Submitted by Gabriela Lopes (gmachadolopesufpel@gmail.com) on 2018-02-07T14:11:00Z No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Dissertação Diônvera.pdf: 7391423 bytes, checksum: 33213e2f7d4284eb62de66c2af1c40b0 (MD5) / Approved for entry into archive by Aline Batista (alinehb.ufpel@gmail.com) on 2018-02-08T12:32:56Z (GMT) No. of bitstreams: 2 Dissertação Diônvera.pdf: 7391423 bytes, checksum: 33213e2f7d4284eb62de66c2af1c40b0 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2018-02-08T12:32:56Z (GMT). No. of bitstreams: 2 Dissertação Diônvera.pdf: 7391423 bytes, checksum: 33213e2f7d4284eb62de66c2af1c40b0 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2018-08-22 / O objetivo deste trabalho foi o de avaliar a atividade alelopática de diferentes partes vegetais de Achillea millefolium L. e Cymbopogon citratus (DC) Stapf sobre a germinação e o desenvolvimento inicial de sementes e plântulas de Lactuca sativa L. e Cucumis sativus L. Para a determinação do potencial alelopático das plantas mil-folhas (Achillea millefolium L.) e capim-cidrão (Cymbopogon citratus (DC) Stapf), foram instalados bioensaios em laboratório e em casa de vegetação. Os tratamentos foram extrato aquoso das diferentes partes vegetais de A. millefolium L. e C. citratus L. nas concentrações de 0% (água destilada), 15%, 30%, 45%, 60% e 75%. Foram avaliados germinação, primeira contagem de germinação, índice de velocidade de germinação, comprimento de parte aérea e raiz primária, massa seca total de plântulas, emergência de plântulas, comprimento de parte aérea e de raiz primária e massa seca total das plântulas emergidas. Houve ação alelopática negativa dos extratos de capim-cidrão e das flores de mil-folhas sobre a germinação e desenvolvimento inicial de plântulas de alface em condições de laboratório. Houve afeito alelopático negativo na primeira contagem da germinação, no índice de velocidade de germinação e na germinação em sementes de alface com o uso do extrato de folha milfolhas , em condições de laboratório. Os extratos aquosos de flores, folhas e raiz de mil-folhas apresentaram efeito tóxico para a primeira contagem da germinação de sementes de pepino, sendo que o índice de velocidade da germinação foi mais afetado pelos extratos das flores e folhas de mil folhas, em condições de laboratório. Houve efeito alelopático para o comprimento da parte aérea e massa fresca de plântulas de pepino submetidas aos extratos de flores e folhas de mil-folhas, em condições de laboratório. Houve efeito alelopático significativo no desenvolvimento da raiz das sementes de pepino submetidas aos extratos de folhas de mil-folhas, em condições de laboratório. A primeira contagem da germinação, a germinação, a emergência de plântulas, o comprimento da parte aérea e da raiz de plântulas de alface não foram afetados pelo extrato de raiz de milfolhas, em condições de ambiente protegido. O extrato de capim-cidrão afetou negativamente o índice de velocidade de emergência, a massa fresca e seca de plântulas de alface, em condições de ambiente protegido. O extrato do caule de milfolhas apresentou efeito prejudicial para o comprimento da raiz de plântulas de alface, em condições de ambiente protegido. O extrato de flores de mil-folhas afetou negativamente o comprimento da raiz das plântulas de alface, nas concentrações 15, 30 e 45% e a massa seca em todas as concentrações testadas, em condições de ambiente protegido. / The objective of this work was to evaluate the allelopathic activity of different plant parts of Achillea millefolium L. and Cymbopogon citratus (DC) Stapf on the germination and initial development of seeds and seedlings of Lactuca sativa L. and Cucumis sativus L. (Achillea millefolium L.) and citrus (Cymbopogon citratus (DC) Stapf), bioassays were installed in the laboratory and in greenhouse. The treatments were aqueous extract of the different plant parts of A. millefolium L. and C. citratus L. at the concentrations of 0% (distilled water), 15%, 30%, 45%, 60% and 75%. Germination, first germination count, germination speed index, shoot length and primary root length, total dry mass of seedlings, seedling emergence, shoot length and primary root length, and total dry mass of emerged seedlings were evaluated. There was a negative allelopathic action of extracts of citrus grass and thousand-leaf flowers on germination and initial development of lettuce seedlings under laboratory conditions. There was a negative allelopathic effect on the first germination count, the germination speed index and the germination in lettuce seeds with the use of the 1000 leaf extract under laboratory conditions. The aqueous extracts of flowers, leaves and root of thousand leaves had toxic effect for the first count of the germination of cucumber seeds, and the speed index of the germination was more affected by the extracts of the flowers and leaves of thousand leaves, in conditions. There was allelopathic effect for shoot length and fresh mass of cucumber seedlings submitted to flower extracts and leaves of mille leaves under laboratory conditions. There was a significant allelopathic effect in the development of the root of the cucumber seeds submitted to extracts of leaves of thousand leaves, under laboratory conditions. The first count of germination, germination, seedling emergence, shoot length and root lettuce seedlings were not affected by wild-type root extract under protected environment conditions. The extracts of citrus grass negatively affected the emergence speed index, the fresh and dry mass of lettuce seedlings, under protected environment conditions. The extract of the thousand-leaf stem showed a detrimental effect on the root length of lettuce seedlings under protected environment conditions. Milk leaf extract negatively affected the root length of lettuce seedlings at 15, 30 and 45% concentrations and the dry mass at all concentrations tested under protected environment conditions.

A cachaça é a segunda bebida alcoólica mais consumida no Brasil e vem ganhando espaço no mercado devido aos esforços do setor produtivo e também a ações governamentais. A produção de brasileira de cachaça é estimada em 1,7 bilhão de litros, sendo que cerca de 400 milhões são produzidas em alambiques. A cadeia produtiva não é tecnologicamente homogênea, havendo necessidade do desenvolvimento de tecnologias para aperfeiçoar e controlar a qualidade e a padronização da bebida. O objetivo do trabalho foi avaliar as curvas de volatilização dos principais compostos presentes em aguardente de cana, ao longo de um processo de dupla destilação, realizado em alambique simples, e quantificar a formação e recuperação de compostos voláteis típicos das frações cabeça, coração e cauda do destilado final, utilizando a metodologia da produção de whisky. Foram estudadas as curvas de volatilização dos componentes químicos do destilado ao longo da primeira e da segunda destilação, além da composição química das frações cabeça, coração (aguardente) e cauda produzidas durante o processo, seguindo as metodologias e critérios da legislação vigente no Brasil. Os resultados mostraram que a dupla destilação, baseada na metodologia utilizada para a produção de whisky, proporcionou a melhoria da qualidade química da aguardente de cana-de-açúcar, através da redução nos teores de cobre, acidez volátil, aldeídos e metanol, comparativamente à aguardente testemunha (monodestilada). As curvas de volatilização dos compostos químicos ao longo da destilação da aguardente duplamente destilada mostraram concentrações típicas dos componentes voláteis da fração cabeça (aldeídos, ésteres e metanol) e da fração cauda (acidez volátil e furfural). / The cachaça is the second most consumed beverage in Brazil and it has been gaining market share due to the efforts of the productive sector as well as governmental actions. The production of Brazilian cachaça is estimated at 1.7 billion liters, of which about 400 million are produced in stills. Production chain is not technologically homogeneous and there is need to develop technologies to improve and control the quality and standardization. The objective of this study was to evaluate the volatilization curves of the main compounds present in sugar cane spirits, during a process of double distillation carried out in pot still according the methodology for the production of whisky, and quantify the formation and recovery of volatile fractions of the typical \"head\", \"heart\" and \"tail\" of the final distillate. We studied the curves of volatilization of the chemical components of the distillate along the first and second distillation, and the chemical composition of fractions \"head\", \"heart\" (spirit) and \"tail\" produced during the process, following the methodologies and criteria of the current legislation in Brazil. The results showed that the double distillation, based on the methodology used for the production of whisky, enabled to improve the chemical quality of the sugar cane spirit by reducing the concentrations of copper, volatile acidity, aldehydes and methanol, when compared to the control spirit (single distilled). The volatilization curves of chemical compounds along the distillation of double distilled spirits showed concentrations typical of the volatile fraction of the \"head\" fraction (aldehydes, esters and methanol) and the \"tail\" fraction (volatile acid and furfural).

Beef cattle production is highly criticized because of the high use of land and water resources, and by the pollution (e.g., the gas methane in a cow’s breath and nitrogen in urine) produced by cows fed in feedlots. In contrast to feedlots diets and grasses, some plants (e.g., legumes) contain bioactive compounds (condensed tannins) that reduce pollution and enhance animal nutrition. In my research, I observed that cows grazing a tannin-containing legume (birdsfoot trefoil; BFT) had methane emissions similar to cows fed a feedlot ration with comparable weight gains. Cows in the BFT treatment gained more weight than cows grazing grass (meadow brome) or a legume without tannins (cicer milkvetch). Additionally, I estimated the potential areas in the state of Utah than can sustain birdsfoot trefoil production, with 412,250 ha distributed mostly in the Box elder, Cache, Millard and Sanpete counties. Thus, feeding tannin-containing legumes to cows is a viable alternative to feedlot rations, with greater levels of productivity than other pasture-based systems, which can lead to a more sustainable production of beef.

Calendula officinalis is a useful model crop because calendula flowers are used both ornamentally and medicinally. Organic production systems have many challenges; among these is the synchrony of nitrogen mineralization with the requirements of the crop. Organic greenhouse substrates have significantly different initial nitrogen levels which influence the performance of calendula, the highest initial N and plant performance was found in the organic compost peat substrate (OCP). The addition of supplemental nitrogen improved performance, but only OCP performed as well as the conventionally fertilized peat-based substrate. The nitrogen mineralization patterns in a soil-based greenhouse pot experiment showed that highly processed amendments supplied the highest levels of nitrogen, and that these amendments showed greater vegetative growth when soil was amended with a high-input amendment, but flower production was reduced. There was no observed influence of water stress on nitrogen mineralization, but flowers from water stressed plants had approximately 50% higher concentrations of secondary compounds than non-stressed flowers. Nitrogen mineralization in organic production systems is difficult to predict, but highly influences plant productivity and performance.

A cachaça é a segunda bebida alcoólica mais consumida no Brasil e vem ganhando espaço no mercado devido aos esforços do setor produtivo e também a ações governamentais. A produção de brasileira de cachaça é estimada em 1,7 bilhão de litros, sendo que cerca de 400 milhões são produzidas em alambiques. A cadeia produtiva não é tecnologicamente homogênea, havendo necessidade do desenvolvimento de tecnologias para aperfeiçoar e controlar a qualidade e a padronização da bebida. O objetivo do trabalho foi avaliar as curvas de volatilização dos principais compostos presentes em aguardente de cana, ao longo de um processo de dupla destilação, realizado em alambique simples, e quantificar a formação e recuperação de compostos voláteis típicos das frações cabeça, coração e cauda do destilado final, utilizando a metodologia da produção de whisky. Foram estudadas as curvas de volatilização dos componentes químicos do destilado ao longo da primeira e da segunda destilação, além da composição química das frações cabeça, coração (aguardente) e cauda produzidas durante o processo, seguindo as metodologias e critérios da legislação vigente no Brasil. Os resultados mostraram que a dupla destilação, baseada na metodologia utilizada para a produção de whisky, proporcionou a melhoria da qualidade química da aguardente de cana-de-açúcar, através da redução nos teores de cobre, acidez volátil, aldeídos e metanol, comparativamente à aguardente testemunha (monodestilada). As curvas de volatilização dos compostos químicos ao longo da destilação da aguardente duplamente destilada mostraram concentrações típicas dos componentes voláteis da fração cabeça (aldeídos, ésteres e metanol) e da fração cauda (acidez volátil e furfural). / The cachaça is the second most consumed beverage in Brazil and it has been gaining market share due to the efforts of the productive sector as well as governmental actions. The production of Brazilian cachaça is estimated at 1.7 billion liters, of which about 400 million are produced in stills. Production chain is not technologically homogeneous and there is need to develop technologies to improve and control the quality and standardization. The objective of this study was to evaluate the volatilization curves of the main compounds present in sugar cane spirits, during a process of double distillation carried out in pot still according the methodology for the production of whisky, and quantify the formation and recovery of volatile fractions of the typical \"head\", \"heart\" and \"tail\" of the final distillate. We studied the curves of volatilization of the chemical components of the distillate along the first and second distillation, and the chemical composition of fractions \"head\", \"heart\" (spirit) and \"tail\" produced during the process, following the methodologies and criteria of the current legislation in Brazil. The results showed that the double distillation, based on the methodology used for the production of whisky, enabled to improve the chemical quality of the sugar cane spirit by reducing the concentrations of copper, volatile acidity, aldehydes and methanol, when compared to the control spirit (single distilled). The volatilization curves of chemical compounds along the distillation of double distilled spirits showed concentrations typical of the volatile fraction of the \"head\" fraction (aldehydes, esters and methanol) and the \"tail\" fraction (volatile acid and furfural).

<p>In this thesis, I experimentally investigate feeding selectivity in fallow deer (Dama dama), with respect to plant secondary compounds, especially tannins, which can decrease the quality of foods. I found that fallow deer avoided foods with higher amounts of tannic acid and Quebracho tannin, even though the deer ate some high-tannin food. The food choice was strongly dependent on the context in which the food was presented, so that the food choice in relation to tannin content was relative rather than absolute. When high-tannin food occurred at low frequency, the deer ate proportionally less from this type of food, at least when the difference in tannin content between the two foods was large. A basic implication is that an unpalatable plant type could benefit from its unpalatability, especially when occurring at low frequency. In experiments with two patches, the finding of a stronger within- than between-patch selectivity was mirrored in associational effects. First, low-tannin, palatable food was more eaten when occurring in a high-tannin patch, which corresponds to neighbour contrast susceptibility. Second, high-tannin, unpalatable food in a less defended patch was less eaten, which corresponds to neighbour contrast defence. A proximate cause of the associational effects can be the presence of a simultaneous negative contrast, which was experimentally demonstrated in an additional study. Individual differences in selectivity were present early in life and were consistent over five years, and selectivity was correlated with foraging exploratory behaviour. The results from this thesis suggest that fallow deer are selective in their food choice with respect to tannins from the beginning, and that the frequency of occurrence of different foods, but also the distance between foods and the complexity of presentation, influence the food choice. It is also suggested that a foraging behavioural syndrome is present in mammalian herbivores.</p>

In this thesis, I experimentally investigate feeding selectivity in fallow deer (Dama dama), with respect to plant secondary compounds, especially tannins, which can decrease the quality of foods. I found that fallow deer avoided foods with higher amounts of tannic acid and Quebracho tannin, even though the deer ate some high-tannin food. The food choice was strongly dependent on the context in which the food was presented, so that the food choice in relation to tannin content was relative rather than absolute. When high-tannin food occurred at low frequency, the deer ate proportionally less from this type of food, at least when the difference in tannin content between the two foods was large. A basic implication is that an unpalatable plant type could benefit from its unpalatability, especially when occurring at low frequency. In experiments with two patches, the finding of a stronger within- than between-patch selectivity was mirrored in associational effects. First, low-tannin, palatable food was more eaten when occurring in a high-tannin patch, which corresponds to neighbour contrast susceptibility. Second, high-tannin, unpalatable food in a less defended patch was less eaten, which corresponds to neighbour contrast defence. A proximate cause of the associational effects can be the presence of a simultaneous negative contrast, which was experimentally demonstrated in an additional study. Individual differences in selectivity were present early in life and were consistent over five years, and selectivity was correlated with foraging exploratory behaviour. The results from this thesis suggest that fallow deer are selective in their food choice with respect to tannins from the beginning, and that the frequency of occurrence of different foods, but also the distance between foods and the complexity of presentation, influence the food choice. It is also suggested that a foraging behavioural syndrome is present in mammalian herbivores.

O trabalho realizado constitui uma estratégia em Biotecnologia de Plantas para a investigação dos esquemas bioquímicos controladores da diferenciação celular no processo de enraizamento. Através da técnica da cultura de tecidos \"in vitro\" foram micropropagados clones de Eucalyptus grandis HILL ex MAIDEN (GO 250, GO 682 e GO 669) selecionadas no CEBTEC/USP. Em uma pesquisa preliminar foram estabelecidas e multiplicadas gemas, seguida de testes da composição de meios de cultura para elongação e enraizamento. Foram estudadas diversas possibilidades de balanceamento das substâncias reguladoras de crescimento - ácido indolilbutírico (AIB)/ benzilaminopurina (BAP). Os clones apresentaram comportamentos anatômico-fisiológicos (massa fresca e seca; teor protéico; taxas de multiplicação das brotações epicórmicas, elongação e enraizamento) diferenciados entre si. As frequências de enraizamento mostraram-se superiores às já observadas por outros autores. Foram estabelecidas, ainda, algumas alterações na composição dos meios de cultura empregados. Através de experimentos cinéticos foram determinados os padrões de indução e/ou inibição das enzimas fenilalanina amônia-liase (PAL) e glucose 6-fosfato-desidrogenase (G-6P-DH) importantes para a biossíntese de compostos flavonóides, considerados como os principais cofatores das auxinas endógenas no complexo iniciador do enraizamento. Verificou-se que embora o suprimento exógeno crescente de AIB tenha resultado em maiores taxas de enraizamento, as atividades da PAL e G-6P-DH não se mostraram significativamente alteradas. Contudo, foi observado também que as gemas que enraizaram apresentaram atividade da PAL significativamente superior, evidenciando maior fluxo do Metabolismo do Fenilpropano durante o enraizamento. / This study constitutes a strategy in Plant Biotechnology with the purpose to investigate the regulating biochemical development of the cellular differentiation in the rooting process. Through plant tissue culture \"in vitro\" technique, clones of Eucalyptus grandis Hill ex Maiden (GO 250, GO 682 e GO 669) selected at CEBTEC/USP, were micropropagated. In a preliminary study shoots were multiplied, followed by tests of media culture composition for shoot elongation and root initiation. Several possibilities and rates of plant growth regulators, indolilbutyric acid (IBA)/benzylaminopurine (BAP) were studied. The clones showed different anatomic-physiological behaviours (fresh and oven-dry weight; proteic content; epicormic shoots multiplication rates, elongation and rooting). The frequences of rooting were higher than those described by other authors. Some modifications in the composition of used cuIture media were also defined. Through kinetic experiments, induction and inhibition patterns of phenylalanine ammonia-lyase (PAL) and glucose 6- phosphate-dehydrogenase (G-6P-DH) important to the biossyntesis of flavonoid compounds were determined. They were considered as the main cofactors of endogenous auxins in the root stimulating complex. Although, the increasing exogenous supply of AIB resulted in higher rooting rates, the activities of PAl and G-6P-DH enzyme did not present alterations. However, it was also observed that shoots wich rooted, in the treatments, showed higher PAL activity. resulting in higher flux of phenylpropanoid metabolism during the rooting.

Submitted by Verena Bastos (verena@uefs.br) on 2015-08-04T01:07:09Z No. of bitstreams: 1 TESE_Cleber Miranda Gon?alves_Vers?o Final.pdf: 4396280 bytes, checksum: c384c685c2ef38bd1e840f48280744ee (MD5) / Made available in DSpace on 2015-08-04T01:07:09Z (GMT). No. of bitstreams: 1 TESE_Cleber Miranda Gon?alves_Vers?o Final.pdf: 4396280 bytes, checksum: c384c685c2ef38bd1e840f48280744ee (MD5) Previous issue date: 2015-05-08 / Funda??o de Amparo ? Pesquisa do Estado de S?o Paulo - FAPESP / Cacha?a corresponds to a beverage with characteristic flavor and aroma, constituted mainly of alcohol and water plus some other components formed in small amounts during the process of fermentation, distillation and aging, and known as the secondary products of alcoholic fermentation. The yeasts and fermentation conditions are considered to be the factors that influence the flavor of alcoholic beverages, since the majority of the secondary compounds responsible for the chemical and sensory quality of the beverage are formed during fermentation. The use of selected yeasts for the production of cane spirit has been studied, with a view to increasing productivity, gaining technological advantages and improving the sensory characteristics of the beverage. This study aimed to produce cacha?a in pilot and alembic scales and evaluate the chemical composition of the beverages produced by selected strains of S. cerevisiae; verify the presence of the selected yeast at the end of the fermentation process on a pilot scale and carry out the evaluation of fermentation parameters of the selected strain in relation to commercial and wild inoculums. The following 16 strains of Saccharomyces cerevisiae were tested: SC52, SC60, SC82, SC91, SC102, SC114, SC129, SC138, SC174, SC177, SC179, SC184, SC219, SC220, SC225 and SC229. Among these, only the SC82 strain could pursue multiplication and fermentation scheme steps to produce cacha?a in pilot and alembic scales. By RFLP mtDNA technique was possible to verify the permanence and dominance of selected yeast (SC82) at the end of fermentation process done in pilot scale. In the evaluation of fermentation parameters to S. cerevisiae strain SC82 had a shorter fermentation time (14h average) and a higher yield (48%), greater efficiency (93.94%) and a higher productivity (2.35 g/Lh) at the end of the third fermentation carried out in relation to commercial and wild inoculums. Regarding the results of the chemical analysis of cacha?a produced in pilot and still scale, only the higher alcohol levels were above that allowed by Brazilian legislation in both produced beverages. / A cacha?a corresponde a uma bebida dotada de sabor e aroma caracter?stico, sendo constitu?da principalmente de ?lcool e ?gua e de outros componentes, formados em pequenas quantidades durante o processo de fermenta??o, destila??o e envelhecimento, os quais recebem a denomina??o de produtos secund?rios da fermenta??o alco?lica. As leveduras e as condi??es de fermenta??o s?o apontadas como fatores que influenciam no sabor das bebidas alco?licas, pois a maioria dos compostos secund?rios respons?veis pela qualidade qu?mica e sensorial da bebida ? formada durante a fermenta??o. A utiliza??o de leveduras selecionadas para produ??o de cacha?a apresenta vantagens tecnol?gicas, como permite minimizar contamina??es indesej?veis, reduz o tempo de fermenta??o, aumenta a produtividade e melhora as caracter?sticas qu?micas e sensoriais da bebida. O presente trabalho teve como objetivos produzir cacha?a em escala piloto e de alambique e avaliar a composi??o qu?mica das bebidas produzidas por linhagens selecionadas de S. cerevisiae; verificar a presen?a da levedura selecionada no final do processo fermentativo em escala piloto e realizar a avalia??o de par?metros fermentativos da cepa selecionada em rela??o a in?culos comercial e selvagem. Foram testadas 16 cepas de Saccharomyces cerevisiae: SC52, SC60, SC82, SC91, SC102, SC114, SC129, SC138, SC174, SC177, SC179, SC184, SC219, SC220, SC225 e SC229. Destas, apenas a cepa SC82 conseguiu prosseguir as etapas do esquema de multiplica??o em escala piloto e em escala de alambique, bem como nas etapas do processo de fermenta??o em escala piloto e de alambique e produzir cacha?a. Atrav?s da t?cnica de RFLPmtDNA foi poss?vel verificar a perman?ncia e domin?ncia da levedura selecionada (SC82) no final do processo fermentativo feito em escala piloto. Na avalia??o dos par?metros fermentativos a S. cerevisiae cepa SC82 apresentou um menor tempo de fermenta??o (m?dia de 14 h) e um maior rendimento (48 %), uma maior efici?ncia (93,94 %) e uma produtividade (2,35 g/Lh) superior ao final da terceira fermenta??o realizada em rela??o ao in?culo comercial e ao in?culo selvagem. Em rela??o aos resultados das an?lises qu?micas da cacha?a produzida em escala piloto e da produzida em escala de alambique, apenas os teores de alco?is superiores estavam acima do permitido pela legisla??o brasileira nas duas bebidas produzidas.

Nitrogen (N) deposition has increased globally over the last 150 years and further increase is predicted for the future. Nitrogen is an important nutrient for lichens, involved in many processes in both photobiont and mycobiont.  However, N can be a stressor, causing many lichens and lichen communities to disappear with increased deposition. The objective of this thesis was to investigate the response of epiphytic lichens to increased N load. This was done by simulating an increased N deposition to lichens in a boreal forest with low background N, including both short term studies with transplanted lichens and long term studies of naturally established lichens. Alectoria sarmentosa was used as a model species for a N-sensitive lichens and Platismatia glauca as a relatively more N-tolerant lichen. Nitrogen deposition was simulated by daily spraying during the growing season with water and isotopically labeled ammonium nitrate (NH4NO3). In Paper I, I found that when N is supplied in realistic doses (equivalent to deposition of 0.6, 6, 12.5, 25 and 50 kg N ha-1), there were no significant differences in uptake of NO3- or NH4+ in either of the lichen species. The results in Paper II indicate that A. samentosa may be limited by phosphorous (P) and not N limited as expected. That study highlights the importance of P, when studying the effects of N deposition, since P can both mitigate and intensify the negative effects of N on epiphytic lichens. Paper III shows that four years of simulated N deposition caused an alteration of the epiphytic lichen community, since A. sarmentosa decreased in the highest N loads (25 and 50 kg ha-1 year-1), Bryoria spp. decreased to 12.5 kg N and higher loads and Hypogymnia physodes decreased over time for all treatments except in 12.5 kg ha-1, where it only decreased during the first treatment year and then increased after 2007.  The abundance of Platismatia glauca increased over time, independent of treatment. As hypothesized, responses to the treatments differed among species, reflecting their different N optima. In paper IV, the effects of N on carbon-based secondary compounds were studied. None of the studied species (P. glauca, A. sarmentosa, Lobaria scrobiculata and Xanthoria aureola) reduced their concentration of secondary compounds during the experimental period, but in P. glauca the concentration of all compounds were significantly lower in N treated thalli compared with control thalli. The results are consistent with a high degree of constitutive defence in three of the four studied lichens, and we conclude that all four studied lichens seem to have a robust chemical defence system despite considerable manipulation of the environmental conditions. However, we don't know if these lichens are able to keep up the high protection level over longer periods comprising a number of years when more new tissue is formed. In conclusion, long term experiments are necessary to understand lichen response to environmental changes.