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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.
81

Efeito do fornecimento de silagens de milho com alta ou baixa digestibilidade da fibra sobre o ganho de peso e consumo de novilhas em crescimento / Effect of feeding growing heifers with corn silages with high or low fiber digestibility on intake, body gain

Bárbara Santos Marques 25 January 2013 (has links)
Objetivou-se avaliar o efeito da digestibilidade da fibra do milho sobre o consumo, ganho de peso e composição da carcaça de novilhas Nelore em crescimento, de modo a validar este índice como indicador da qualidade nutricional de híbridos de milho em programas de melhoramento genético e de seleção de híbridos para silagem. Foram plantados quatro híbridos de milho com diferente digestibilidade da fibra, IAC 8390, 30F90Y, 30S40Y e DKB 390Y, sendo a digestibilidade da FDN da dieta determinada após incubação de 30 horas. Os milhos foram colhidos aos 62, 82 e 104 dias crescimento, para determinar principalmente a digestibilidade da folha e do colmo dos híbridos, para determinar quais híbridos fariam parte da dieta experimental. Foram utilizadas quarenta e oito novilhas da raça Nelore com aproximadamente 250 kg, confinadas por 63 dias, em delineamento de bloco casualizados, em grupo de 3 novilhas por baia, de acordo com o peso vivo inicial. A cada 21 dias, os animais eram pesados, sendo a avaliação da carcaça feita no início do período A dieta experimental foi constituída de quatro rações, com relação volumoso/concentrado de 20:80 e 40:60, com volumoso de duas silagens de milho, 30F90Y, de alta digestibilidade da FDN e, 30S40Y, de baixa digestibilidade da FDN. Foi analisado o tamanho de partícula de amostras da dieta e das sobras/baia pela peneira Penn State Forage Particle. Houve diferença na digestibilidade da FDN dos híbridos na fração colmo, entre os dias de coleta, sendo que a digestibilidade in vitro da matéria seca (DIVMS) reduziu após o período de florescimento dos híbridos e houve uma variação entre os híbridos, em cada coleta. A digestibilidade in vitro da fibra em detergente neutro (DIVFDN), também reduziu com a maturidade da planta, porém houve uma diferença entre os híbridos apenas na coleta aos 82 dias de crescimento. O híbrido 30F90Y foi superior aos demais ao analisar a DIVMS e DIVFDN. Houve diferença entre o tamanho de partículas da dieta oferecida e o tamanho de partícula que restou na sobras, sendo que houve efeito de seleção apenas para a dieta com 40% de concetrado. Houve interação milho*dieta tanto para consumo de matéria seca (CMS) quanto para consumo da fibra em detergente neutro (CFDN), sendo que o híbrido 30F90Y, de maior digestibilidade, teve consumo maior, inclusive na dieta com 20% de concentrado. Para desempenho, foi observado efeito da dieta no ganho médio diário (GMD), sendo maior o ganho de peso (GP) na dieta com a silagem do híbrido 30F90Y Já a conversão alimentar e a composição de carcaça não tiveram efeito de dieta, híbrido de milho ou interação dieta*milho. A utilização de híbridos com melhor digestibilidade da fibra, é uma indicador de híbr do destinado a nutrição animal, pois alterou o consumo, o ganho de peso, porém não alterou a conversão alimentar e composição de carcaça. / The objective of this study was to evaluate the effect of fiber digestibility on intake, weight gain and carcass of growing Nellore heifers, aiming to validate this rate as an indicator of nutritional quality on corn hybrids in programs of genetical improvement and selection of hybrids for silage. Four corn hybrids on different fiber digestibility were raised, IAC 8390, 30F90Y, 30S40Y and DKB 390Y, being the FDN digestibility determined on the diet after a 30-hour-incubation period. The harvest was at the 62, 82 and 104 growing days to mainly determine the leaf and stem digestibility in hybrids to identify which ones would be part of the experimental diet. Forty-eight Nellore heifers of approximately 250 kg BW were housed for 63 days, in randomized blocks, in groups of three heifers per pen, according to its initial body weight. Each 21 days the animals were weighed and the carcass evaluation was done in the beginning of the period. The experimental diet was composed of four rations at 20:80 and 40:60 of roughage/concentrate respectively, in which the corn silage was used the 30F90Y, the one with high digestibility in FDN, and the 30S40Y, of low digestibility in FDN. The particle size of samples collected from the diets and ortis of each pens were analyzed by the Penn State Forage Particle sieve. There was difference in the FDN digestibility for hybrids in the stem fraction among the collection days, being the dry matter digestibility in vitro (DIVMS) reduced after the hybrid blossom and there was a variancy among the hybrids, in each collection. The digestibility in vitro of fiber detergente neuter (DIVFDN), was also reduced according to tha plant maturity, however there was a difference among the hybrids only in the collection at the 82 day of growth. The hybrid 30F90Y was superior to the other when analyzed the DIVMS and DIVFDN. There was difference between the particle size on the diets and the particle size on the ortis, with a selection affect only for the diet at 40% concentrate. There was interaction on the corn*diet for the dry matter intake (CMS) and for the fiber detergent neuter intake (CFDN), beingt the hybrid 30F90Y of higher digestibility, intake, and also on the diet with 20% concentrate. For performance was observed the diet effect on the average in daily weight gain (GMD), in which the highest weight gain (GP) was obtained on the silage of the hybrid 30F90Y. The feed conversion and carcass had no diet effect, neither corn hybrid nor interaction diet*corn. The hybrids with higher fiber digestibility is an indicator for its usage in animal nutrition once they altered the intake and the weight gain, although it hasn\'t altered the feed conversion and the carcas.
82

Crescimento da planta e rendimento de sementes de feijão-caupi em Bom Jesus da Lapa - BA / Plant growth and yield of cowpea seeds in Bom Jesus da Lapa - BA

Vieira, Leylla Neves 01 June 2015 (has links)
Submitted by Maria Beatriz Vieira (mbeatriz.vieira@gmail.com) on 2017-03-16T16:20:17Z No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) dissertacao_leylla_neves_vieira.pdf: 674559 bytes, checksum: df010b0c5efd26b89b26f75cd54dab6c (MD5) / Approved for entry into archive by Aline Batista (alinehb.ufpel@gmail.com) on 2017-03-17T22:20:19Z (GMT) No. of bitstreams: 2 dissertacao_leylla_neves_vieira.pdf: 674559 bytes, checksum: df010b0c5efd26b89b26f75cd54dab6c (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Approved for entry into archive by Aline Batista (alinehb.ufpel@gmail.com) on 2017-03-17T22:21:27Z (GMT) No. of bitstreams: 2 dissertacao_leylla_neves_vieira.pdf: 674559 bytes, checksum: df010b0c5efd26b89b26f75cd54dab6c (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2017-03-17T22:21:38Z (GMT). No. of bitstreams: 2 dissertacao_leylla_neves_vieira.pdf: 674559 bytes, checksum: df010b0c5efd26b89b26f75cd54dab6c (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2015-06-01 / Sem bolsa / O uso de sementes de qualidade na região de Bom Jesus da Lapa é fundamental para o sucesso da lavoura. O objetivo desse trabalho foi avaliar o crescimento e o rendimento de quatro cultivares de feijão caupi (Vigna unguiculata (L.) Walp.) em Bom Jesus da Lapa - BA. Foram determinadas a razão de massa foliar, a matéria seca de folhas e total, a massa de 100 sementes, índice de colheita e o rendimento de sementes para as cultivares Pajeú, Guariba, Rouxinol e variedade local. O delineamento experimental foi de blocos ao acaso com quatro cultivares e cinco blocos. O crescimento das plantas e o rendimento de sementes de genótipos de feijão-caupi mostra desempenho distinto para a condição de Bom Jesus da Lapa - BA. Os genótipos Rouxinol e Pajeú apresentam similar crescimento com superioridade em relação aos genótipos Guariba e Local. O genótipo Guariba apresenta rendimento superior ao Rouxinol, Pajeú e Local. Para os quatro genótipos observa-se forte correlação entre o índice de colheita e o rendimento de sementes. / The use of quality seeds in the region of Bom Jesus da Lapa is critical to the success of the crop. The aim of this study was to evaluate the growth and yield of four cowpea (Vigna unguiculata (L.) Walp.) In Bom Jesus da Lapa - BA. They determined the ratio of leaf mass, the leaves dry matter and total mass of 100 seeds, harvest index and seed yield for Pajeú cultivars Guariba, Nightingale and local variety. The experimental design was randomized blocks with four cultivars and five blocks. Plant growth and yield of cowpea genotypes seeds shows distinct performance for the condition of Bom Jesus da Lapa - BA. The Nightingale and Pajeú genotypes had similar growth with superiority over genotypes Guariba and location. The Guariba genotype has income above the Nightingale, Pajeú and location. For the four genotypes there is strong correlation between harvest index and seed yield.
83

Desempenho de sementes de feijão tratadas com biotivador / Performance of bean seeds treated with bioactivator

Carvalho, Lara Sulamita Modesto Jacó de 30 May 2012 (has links)
Made available in DSpace on 2014-08-20T13:44:29Z (GMT). No. of bitstreams: 1 dissertacao_lara_jaco_de_carvalho.pdf: 1163132 bytes, checksum: 6026bdccb3704daf5e933504e09bf2e8 (MD5) Previous issue date: 2012-05-30 / The bean (Phaseolus vulgaris L.) is grown in all regionsof Brazil andis characterized asanimportant sourceof protein in food, especially forlow-income population, also serving as a source of iron, and carbohydrates. Bioactivators are complex organic substances that can alter the plant growth. Among bioactivators, the commercial producer HX® activates several physiological responses such as the expression of proteins. The objective of this study was to evaluate the physiological quality of common bean seeds treated with a bioactivator. Seeds of bean cultivar Perola. The seeds were first disinfected and then be treated with an equivalent dose of 5 ml per kg seeds were sown in plastic pots with a capacity of 280 mL. And gauged by the following tests: germination, height, and weight ofthe plant.Based on these resultswe conclude that: the biativador HX® promotes increase in the height of bean plants to seven days after sowing, the dry matter of root, shoot and to tal be an plants is greatest between 14 and 28 days after sowing when the seeds are treated with bioactivator HX®. / O feijão (Phaseolus vulgaris L.) é cultivado em todas as regiões do Brasil e caracterizando-se como uma importante fonte de proteína na alimentação, em especial para a população de baixa renda, servindo também como fonte de ferro, e carboidratos. Bioativadores são substâncias orgânicas complexas modificadoras do crescimento vegetal. Dentre os compostos que possuem efeito bioativador, o produtor comercial HX® ativa várias reações fisiológicas, como a expressão de proteínas. O objetivo neste trabalho foi avaliar a qualidade fisiológica de sementes de feijão tratadas com um bioativador. Foram utilizadas sementes de feijão cultivar Pérola. As sementes foram inicialmente desinfetadas para então serem tratadas com uma dose equivalente a 5 mL por kg. As sementes foram semeadas em tubetes com capacidade de 280 mL. E avaliados pelos seguintes testes: teste de germinação, altura, e peso de planta. Com base nos resultados é possível concluir que: o biativador HX® promove aumento na altura de plantas de feijão aos sete dias após a semeadura; a matéria seca da raiz, parte aérea e total em plantas de feijão entre 14 e 28 dias após a semeadura é maior quando as sementes são tratadas com bioativador HX®.
84

DEJETO LÍQUIDO DE SUÍNOS E MANEJOS DE SOLO NA SUCESSÃO AVEIA/MILHO/TRIGO DUPLO PROPÓSITO/SOJA / PIG SLURRY AND SOIL MANAGEMENTS IN SUCCESSION OF OAT/CORN AND DUAL PURPOSE WHEAT/SOYBEAN

Fabbris, Cristiano 07 June 2013 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Swine production in southern Brazil is concentrated on small farms, seeking the recovery of waste as a source of nutrients crops of economic interest. The interaction between applications of pig slurry and soil management is common on small farms, however scarce information was found about the main responses of agricultural crops under this condition. Thus, the present work aimed to evaluate the use of pig slurry, associated with soil management in succession oat / maize and double purpose wheat / soybean. The experimental design was a factorial in a randomized complete block design, with four replications. The treatments consisted of doses of pig slurry (without manure, 20, 40, 80 m3 ha-1), and mineral fertilizer in three different soil management: no tillage, chiseling and chiseling + disking. The application of pig slurry was held before oat/maize and wheat crops sowing, and the soil management employed only before the establishment of winter crops. The application of pig slurry in succession oat / maize showed increases in dry matter yield, and in the accumulation of nitrogen, phosphorus and potassium, and in the grain yield. As for soil management, no-tillage favored the production of oat dry matter yield and soybean grain yield. However, the dual-purpose wheat proved to be low responsive to soil management employed. As for maize, the interaction between higher doses of pig slurry and with tillage managements promotes increases in grain yield. The application of pig slurry before the dual purpose wheat sowing promoted increases in dry matter production and grain yield. The residual effect of five applications of pig slurry does not alter the soybean grain yield. / A produção de suínos no Sul do Brasil concentra-se em pequenas propriedades rurais, que buscam o aproveitamento dos resíduos como fonte de nutrientes as culturas agrícolas de interesse econômico. Aplicação de dejeto líquido de suínos e manejos de solo diferenciados é comum em pequenas propriedades rurais, no entanto são escassas informações sob as repostas das principais culturas agrícolas frente a esta condição. Nesse sentido, o trabalho teve por objetivo avaliar a influência do uso de dejeto líquido de suínos, associado a manejos de solo na sucessão aveia/milho e trigo duplo propósito/soja. O delineamento experimental foi de blocos ao acaso em esquema fatorial, com quatro repetições. Os tratamentos constaram da interação de doses de dejeto líquido de suínos (sem dejeto, 20, 40, 80 m3 ha-1), e adubação mineral, em três diferentes manejos de solo: plantio direto, escarificado e escarificação + gradagem. A aplicação do dejeto líquido de suínos foi realizada antes da semeadura das culturas aveia, milho e trigo, os manejos de solo realizados antes do estabelecimento das culturas de inverno. A aplicação de dejeto líquido de suínos na sucessão aveia/milho promoveu incrementos na produção de matéria seca, no acúmulo de nitrogênio, fósforo e potássio, e na produtividade de grãos. Quanto aos manejos de solo, o plantio direto favoreceu a produção de matéria seca da aveia e a produtividade de grãos de soja. Já para o milho, a interação entre maiores doses de dejeto líquido de suínos e manejos com revolvimento do solo promove incrementos na produtividade de grãos. A aplicação do dejeto líquido de suínos antes da semeadura do trigo duplo propósito promove incrementos na produção de matéria seca e na produtividade de grãos. O efeito residual de cinco aplicações de dejeto líquido de suínos não altera a produtividade de grãos de soja.
85

Produção de forragem e de sementes de Brachiaria decumbens Stapf em função da adubação com nitrogênio e fósforo e cultura antecessora /

Oliveira, Simone Aparecida de. January 2002 (has links)
Orientador: Marco Eustáquio de Sá / Banca: João Nakagawa / Banca: Edson Lazarini / Resumo: Neste trabalho, estudou-se o efeito da adubação com nitrogênio e fósforo e da sucessão de culturas como forma para o aumento da produção e qualidade de sementes e forragem em Brachiaria decumbens. Para tanto, foi instalado um experimento na Fazenda de Ensino e Pesquisa da FE/ UNESP - Câmpus de Ilha Solteira, localizada em Selvíria - MS, utilizando-se as culturas do milheto, do sorgo granífero, do guandu anão, do nabo forrageiro e o pousio, antes da implantação da Brachiaria decumbens. As quatro culturas foram implantadas em maio de 2000, e posteriormente (após a retirada destas culturas) foi implantada a cultura da Brachiaria decumbens. Foram utilizados três níveis de adubação fosfatada (0, 1- dose recomendada pelo Boletim 100 e 2- o dobro da recomendada) e dois níveis de adubação nitrogenada (0- sem e 1- 40 kg ha-1). Foram realizadas avaliações de: matéria seca das plantas, teor de macronutrientes (N, P, K, Ca, Mg e S) e produção de grãos para as culturas de guandu anão, milheto, nabo forrageiro, pousio e sorgo granífero; matéria seca das plantas, produção de sementes, análise de pureza física, teste de germinação e teste de tetrazólio para Brachiaria. O delineamento experimental utilizado foi blocos casualizados com parcelas sub sub divididas totalizando 30 tratamentos e 6 repetições, obtidos da combinação entre culturas (4) + pousio (tratamentos principais) e como subparcela: níveis de fósforo (3) x níveis de nitrogênio (com e sem N) perfazendo 30 tratamentos. O milheto apresentou a maior produção de matéria seca (5.977 kg ha-1) e o sorgo granífero a melhor produção de grãos (3.388 kg ha-1), sendo que os melhores teores nutricionais ocorreram no guandu anão e nabo forrageiro. A melhor produção de sementes de Brachiaria decumbens foi encontrada para incorporação de nabo forrageiro associado com doses recomendadas... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: In this work, it was studied the effect of the manuring with nitrogen and match and of the crop's succession the form goes the increase in production and quality of seeds and goes into hiding in Brachiaria decumbens. For so much, an experiment was installed in Experimental Station of Faculdade de Engenharia de Ilha Solteira / UNESP, located in Selvíria (MS), being used the of the pear millet, of the sorghum, of the dwarfish pigeon pea, of the turnip forage and the fallow area, before the implantation of the Brachiaria decumbens. The four crops were implanted in May of 2000, and later (after the retreat of these crops) the Brachiaria decumbens crop was implanted. Three levels of phosphate fertilization were used (0, 1 - dose recommended by the Bulletin 100 and 2 - the double of the recommended) and two levels of fertilization nitrogen (0 - without and 1 - 40 kg have-1). Evaluations were accomplished of: matter dries of the plants, macronutrients content (N, P, K, Ca, Mg and S) and grains yield for the crops of dwarfish pigeon pea, millt, turnip forage, fallow area and sorghum; matter dries of the plants, seed yield, physical purity, germination and seed viability for Brachiaria. The used experimental design was randomized blocks with parcels sub sub divided totaling 30 treatments and 6 repetitions, obtained of the combination among crops (4) + fallow area (main treatments) and as subplot: match levels (3) x levels of nitrogen (with and without N) totaling 30 treatments. The millet presented the largest production of dry matter (5.977 kg ha-1) and the sorghum the best grains yield (3.388 kg ha-1), and the best nutritional content happened in the dwarfish pigeon pea and turnip forage. The best yield seed was observed in the sucession of Brachiaria crop with forage turnip, utilizing doses of 40 kg of nitrogen ha-1 and 20 kg of phosphorus ha-1... (Complete abstract, click electronic address below) / Mestre
86

Evaluation of Harvesting, Densification, and Storage Practices of Corn Stover for Bioenergy Feedstock Production

Billman, Ryan January 2014 (has links)
No description available.
87

EFFECT OF GUT PEPTIDES ON HYPOTHALAMIC mRNA CONCENTRATION AND DRY MATTER INTAKE IN RUMINANTS

Relling, Alejandro Enrique 22 July 2009 (has links)
No description available.
88

Growth and development of baby spinach (Spinacia oleracea L.) with reference to mineral nutrition

Nemadodzi, Lufuno Ethel 01 June 2015 (has links)
Baby spinach is a relatively new crop in South Africa with both commercial significance and reputed health benefits. It is known to assist in combating degenerative conditions associated with ageing, such as heart disease, cardiovascular disease, Alzheimer’s disease, cataracts and several forms of cancer. Three parallel NPK trials were conducted to investigate the effects of nitrogen (N), phosphorus (P) and potassium (K) on the growth and development of baby spinach. N and P treatments were arranged as (0, 45, 75, 105, 120 kg.ha -1 N and P), and K treatments were arranged as (0, 63, 85, 127, 148 kg.ha -1) in a randomised complete block designed with four replicates. Results showed that yield, dry matter, chlorophyll content and Leaf Area Index (LAI) were significantly increased by increasing the N application, while K had a significant effect on the LAI but not on yield, dry matter, chlorophyll content or stomatal conductance. Nitrogen treatments quadrupled fresh yield, dry matter and chlorophyll content, reaching maximum impact at 75 kg.ha-1 N. Phosphorus application showed significantly increased yields, dry matter and chlorophyll content, reaching maximum impact at 75 kg.ha-1 P. Therefore, to achieve optimum growth with N and P, 75 kg.ha-1 is recommended. The optimum rates of N, P and K were then used to formulate a NPK combined trial which was arranged as 0, 30:30:40, 45:45:60, 60:60:70, 75:75:90 kg.ha-1 in a randomised complete block design with three replicates. The results showed that maximum impact on yield, chlorophyll content, fresh and dry matter was achieved when combined NPK was applied at 45:45:60 / Agriculture and  Animal Health / M. Sc. (Agriculture)
89

Evaluation of selected sweetpotato (Ipomoea batatas) accessions for drought tolerance

Omotobora, Babajide Olusegun 06 1900 (has links)
Sweetpotato (Ipomoea batatas) is a major staple food in Africa and the rest of the world where they are discovered to be a good source of carbohydrates, vitamin A, vitamin C and protein. The maximum production potential of the crop is being hampered by severe drought which ravages most parts of Africa. The main aim of this project therefore is to screen collected accessions of sweetpotatofor drought tolerance in a quick screening method with a view to identify cultivars that can perform well under water stress conditions. Fifty selected sweetpotato accessions consisting of cultivars and breeding lines collected from the ARC-VOPI gene bank were planted for drought screening in the glass house for 6 weeks during which water was withheld to induce stress. Observations were made on number of dead plants and days to wilting point, the results were analyzed and 12 best performing cultivars were selected for field trials. The field trial was carried out in Lwamondo, Thohoyandou for 6months under rain-fed conditions. The experiment was conducted in a complete randomized block design with 6 replicates.Yield data and growth parameters were collected every 8 weeks during the trial period and the data collected was analyzed using ANOVA. The best performing cultivars were Zapallo, Tacna, Ejumula, 2004-9-2 and Ndou. They were therefore recommended for further evaluation in other drought prone areas of the country. / Agriculture and  Animal Health / M. Sc. (Agriculture)
90

Stem hydraulic architecture and xylem vulnerability to cavitation for miombo woodlands canopy tree species

Vinya, Royd January 2010 (has links)
Africa's miombo woodlands constitute one of the most important dry tropical forests on earth, yet the hydraulic function of these woodlands remains poorly researched. Given the current predictions of increased aridity by the end of this century in the miombo ecoregion, understanding the likely response of miombo woodlands tree species to water stress is crucial in planning adaptation strategies. Predicting the response of miombo woodlands to future climate trends is hampered by a lack of knowledge on the physiology of the common miombo woodlands tree species. In particular, plant-water relations for this woodlands type are not well understood. An understanding of plant-water relations for this woodlands type will provide insights into how water limits tree species distribution in this ecosystem. This will also improve our prediction model on the likely response of this ecosystem to predicted climate change. For this reason, the overall objective of this research was to evaluate the hydraulic architecture and xylem vulnerability to cavitation for nine principal miombo woodlands tree species differing in drought tolerance ability and habitat preference. This was achieved by; examining the hydraulic properties and evaluating the extent to which each hydraulic design was vulnerable to water stress-induced xylem cavitation; investigating how seasonal changes in plant-water relations influences seasonal patterns of leaf display and; analyzing the relationship between stem hydraulic supply and leaf functional traits related to drought tolerance ability. This research has found that drought-intolerant tree species with mesic specialization have more efficient stem hydraulic systems than co-occurring habitat broad ranging species. Broad ranging tree species attain wider habitat distribution by adjusting their hydraulic supply in response to changing ecosystem water availability. The finding that hydraulic properties differ significantly between tree species with contrasting habitat preference suggests that tree hydraulic design may have some adaptive ecological role in influencing species habitat preferences in miombo woodlands. The evaluation of xylem vulnerability to cavitation revealed that mesic specialized tree species were more vulnerable to water stress-induced cavitation than habitat broad ranging tree species. Vulnerability to cavitation in individuals from the same broad-ranging species growing in contrasting habitats showed only marginal and statistically insignificant (P > 0.05) differences between wet and dry sites. In the investigation of the influence of seasonal changes in stem water relations on seasonal leaf display, seasonal rhythms in stem water status were found to exert significant controls on leaf phenology. Mesic specialists had strong stem water controls throughout the year in comparison to broad ranging tree species. An analysis of the relationship between stem hydraulic supply and leaf functional traits suggests that stem hydraulic supply constrains leaf biomass allocation patterns among miombo tree species. Mesic specialists tend to invest more in leaf longevity than broad ranging tree species. This thesis has uncovered some interesting relationships between plant-water-relations and the distribution of miombo woodlands tree species. These results lead to the conclusion that in an event of increased ecosystem drying under future climate trends, tree species with mesic specialisation are at a greater risk of experiencing cavitation related species mortality than broad ranging ones.

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