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Bees are a diverse group of insects responsible for pollinating plants in agricultural and ecological landscapes. Wild bees are impacted by anthropogenic activity and associated habitat loss. Although 75% of bee species nest underground, this nesting strategy has been overlooked. In my thesis, I explored the nesting habitat requirements of ground-nesting bees by studying the relation between bees and edaphic factors. First, I reviewed existing literature about ground-nesting bee nesting characteristics (Chapter 2). I found that certain abiotic factors (e.g., soil texture, temperature, moisture, compaction, slope, and soil surface features), as well as biotic factors (e.g., floral resources, conspecifics, predators), could be key in nest-site selection. I also discuss possible explanations for the choice of these nesting characteristics, particularly edaphic factors. Secondly, in Chapter 3, I assessed relationships between specific soil factors (soil texture, compaction, slope and ground cover) and the wild local ground-nesting bee communities on 35 farms around Ottawa throughout 2018 and 2019. I found that higher percentages of sand and bare ground were linked to increased total ground-nesting bee abundance and species richness, whilst slope and diversity (Simpson’s index) were negatively correlated. Furthermore, associations with soil factors were found to be species-specific, especially for associations with sand content, which were either positive, negative, or non-significant. Ground-nesting bee community’s composition was influenced by sand content, slope, soil compaction and bare ground in sampled agroecosystems. Finally, in Chapter 4, I experimentally tested nesting preferences of ground-nesting bee species for soil texture. Based on one season of sampling, there was no association between bee abundance or species richness and soil texture. Together, my research sheds light on the influence of soil characteristics on species-specific nesting-habitat associations for ground-nesting bees. Along with floral resources which have received far more study, nesting habitat is vital for the well-being and persistence of bee populations, and therefore for their conservation.

Submitted by Celso Magalhaes (celsomagalhaes@ufrrj.br) on 2017-06-13T17:13:20Z No. of bitstreams: 1 2015 - H?lio Moulin Curti Junior.pdf: 3505961 bytes, checksum: 54541b50bce17092a8217c28baed4d90 (MD5) / Made available in DSpace on 2017-06-13T17:13:20Z (GMT). No. of bitstreams: 1 2015 - H?lio Moulin Curti Junior.pdf: 3505961 bytes, checksum: 54541b50bce17092a8217c28baed4d90 (MD5) Previous issue date: 2015-03-23 / The vegetation of the restinga, located in the coastal plains of the Brazilian coast, is considered a set of plant communities arranged in mosaic overlap in soil sandy nature. It has a rich and varied flora resulting from the diversity of its geological origin, topography and environmental conditions. In the municipality of Rio de Janeiro there are few areas with restinga vegetation remnants and correspond to 1.6% of the total number of vegetation of the city. The Municipal Natural Park Grumari (PNMG), where was developed this study, is considered one of the smallest fragments of restinga vegetation of the State of Rio de Janeiro. Located in the west area of the city of Rio de Janeiro, is a protected area administered by the Department of Environment of the Municipality of Rio de Janeiro. This protected area comprises restinga vegetation and analogously to the restingas of the State of Rio de Janeiro has suffered high anthropogenic pressure mainly associated with local tourism, removal of species, fire, high traffic and banana plantation expansion. In the face of human pressure history occurred in PNMG area, it was carried out phytosociological study and as well as researched the relationship of the vegetation of an impacted stretch of restinga Mata with soil factors associated with soil fertility. The objective was to know the tree species in this impacted area. Ten rectangular plots with size of 10 m x 20 m were delimited in the study area and the trees with diameter at breast height greater than or equal to 5 cm were part of the sample. Samples of soil at a depth of 5 cm, were collected in order to proceed to carry out the chemical analysis. Species identification was performed by the RBR Herbarium of the Department of Botany, Institute of Biology of UFRRJ. Canonical correspondence analysis was performed (ACC), via software PC-ORD version 5.0, in order to assess whether the soil chemical factors influence the distribution of tree species in the sampling site. A total of 277 individuals were sampled, with 33 species, 25 genera and 16 families. The species Cupania emarginata (Camboat?), Sapindaceae family, with approximately 50% of the sampled individuals was identified as the dominant species. Cupania emarginata, Tapirira guianensis, Byrsonima sericea, Myrsine guianensis, Eugenia punicifolia, Erythroxylum ovalifolium and Erythroxylum passerinum showed the highest importance value. The Fabaceae family, with 7 species, was the richest. The ACC information indicates that the axes 1 and 2 together accounted for only 14.5% of the variation in the data, indicating a low correlation between soil chemical parameters and the distribution of trees at the sampling site. Due to the large number of species with little representation and as well as the knowledge that some of them are with the level of threat vulnerable or endangered, should be increased efforts to protect this restinga vegetation remaining in the city of Rio de Janeiro. / A vegeta??o de restinga, localizada nas plan?cies costeiras do litoral brasileiro, ? considerada um conjunto de comunidades vegetais dispostas em mosaico que est?o sobrepostas em solo de natureza arenosa. Possui uma flora rica e variada resultante da diversidade da sua origem geol?gica, topografia e condi??es ambientais. No munic?pio do Rio de Janeiro h? poucas ?reas com vegeta??o de restinga remanescente e correspondem a 1,6% do total de vegeta??o da cidade. O Parque Natural Municipal de Grumari (PNMG), onde foi desenvolvido este estudo, ? considerado um dos menores fragmentos de restinga do Estado do Rio de Janeiro. Localizado na zona oeste da cidade do Rio de Janeiro, ? uma unidade de conserva??o administrada pela Secretaria de Meio Ambiente da Prefeitura do Rio de Janeiro. Compreende vegeta??o de restinga e de forma an?loga ?s restingas do Estado do Rio de Janeiro tem sofrido alta press?o antr?pica, principalmente, associada ao turismo local, a retirada de esp?cies, a inc?ndios, ao pisoteio e a expans?o da planta??o de banana. Em face do hist?rico de press?o antr?pica ocorrida na ?rea do PNMG, foi realizado um estudo fitossociol?gico e bem como pesquisou-se a rela??o da vegeta??o de um trecho impactado da Mata de Restinga com os fatores ed?ficos associados ? composi??o qu?mica do solo. Objetivou-se conhecer as esp?cies arb?reas presentes neste trecho impactado. Dez parcelas retangulares com dimens?o de 10 m x 20 m foram delimitadas na ?rea de estudo e as ?rvores com di?metro ? altura do peito maior ou igual a 5 cm fizeram parte da amostragem. Amostras de solo, ? profundidade de 5 cm, foram coletadas a fim de proceder an?lise qu?mica. A identifica??o das esp?cies arb?reas foi realizada junto ao Herb?rio RBR do Departamento de Bot?nica, do Instituto de Biologia da UFRRJ. Procedeu-se an?lise de correspond?ncia can?nica (ACC), via Software PC-ORD vers?o 5.0, com o objetivo de avaliar se os fatores qu?micos do solo influenciam a distribui??o das esp?cies arb?reas no local da amostragem. Um total de 277 indiv?duos foram amostrados, perfazendo 33 esp?cies, 25 g?neros e 16 fam?lias. A esp?cie Cupania emarginata (camboat?), fam?lia Sapindaceae, com aproximadamente 50% dos indiv?duos amostrados, foi identificada como a esp?cie dominante. As esp?cies de maior valor de import?ncia foram Cupania emarginata, Tapirira guianensis, Byrsonima sericea, Myrsine guianensis, Eugenia punicifolia, Erythroxylum ovalifolium e Erythroxylum passerinum. A fam?lia Fabaceae, com 7 esp?cies, apresentou a maior riqueza. As informa??es oriundas da ACC demonstraram que os eixos 1 e 2 somados explicam apenas 14,5% da varia??o dos dados, indicando uma baixa correla??o entre os par?metros qu?micos do solo e a distribui??o das ?rvores no local de amostragem. Devem ser aumentados os esfor?os para prote??o deste remanescente de vegeta??o de restinga da cidade do Rio de Janeiro devido ao elevado n?mero de esp?cies com pequena representatividade e bem como que algumas delas est?o situadas em n?vel de amea?a vulner?vel ou em perigo de extin??o

The primary objective of this study was to determine the degree of correlation between internal water potential of Engelmann spruce trees and selected environmental factors. The secondary objective of the study was to determine the effect of summer precipitation, both in meadow and forested sites, on the soil drying cycle. Four study plots (each roughly 154 square meters) under spruce cover and two study plots (100 square meters) in a small meadow were established. At each spruce plot, a thermocouple psychrometer was installed at one meter above the ground on the north side of three selected, mature Engelmann spruce trees. Thermocouple psychrometers were installed at 5, 15, and 30 cm depths in the soil at the meadow plots and at 15, 30, 45, and 90 cm depths at the spruce plots. A tensiometer and two soil temperature thermocouples were installed near the thermocouple psychrometers at each of the plots but at 15, 30, 45, and 90 cm soil depths. Throughfall gages were placed at each plot to obtain an estimate of rainfall which was not intercepted by the canopy but which fell to the forest floor. Gross precipitation was measured by a 20.3 cm diameter recording gage located at the meadow. Global radiation and wind were recorded at the meadow area also. Air temperature and relative humidity were recorded in wooden shelters. One shelter was located at the meadow area and one was located in the vicinity of the four spruce plots. Except for wind, weather parameters were recorded continuously. Wind movement was totalized on a digital counter and recorded on data sheets when needed. Psychrometric, pressure chamber, and soil data were obtained according to two schedules. Diurnal measurements of trunk water potential in six trees and independent variables were made during seven days in the summer months of 1971. Seasonal measurements of trunk water potential in twelve trees and independent variables were done at periodic intervals during the summer averaging every three to four days. Data to evaluate the effect of summer precipitation on the soil drying cycle was obtained periodically the summer of 1970 and concurrently (for the most part) with tree water potential measurements during 1971. Significant findings of this study included the following: as shown by analyses of variation of the data, within-season variations of tree water potential (by psychrometer and pressure chamber measurements) were statistically significant. In other words, fluctuations in water potential with time were large enough that they could not have been due to chance alone. On an hourly basis for seven cycles of diurnal measurements, daily peaks in wind movement corresponded roughly with trunk water potential minima, peak radiation occurred about two hours before water potential minima, and maximum vapor pressure deficits corresponded closely to water potential minima. Diurnal fluctuations in water potential of small understory branches, as determined by the pressure chamber, did not correlate well with weather factors. Seasonally, trunk water potential appeared to be highly correlated with fluctuations in vapor pressure deficit and less correlated with global radiation and wind. Soil factors such as matric potential and temperature were not correlated with trunk water potential. Correlations between water potential determined by the pressure chamber and environmental factors were not consistent. Pressure chamber values of water potential, however, did correlate roughly with trunk water potential during the latter half of the summer of 1971. By multiple regression analysis, a predictive equation was devised to predict trunk water potential on a daily and on a seasonal basis. With diurnal input data, radiation, vapor pressure deficit, and a transformation of vapor pressure deficit were significant variables. The model explained 81 percent of the diurnal variation in trunk water potential. Evaluation of the model with seasonal data input showed only one variable, vapor pressure deficit, highly significant. With seasonal data, 72 percent of the variation in trunk water potential was explained. Analysis of 18 rainstorms which occurred during two summers of study showed that roughly 0.25 cm of rain must fall before interception storage of a spruce canopy is satisfied and measurable amounts of rain can fall to the forest floor. Variability among sample catches of a given storm was great, apparently reflecting the irregular nature of the overmature spruce canopy. On the average, 96 percent of rainfall from storms between 0.0 0 and 0.13 cm, 70 percent between 0.13 and 1.3 cm, and 38 percent between 1.3 and 2.5 cm was intercepted. The influence of rain on soil matric potential was restricted to the first 45 cm of soil at the spruce plots with no substantial increase of matric potential before the onset of fall rains. The effect of rain on matric potential of soil in the meadow was more pronounced. The matric potential of the 5, 15, and 30 cm depths fluctuated greatly. A temporary increase in matric potential of these depths following summer storms was noted while more marked increases in matric potential were measured after heavier fall rains. The major conclusions made as a result of this study are (1) relative vapor pressure in the trunks of Engelmann spruce changes markedly from hour-to-hour and from day-to-day during the summer months, (2) trunk water potential as measured by thermocouple psychrometers is functionally related to atmospheric factors of radiation, wind, and vapor pressure deficit, (3) fluctuations in trunk water potential with weather factors imply a causal relation with transpiration, (4) precipitation during the summer months modifies soil matric potential-but only in the shallow profiles, (5) matric potential fluctuations in the meadow areas are extreme (from saturation to low as - 40 bars) and would impose a serious threat to the water economy of young Engelmann spruce seedlings established in such meadows, and (6) Peltier type thermocouple psychrometers are useful instruments for investigation of the soil-plant-atmosphere continuum in field situations.

In this thesis, I examine the variation in plant species richness along gradients of productivity and disturbance in grasslands and forest habitats in southern Sweden, and I compare the documented patterns with theoretical predictions. Moreover, I evaluate the relative importance of habitat quality and habitat configuration for the occurrence of field layer species in deciduous forests. Finally, I present a new method for the determination of the regional species pool. To examine regional and local variation in plant species richness, I gathered data on species composition in plots of different size (0.001 - 1000 m2) in three vegetation types (deciduous forests, dry grasslands and coastal meadows) in four regions of southern Sweden (Öland, Gotland, Småland and Uppland). As predicted by the species pool hypothesis, differences in small-scale species richness of deciduous forests and dry grasslands were correlated with differences in the size of the regional species pool. Moreover, among plots large-scale diversity was predictive of small-scale diversity. Species diversity showed a hump-shaped relationship with productivity in forests, and was related to environmental heterogeneity and the size of the 'habitat-specific' species pool. In the two types of grassland examined, grazed sites were richer in species than abandoned sites. Moreover, both species composition and the representation of plants with different life-history characteristics differed between grazed and abandoned sites. As predicted by the intermediate disturbance hypothesis, species richness was highest at intermediate levels of grazing in coastal meadows. However, all the above patterns were scale-dependent, and not observed at all plot sizes. The occurrence of field layer species in deciduous forests was more strongly related to habitat quality (mainly soil factors) than to habitat configuration (forest area and isolation). Across species, low seed production, clonal reproduction and habitat specificity were negatively associated with isolation.

Submitted by Jaqueline Silva (jtas29@gmail.com) on 2016-09-08T19:58:04Z No. of bitstreams: 2 Dissertação - Gabriel Eliseu Silva - 2014.pdf: 1496066 bytes, checksum: 022a464ffaf53a95f5e7c2aba78aeff4 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Approved for entry into archive by Jaqueline Silva (jtas29@gmail.com) on 2016-09-08T19:58:15Z (GMT) No. of bitstreams: 2 Dissertação - Gabriel Eliseu Silva - 2014.pdf: 1496066 bytes, checksum: 022a464ffaf53a95f5e7c2aba78aeff4 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2016-09-08T19:58:15Z (GMT). No. of bitstreams: 2 Dissertação - Gabriel Eliseu Silva - 2014.pdf: 1496066 bytes, checksum: 022a464ffaf53a95f5e7c2aba78aeff4 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2014-08-21 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / (Dynamics of the shrub-tree community in three areas of cerrado sensu stricto in the municipality of Jataí, southwest of Goiás). The aim of the study was to assess the changes in shrub-tree community in a range of approximately three years, involving changes in the structure and vegetation composition with soil factors and the fire. The study was conducted in three areas of “cerrado sentido restrito”, using a ten plots of 20 × 50m in each area. All shrub-tree individuals with DAS (diameter at the heigh of the ground) ≥ 5 cm in the first survey (T1) were plaquetados, estimated their heights and identified their species (2009 in BAT and LAJ, and 2010 in FRP). The second survey (T2) was carried out in 2012 in the area of LAJ and in 2013 in the other two areas (BAT and FRP). T2 survivors were re-measured and those who have to enter the inclusion criteria (recruits) were measured and plaquetados. T1 in BAT, it was found 70 species, 853 individuals and basal area of 8.75 m2. T2 is sampled-63 species, 601 individuals and basal area of 9.12 m2. In the interval between the two surveys (4.16 years) nine species disappeared and two joined the community. The diversity index of Shannon and Pielou evenness were 3.26 and 0.77, respectively, for T1. For T2, only the diversity changed, dropping to 3.16. The average annual mortality rate was 11.55% and the recruitment 2.4%. In LAJ met 83 species, 1391 individuals and basal area of 16.82 m2 in T1 and T2 is already sampled-87 species, 1503 individuals and basal area of 18.65 m2. In the period of 3.58 years, eight species entered four disappeared in the community. The diversity index was 3.62 at T1 and T2 3.65. The average annual mortality rate was 2.27% and 4.13% of recruitment. In FARP met 77 species, 1863 individuals and basal area of 10.87 m2 in T1, T2 and already sampled to 75 species, 1395 individuals and basal area of 10.1 m2. In the period of three years, seven species have disappeared and five joined the community. The diversity index was 3,62 at T1 and T2 3,65. For the evenness values were 0,8 for both surveys. The average annual mortality rate was 10,37% and 1,73% of recruitment. The three cerrado narrow sense fragments altered the species richness, the number of individuals and basal area, but no significant changes in the diversity index between the first and the second survey. This may be related to variations in wealth, depending on the species with few individuals. The highest mortality found for BAT and FRP may be related to the presence of fire, while for the LAJ the largest recruitment is associated with absence of disturbance. The change in density and growth of individuals can still be conditioned to the soil characteristics. In LAJ and BAT the clay soil, while allowing the establishment and growth of forest species and individuals susceptible to fire, in BAT, it is believed that the fire has acted as limiting changes in the structure, preventing the density of vegetation; and LAJ, the increased density and increased basal area possibly occurred in the absence of fire. In the FRP, it is suggested that any fire and the sandy soil can contribute to the limitation on structural changes and the wealth of the community. Thus, in the LAJ greater rate of recruitment in relation to the recorded mortality, may possibly be related to the absence of fire and soil characteristics, providing tree compaction stage and a possible succession of the community, indicating the formation of a cerradão. Regarding the areas of BAT and FARP the highest mortality rates in relation to recruitment may ester associated with the presence of fire, preventing the thickening in the community and keeping the cerrado vegetation type narrow sense. / (Dinâmica da comunidade arbustivo-arbórea de três áreas de cerrado sentido restrito no município de Jataí, sudoeste de Goiás). O objetivo do trabalho foi verificar as mudanças ocorridas na comunidade lenhosa em um intervalo aproximado de três anos, associando as alterações na estrutura e na composição vegetacionais com os fatores edáficos e o fogo. O estudo foi realizado em três áreas de cerrado sentido restrito, utilizando dez parcelas de 20 × 50m em cada área, onde foram amostrados todos os indivíduos lenhosos com DAS (diâmetro a altura do solo) ≥ 5 cm no primeiro levantamento (T1), plaquetados, estimados suas alturas e identificados suas espécies (2009 no BAT e na LAJ, e 2010 na FRP). O segundo levantamento (T2) foi realizado em 2012 na área da LAJ e em 2013 nas outras duas áreas (BAT e FRP). Em T2 os sobreviventes foram remedidos e aqueles que passaram a entrar no critério de inclusão (recrutas) foram mensurados e plaquetados. Em T1 no BAT, encontrou-se 70 espécies, 853 indivíduos e área basal de 8,75 m2. Em T2 amostrou-se 63 espécies, 601 indivíduos e área basal de 9,12 m2. No intervalo entre os dois levantamentos (4,16 anos) nove espécies desapareceram e duas ingressaram na comunidade. O índice de diversidade de Shannon e a equabilidade de Pielou foram 3,26 e 0,77, respectivamente, para T1. Para T2, apenas a diversidade alterou, caindo para 3,16. A taxa média anual de mortalidade foi 11,55% e a de recrutamento 2,4%. Na LAJ encontrou-se 83 espécies, 1391 indivíduos e área basal de 16,82 m2 em T1, e já em T2 amostrou-se 87 espécies, 1503 indivíduos e área basal de 18,65 m2. No período de 3,58 anos, oito espécies ingressaram e quatro desapareceram na comunidade. O índice de diversidade em T1 foi de 3,62 e em T2 3,65. A taxa média anual de mortalidade foi de 2,27% e a de recrutamento 4,13%. Na FARP encontrou-se 77 espécies, 1863 indivíduos e área basal de 10,87 m2 em T1, e já em T2 amostrou-se 75 espécies, 1395 indivíduos e área basal de 10,1 m2. No período de 3,0 anos, sete espécies desapareceram e cinco ingressaram na comunidade. O índice de diversidade em T1 foi de 3,62 e em T2 3,65. Para a equabilidade os valores foram 0,8 para ambos os levantamentos. A taxa média anual de mortalidade foi de 10,37% e a de recrutamento 1,73%. Os três fragmentos de cerrado sentido restrito alteraram a riqueza de espécies, o número de indivíduos e área basal, porém não houve mudanças consideráveis nos índices de diversidade entre o primeiro e o segundo levantamento. Isso pode estar relacionado à variação da riqueza, em função das espécies que apresentaram poucos indivíduos. As maiores mortalidades encontradas para a BAT e FRP podem estar relacionadas à presença do fogo, enquanto para a LAJ o maior recrutamento esteja associado à ausência da perturbação. A alteração na densidade e o crescimento dos indivíduos podem estar condicionados ainda às características do solo. Na LAJ e no BAT o solo argiloso, apesar de possibilitar o estabelecimento e crescimento dos indivíduos de espécies florestais e sensíveis ao fogo, no BAT, acredita-se que o fogo tem atuado como limitante nas alterações da estrutura, impedindo o adensamento da vegetação; e na LAJ, o aumento da densidade e incremento em área basal, possivelmente ocorreu devido à ausência de queimadas. Já na FRP, sugere-se que o fogo eventual e o solo arenoso possam contribuir com a limitação nas alterações estruturais e na riqueza da comunidade. Assim, na LAJ a maior taxa de recrutamento registrada em relação à de mortalidade, possivelmente pode estar relacionada à ausência do fogo e às características do solo, proporcionando o adensamento arbóreo e um possível estágio sucessional da comunidade, indicando a formação de um cerradão. Em relação às áreas do BAT e da FARP as maiores taxas de mortalidade em relação às de recrutamento podem estar associadas à presença de queimadas, impedindo o adensamento na comunidade e mantendo a fitofisionomia de cerrado sentido restrito.