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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.
51

Efeito de borda na estrutura, diversidade e fenologia de floresta tropical estacional submontana

Santos, Ana Paula Lima do Couto 30 September 2014 (has links)
Submitted by Ricardo Cedraz Duque Moliterno (ricardo.moliterno@uefs.br) on 2016-01-20T23:17:07Z No. of bitstreams: 1 Ana Paula Lima do Cout1.pdf: 2447904 bytes, checksum: 7c9755ccd95ffbece7c6941079071845 (MD5) / Made available in DSpace on 2016-01-20T23:17:07Z (GMT). No. of bitstreams: 1 Ana Paula Lima do Cout1.pdf: 2447904 bytes, checksum: 7c9755ccd95ffbece7c6941079071845 (MD5) Previous issue date: 2014-09-30 / Conselho Nacional de Pesquisa e Desenvolvimento Cient?fico e Tecnol?gico - CNPq / Funda??o de Amparo ? Pesquisa do Estado da Bahia - FAPEB / (Effect of edge in structure, diversity and phenology in seasonal tropical forest submontane) Forest fragmentation causes physical and biological changes with habitat loss and insularization of populations, and the edge effect the most obvious consequence of this process. Thus, this study aimed to investigate the effect of linear edge in a fragment of submontane seasonal forest in the Chapada Diamantina, Bahia, Brazil (12?28'31 "S and 41?23'14''W) in order to analyze the structure and composition vegetation, reproductive phenology and the vegetative phenology, classifying the forest as their leaf pattern, and the functional diversity. Were marked 30 plots (10 x 10 m) random and 15 at the forest edge (0 - 100m) and 15 inside (> 150m) in the power line high voltage. For structural studies were marked all individuals with diameter at breast height ?5 cm. The species were classified according to successional category and phytosociological parameters were calculated and diversity indices. The Shannon - Wiener index was compared by t test Hutcheson and the other parameters by ANOVA. From this study the species with the highest importance value and abundance for the other investigations were chosen. In the reproductive phenological study monthly observations were made over 26 months in 481 individuals (282 on the edge (61 species) and 199 inside (50 species) of forest), recording the presence and absence of flowering (and flower button) and fruiting (immature and mature fruit) for all life forms. It is estimated timing, frequency and duration of phenological events and the species were classified as the pollination and dispersal syndromes. Data were analyzed with G test, linear regression and circular statistics. In the study of functional diversity created a matrix of functional traits to the edge and interior including phenological, structural and reproductive aspects. Measurements of leaf traits (thickness, dry dough sheet per unit area, juiciness, density, leaf area ratio and leaf mass fraction), density and wood water saturation were carried out in the dry and wet seasons (September / 2012 and January / 2013) in 20 species. Regressions were made between phenophases and environmental variables (precipitation, temperature, relative humidity, photoperiod and heat stroke), circular statistics and comparisons of leaf traits and wood density between the dry and rainy season through the G test and ANOVA. The species ordination in relation to leaf and wood attributes was evaluated by Principal Component Analysis (PCA). The functional groups were defined by cluster analysis with distance Gower and calculated indexes Functional richness (FRic), Functional divergence (FDiv), Functional evenness (FEve), Functional dispersion (FDis). ANOVA and linear regression were used to evaluate the rates between areas. In vegetative phenological study followed up the budding and leaf fall 350 individual trees in the community (39 species). Increase the impact of straight edge on the floristic composition was checked, the diversity and abundance of species, while less interference was observed in the tree community structure, as phytosociological parameters and ratios between the guilds did not differ significantly between edge and interior fragment. The phenological analysis revealed that flowering and fruiting at the edge and interior were continued for long, low-intensity periods, asynchronous and assazonal being for most phenophases, with a significant difference in the individual to button number. Seasonality in flowering and fruiting were observed for bush and grass land in both areas and epiphytes to the edge. Similar proportions in the number of species for pollination and dispersal syndromes were found on the edge and inside, with a predominance of melittophilous and animal dispersed species. The vegetation was evergreen, with budding and continuous leaf fall, low intensity and low sync. The leaf bud was related to rainfall and sunshine and fall with precipitation and humidity. Significant variation between the dry and wet seasons were observed in the proportion of saturated water in the wood, leaf area ratio and leaf succulence. ACP showed greater variance for wood density (88.7%) and stored water (11.3%), gathering most species with standard perenif?lios phenological and episodic perenif?lios, other attributes showed no relevance to the phenological patterns. The main functional groups formed on the edge and inside were similar, defined based on the way of life, stratum and pollination and dispersal. Of co-occurring species (40 species), 22.5% belong to different functional groups due to different growth patterns. The functional diversity indices showed higher mean values for the edge, except that Fric was higher in the forest. These were not affected by the distance to the edge. Changes were observed inside in relation to species richness and Shannon - Wiener only for Fric. The implementation of linear infrastructure brings similar impacts to those coming from other types of edges in community structure. In other aspects analyzed the changes were subtle for the tree community, but the same was not true for shrubs, herbs and vines. The vegetation can be classified as seasonal submontane rainforest always green, with small annual variation in the physiognomy of the vegetation, and the perenif?lios and perenif?lios types episodic predominant both in number of species and in their abundance. The leaf traits showed no relevance to phenology, not being good descriptors for the seasonal evergreen forest. There is no significant difference in functional diversity, but the highest rate obtained inside for functional wealth reflects the biological loss caused by the installation on the edge of the linear edge. Appearance evidenced by the greater abundance of Eschweilera tetrapetala Mori inside, an endemic species of submontane forests of the region. This study contributes to future conservation work to note the interference the linear edge on the forest ecosystem, as well as to the classification of the Brazilian forests, to verify the occurrence of seasonal evergreen forests in the Caatinga. / (Efeito de borda na estrutura, diversidade e fenologia de floresta tropical estacional submontana) A fragmenta??o florestal causa mudan?as f?sicas e biol?gicas com perda de habitat e insulariza??o das popula??es, sendo oefeito de borda a consequ?ncia mais evidente desse processo.Assim,objetivou-se investigar o efeito da borda linear em um fragmento de floresta estacional submontana na Chapada Diamantina, Bahia,Brasil (12?28?31??S e 41?23?14??W) com o intuito de analisar a estruturae a composi??o da vegeta??o, a fenologia reprodutivae a fenologia vegetativa, classificando a floresta quanto ao seu padr?o foliar, e a diversidade funcional. Foram marcadas 30 parcelas (10 x 10 m) aleat?rias sendo 15 na borda da floresta (0 - 100m) e 15 no seu interior (>150m) em rela??o ? rede el?trica de alta tens?o. Para o estudo estrutural foram marcados todos os indiv?duos com di?metro ? altura do peito ?5 cm. As esp?cies foram classificadas quanto ? categoria sucessional e foram calculados os par?metros fitossociol?gicos e ?ndices de diversidade. O ?ndice de Shannon - Wienerfoi comparado pelo teste t de Hutcheson e os demais par?metros pela ANOVA. A partir desse estudo foram escolhidas as esp?cies com maior valor de import?ncia e abundancia para as demais investiga??es.No estudo fenol?gico reprodutivo foram realizadas observa??es mensais durante 26 meses a 481 indiv?duos (282 na borda (61 esp?cies) e 199 no interior (50 esp?cies) da floresta), registrando-se a presen?a e aus?ncia de flora??o (bot?o e flor) e frutifica??o (frutos imaturo e maturo) para todas as formas de vida. Estimou-se sincronia, frequ?ncia e dura??o dos eventos fenol?gicos e as esp?cies foram classificadas quanto ?s s?ndromes de poliniza??o e dispers?o. Os dados foram analisados com teste G, regress?o linear e estat?stica circular. No estudo da diversidade funcional criou-se uma matriz de tra?os funcionais para a borda e interior incluindo aspectos fenol?gicos, estruturais e reprodutivos.Mensura??es de atributos foliares (espessura, massa seca de folha por unidade de ?rea, sucul?ncia, densidade, raz?o de ?rea foliar e fra??o de massa foliar), densidade e ?gua de satura??o da madeira foram realizadas nas esta??es seca e chuvosa (setembro/2012 e janeiro/2013) em 20 esp?cies. Foram feitas regress?es entre as fenofases e as vari?veis ambientais (precipita??o, temperatura, umidade relativa, fotoper?odo e insola??o), estat?stica circular e compara??es dos atributos foliares e densidade de madeira entre a esta??o seca e chuvosa atrav?s do teste G e ANOVA. A ordena??o das esp?cies em rela??o aos atributos foliares e de madeira foi avaliada pela An?lise do Componente Principal (ACP). Os grupos funcionais foram definidos por Cluster analysis com dist?ncia de Gower e calculados os ?ndices Functional richness (FRic), Functional divergence (FDiv), Functional evenness (FEve), Functional dispersion (FDis). ANOVA e regress?o linear foram usadas para avaliar os ?ndices entre ?reas. No estudo fenol?gico vegetativo acompanhou-se o brotamento e queda foliar de 350 indiv?duos arb?reos na comunidade (39 esp?cies). Foi verificado um maior impacto da borda linear sobre a composi??o flor?stica,a diversidade e abund?ncia das esp?cies, enquanto menor interfer?ncia foi verificada na estrutura da comunidade arb?rea, uma vez que par?metros fitossociol?gicos e propor??es entre as categorias sucessionais n?o diferiram significativamente entre borda e interior do fragmento.As an?lises fenol?gicas revelaram que a flora??o e frutifica??o na borda e interior foram cont?nuas por per?odos longos e com baixa intensidade, sendo assincr?nico e assazonal para a maioria das fenofases, com diferen?a significativa no n?mero de indiv?duo para bot?o.Sazonalidade na flora??o e frutifica??o foi observada para arbusto e erva terrestre em ambas as ?reas e ep?fitas para a borda.Propor??es semelhantes no n?mero de esp?cies por s?ndromes de poliniza??o e dispers?o foram encontradas na borda e no interior, com predomin?ncia de esp?cies melit?filas e zooc?ricas.A vegeta??o foi perenif?lia, com brotamento e queda foliar cont?nuos, baixa intensidade e baixa sincronia. O brotamento foliar relacionou-se com precipita??o e insola??o e a queda com precipita??o e umidade. Varia??o significativa entre as esta??es seca e chuvosa foram observadas na propor??o de ?gua saturada na madeira, raz?o de ?rea foliar e sucul?ncia da folha. ACP revelou maior varian?a para densidade da madeira (88,7%) e ?gua armazenada (11,3%), agrupando a maioria das esp?cies com padr?o fenol?gico perenif?lios e perenif?lios epis?dicos, os demais atributos n?o apresentaram relev?ncia em rela??o aos padr?es fenol?gicos. Os principais grupos funcionais formados na borda e no interior foram semelhantes, definidos com base na forma de vida, estrato e s?ndrome de poliniza??o e dispers?o. Das esp?cies co-ocorrentes (40 esp?cies), 22,5% pertencem a grupos funcionais distintos devido a diferentes padr?es fenol?gicos. Os ?ndices de diversidade funcional apresentaram valores m?dios superiores para a borda, exceto FRic que foi superior no interior da floresta. Estes n?o foram alterados pela dist?ncia com a borda. Altera??es foram observadas no interior em rela??o ? riqueza de esp?cie e ao ?ndice de Shannon - Wiener apenas para FRic.A implementa??o de infraestruturas lineares traz impactos semelhantes ?queles advindos de outros tipos de bordas na estrutura da comunidade. Nos demais aspectos analisados as varia??es foram sutis para a comunidade arb?rea, mas o mesmo n?o ocorreuem rela??o a arbustos, ervas e trepadeiras. A vegeta??o p?de ser classificada como floresta tropical estacional submontana sempre verde, com pequena varia??o anual na fisionomia da vegeta??o, sendo os tipos perenif?lios e perenif?lios epis?dicos predominantes tanto em n?mero de esp?cies quanto na sua abund?ncia. Os atributos foliares n?o apresentaram relev?ncia em rela??o aos padr?es fenol?gicos, n?o sendo bons descritores para a floresta estacional sempre verde. N?o h? diferen?a significativa na diversidade funcional, mas o maior ?ndice obtido no interior para a riqueza funcional reflete a perda biol?gica ocasionada na borda pela instala??o da borda linear.Aspecto evidenciado pela maior abund?ncia deEschweilera tetrapetala Mori no interior, esp?cie end?mica das florestas submontanas da regi?o. O presente estudo p?de contribuir com futuros trabalhos de conserva??o por constatar a interfer?ncia da borda linear no ecossistema florestal, bem como com a classifica??o das florestas brasileiras, ao verificar a ocorr?ncia de florestas estacional sempre verde no Bioma Caatinga.

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