No description available.

Natural tropical deciduous forest (TDF) is considered with a medium to small height (< 15 m). Particularly, in Mexico TDF shows a remnant of 36.2% of primary forest driving changes in the structure and species composition. This vegetation in Mexico is mainly transformed into grassland for cattle raising, and agriculture, primarily for self-consumption. More information about the ecology and the social pressures on this vegetation can be seen in Chapter I. The general methods, including sampling allocation and collection, characteristics of the study site, as well the procedure of the research proposal is presented in Chapter II. The main aim of this thesis is to improve the accuracy of predictions of net carbon emissions and the spatial distribution of AGB in the Tropical Deciduous Forest of Mexico. To address this aim, it is important to take into consideration the forest structure, spatial patterns and processes in a natural forest in a multi-scale analysis; also, it is necessary to characterize the spatial socio-economic drivers that influence current AGB losses. With the understanding of such elements, it is possible to reconstruct the potential carbon stocks and estimate the allocation of net carbon emissions due to deforestation and forest degradation. This study shows that it is possible to count net carbon emissions caused by deforestation and forest degradation at a landscape scale. To come to such estimates, it was necessary to reduce the different sources of uncertainty. Chapter III explores different elements that drive the AGB allocation in a mature forest. The AGB in the mature forest was considered as the potential AGB that the forest could get assuming that it has reached its steady state. Different field sampling strategies and allometric equations were evaluated to account for uncertainty in the AGB estimations. The results showed that small sampling design (300-400 m2) and large-sized plots (4 ha) produce the same tree distribution for trees: ≥30 cm in DBH as well as in AGB. These results contradict what has been reported for others (Chave et al., 2004 and 2005) when they refer to the general definition of tropical forest. However, those other studies referred to forests with a much higher precipitation and which can be classified as tropical rain (perennial) forest (Chave et al., 2004). In the tropical deciduous forest, the kind considered in this study, AGB tends to be allocated in small-sized trees. Diverse biophysical characteristics that may drive AGB allocation were considered over different spatial scales. Water stress was the main driver for AGB density at different spatial scales. Nutrients showed little significance to explain AGB as other studies have suggested in secondary forests and/or chronosequences. With this understanding, Chapter IV shows the use of different multi-variable models. Parsimonious models were the result of the variables selection and sensitivity test. Most of the methodologies showed a better performance to explain AGB allocation than a null-model. However, when they were contrasted with independent observations over different spatial resolutions, it was possible to conclude that only GLM was capable of reproducing the spatial patterns, and its estimations were close to observations. Nevertheless, some observations with very large AGB densities were underestimated by the model. This underestimation was related to the presence of few very large-sized trees. These two chapters depict the possibility of accounting for the potential AGB, and the uncertainty, namely whether the landscape could reach it with the absence of human disturbance. Once the potential AGB map was built and validated, it was transformed to carbon stock, using a local carbon concentration estimate. This potential carbon stock map was contrasted to the different available maps of current carbon stocks. Consequently, it was possible to estimate net carbon emissions due to deforestation and forest degradation (Chapter V), suggesting that the general models tend to agree in the total carbon loss. However, there are some spatial discrepancies in the magnitudes of change. Main differences between maps can be reduced by diverse socio-ecological constraints that dominate the landscape. This is important because it may be possible to make future adjustments that would reduce variability, enabling more accurate AGB estimations. However, to individually account for deforestation and forest degradation, more detailed sources of local information are necessary, such as socio-economic variables. Therefore models with a bottom-up perspective would lead to a better understanding and representation of the landscape. Finally, the growing rural population will have larger demands for wood and food, so while remote or protected areas may have the potential for storing high AGB, forest close to settlements and access routes are likely to continue being disturbed, unless affordable alternatives are available for the sustainable use of the forest. In conclusion, the estimation of spatial heterogeneity of AGB in the landscape is of great importance when measuring carbon stocks and ecological dynamics. Various elements influence the AGB allocation in the mature forest. Among all of them, water availability played the most decisive part of various spatial scales. My models support the hypothesis that water availability plays the major role in explaining AGB in Mexico on a local, sub-regional and landscape scale. Model selection produced contrasting AGB estimates and patterns. Moreover, the results of this study tell us that there is not a clear consensus among various current AGB maps. However, they also show that with a multi-model comparison it is possible to identify carbon emissions drivers and calculate total carbon emissions due to forest disturbances. Socio-economic variables played the major role in explaining AGB losses. Therefore, future studies should look into a bottom-up approach for a better understanding and representation of current AGB.

No description available.

Entre as principais oleaginosas eleitas para a produção de biodiesel, encontra-se a mamona (Ricinus communis L.), por possuir elevado teor de óleo, conhecido como óleo de rícino, extraído pela prensagem das sementes, contendo 90% de ácido graxo ricinoléico, o qual confere ao óleo suas características singulares, possibilitando ampla gama de utilização industrial. A produção brasileira de mamona concentra-se na caatinga baiana. A agricultura desta região, embora seja feita sem o uso de insumos agrícolas mantém uma produtividade regular. Com isso, tornou-se importante avaliar o efeito ambiental desta cultura sobre os estoques de C (carbono) e N (nitrogênio) no solo e os mecanismos de sua manutenção. Este trabalho foi realizado em solos de uma fazenda na região de Irecê-BA, tendo como objetivos calcular os estoques de C e N no solo; calcular o fluxo de gases do efeito estufa dos resíduos de mamona; calcular os valores C e N da biomassa microbiana no solo (BMS) e analisar o perfil da comunidade de bactérias fixadoras de N2 no solo por PCR-DGGE. Os resultados indicaram a ausência de variações nos estoques de C entre os tratamentos de mamona com 10, 20 e 50 anos de cultivo (48 Mg ha-1) sendo superados pelos valores encontrados na caatinga (90 Mg ha-1); mesma condição para o estoque de N (5,3 Mg ha-1 nos tratamentos de mamona e 8 Mg ha-1 na caatinga). Já os valores de C-microbiano foram superiores na caatinga, mas não apresentaram diferenças entre os cultivos de mamona; para o N-microbiano, os valores não sofreram diferenças entre as camadas, porém foram inferiores no tratamento de mamona com 10 e 50 anos de cultivo. O fluxo de gases de N-N2O e C-CO2 foram maiores para o tratamento com aplicação de resíduos orgânicos de mamona chegando a 160 mg m-2 h-1 de C-CO2 e 600 mg m-2 h-1 de N-N2O. O teste de redução de acetileno (ARA) e a análise de DGGE indicaram que o perfil da comunidade de bactérias diazotróficas do solo nos diferentes tratamentos sofreu alteração e permitiu a estocagem de N no solo durante os 50 anos de cultivo viabilizando, ambientalmente, a produção de mamona nesta região. / Among the main oils elected for biodiesel production is the castor bean (Ricinus communis L.) for its high oil content, known as castor oil extracted by pressing the seeds containing 90% ricinoleic acid, which gives the oil its unique features, allowing a wide range of industrial use. Brazilian production of castor oil is concentrated in the tropical dry forest of Bahia. Farming in this region, although it is made without the use of agricultural inputs remains a regular productivity. With this, it became important to assess the \"environmental effect\" of this culture on the stocks of C (carbon) and N (nitrogen) in soil and the mechanisms for its maintenance. This work was carried out in soils of a farm in Irecê-BA, aimed to calculate the stocks of C and N in soil, calculated the flows of greenhouse gases from oil waste; to figure out the values of carbon (C) and nitrogen (N) of microbial biomass in soil (BMS and to analyze the profile of the community of N2-fixing bacteria in soil through denaturing gradient gel electrophoresis (DGGE). Results indicated the absence of changes in C stocks between treatments of castor oil with 10, 20 and 50 years of cultivation (about 48 Mg ha-1) being outweighed by values found in the tropical dry forest (90 Mg ha-1); same condition verified for the stock of N (5.3 Mg ha-1 treatments of castor and 8 Mg ha-1 in tropical dry forest). As for values of microbial-C, they were higher in the tropical dry forest and did not present differences between the cultures of castor oil; regarding microbial-N values, there have not been differences between the layers, but they were lower for castor oil with 10 and 50 years of cultivation. The gases flow accumulated N-N2O was significantly higher than that of CCO2 and higher for the treatment of soil with organic fertilizer castor reaching 160 mg m- 2 h-1 of C-CO2 and 600 mg m-2 h-1 of N-N2O. ARA analysis and DGGE indicated that the profile of the diazotrophic community of soil in different treatments had change, allowing the storage of N in soil during the 50 years of cultivation enabling, in environmental terms, the production of castor oil in this region.

Dry forests of the Caribbean islands are regarded as highly disturbed ecosystems and have been characterized as having a high density of small diameter stems, a lower basal area at maturity and a lower species-richness than continental Neotropical dry forests. However, the emerging view regards these ecosystems as phenologically complex, where taxonomic and structural composition is variable over time and space, due to local hydraulic regimes induced by high topographic and climactic variability and varying forms and intensities of disturbance. The former view is derived from a few studies, the majority of which have been conducted in Puerto Rico and from one data review of small 0.1 ha plots representing 4 sites in the Antilles and 25 sits in the continental Neotropics. Overall, little is known about the less-disturbed dry forest formations of the Antilles. Given the emerging view and lack of research in less-disturbed Antillean dry forests, a case study of dry forest structure and composition on the island of St. Lucia is used to examine heterogeneity in dry forest floristic and structural composition on the topographically, floristically and climactically complex island of St. Lucia. Amongst twenty-two 15 x 15 m widely distributed plots, only 11/64 species/genera were found in >50\% of plots and clustering was observed amongst uncommon species, supporting evidence of floristic heterogeneity. Significant differences between the total basal area of each plot (Kruskal-Wallis test, p <0.05) were observed; each plot differed significantly with at least 2 other plots, 6 differed significantly with 10 or more plots, providing evidence for structural heterogeneity. Comparisons were also made with prior research to question generalizations about Antillean dry forests. Amongst large diameter stems, species richness and stem density was higher in this study, when compared to more-disturbed Antillean dry forests. The most speciose dry forest genus was Zanthoxylum, while four families were found to be equally speciose namely, Myrtaceae, Fabaceae, Rutaceae and Rubiaceae, highlighting inconsistencies with prior generalizations. Species-richness values reported amongst Neotropical dry forests were highly variable amongst similar regions, let alone the continental Neotropics, relative to the Antillean Archipelago. Stem density and basal area in St. Lucia was similar to ranges reported throughout the Neotropics, further supporting evidence for intra-island structural variability. The intra-region heterogeneity observed in Antillean and Neotropical continental dry forests indicates that results from localized plot-based studies of structure and composition, should not be extrapolated to broad geo-political regions.

Dry forests of the Caribbean islands are regarded as highly disturbed ecosystems and have been characterized as having a high density of small diameter stems, a lower basal area at maturity and a lower species-richness than continental Neotropical dry forests. However, the emerging view regards these ecosystems as phenologically complex, where taxonomic and structural composition is variable over time and space, due to local hydraulic regimes induced by high topographic and climactic variability and varying forms and intensities of disturbance. The former view is derived from a few studies, the majority of which have been conducted in Puerto Rico and from one data review of small 0.1 ha plots representing 4 sites in the Antilles and 25 sits in the continental Neotropics. Overall, little is known about the less-disturbed dry forest formations of the Antilles. Given the emerging view and lack of research in less-disturbed Antillean dry forests, a case study of dry forest structure and composition on the island of St. Lucia is used to examine heterogeneity in dry forest floristic and structural composition on the topographically, floristically and climactically complex island of St. Lucia. Amongst twenty-two 15 x 15 m widely distributed plots, only 11/64 species/genera were found in >50\% of plots and clustering was observed amongst uncommon species, supporting evidence of floristic heterogeneity. Significant differences between the total basal area of each plot (Kruskal-Wallis test, p <0.05) were observed; each plot differed significantly with at least 2 other plots, 6 differed significantly with 10 or more plots, providing evidence for structural heterogeneity. Comparisons were also made with prior research to question generalizations about Antillean dry forests. Amongst large diameter stems, species richness and stem density was higher in this study, when compared to more-disturbed Antillean dry forests. The most speciose dry forest genus was Zanthoxylum, while four families were found to be equally speciose namely, Myrtaceae, Fabaceae, Rutaceae and Rubiaceae, highlighting inconsistencies with prior generalizations. Species-richness values reported amongst Neotropical dry forests were highly variable amongst similar regions, let alone the continental Neotropics, relative to the Antillean Archipelago. Stem density and basal area in St. Lucia was similar to ranges reported throughout the Neotropics, further supporting evidence for intra-island structural variability. The intra-region heterogeneity observed in Antillean and Neotropical continental dry forests indicates that results from localized plot-based studies of structure and composition, should not be extrapolated to broad geo-political regions.

Submitted by (ana.araujo@ufrpe.br) on 2016-08-22T12:23:31Z No. of bitstreams: 1 Edson Silva Barbosa Leal.pdf: 3379053 bytes, checksum: b1fe194b6edd33f847fe31aef1c6cccf (MD5) / Made available in DSpace on 2016-08-22T12:23:32Z (GMT). No. of bitstreams: 1 Edson Silva Barbosa Leal.pdf: 3379053 bytes, checksum: b1fe194b6edd33f847fe31aef1c6cccf (MD5) Previous issue date: 2012-02-29 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / In terrestrial biome Caatinga, although this is the only exclusively Brazilian biome and one of the 37 major natural regions of the world along with the Amazon and the Cerrado (Savannah), as well as presenting only 52,6% of its original vegetation cover due the fast rate of deforestation and desertification that affects the region, the lack of knowledge about the diversity, taxonomy, ecology, geographic distribution and conservation status of the bats undermine conservation and management initiatives (only 2% of the biome is protected by law), as well as regional analysis and the comparison of the diversity and richness among different areas. This study aims (i) identify the components of the community of Chiroptera in three geographical areas of Caatinga in the states of Paraíba and Ceará, (ii) calculate and compare the indexes of Diversity, Richness, Dominance, Similarity and Equitability and (iii) verify the influence of seasonality in the richness, abundance and composition on the species in the studied areas. After a capture effort of 216,2 X 105 h.m² (24,0 105 h.m2 per area) 454 bats were captured (excluding 34 recaptures), belonging to 19 species, 16 genera and five families: Phyllostomidae (12 species/418 captures), Noctilionidae (2/5), Vespertilionidae (3/24), Emballonuridae (1/6) e Molossidae (1/1). Distributed in seven trophic guilds, with a higher representation of frugivorouss, insectivorous and nectarivorous. 142 specimens of 11 species were captured, with two exclusives, Peropteryx macrotis and Noctilio albiventris, In Pé Branco Farm, Coremas, PB (Area I) four families were registred; In Galante Ranch, São José de Piranhas, PB (Area II), 137 specimens of 11 families where captured, two exclusives (Micronycteris megalotis and Molossus molossus) and 175 specimens of 13 species, with five exclusives (Artibeus lituratus, Sturnira lilium, Phyllostomus discolor, Eptesicus sp. and Lasiurus blossevillii), belonging to two families in Cajuí Ranch, Milagres, CE (Area III). Among the 19 species that were collected, there is a highlight to the first record of Noctilio albiventris to the state of Paraíba. The present record expands to 57 the number of bat species listed for the Paraíba and to 39 that registered in this Caatinga. It emphasizes that the increment of surveys directed to noctilionids in this state, may probably result not only in new records, but also in obtaining data to help to infer about its conservation status this species considered a bio-indicator of water quality and water pollution. its distribution and, abundance, may be strongly related to physical and chemical qualities of the habitat. The most abundant species in these inventories were Artibeus planirostris (n=241; 53,08%), followed by Carolliia perspicillata (n=89; 19,60%), Glossophaga soricina (n=50; 11,01%) and Myotis nigricans (n=22; 4,84%), that, together, represent 84,55% of all the specimens captured. With a low diversity, except when compared with all the sampling region, due the dominance of A. planirostris, C. perspicillata and G. soricina, the richness observed in each area is inside the expected to the Caatinga, despite the fact that the richness estimators mean used, based on the abundance and the incidence, indicates a poor sampling effort against the capture effort used in the areas I (PB) (Ec=2000 h.net; Sobs=11; Chao 1= 12 (Min.), Jacknife 2= 17,68 (Max.), Med.= 13,74; H’=0,79; 1-D=0,60; Eq=0,33 Dbp=0,59; Ds=0,40), II (PB) (Ec=2000 h.net; Sobs= 11; Bootstrap= 12,81 (Min.), Chao 2= 20,44 (Max.), Med.= 15,64; H’=0,78; 1-D=0,62; Eq=0,33; Dbp=0,58; Ds=0,38) and III (CE) (Ec=2000 h.net; Sobs= 13; Bootstrap= 15,22 (Min.), Chao 2= 20,35 (Max.), Med.= 21,14; H’=0,99; 1-D=0,73; Eq=0,39 Dbp=0,44; Ds=0,27) and in total sampling (Ec=6000 h.net; Sobs=19; Bootstrap= 22,16 (Min.), Chao 2= 32,75 (Max.), Med= 26,39; H’=1,57; 1-D=0,67; Eq=0,53 Dbp=0,18; Ds=0,11). The t test (student) shows that there is no significant difference between the Shannon diversity indexes to the pairs: Areas I (PB) and II (PB) (Tcalc=0,062; gl=278,52; p>0,05), Areas I (PB) and III (CE) (Tcalc=1,29; gl=309,19; p>0,05) and, Areas II (PB) and III (CE) (Tcalc=1,34; gl=299,94; p>0,05). As for the similarity, the closest are I and II (PB) (J=0, 57; Cn=0, 86) and the less similar are II (PB) and III (CE) (J=0, 41; Cn=0, 78), with a mean of the general similarity level of 46% (Jaccard) and 80% (Sonresen). In the total sampling, there was a variation in abundance and richness among the dry season (152 specimens, 17 species), which represented 33, 48% and 89, 47$ of the total of captures and species registered, respectively, and rainy (302 or 66, 52%; 13 or 68, 42%), with a significant difference in abundance (x2 = 51.345, gl = 18, p = 0). Eleven species occurred in both seasons and eight were exclusives, two in the rainy season, L. blossevillii (n=1) and M. molossus (n=1) and six in the dry season, P. macrotis (n=6), N. albiventris (n=2), M. megalotis (n=1), P. discolor (n=1), S. lilium (n=1) and Eptesicus sp. (n=1). The amount of captures per species varied between the dry and rainy season, with a significant difference for A. planirostris (181/rainy and 60/dry), the most abundant species, and C. perspicillata (62/rainy and 27/dry), more abundant in the rainy season. There was no significant difference in the species abundance between the two seasons in areas II (PB) (X2 = 17.102, gl = 10, p = 0.0721) and III (CE) (X2 = 3.743, gl = 12, p = 0.9876), only in area I (PB) (X2 = 53.365, gl = 10, p = 0). And, in general, there was no significant difference in the specific richness between the dry and rainy seasons among the three geographical areas studied (X2 =0,554; gl =2; p =0, 75). / No bioma Caatinga, apesar deste ser o único exclusivamente brasileiro e uma das 37 grandes regiões naturais do mundo ao lado da Amazônia e do Cerrado, bem como apresentar apenas 52,6% de sua cobertura vegetal original devido ao acelerado ritmo de descaracterização e desertificação que acomete a região, a deficiência no conhecimento da diversidade, taxonomia, ecologia, distribuição geográfica e status de conservação de morcegos prejudicam iniciativas conservacionistas (apenas 2% do bioma é protegido por lei) e de manejo, bem como análises regionais e a comparação da diversidade e riqueza específica entre diversas áreas. O presente trabalho teve como objetivos (i) identificar os componentes da comunidade de Chiroptera em três áreas geográficas de Caatinga nos estados da Paraíba e Ceará, (ii) calcular e comparar os Índices de Diversidade, Riqueza, Dominância, Similaridade e Equitabilidade e, (iii) verificar a influência da sazonalidade na riqueza, abundância e composição de espécies nos ambientes estudados. Após um esforço de captura de 216,2 x 105 h.m2 (24,0 105 h.m2 por área) foram capturados 454 morcegos (excluindo 34 recapturas), pertencentes a 19 espécies, 16 gêneros e cinco famílias: Phyllostomidae (12 espécies/418 capturas), Noctilionidae (2/5), Vespertilionidae (3/24), Emballonuridae (1/6) e Molossidae (1/1). Distribuídos em sete guildas tróficas, com maior representação de frugívoros, insetívoros e nectarívoros. Foram obtidos 142 indivíduos de 11 espécies, com duas exclusivas, Peropteryx macrotis e Noctilio albiventris, Na Fazenda Pé Branco, Coremas, PB (Área I) foram registradas quatro famílias; Para o Sítio Galante, São José de Piranhas, PB (Área II), foram listadas 137 indivíduos de 11 espécies, duas exclusivas (Micronycteris megalotis e Molossus molossus e 175 indivíduos de 13 espécies, com cinco exclusivas (Artibeus lituratus, Sturnira lilium, Phyllostomus discolor, Eptesicus sp. e Lasiurus blossevillii) distribuídos entre duas famílias no Sítio Cajuí, Milagres, CE (Área III). Das 19 espécies coletadas no geral, destaca-se o primeiro registro de Noctilio albiventris para o estado da Paraíba. O presente registro expande para 57 o número de espécies listadas para a Paraíba e para 39 aquele registrado na Caatinga desta. E, enfatiza que o incremento de levantamentos direcionados aos noctilionídeos nesse estado, deve resultar não apenas em novos registros, mas também na obtenção de dados que ajudem a inferir sobre o status de conservação dessa espécie considerada uma bio-indicadora de qualidade de água e poluição aquática. Cuja distribuição, e abundância, pode estar fortemente relacionada a qualidade física e química do habitat. A espécie mais abundante nesses inventários foi Artibeus planirostris (n=241; 53,08%), seguida por Carolliia perspicillata (n=89; 19,60%), Glossophaga soricina (n=50; 11,01%) e Myotis nigricans (n=22; 4,84%), que juntas representam 84,55% de todos os indivíduos capturados. Com uma diversidade baixa, salvo quando considerado toda a região amostral, devido à dominância de A. planirostris, C. perspicillata e G. soricina, a riqueza observada em cada área está dentro do esperado para a Caatinga, apesar de a média dos estimadores de riqueza, baseados na abundância e incidência, utilizados indicar um esforço amostral insatisfatório diante do esforço de captura empregado nas áreas I (PB) (Ec=2000 h.rede; Sobs=11; Chao 1= 12 (Mín.), Jacknife 2= 17,68 (Máx.), Méd.= 13,74; H’=0,79; 1-D=0,60; Eq=0,33 Dbp=0,59; Ds=0,40), II (PB) (Ec=2000 h.rede; Sobs= 11; Bootstrap= 12,81 (Mín.), Chao 2= 20,44 (Máx.), Méd.= 15,64; H’=0,78; 1-D=0,62; Eq=0,33; Dbp=0,58; Ds=0,38) e III (CE) (Ec=2000 h.rede; Sobs= 13; Bootstrap= 15,22 (Mín.), Chao 2= 20,35 (Máx.), Méd.= 21,14; H’=0,99; 1-D=0,73; Eq=0,39 Dbp=0,44; Ds=0,27) e na amostragem total (Ec=6000 h.rede; Sobs=19; Bootstrap= 22,16 (Mín.), Chao 2= 32,75 (Máx.), Média= 26,39; H’=1,57; 1-D=0,67; Eq=0,53 Dbp=0,18; Ds=0,11). O Teste t (student) demonsstrou que não há diferenças significativas entre os índices de diversidade de Shannon para os pares: Áreas I (PB) e II (PB) (Tcalc=0,062; gl=278,52; p>0,05), Áreas I (PB) e III (CE) (Tcalc=1,29; gl=309,19; p>0,05) e, Áreas II (PB) e III (CE) (Tcalc=1,34; gl=299,94; p>0,05). Quanto à similaridade, as mais próximas são I e II (PB) (J=0,57; Cn=0,86) e as menos similares são II (PB) e III (CE) (J=0,41; Cn=0,78), sendo a média da taxa de similaridade geral de 46% (Jaccard) e 80% (Sonresen). Na amostragem geral ocorreu uma variação na abundância e riqueza entre a estação seca (152 capturas; 17 espécies), a qual representou 33,48% e 89,47% do total de capturas e espécies registradas no presente estudo, respectivamente, e chuvosa (302 ou 66,52%; 13 ou 68,42%), com diferença significativa na abundância (x2 = 51.345, gl = 18, p = 0). Onze espécies ocorreram nas duas estações e oito foram exclusivas, duas no período chuvoso L. blossevillii (n=1) e M. molossus (n=1) e seis no seco P. macrotis (n=6), N. albiventris (n=2), M. megalotis (n=1), P. discolor (n=1), S. lilium (n=1) e Eptesicus sp. (n=1). O número de capturas por espécie variou entre as estações seca e chuvosa, com diferença significativa para A. planirostris (181/chuvosa e 60/seca), a espécie mais abundante, e C. perspicillata (62/chuvosa e 27/seca), mais capturadas no período chuvoso. Não houve diferenças significativas na abundância das espécies entre as duas estações climáticas nas áreas II (PB) (X2 = 17.102, gl = 10, p = 0.0721) e III (CE) (X2 = 3.743, gl = 12, p = 0.9876), apenas para a área I (PB) (X2 = 53.365, gl = 10, p = 0). E, de forma geral, para as três áreas estudadas entre os períodos seco e chuvoso não houve diferenças significativas na riqueza específica (X2 =0,554; gl =2; p =0,75).

Entre as principais oleaginosas eleitas para a produção de biodiesel, encontra-se a mamona (Ricinus communis L.), por possuir elevado teor de óleo, conhecido como óleo de rícino, extraído pela prensagem das sementes, contendo 90% de ácido graxo ricinoléico, o qual confere ao óleo suas características singulares, possibilitando ampla gama de utilização industrial. A produção brasileira de mamona concentra-se na caatinga baiana. A agricultura desta região, embora seja feita sem o uso de insumos agrícolas mantém uma produtividade regular. Com isso, tornou-se importante avaliar o efeito ambiental desta cultura sobre os estoques de C (carbono) e N (nitrogênio) no solo e os mecanismos de sua manutenção. Este trabalho foi realizado em solos de uma fazenda na região de Irecê-BA, tendo como objetivos calcular os estoques de C e N no solo; calcular o fluxo de gases do efeito estufa dos resíduos de mamona; calcular os valores C e N da biomassa microbiana no solo (BMS) e analisar o perfil da comunidade de bactérias fixadoras de N2 no solo por PCR-DGGE. Os resultados indicaram a ausência de variações nos estoques de C entre os tratamentos de mamona com 10, 20 e 50 anos de cultivo (48 Mg ha-1) sendo superados pelos valores encontrados na caatinga (90 Mg ha-1); mesma condição para o estoque de N (5,3 Mg ha-1 nos tratamentos de mamona e 8 Mg ha-1 na caatinga). Já os valores de C-microbiano foram superiores na caatinga, mas não apresentaram diferenças entre os cultivos de mamona; para o N-microbiano, os valores não sofreram diferenças entre as camadas, porém foram inferiores no tratamento de mamona com 10 e 50 anos de cultivo. O fluxo de gases de N-N2O e C-CO2 foram maiores para o tratamento com aplicação de resíduos orgânicos de mamona chegando a 160 mg m-2 h-1 de C-CO2 e 600 mg m-2 h-1 de N-N2O. O teste de redução de acetileno (ARA) e a análise de DGGE indicaram que o perfil da comunidade de bactérias diazotróficas do solo nos diferentes tratamentos sofreu alteração e permitiu a estocagem de N no solo durante os 50 anos de cultivo viabilizando, ambientalmente, a produção de mamona nesta região. / Among the main oils elected for biodiesel production is the castor bean (Ricinus communis L.) for its high oil content, known as castor oil extracted by pressing the seeds containing 90% ricinoleic acid, which gives the oil its unique features, allowing a wide range of industrial use. Brazilian production of castor oil is concentrated in the tropical dry forest of Bahia. Farming in this region, although it is made without the use of agricultural inputs remains a regular productivity. With this, it became important to assess the \"environmental effect\" of this culture on the stocks of C (carbon) and N (nitrogen) in soil and the mechanisms for its maintenance. This work was carried out in soils of a farm in Irecê-BA, aimed to calculate the stocks of C and N in soil, calculated the flows of greenhouse gases from oil waste; to figure out the values of carbon (C) and nitrogen (N) of microbial biomass in soil (BMS and to analyze the profile of the community of N2-fixing bacteria in soil through denaturing gradient gel electrophoresis (DGGE). Results indicated the absence of changes in C stocks between treatments of castor oil with 10, 20 and 50 years of cultivation (about 48 Mg ha-1) being outweighed by values found in the tropical dry forest (90 Mg ha-1); same condition verified for the stock of N (5.3 Mg ha-1 treatments of castor and 8 Mg ha-1 in tropical dry forest). As for values of microbial-C, they were higher in the tropical dry forest and did not present differences between the cultures of castor oil; regarding microbial-N values, there have not been differences between the layers, but they were lower for castor oil with 10 and 50 years of cultivation. The gases flow accumulated N-N2O was significantly higher than that of CCO2 and higher for the treatment of soil with organic fertilizer castor reaching 160 mg m- 2 h-1 of C-CO2 and 600 mg m-2 h-1 of N-N2O. ARA analysis and DGGE indicated that the profile of the diazotrophic community of soil in different treatments had change, allowing the storage of N in soil during the 50 years of cultivation enabling, in environmental terms, the production of castor oil in this region.

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Submitted by Lara Oliveira (lara@ufersa.edu.br) on 2018-03-28T19:13:51Z No. of bitstreams: 1 VinícioHSTS_DISSERT.pdf: 1256095 bytes, checksum: 76aa27433e8975c99df2593a8bb94c15 (MD5) / Rejected by Vanessa Christiane (referencia@ufersa.edu.br), reason: Solicitado pela servidora Lara on 2018-03-29T12:32:20Z (GMT) / Submitted by Lara Oliveira (lara@ufersa.edu.br) on 2018-03-29T16:39:04Z No. of bitstreams: 1 VinícioHSTS_DISSERT.pdf: 1256095 bytes, checksum: 76aa27433e8975c99df2593a8bb94c15 (MD5) / Approved for entry into archive by Vanessa Christiane (referencia@ufersa.edu.br) on 2018-06-18T16:49:21Z (GMT) No. of bitstreams: 1 VinícioHSTS_DISSERT.pdf: 1256095 bytes, checksum: 76aa27433e8975c99df2593a8bb94c15 (MD5) / Approved for entry into archive by Vanessa Christiane (referencia@ufersa.edu.br) on 2018-06-18T16:49:57Z (GMT) No. of bitstreams: 1 VinícioHSTS_DISSERT.pdf: 1256095 bytes, checksum: 76aa27433e8975c99df2593a8bb94c15 (MD5) / Made available in DSpace on 2018-06-18T16:50:10Z (GMT). No. of bitstreams: 1 VinícioHSTS_DISSERT.pdf: 1256095 bytes, checksum: 76aa27433e8975c99df2593a8bb94c15 (MD5) Previous issue date: 2017-03-29 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Owing to high environmental temperatures in combination with elevated solar radiation, the Brazilian SeasonallyDry Tropical Forest, the Caatinga, is a thermally challenging environment for bees, particularly during food collection outside of the nest. The aim of the present study was to investigate the adaptations of bees that allow these animals to survive the thermal conditions of this biome. As model species for our study, we used Melipona subnitida, a stingless bee species (Apidae, Meliponini), endemic from Caatinga. We analysed the following features: (1) the critical thermal maximum (CTmax) of the individuals (both young workers and foragers) as well as the best acclimation time for this kind of study (acclimation times tested: without acclimation, 20 min, 12 h, 48 h, 72 h); (2) The influence of ambient temperature in direct sunlight (Ta) on the thoracic temperature of foragers (Ttx); (3) the possible heat transfer from the thorax to the abdomen, assessed through the temperature difference between these two body parts associated with ambient temperature in both alive and dead individuals; and (4) the role of the thoracic hairs in heating and cooling rates of the bees. The results of the experiments demonstrated that (1) there was no significant difference concerning CTmax between young worker bees and foragers. After 48 hours of acclimation (acclimation time showing the highest CTmax and the lowest variation compared to the other acclimation times tested), the bees' average CTmax was 50.2°C ± 0.7. (2) The foragers' Ttx increased with increasing Ta. At Ta < 40°C, the bees' Ttx was higher than Ta; however, at Ta > 41°C, the forgers' Ttx remained below Ta. (3) There is a possible active heat transfer from the thorax (Ttx) to the abdomen (Tabd) given that, as Ta increased, the difference between Ttx and Tabd decreased in alive foragers. In dead individuals, in contrast, we did not observe this association with Ta. The difference between Ttx and Tabd was relatively constant over all studied Tas. (4) The thoracic hair slow down the heating of M. subnitida. Dead bees without thoracic hair had a higher heating rate than dead bees with their natural air cover. However, there was no difference between the two experimental groups concerning the cooling rates. The results of this study demonstrate that M. subnitida tolerates ambient temperatures that are higher than those found in their natural outside environment. In addition, foragers control their body temperature through active (heat transfer to the abdomen) and passive (thoracic hair) mechanisms, which enables the bees to forage at high environmental temperatures. Results like these of the present study provide important insights into the adaptations necessary to deal with increasing environmental temperatures, as predicted by global warming scenarios / Devido às temperaturas ambientais elevadas em combinação com um alto índice de radiação solar, a Floresta Tropical Sazonalmente Seca brasileira, a Caatinga, é um ambiente termicamente desafiador para abelhas, principalmente durante a coleta de alimento fora do ninho. O objetivo do presente estudo foi investigar as adaptações de abelhas para lidar com as condições térmicas da Caatinga. Como modelo de estudo foi utilizada Melipona subnitida, uma espécie de abelha sem ferrão (Apidae, Meliponini) nativa desse bioma. Foi analisado (1) a temperatura crítica máxima (CTmax) dos indivíduos (operárias jovens e forrageadoras) e o tempo de aclimatação adequado para esse tipo de estudo (tempos de aclimatação testados: sem aclimatação, 30 min, 12 h, 48 h, 72 h); (2) o efeito da temperatura ambiente ao sol (Ta) sobre a temperatura torácica (Ttx) das forrageadoras; (3) a possível transferência de calor do tórax para o abdômen, mensurando a diferença de temperaturas entre estas duas áreas, em função da temperatura ambiente, para abelhas vivas e mortas; e (4) o papel da pelagem torácica na taxa de aquecimento e resfriamento das abelhas. Os resultados dos experimentos mostraram que (1) não houve diferença significativa com respeito ao CTmax entre abelhas jovens e forrageadoras. Após 48 horas de aclimatação (tempo de aclimatação com maior CTmax e menor variação comparado aos outros tempos de aclimatação), a CTmax média das abelhas foi de 50,2°C ± 0,7. (2) A Ttx das forrageadoras aumentou conforme aumentou a Ta. Em Ta < 40°C, a Ttx se manteve acima da Ta; já em Ta > 41°C, a Ttx ficava abaixo da Ta. (3) Acontece uma possível transferência ativa de calor do tórax (Ttx) para o abdômen (Tabd), pois a medida que a Ta aumentou, a diferença da Ttx e da Tabd em forrageadoras vivas diminuiu. Já em abelhas mortas não foi observada essa relação com a Ta. A diferença ente Ttx e Tabd foi praticamente constante em todas as Ta estudadas. (4) A pelagem retarda o aquecimento de M. subnitida. Abelhas mortas sem pelagem mostraram uma taxa de aquecimento maior do que as abelhas mortas com a pelagem natural. Porém, não houve diferença entre esses dois grupos experimentais com respeito às taxas de resfriamento. Os resultados desse estudo mostram que M. subnitida consegue tolerar temperaturas superiores às encontradas naturalmente no ambiente externo. Adicionalmente, as forrageadoras controlam a temperatura corporal através de mecanismos ativos (transferência de calor para o abdômen) e passivos (pelagem torácica), o que permite que esta espécie consiga forragear em temperaturas elevadas. Resultados como estes dão subsídios para entender melhor as adaptações necessárias para lidar com um aumento da temperatura ambiental, como previsto por cenários de aquecimento global, o que vai ser importante para possíveis ações voltadas para a conservação desta espécie / 2018-03-28