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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.
121

Floração e frutificação de Myrtaceae de floresta atlântica : limitações ecológicas e filogenéticas /

Gressler, Eliana. January 2005 (has links)
Orientador: Leonor Patrícia Cerdeira Morellato / Banca: Marco Antônio Portugal Luttembarck Batalha / Banca: Isabel Cristina Sobreiro Machado / Resumo: São poucos os estudos que abordam a floração e frutificação em espécies filogeneticamente relacionadas. Myrtaceae é uma das famílias de plantas mais abundantes nas matas brasileiras, em especial na floresta pluvial atlântica. O presente estudo teve como objetivos principais: 1) analisar a fenologia reprodutiva de 38 espécies de Myrtaceae, verificando os padrões fenológicos, relação com os fatores climáticos e previsibilidade das fenofases; e 2) avaliar as teorias propostas para explicar a fenologia de espécies aparentadas e a relação entre a fenologia e o tamanho do fruto. O estudo foi desenvolvido em área de floresta atlântica no Parque Estadual Intervales, Base Saibadela (24°14'08"S e 48°04'42"W), município de Sete Barras, estado de São Paulo, Brasil. As fenofases botão, antese, fruto imaturo e maduro foram observadas mensalmente durante seis anos nãoconsecutivos (abril/1994 a março/1997 e abril/1999 a março/2002) em 285 indivíduos. As maiores porcentagens de indivíduos e espécies apresentando botões e flores abertas ocorreram sempre na estação mais quente e chuvosa (outubro a março), e produzindo frutos imaturos e maduros principalmente ao longo da estação menos quente e úmida (abril a setembro). As correlações de Spearman foram significativas entre a floração e o comprimento do dia e a temperatura, e correlações significativas foram raras entre a frutificação e o clima. A análise estatística circular mostrou que as datas de início e pico das fenofases reprodutivas em Myrtaceae foram sazonais para a maioria dos anos estudados. Todas as fenofases apresentaram valores altos de previsibilidade de ocorrência... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: There are few studies approaching flower and fruit patterns among phylogenetically related species. Myrtaceae is one of the most abundant plant families in the Brazilian forests, especially in the Atlantic Rain Forest. The present study had the main objectives: 1) to analyze the reproductive phenology of 38 Myrtaceae species, checking the phenological patterns, the relationship with the climatic factors and the predictability of the phenophases; and 2) to evaluate the proposed theories to explain the phenology of related species and the relation between phenology and fruit size. The study was carried out in an Atlantic forest area at Parque Estadual Intervales, Base Saibadela (24°14'08"S and 48°04'42"W), municipality of Sete Barras, São Paulo State, Brazil. The phenophases bud flower, open flowers, unripe and ripe fruits were observed monthly for six nonconsecutive years (April/1994 to March/1997 and April/1999 to March/2002) in 285 individuals. The largest percentages of individuals and species presenting buds and open flowers always occurred during the wetter and hotter season (October to March), and unripe and ripe fruits were produced mainly over the less humid and colder season (April to September). The Spearman’ correlations were significant between flowering and the day length and the temperature, and significant correlations were rare between fruiting and climate. The circular statistical analysis showed that the first date and peak date of the reproductive phenophases in Myrtaceae were seasonal for most of the years. All the phenophases showed high predictability scores... (Complete abstract, click electronic adress below) / Mestre
122

Efeito de épocas de semeadura no desenvolvimento e produtividade do trigo (Triticum aestivum L.) na região de Pato Branco-PR

Civiero, João Carlos 04 March 2010 (has links)
Para cada subperíodo de desenvolvimento do trigo são produzidos diferentes órgãos, estando a formação do número destes órgãos dependente da duração de cada subperíodo. A temperatura, o fotoperíodo e a vernalização contribuem significativamente para a determinação da taxa de desenvolvimento da duração desses subperíodos. Neste contexto, este estudo objetivou apresentar um mapeamento da variabilidade temporal dos fatores de ambiente em Pato Branco, e discutir suas possíveis implicações para a expressão do potencial de rendimento de grãos de trigo. Também, buscou-se analisar os períodos do ano que ofereçam as melhores condições de ambiente, em termos de temperatura e radiação solar para a definição do aumento dos componentes de rendimento e desenvolvimento da cultura, buscando as melhores épocas de semeadura para as cultivares em estudo. O experimento foi conduzido durante os anos de 2008 e 2009 na Estação Experimental do Curso de Agronomia da UTFPR, em Pato Branco-PR (26º10’ S; 52º41’W e 750 m). O delineamento utilizado foi de blocos ao acaso, com três repetições no primeiro ano e com quatro repetições no segundo ano, em esquema bifatorial (cultivares BRS 208, BRS 220 e BRS Guamirim x sete épocas de semeaduras). As semeaduras foram efetuadas no período de: 06/05, 17/05, 31/05, 14/06, 28/06, 12/07 e 26/07 para o ano de 2008 e 02/05, 16/05, 02/06, 13/06, 30/06, 13/07, 24/07 para o ano de 2009. Assim, o presente estudo, inicialmente, determinou os diferentes subperíodos de desenvolvimento dos genótipos de trigo testados, assim delimitados: SE-EM, EM-DA, DA-ET, ET-AN, AN-MF. Os estádios de duplo anel e de espigueta terminal foram determinados morfologicamente, em 3 colmos colhidos a cada 48 horas. Para determinação da maturação fisiológica, cinco espiguetas centrais de três espigas, totalizando 15 espiguetas por parcela foram amostradas a cada 72 horas e levadas a estufa, para após serem pesadas, considerando a maturação fisiológica quando apresentavam massa constante. Também, foram avaliadas as implicações do QF no rendimento dos genótipos testados. Foram analisadas as variáveis: altura de planta, massa seca da parte aérea e espigas, índice de colheita e os componentes de rendimento (espigas m-2, espiguetas espiga-1, grãos espiguetas-1 e massa de mil grãos). Conclui-se que não foi possível observar efeito claro, do quociente fototermal (QF) sobre a definição dos componentes de rendimento. Para o ano de 2008 o subperíodo AN-MF, esteve associado com o aumento do rendimento de grãos, somente para a cultivar BRS 220, correlacionando-se posteriormente com o aumento do QF e repercutindo no aumento da massa de grãos. Para o ano de 2009 não foi possível observar correlações do rendimento de grãos com a soma térmica. Entretanto foi verificado entre o QF e a soma térmica do subperíodo AN-MF, para a cultivar BRS Guamirim. Quanto ao rendimento de grãos, esse diferiu entre os anos de alta precipitação (2009) com relação ao ano de baixa precipitação (2008). As semeaduras realizadas nas datas de 30 de maio e 14 de junho ocasionaram os maiores rendimentos de grãos, para os anos de 2008 e 2009, respectivamente. / For each subperiod development of wheat are produced in different organs and is the formation of the number of these organs dependent on the duration of each subperiod. The temperature of the vernalization photoperiod and contribute significantly to determine the rate of development of the length of such sub-periods. In this context, this study aims to map the temporal variability of environmental factors in Pato Branco, and discuss its possible implications for the expression of yield potential of wheat. Also, we attempted to analyze the periods of the year that offer the best environmental conditions, in terms of temperature and solar radiation to define the increase in yield components and development of culture, seeking the best seasons to the cultivars studied. The experiment was conducted during the years 2008 and 2009 at the Experimental Station of Agronomy Course UTFPR in Pato Branco-PR (26º10'S; 52º41'W and 750 m). The experimental design was randomized blocks with three replications in the first year and four replications in the second year in a factorial scheme (BRS 208, BRS 220 and BRS Guamirim x seven sowing dates). The sowings were made in the period of: 06/05 17/05 31/05 14/06 28/06 12/07 and 26/07 for the year 2008 and 02/05 16/05, 02 / 06 13/06 30/06 13/07 24/07 for the year 2009. Thus, this study initially determined the different developmental sub periods of the wheat genotypes tested, so defined: SE-EM, EM-DA, DA-ET, ET-AN, AN-MF. The double ring stages and terminal spikelet were determined morphologically, 3 stalks harvested every 48 hours. To determine the physiological maturity, five central spikelets of three spikes, with 15 spikelets per plot were sampled every 72 hours and brought the oven, for after being weighed, considering the physiological maturity when they had constant weight. Also, we assessed the implications of QF yield of genotypes. The variables analyzed were: plant height, shoot dry weight and ear, harvest index and yield components (spikes m-2, spikelets spike-1, grains spikelet-1 and thousand grain weight). It is not clear effect was observed, photothermal quotient (QF) on the definition of component performance. For the year 2008 the subperiod AN-MF, was associated with increased grain yield, only for BRS 220, correlating with the later increase in QF and reflecting the increase in grain mass. For the year 2009 was not possible to observe correlations of yield with the thermal. However it was observed between the QF and the thermal sub-period of the AN-MF, for BRS Guamirim. The grain yield, this differed between the years of high rainfall (2009) with respect to years of low precipitation (2008). Cultivation procedures conducted on the dates of May 30 and June 14 showed higher grain yields for the years 2008 and 2009, respectively.
123

Efeito de épocas de semeadura no desenvolvimento e produtividade do trigo (Triticum aestivum L.) na região de Pato Branco-PR

Civiero, João Carlos 04 March 2010 (has links)
Para cada subperíodo de desenvolvimento do trigo são produzidos diferentes órgãos, estando a formação do número destes órgãos dependente da duração de cada subperíodo. A temperatura, o fotoperíodo e a vernalização contribuem significativamente para a determinação da taxa de desenvolvimento da duração desses subperíodos. Neste contexto, este estudo objetivou apresentar um mapeamento da variabilidade temporal dos fatores de ambiente em Pato Branco, e discutir suas possíveis implicações para a expressão do potencial de rendimento de grãos de trigo. Também, buscou-se analisar os períodos do ano que ofereçam as melhores condições de ambiente, em termos de temperatura e radiação solar para a definição do aumento dos componentes de rendimento e desenvolvimento da cultura, buscando as melhores épocas de semeadura para as cultivares em estudo. O experimento foi conduzido durante os anos de 2008 e 2009 na Estação Experimental do Curso de Agronomia da UTFPR, em Pato Branco-PR (26º10’ S; 52º41’W e 750 m). O delineamento utilizado foi de blocos ao acaso, com três repetições no primeiro ano e com quatro repetições no segundo ano, em esquema bifatorial (cultivares BRS 208, BRS 220 e BRS Guamirim x sete épocas de semeaduras). As semeaduras foram efetuadas no período de: 06/05, 17/05, 31/05, 14/06, 28/06, 12/07 e 26/07 para o ano de 2008 e 02/05, 16/05, 02/06, 13/06, 30/06, 13/07, 24/07 para o ano de 2009. Assim, o presente estudo, inicialmente, determinou os diferentes subperíodos de desenvolvimento dos genótipos de trigo testados, assim delimitados: SE-EM, EM-DA, DA-ET, ET-AN, AN-MF. Os estádios de duplo anel e de espigueta terminal foram determinados morfologicamente, em 3 colmos colhidos a cada 48 horas. Para determinação da maturação fisiológica, cinco espiguetas centrais de três espigas, totalizando 15 espiguetas por parcela foram amostradas a cada 72 horas e levadas a estufa, para após serem pesadas, considerando a maturação fisiológica quando apresentavam massa constante. Também, foram avaliadas as implicações do QF no rendimento dos genótipos testados. Foram analisadas as variáveis: altura de planta, massa seca da parte aérea e espigas, índice de colheita e os componentes de rendimento (espigas m-2, espiguetas espiga-1, grãos espiguetas-1 e massa de mil grãos). Conclui-se que não foi possível observar efeito claro, do quociente fototermal (QF) sobre a definição dos componentes de rendimento. Para o ano de 2008 o subperíodo AN-MF, esteve associado com o aumento do rendimento de grãos, somente para a cultivar BRS 220, correlacionando-se posteriormente com o aumento do QF e repercutindo no aumento da massa de grãos. Para o ano de 2009 não foi possível observar correlações do rendimento de grãos com a soma térmica. Entretanto foi verificado entre o QF e a soma térmica do subperíodo AN-MF, para a cultivar BRS Guamirim. Quanto ao rendimento de grãos, esse diferiu entre os anos de alta precipitação (2009) com relação ao ano de baixa precipitação (2008). As semeaduras realizadas nas datas de 30 de maio e 14 de junho ocasionaram os maiores rendimentos de grãos, para os anos de 2008 e 2009, respectivamente. / For each subperiod development of wheat are produced in different organs and is the formation of the number of these organs dependent on the duration of each subperiod. The temperature of the vernalization photoperiod and contribute significantly to determine the rate of development of the length of such sub-periods. In this context, this study aims to map the temporal variability of environmental factors in Pato Branco, and discuss its possible implications for the expression of yield potential of wheat. Also, we attempted to analyze the periods of the year that offer the best environmental conditions, in terms of temperature and solar radiation to define the increase in yield components and development of culture, seeking the best seasons to the cultivars studied. The experiment was conducted during the years 2008 and 2009 at the Experimental Station of Agronomy Course UTFPR in Pato Branco-PR (26º10'S; 52º41'W and 750 m). The experimental design was randomized blocks with three replications in the first year and four replications in the second year in a factorial scheme (BRS 208, BRS 220 and BRS Guamirim x seven sowing dates). The sowings were made in the period of: 06/05 17/05 31/05 14/06 28/06 12/07 and 26/07 for the year 2008 and 02/05 16/05, 02 / 06 13/06 30/06 13/07 24/07 for the year 2009. Thus, this study initially determined the different developmental sub periods of the wheat genotypes tested, so defined: SE-EM, EM-DA, DA-ET, ET-AN, AN-MF. The double ring stages and terminal spikelet were determined morphologically, 3 stalks harvested every 48 hours. To determine the physiological maturity, five central spikelets of three spikes, with 15 spikelets per plot were sampled every 72 hours and brought the oven, for after being weighed, considering the physiological maturity when they had constant weight. Also, we assessed the implications of QF yield of genotypes. The variables analyzed were: plant height, shoot dry weight and ear, harvest index and yield components (spikes m-2, spikelets spike-1, grains spikelet-1 and thousand grain weight). It is not clear effect was observed, photothermal quotient (QF) on the definition of component performance. For the year 2008 the subperiod AN-MF, was associated with increased grain yield, only for BRS 220, correlating with the later increase in QF and reflecting the increase in grain mass. For the year 2009 was not possible to observe correlations of yield with the thermal. However it was observed between the QF and the thermal sub-period of the AN-MF, for BRS Guamirim. The grain yield, this differed between the years of high rainfall (2009) with respect to years of low precipitation (2008). Cultivation procedures conducted on the dates of May 30 and June 14 showed higher grain yields for the years 2008 and 2009, respectively.
124

Entomofauna visitante das flores de Lippia alba (Mill.) N.E. Brown (Lamiales, Verbanaceae) em Juiz de Fora, Minas Gerais

Venâncio, Daniele de Fátima Alves 23 April 2010 (has links)
Submitted by Renata Lopes (renatasil82@gmail.com) on 2016-09-30T18:19:22Z No. of bitstreams: 1 danieledefatimaalvesvenancio.pdf: 2134592 bytes, checksum: 0806519cff794316a101d8023b04ca1e (MD5) / Approved for entry into archive by Diamantino Mayra (mayra.diamantino@ufjf.edu.br) on 2016-10-03T15:16:19Z (GMT) No. of bitstreams: 1 danieledefatimaalvesvenancio.pdf: 2134592 bytes, checksum: 0806519cff794316a101d8023b04ca1e (MD5) / Made available in DSpace on 2016-10-03T15:16:19Z (GMT). No. of bitstreams: 1 danieledefatimaalvesvenancio.pdf: 2134592 bytes, checksum: 0806519cff794316a101d8023b04ca1e (MD5) Previous issue date: 2010-04-23 / Lippia alba (Mill) N.E. Brown (Verbenaceae) é um arbusto aromático de interesse na fitoterapia devido às suas propriedades medicinais. Os conhecimentos sobre os aspectos reprodutivos da espécie são importantes para a exploração sustentável. O objetivo do presente estudo foi verificar a fenologia floral, a morfologia polínica, a entomofauna visitante das flores e a influência dos fatores climáticos na frequência de visitas nas flores de Lippia alba. O trabalho foi desenvolvido na Estação Experimental de Cultivo e Manutenção de Plantas da UFJF, no município de Juiz de Fora, MG durante o período de dezembro de 2008 a novembro de 2009. Foram feitas observações sobre a fenologia floral e descrição morfológica dos grãos de pólen, além disso, realizou-se mensalmente o levantamento dos visitantes florais de L. alba no período de 6h às 18h. A floração de L. alba ocorreu durante todo o ano. A antese floral é diurna e dura cinco dias. O guia nas flores foi visível até o terceiro dia. O estigma permanece recoberto por uma camada úmida e viscosa até o terceiro dia. O número médio de inflorescências por planta foi de 44,4 ± 38,29. Cada inflorescência possui em média 7,1 ± 6,9 flores. Os grãos de pólen apresentam tamanho médio, sendo classificados como isopolares, oblato-esferoidais, 3-colporados (raro, 4-colporados), de superfície tectado-perfurada, constrição mediana e endoabertura lalongada. Dentre os insetos amostrados, a ordem Hymenoptera apresentou o maior percentual de visitas (84,71%), seguida de Lepidoptera (11%), Thysanoptera (2,12%), Diptera (2,08%) e Hemiptera – Heteroptera (0,09%). Foram registradas sessenta e três espécies, com maior frequência de visitação entre as 10h e 14h, sendo observado correlação significativa entre a freqüência de visitas e os fatores climáticos nos diferentes horários do dia (luminosa, r= 0.56, p<0.0001; temperatura, r=0.69, p<0.0001 e umidade relativa do ar, r= -0.55, p<0.0001). A estação chuvosa apresentou número significativamente maior de espécies visitantes (P<0,05) e maior frequência de visitação. A planta mostrou-se preferencialmente melitófila, devido à predominância de abelhas visitantes de suas flores. A abelha Apis mellifera foi considerada o principal visitante devido à sua constância e maior frequência. Como L. Alba floresce durante todo o ano, os autores sugerem a sua utilização como recurso floral para as abelhas de interesse apícola. / Lippia alba (Mill) N.E. Brown (Verbenaceae) is a aromatical shrub used in herbal therapy, due to its medicinal properties. The knowledgement about this species reproductive aspects is usefull to make its sustainable exploration. So, The objective of the present study was to verify the floral phenology, pollen morphology, flowering entomofauna and the influence of climatic factors in relation to the frequency of visits in flowers of L. alba. The work was developed in the Experimental Station of Plants Culture and Maintenance of UFJF, in the municipality of Juiz de Fora, MG, from december of 2008 to november of 2009. Observations were made on the floral phenology and morphological description of the pollen grains, also held monthly survey of insect floral visitors of L. alba in the period of 6 am to 6 pm. Flowering of L. alba occurred throughout the year. The anthesis was diurnal and each flower had a duration of five days. The guide was visible in the flowers until the third day. The stigma remained wet and sticky until the third day. The average number of inflorescences per plant was 44.4 ± 38.29. Each inflorescence had on average 7.1 ± 6.9 flowers. Pollen grains had average size, from they were classified as isopolar, oblate spheroidal, 3-colporate (rare, 4colporate), surface pierced and tectated, with a median constriction and endoaperture lalongate. Hymenoptera showed the highest percentage of visits (84.71%), between the insects sampled, followed by Lepidoptera (11.00%), Thysanoptera (2.12%), Diptera (2.08%) and Hemiptera - Heteroptera (0.09%). Sixty three species were recorded, with greater frequency of visitation from10 am and 2 pm, and a significant correlation between the frequency of visits and the climatic factors was observed at different times of day (light, r = 0,56; p <0,0001; temperature, r = 0,69; p < 0,0001 and relative humidity of air, r = -0,55; p <0,0001). The rainy season presented a significantly higher number of species visitors (P <0.05) and increased frequency of visitation. The plant showed to be preferentially melittophilous, due to the predominance of bees visitors of the flowers. The honeybee Apis mellifera was considered the main visiting because of its constancy and frequency in the L. alba flowers. The authors suggest the use of this species as a constant source of pollen and nectar, throughout all the year, perfect to beekeeping services.
125

A questão das estâncias climáticas no Estado de São Paulo : Morungaba como estudo de caso / The question of climate resort's in the State of São Paulo : Morungaba as a case study

Pinto, Silvio Luiz Cardoso, 1963- 05 August 2014 (has links)
Orientador: Lauro Luiz Francisco Filho / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Civil, Arquitetura e Urbanismo / Made available in DSpace on 2018-08-25T16:54:14Z (GMT). No. of bitstreams: 1 Pinto_SilvioLuizCardoso_M.pdf: 17830648 bytes, checksum: bd07737a58001d92e34de2595198cd44 (MD5) Previous issue date: 2014 / Resumo: Este trabalho aborda a formação das primeiras Estâncias no Estado de São Paulo, e os fatores que inicialmente determinaram a escolha de um município como Estância. As condições sociais que precederam a necessidade, por parte do Governo do Estado, de eleger determinados municípios, a fim de torná-los Estâncias Sanitárias (primeira forma de distinção). Serão abordados aspectos históricos, sociais, condições sanitárias bem como fatores econômicos, e como estes vetores influenciaram o desenvolvimento do conceito "Estância". A evolução dos critérios e formas de classificação. O cenário climático presente no Estado de São Paulo, e sua condição de transição dentro do panorama nacional será discutido, buscando entender como sua relevância e distinção pode ser questionada, enquanto fator determinante na classificação do município. Outros fatores que relacionam o desenvolvimento da indústria do turismo com o desenvolvimento municipal serão analisados de forma criteriosa. O Plano Diretor proposto por Ruy Ohtake a administração pública morungabense será apresentado e discutido dentro do contexto da evolução urbana do município, que ainda hoje, enfrenta dificuldades para se definir entre industrial e turístico / Abstract: This paper addresses the formation of the first resorts in the state of São Paulo, and the factors that initially led to the choice of a municipality as Estancia. The social conditions that preceded the need for the State Government, to elect certain municipalities in order to make them Resorts Sanitary (first form of distinction). Historic social aspects, health conditions and economic factors, and how these vectors influenced the development of the concept "Stanza" will be addressed. The development of criteria and forms of classification. The present climate scenario in the State of São Paulo, and its transition condition within the national scene will be discussed, seeking to understand how its relevance and distinction may be questioned, as the determining factor in the rating of the municipality. Other factors relate to the development of the tourism industry to municipal development will be carefully analyzed. The Master Plan proposed by Ruy Ohtake morungabense the public administration will be analyzed and discussed within the context of urban evolution of the city, which still faces difficulties in defining between industrial and tourism / Mestrado / Arquitetura, Tecnologia e Cidade / Mestre em Arquitetura, Tecnologia e Cidade
126

Developing an understanding of the drivers of bat activity patterns relevant to wind turbines

Thwaits, Tiffany Edan January 2014 (has links)
The increasing number of proposed wind farm developments in South Africa provides an immediate reason to assess bat activity and diversity, with the expectation of developing measures to mitigate for negative impacts. The overall aim of this thesis was contribute to an understanding of the drivers of bat activity, relevant to wind turbines, and to determine what factors (exogenous – environmental, or endogenous – intrinsic physiological processes) contributed to observed bat activity patterns, at the Metrowind Van Stadens Wind Farm in the Eastern Cape of South Africa. A combination of active (mist netting) and passive (acoustic) bat monitoring techniques were used to determine free-ranging bat activity patterns (Chapter 3). A total of 889 bat passes were recorded over 323 detector nights from the beginning of May 2012 to the end of December 2012. The Cape serotine bat (82 per cent) and the Egyptian free-tailed bat (97 per cent) made up the majority of all bat passes recorded on site. Large variations in bat activity per month and per hour were apparent, with bat activity peaking in May 2012 and during the first few hours after sunset (18:00-23:00). Patterns in nightly, free-ranging bat activity at the site were modelled against various environmental conditions. Month, temperature, wind speed and an interaction between month and rainfall were the most significant predictors of bat activity, explaining 80 per cent of the variation observed on free-ranging bat activity patterns. A total of eight Cape serotine bats (Table 4.1.) were caught in mist nets on site and changes in the resting metabolic rate (RMR) of torpid (n = 6), and normothermic (n = 2) bats, over a 24 hr period, were measured and used to predict free-ranging Cape serotine bat activity (Chapter 4). Cape serotine bats showed a high proclivity for torpor in the laboratory and peaks in RMR were observed at 18:00 (0.89 ± 0.95 VO2 mℓ.g-1.hr-1) and again from 20:00-21:00 (0.89 ± 0.91 VO2 mℓ.g-1.hr-1). Peaks in RMR of torpid individuals coincided with peaks in the average hourly free-ranging activity of the Cape serotine bat, and RMR explained 33 per cent of the variation and was a good predictor of free-ranging bat activity (R2 = 0.2914). This study showed that both exogenous (Chapter 3) and endogenous (Chapter 4) factors drive bat activity in the wild. Although this dissertation was not intended for wind turbine management, the information presented on the biology and activity of bats is important for managing interactions between bats and wind turbines. By determining what factors influence bat activity, we are able to predict when bats will be most active and thus can develop mitigation measures to reduce the potential impacts that wind turbines will have on the bat community. In order to conserve bats and reduce potential bat fatalities from occurring at the site, mitigation measures should be concentrated to those times when bats are most active (May and during the first few hours after sunset – 18:00 to 22:00).
127

Biofuel, land-use tradeoffs and livelihoods in Southern Africa

Von Maltitz, Graham Paul January 2014 (has links)
The rapid expansion of biofuel projects in southern Africa creates an opportune issue against which to examine land-use tradeoffs within the areas of customary land tenure. For this an ecosystems services approach is used. Jatropha curcas (L), a perennial oilseed plant which has been the key focus of most of the region’s biofuel expansion to date is used as the focus biofuel crop for which case study data were obtained from Malawi, Mozambique, Zambia and South Africa. Despite the initial enthusiasm for jatropha, most projects have proven less successful than hoped, and many have collapsed. A few are, however, still showing signs of possible success and it is two of these that form the basis of the case studies. Hugely complex tradeoffs are involved when considering biofuel as a land-use option for communal areas. They range from global impacts such as biodiversity and global climate forcing, through national concerns of rural development, national food security and national fuel security, to local household concerns around improving livelihoods. Land that is converted to biofuel needs to be removed from some previous use, and in the southern African case it is typically woodlands and the multitude of services they provide, that suffer. The nature of the tradeoffs and the people affected change over the scale under consideration. For the local farmer it is only the local issues that are of concern, but national and global forces will change the policy environment and lead to new types of development such as biofuels. Change is inevitable, and in all developments there are likely to be both winners and losers. It is clear that the impacts arising from biofuel are situation dependent, and each community and location has unique social and environmental considerations that need to be taken into account. In the case of jatropha the final realised yield and the economic returns that this can generate, will be of critical importance and remain one of the main uncertainties. There are promising signs that under certain circumstances the balance of benefits from jatropha biofuel may be positive, but if implemented incorrectly or in the wrong place, there is extensive evidence of total project failure. It is clear that evidence-based data and assessment tools are needed to assist communities, developers and government departments to make sound decisions around biofuel (or other land-use based) development. A number of such tools are suggested in the thesis. Both the use of large-scale plantations or small-scale farmer centred projects have their advantages and disadvantages. It is probable that in the correct circumstances either can work. However, large-scale plantations can have huge negative social and environmental consequences if poorly implemented. Small-scale projects, though improving livelihoods, are unlikely to take the farmers out of poverty. Tradeoffs from any land-use change are inevitable. Empirical data on biofuel impacts on the environment and society are needed for the development of sound policy. A favourable policy environment can ensure that positive benefits from biofuel are obtained, whilst minimising negative impacts. To develop this policy means that southern African countries will have to clearly understand what they wish to achieve from biofuel, as well as having a clear understanding of impacts from biofuel implementation. Sound scientific knowledge needs to underpin this process. For instance governments may wish to increase the ratio of small-scale to large-scale plantation to increase the developmental benefits, ensure biofuel is used to promote national fuel security rather than being exported, or develop a medium-scale farming sector which can help move farmers out of poverty and assist in developing a market surplus of agricultural commodities. Analysing impacts from biofuel expansion is a complex and multi-dimensional problem and as such will require multi-criteria analysis tools to develop solutions. Global, national and local tradeoffs must all be considered. In addition a wide range of stakeholders are involved and participatory processes may be needed to capture their inputs. Tools to better analyse impacts, specifically at the local level are needed. These local results need to feed into national level economic assessments. The cost of biofuel introduction should be considered against the costs of not implementing biofuel, realising that doing nothing also has a cost and long-term impact. Third-party certification provides a useful tool for shifting costs of ensuring compliance with social and environmental legislation, from the state to biofuel companies. In addition ongoing monitoring and evaluation of existing projects is needed to learn from successes and failures, to identify unintended consequences, and to increase the resilience of projects, community livelihoods and the national economy. This will have to be supplemented with additional focused and ongoing research.
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A method of detecting reaction to environmental influence by recording circadian activity, using the flagfish Jordanella floridae

Kano, Robert Matsuo 01 January 1974 (has links)
This paper investigates a means of detecting the reaction of aquatic vertebrates to environmental change by recording behavioral patterns within the diurnal activity. An apparatus measuring the activity of Jordanella floridae, Goode and Bean, using a photoelectric sensor system is described. Individual sensors monitored specific areas of the test aquarium that had special significance to the fish in the way of a particular behavioral category. An event recorder documented the breakage of light beams, giving continuous and accurately timed data of activity. Two distinct patterns of activity were recognized; a control, or typical, pattern, and a pattern resulting from the administration of a large (10°C) change in environmental temperature. Modifications in the diurnal behavior were consistent with reactions that could be adaptive for the species under similar conditions in nature.
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Mountain Glacier Change Across Regions and Timescales

Maurer, Joshua January 2020 (has links)
Mountain glaciers have influenced the surface of our planet throughout geologic time. These large reservoirs of water ice sculpt alpine landscapes, regulate downstream river flows, perturb climate-tectonic feedbacks, contribute to sea level change, and guide human migration and settlement patterns. Glaciers are especially relevant in modern times, acting as buffers which supply seasonal meltwater to densely populated downstream communities and support economies via hydropower generation. Anthropogenic warming is accelerating ice loss in most glacierized regions of the world. This has sparked concerns regarding water resources and natural hazards, and placed glaciers at the forefront of climate research. Here we provide new observations of glacier change in key mountain regions to quantify rates of ice loss, better understand climate drivers, and help establish a more unified framework for studying glacier change across timescales. In Chapter 1 we use seismic observations, numerical modeling, and geomorphic analysis to investigate a destructive glacial lake outburst flood (GLOF) which occurred in Bhutan. GLOFs are a substantial hazard for downstream communities in many vulnerable regions. Yet key aspects of GLOF dynamics remain difficult to quantify, as in situ measurements are scarce due to the unpredictability and remote source locations of these events. Here we apply cross-correlation based seismic analyses to track the evolution of the GLOF remotely (~100 km from the source region), use the seismic observations along with eyewitness reports and a downstream gauge station to constrain a numerical flood model, then assess geomorphic change and current state of the unstable lakes via satellite imagery. Coherent seismic energy is evident from 1 to 5 Hz beginning approximately 5 hours before the flood impacted Punakha village, which originated at the source lake and advanced down the valley during the GLOF duration. Our analysis highlights potential benefits of using real-time seismic monitoring to improve early warning systems. The next two chapters in this work focus on quantifying multi-decadal glacier ice loss in the Himalayas. Himalayan glaciers supply meltwater to densely populated catchments in South Asia, and regional observations of glacier change are needed to understand climate drivers and assess impacts on glacier-fed rivers. Here we utilize a set of digital elevation models derived from cold war–era spy satellite film and modern stereo satellite imagery to evaluate glacier responses to changing climate over the last four decades. In Chapter 2 we focus on the eastern Himalayas, centered on the Bhutan–China border. The wide range of glacier types allows for the first mass balance comparison between clean, debris, and lake-terminating (calving) glaciers in the area. Measured glaciers show significant ice loss, with statistically similar mass balance values for both clean-ice and debris-covered glacier groups. Chapter 3 extends the same methodology to quantify glacier change across the entire Himalayan range during 1975–2000 and 2000–2016. We observe consistent ice loss along the entire 2000-km transect for both intervals and find a doubling of the average loss rate during 2000–2016 compared to 1975–2000. The similar magnitude and acceleration of ice loss across the Himalayas suggests a regionally coherent climate forcing, consistent with atmospheric warming and associated energy fluxes as the dominant drivers of glacier change. Chapter 4 investigates millennial-scale glacier changes during the Late Glacial period (15-11 ka). Here we present a high-precision beryllium-10 chronology and geomorphic map from a sequence of well-preserved moraines in the Nendaz valley of the western European Alps, with the goal to shed light on the timing and magnitude of glacier responses during an interval of dramatic natural climate variability. Our chronology brackets a coherent glacier recession through the Younger Dryas stadial into the early Holocene, similar to glacier records from the southern hemisphere and a new chronology from Arctic Norway. These results highlight a general agreement between mountain glacier changes and atmospheric greenhouse gas records during the Late Glacial. In Chapter 5 we use a numerical glacier model to simulate glacier change across a typical alpine region in the European Alps. Model results suggest that shorter observational timespans focused on modern periods (when glaciers are far from equilibrium and undergoing rapid change) exhibit greater spatial variability of mean annual ice thickness changes, compared to intervals which extend further back in time (to include decades when climate was more stable). The model agrees with multi-decadal satellite observations of glacier change, and clarifies the positive correlation between glacier disequilibrium and spatial variability of glacier mass balance. This relationship should be taken into account in regional glacier studies, particularly when analyzing recent spatial patterns of ice loss. Advances made in this work are of practical value for societies vulnerable to glacier change. This includes potential improvements to GLOF early warning systems via seismic monitoring, better constraints on glacier-sourced water scenarios in South Asia, strengthened understanding of long-term glacier responses to baseline natural climate variability, and a clarified relationship between glacier disequilibrium and spatial variability of ice loss. When placed within a global context, our observations highlight the correlation between regional mountain glacier change and greenhouse gas forcing through time.
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Human–Environment Interactions: Microbes, Forests, and Climate

Baquie, Sandra January 2021 (has links)
Antibiotic effectiveness, forests, and climate stability are three of the most endangered public and common goods of the twenty-first century. All three are threatened by individuals ignoring the negative consequences of their actions on society: spreading antibiotic resistance, increasing forest degradation, and accelerating climate change. All these effects are likely to have long-lasting impacts on global health and economic development. This dissertation seeks to understand these human–environment interactions better while evaluating policies promoting sustainable behaviors or improving economic resilience. The first chapter considers the trade-off in prescribing antibiotics: they cure bacterial infections, but they spur antibiotic resistance. I estimate two essential parameters to calibrate any model of antibiotic resistance: the causal impact of prescriptions on antibiotic resistance and the elasticity of demand for an antibiotic. After developing and calibrating a dynamic bio-economic model of the issue, I show that it can be welfare-improving to increase out-of-pocket expenditure on antibiotics used to tackle spreading infections. The second chapter calculates the geographical distribution of people at risk of falling into poverty in the aftermath of droughts and floods in Malawi. Its methods can be expanded to identify the beneficiaries of scalable social safety nets or ex-ante climate insurance. Such programs would increase the resilience of the poor to climate change. The third chapter investigates the potential double dividend of internal migration in terms of poverty alleviation and forest regeneration in Central India. It relies on an innovative index of forest degradation created from high-resolution remote sensing imagery and unique data on internal migration and forest pressure based on a survey of 5,000 households.

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