio Grande do Sul were defined. Abundance of all species, the percentage of host trees colonized by each synusia, and explanatory variables canopy openness, soil composition and tree density with DBH ≥ 5 and ≥ 20 cm were recorded for each sample plot. Mean annual air temperature and rainfall were recorded for each altitudinal level. Climatic variables (precipitation and temperature) were the main explanatory variables related with the variation in abundance and richness in the three synusiae studied. The three life forms showed different intensities in their response to these variables. The abundance of secondary hemiepiphytes increased up to four times from the lower to upper altitudinal levels, while root-climbing lianas increased almost twice in the same direction, following an increase in precipitation and humidity. Total species richness decreased toward the upper level of the gradient correlated with lower temperatures and colder winter months. Our results corroborate previous studies on other taxonomic groups, which indicate that climatic variables are first-order predictors for species distribution and reinforce the importance to study different life forms, because these may respond in distinct ways to environment factors.
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