Submitted by HERMANO JOSÉ RIBEIRO HENRIQUES (hermano.henriques.hh@gmail.com) on 2018-04-19T02:51:02Z No. of bitstreams: 1 Dissertação Hermano 23-03-18 FINAL.pdf: 675802 bytes, checksum: 998790963004d6f800e75626d999e4c9 (MD5) / Approved for entry into archive by Cristina Alexandra de Godoy null (cristina@adm.feis.unesp.br) on 2018-04-20T16:48:25Z (GMT) No. of bitstreams: 1 henriques_hjr_me_ilha.pdf: 457543 bytes, checksum: ccd8449717ed932372ce579f36b5f1fb (MD5) / Made available in DSpace on 2018-04-20T16:48:25Z (GMT). No. of bitstreams: 1 henriques_hjr_me_ilha.pdf: 457543 bytes, checksum: ccd8449717ed932372ce579f36b5f1fb (MD5) Previous issue date: 2018-02-20 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / A utilização das regiões de cerrado para a produção agrícola se estabeleceu inicialmente pelo uso intensivo do solo proporcionando alterações nos atributos físicos, químicos e biológicos de acordo com o tipo de manejo adotado. O experimento foi realizado na Fazenda de Ensino, Pesquisa e Ensino (FEPE-Cerrado), pertencente à Faculdade de Engenharia de Ilha Solteira, no município de Selvíria- MS, em um LATOSSOLO VERMELHO Distroférrico, de textura argilosa (EMBRAPA, 2013), nos anos de 2016 a 2017 teve como objetivo de comparar os sistemas de manejo do solo a ser adotada em safras seguidas para estabilização do plantio direto (SPD) nas culturas de soja (verão) e do sorgo (outono-inverno). O delineamento experimental foi de blocos ao acaso, com quatro repetições e sete tratamentos: sistema de semeadura direta contínuo (de 23 e 24 anos de implantação), sendo que cultivo mínimo, preparo convencional do solo com grade pesada e arado de aiveca seguida de três gradagens leves e plantio direto sobre cada destes manejos do solo realizados continuamente com o mesmo número de safras seguidas até a 7° e 8° safra. Para comparação de medias foram avaliados os dados biométricos das culturas da soja e do sorgo, atributos físicos do solo e quantidade de carbono orgânico total. Os resultados obtidos indicaram que os sistemas de semeadura direta contínuo apresentaram maior quantidade de estoque de carbono orgânico total. A elevação da produtividade de grãos de soja está diretamente relacionada à maior presença de plantas no estande final quando o solo foi preparado com grade pesada seguida do tempo de implantação como sistema plantio direto, diferentemente dos manejos de preparo do solo com grade pesada e arado de aiveca contínuo terem menor sobrevivência de plantas, refletiu diretamente na queda de produtividades de grãos de soja em razão do maior campo de visão ter facilitado o ataque de pássaros. Os mesmos tratamentos de manejos do solo adotados na cultura do sorgo apresentaram efeito nulo sobre características biométricas, demostrando que independentemente do tempo de implantação do SPD e manejo do solo adotado anteriormente continua sendo a opção mais viável economicamente para a região de Cerrado. / The use of cerrado regions for agricultural production was established initially with intensive use of the soil, providing changes in the physical, chemical and biological attributes according to the type of management adopted. The experiment was carried out at the Fazenda de Ensino, Pesquisa e Ensino (FEPE-Cerrado), belonging to the Faculty of Engineering of Ilha Solteira, in the of Selvíria-MS, in an Oxisol (EMBRAPA, 2013), year period from 2016 to 2017, had the objective of comparing the soil tillage systems to be adopted in crop seasons for stabilization of no-tillage (SPD) in soybean (summer) and sorghum (autumn-winter). The experimental design was a randomized block design, using factorial arrangement with four replications and seven treatments: continuous no-tillage (23 and 24 years of implantation), with minimum tillage, conventional soil tillage with heavy grating, and shisel moldboard pow by three disk plowing followed and no-tillage on each of these soils managed continuously with the same number of harvests followed up to the 7th and 8th harvests. Biometric data from soybean and sorghum cultures, soil physical attributes and amount of total organic carbon were evaluated for comparison of means. The results showed that continuous direct seeding systems presented higher amounts of total organic carbon stock. The increase of soybean grain yield is directly related to the greater presence of plants in the final stand when the soil was prepared with heavy grating followed by the time of implantation as no-tillage system, unlike the soil preparation operations with heavy grating and shisel moldboard pow continued to have lower plant survival, directly reflected in the fall in yields of soybeans because the greater field of view facilitated the attack of birds. The same soil management treatments adopted in the sorghum crop showed zero effect on biometric characteristics, showing that regardless of the time of SPD implementation and previously adopted soil management, it remains the most economically viable option in the Cerrado.

Abstract: Certain cultures present especification in the assimilation of some ions, that are or not in available ways in the soil. The minerals have fundamental paper in the presence of those elements that, a lot of times, they are together originating from of the processes of meteorization of the rocks with the decomposition of the organic matter. This work had for objective to study the extraction and/or solubilization of some present chemical elements in the studied minerals and in a red latosoil, for the action of some organic acids produced starting from the decomposition of the matter ligno-cellulousic, through the microbial action, hoping to contribute in some way in the understanding of the mechanisms of fertility of the soil and, consequently, in the mineral nutrition of plants. The used minerals were: manganite [MnO(OH)], hematite (Fe2O3), pirolusite (MnO2), caolinite [Al2Si2O5(OH)4], goethite (HFeO2), bentonite [Na3(Al,Mg)2 2(Si4O10)(OH)2.H2O] e magnetite(Fe3O4), that commonly happen in areas humid intertropicals and a red latosoil, of sandy texture that, it represents more that 20% of the area of the State of Saint Paulo. The minerals and LV were triturated and drizzled in 0,05mm mesh, separately. After having examined with relationship your structure for Difratometric of Ray-X (XRD), 1g of those minerals and LV were conditioned, separately, in glass flasks. Some samples were only treated with distilled water and other with solution 0,02 mol.L-1 of the following acids: acetic, butyric, citric, carbolic, lactic, malic, oxalic, propionic and tannic, separately, for 53 days, with weekly agitations and conditions aerobics. After the digestion of the samples, they were certain the litio concentrations, sodium, potassium, magnesium, calcium, barium, vanadium, cromium, molibdenium, manganese, iron, cobalt, nickel, copper, zinc, cadmium, mercury, boron, aluminum, silicio, tin, lead, match... (Complete abstract click electronic access below) / Orientador: Ademércio Antonio Paccola / Coorientador: Pedro de Magalhães Padilha / Banca: Silas Macedo Silva / Banca: Paulo Sergio R. de Oliveira / Banca: Antonio Francisco Godinho / Banca: Rosana Cavalcante dos Santos / Doutor

Orientador: Élcio Hiroyoshi Yano / Resumo: A utilização das regiões de cerrado para a produção agrícola se estabeleceu inicialmente pelo uso intensivo do solo proporcionando alterações nos atributos físicos, químicos e biológicos de acordo com o tipo de manejo adotado. O experimento foi realizado na Fazenda de Ensino, Pesquisa e Ensino (FEPE-Cerrado), pertencente à Faculdade de Engenharia de Ilha Solteira, no município de Selvíria- MS, em um LATOSSOLO VERMELHO Distroférrico, de textura argilosa (EMBRAPA, 2013), nos anos de 2016 a 2017 teve como objetivo de comparar os sistemas de manejo do solo a ser adotada em safras seguidas para estabilização do plantio direto (SPD) nas culturas de soja (verão) e do sorgo (outono-inverno). O delineamento experimental foi de blocos ao acaso, com quatro repetições e sete tratamentos: sistema de semeadura direta contínuo (de 23 e 24 anos de implantação), sendo que cultivo mínimo, preparo convencional do solo com grade pesada e arado de aiveca seguida de três gradagens leves e plantio direto sobre cada destes manejos do solo realizados continuamente com o mesmo número de safras seguidas até a 7° e 8° safra. Para comparação de medias foram avaliados os dados biométricos das culturas da soja e do sorgo, atributos físicos do solo e quantidade de carbono orgânico total. Os resultados obtidos indicaram que os sistemas de semeadura direta contínuo apresentaram maior quantidade de estoque de carbono orgânico total. A elevação da produtividade de grãos de soja está diretamente relacionada à ma... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The use of cerrado regions for agricultural production was established initially with intensive use of the soil, providing changes in the physical, chemical and biological attributes according to the type of management adopted. The experiment was carried out at the Fazenda de Ensino, Pesquisa e Ensino (FEPE-Cerrado), belonging to the Faculty of Engineering of Ilha Solteira, in the of Selvíria-MS, in an Oxisol (EMBRAPA, 2013), year period from 2016 to 2017, had the objective of comparing the soil tillage systems to be adopted in crop seasons for stabilization of no-tillage (SPD) in soybean (summer) and sorghum (autumn-winter). The experimental design was a randomized block design, using factorial arrangement with four replications and seven treatments: continuous no-tillage (23 and 24 years of implantation), with minimum tillage, conventional soil tillage with heavy grating, and shisel moldboard pow by three disk plowing followed and no-tillage on each of these soils managed continuously with the same number of harvests followed up to the 7th and 8th harvests. Biometric data from soybean and sorghum cultures, soil physical attributes and amount of total organic carbon were evaluated for comparison of means. The results showed that continuous direct seeding systems presented higher amounts of total organic carbon stock. The increase of soybean grain yield is directly related to the greater presence of plants in the final stand when the soil was prepared with heavy grating follo... (Complete abstract click electronic access below) / Mestre

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Essa dissertação apresenta um estudo sobre o acúmulo de matéria orgânica nos sedimentos do complexo estuarino lagunar Mundaú Manguaba (CELMM) utilizando lipídios (ácidos graxos, esteróis e alcoóis lineares) como marcadores moleculares , com o objetivo de avaliar as fontes (naturais e antrópicas) e a variação espacial e temporal na composição da matéria orgânica sedimentar, assim como a influência dos processos diagenéticos sobre a qualidade e a preservação da mesma. O CELMM é caracterizado por um alto potencial de reciclagem e retenção de materiais e está sujeito a diversas atividades antropogênicas, incluindo a urbanização e as práticas de monocultura de cana-de-açúcar, além de sofrer um processo acelerado de degradação ambiental. Através de análise estatística multivariada foi possível discenir as fontes dos lipídios e, a partir disto, identificar as contribuições de matéria orgânica planctônica (fitoplâncton e zooplâcton), terrígena e bacteriana para os diferentes compartimentos do CELMM. Foi possível identificar um incremento no acúmulo de matéria orgânica de origem autóctona nas lagoas nos últimos anos. Este efeito foi mais significativo em Mundaú, reflexo do maior nível de alteração antrópica nessa lagoa. O nível de contaminação fecal avaliado através de esteróis fecais pode ser considerado de médio a baixo, quando comparados com outros locais que também apresentam influência antrópica significativa. A transformação diagenética da matéria orgânica, avaliada através das razões estanol/esterol, mostrou que a atividade bacteriana no CELMM é significativa ainda na coluna dágua ou na interface água-sedimento, mas que após o soterramento a matéria orgânica fica preservada. / This thesis presents a study on the accumulation of organic matter in the sediments of the complex estuarine lagoon Mundaú Manguaba (CELMM) using lipids (fatty acids, sterols and linear alcohols) as molecular markers to evaluate the sources (natural and anthropogenic) and spatial and temporal variation in the composition of sedimentary organic matter, as well as the influence of diagenetic processes on the quality and preservation of it. The CELMM is characterized by a high potential for recycling and storage of materials and is subject to various anthropogenic activities, including urbanization and practice of monoculture of cane sugar, in addition to suffering an accelerated process of environmental degradation. By multivariate analysis was possible to discern sources of lipids, and from this, identify the contributions of organic matter - plankton (phytoplankton and zooplankton), terrigenous and bacterial - for different sectors CELMM. It was possible to identify an increase in the accumulation of organic matter of autochthonous origin in the lagoons in recent years. This effect was more significant in Mundaú, reflecting the higher level of anthropogenic disturbance at the pool. The level of fecal contamination - assessed through fecal sterols - may be considered medium to low compared with other sites that also have significant human influence. The diagenetic transformation of organic matter as measured by the reasons stanol / sterol, showed that bacterial activity in CELMM is significant even in the water column or sediment-water interface, but that after the burial of organic matter is preserved.

O estoque de matéria orgânica de superfície refere-se a todo material orgânico decomposto ou em decomposição sobreposto ao solo mineral, bem como ao material orgânico misturado às partículas minerais do horizonte A. Este serve como indicador da funcionalidade e integridade de ecossistemas florestais quando o analisamos sob a perspectiva das "Formas de Húmus". Nesta perspectiva o material orgânico se presenta como disposto em camadas internas que variam no peso e espessura de acordo com a atuação dos agentes decompositores locais, e expressa a ciclagem de nutrientes que se dá a partir dos dois principais processos que sintetizam e/ou modulam o funcionamento dos ecossistemas, a produção e a decomposição da matéria orgânica. O modelo de formas de húmus segue uma classificação desenvolvida na Europa que não se aplica perfeitamente às áreas tropicais pela alta variabilidade de ambientes. Estima-se que fatores locais e particulares como características edáficas, estrutura e composição da vegetação, relevo e o microclima podem distorcer esta classificação e diferir significativamente do modelo global. Esta pesquisa buscou o refinamento deste modelo, buscando entender de que modo a pluviosidade efetiva (chuva que atravessa a copa das árvores e chega ao solo), como fenômeno de natureza microclimática, se relaciona com o estoque de matéria orgânica de superfície (sob a perspectiva das formas de húmus) em ambiente de floresta ombrófila montanhosa urbana.Para tal foram executadas análises físicas sobre o estoque de matéria orgânica de superfície, monitoramento da pluviosidade efetiva com pluviômetro experimentais adaptados para esta demanda e análises químicas sobre a água da chuva após lixiviação da matéria orgânica. Foi montada uma estrutura composta de quinze pluviômetros experimentais em uma encosta florestada no Parque Nacional da Tijuca (Rio de Janeiro - RJ) e instalação de pluviômetros eletrônicos em ambientes de céu aberto em áreas adjacentes a esta encosta pertencentes à área do parque. Os resultados indicam que da chuva que cai na floresta, cerca de 15% é interceptada pelas copas e o restante, parte é interceptada pela matéria orgânica do solo. A camada MFB (ou H) é a que retém mais água, indicando que, florestas que a decomposição é rápida no processo de fragmentação e lenta na mineralização, terão mais água retida no estoque de matéria orgânica. As diferentes camadas vão nutrir o solo de maneira diferenciada quando este processo deriva da lixiviação, como o cálcio que é liberado em a maior quantidade pelas camadas mais fragmentadas como a F e a MFB, o potássio e magnésio têm maior disponibilização quando deriva da camada L, indicando que durante este processo estes nutrientes são mais consumidos do que liberados. Foi perceptível que o sódio é bastante abundante na chuva antes mesmo de atingir a matéria orgânica, confirmando estudos anteriores. A utilização deste sistema proposto de pluviômetros experimentais possibilitou entender como esta estratificação interna do estoque de matéria orgânica de superfície acumula água, pois os métodos tradicionais não se baseiam no modelo de formas de húmus, e possibilitou ainda, o a análise do processo de lixiviação e liberação de nutrientes para o solo. / The organic matter stocks surface refers to any organic material in decomposition or decomposed superimposed on mineral soil, and the mixed organic material to the mineral particles of the horizon A. This serves as an indicator of the functionality and integrity of forest ecosystems when analyzed from the perspective of "Humus Forms." In this perspective the organic material presents as layered internal ranging in weight and thickness according to the activities of agents decomposers local and express nutrient cycling that occurs from the two main processes that synthesize and / or modulate the functioning of ecosystems, production and decomposition of organic matter. The model forms humus follows a classification developed in Europe that does not apply perfectly to tropical areas by high environmental variability. It is estimated that local and particular factors as soil characteristics, vegetation structure and composition, topography and microclimate can distort this classification and differ significantly from the global model.This study sought to refine this model, seeking to understand how the effective rainfall (rain crossing the canopy and reaches the ground), as a phenomenon of nature microclimate, relates to the stock of organic matter from the surface (from the perspective forms of humus) in an environment of urban mountainous rainforest.For such analyzes were performed on the physical stock of organic matter from the surface, the effective monitoring of rainfall with rain gauges experimental adapted to this demand and chemical analyzes of rain water after leaching of organic matter. Has assembled a structure composed of fifteen experimental gauges on a forested hill in the Tijuca National Park (Rio de Janeiro - RJ) and installation of electronic gauges in environments of open areas adjacent to slopes belonging to this area of ??the park.The results indicate that the rain that falls in the forest, about 15% is intercepted by the canopy and the remaining portion is intercepted by soil organic matter. The MFB layer (or H) is that retains more water, indicating that forests that the decomposition is faster in the process of fragmentation and slow mineralization have more water retained in the stock of organic matter. The different layers will feed the soil differently when this process is derived from the leaching, as the calcium that is released in the greatest quantity by the layers more fragmented as F and MFB, potassium and magnesium are derived from more readily available when the layer L, during this process indicates that these nutrients are consumed more than released. It was noticeable that sodium is quite abundant in the rain before reaching the organic matter, confirming previous studies. The use of this proposed system gauges experimental possible to understand how this internal stratification of the stock of organic matter accumulated water surface, as the traditional methods are not based on the type of humus forms, and possible further analysis of the the leaching process and release nutrients to the soil.

Made available in DSpace on 2014-06-11T19:30:24Z (GMT). No. of bitstreams: 0 Previous issue date: 2010-05-20Bitstream added on 2014-06-13T20:00:31Z : No. of bitstreams: 1 lobo_tf_dr_botfca.pdf: 1920099 bytes, checksum: 0014cfba7503ac51ffb60927f189b951 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / A disposição final do lodo de esgoto vem se caracterizando como um dos problemas ambientais urbanos mais relevantes da atualidade, e cresce diariamente tanto nos países desenvolvidos quanto naqueles em desenvolvimento, como reflexos da ampliação das redes de coleta e incremento dos níveis de tratamento. O objetivo deste trabalho foi utilizar o lodo de esgoto compostado como fornecimento de N em sistema de sucessão de culturas avaliando o desenvolvimento, nutrição, produtividade das culturas trabalhadas e a melhoria da fertilidade do solo. Os experimentos foram conduzidos na Fazenda São Manuel da Faculdade de Ciências Agronômicas da UNESP, Campus de Botucatu, localizada no município de São Manuel/SP. Antecedendo a instalação do experimento, foram cultivados 2 ciclos consecutivos de girassol semeados em dezembro de 2004 e novembro de 2005, respectivamente, com aplicações de lodo de esgoto, sendo cultivado trigo e triticale para avaliar o efeito residual destas duas aplicações em abril de 2006. Os ensaios presentes neste trabalho foram em sistema de sucessão de culturas (aveia, feijão, triticale, girassol e trigo). Em sistema de semeadura direta, sendo somente o primeiro cultivo, aveia em sistema convencional com lodo de esgoto tratado. Os outros ensaios foram com lodo de esgoto compostado. Adotou-se o delineamento experimental em blocos casualizado constituído por 6 tratamentos e 5 repetições. Os tratamentos foram: T0 – adubação mineral de acordo com o Boletim Técnico 100, mas sem N; T1 – adubação química de acordo com o Boletim Técnico 100 do IAC; T2 – 50% do N proveniente do lodo de esgoto e o restante foi proveniente da adubação química; T3 – 100 % do N proveniente do lodo de esgoto; T4 – 150% do N proveniente do lodo de esgoto; T5 – 200% do N proveniente do lodo de esgoto. Utilizou-se o lodo de esgoto da Estação de Tratamento de Esgoto... / The final display of sewage sludge has been characterized as one of the most relevant environmental problems in the cities; it daily increases in both developed and developing countries, resulting in larger collection networks and increased treatment levels. The aim of this study was to use compost sewage sludge as N supply for crop rotation system, assessing the development, nutrition and productivity of treated cultures and the improvement of soil fertility. The experiments were carried out in São Manuel Farm, which belongs to the School of Agronomical Sciences, UNESP, Botucatu Campus, and is located in São Manuel Municipality, São Paulo State, Brazil. Before the experiment establishment, 2 consecutive sunflower cycles were sown in December 2004 and November 2005, respectively, including sewage sludge application, and wheat and triticale were cultivated to assess the residual effect of those two applications in April 2006. The assays in the present study were done in crop rotation system (oat, bean, triticale, sunflower and wheat). Direct planting system was used only for the first cultivation; oat was in conventional system with treated sewage sludge. The remaining assays included compost sewage sludge. The adopted experimental design was in randomized blocks constituted of 6 treatments and 5 replicates. Treatments were: T0 – mineral fertilization according to Technical Bulletin 100, but without N; T1 – chemical fertilization according to IAC Technical Bulletin 100; T2 – 50% N from sewage sludge and the remaining N from chemical fertilization; T3 – 100% N from sewage sludge; T4 – 150% N from sewage sludge; T5 – 200% N from sewage sludge. The employed sewage sludge was from the Sewage Treatment Plant in Jundiaí Municipality, São Paulo State. Each plot was 100 m2 with 3m spacing between plots in one same block. Oat culture was assessed from the 60th to the 120th day after... (Complete abstract click electronic access below)

The aim of this thesis was to investigate contrasting pasture management strategies on the foraging behaviour, pasture production, carcass characteristics, herbage intake, faecal gas emissions and methane emission by sheep grazing Italian ryegrass (Lolium multiflorum) pastures. The experiment was carried out in 2014 and 2015. The experimental design was a randomized complete block with four replicates and two grazing strategy treatments (traditional rotational stocking method – RT meaning pre- and post-grazing target heights of 25 and 5 cm, respectively and, “rotatinuous stocking” – RN with pre- and post-grazing target heights of 18 and 11 cm, respectively). The grazing management was based on a 1-day strip-grazing regime. Male castrated sheep were used. The actual average sward heights for the RN treatment were 17.9 and 11.1 cm (pre- and post-grazing, respectively) and 27.1 and 7.8 cm for the RT (pre- and post-grazing, respectively). The stocking period in 2014 was 146 and 140 days (RN and RT, respectively) and in 2015 it was 155 and 146 days (RN and RT, respectively). The diurnal animal activities (grazing, ruminating and resting time) did not differ between treatments, with average of 439.6, 166.9 and 85.0 minutes, respectively. The bite rate, feeding station per min and steps per min were greater at the RN than the RT treatment. Grazing time and bite rate were greater in the afternoon than morning in both treatments. Therefore, the daily herbage intake by sheep grazing Italian ryegrass was greater for the RN than the RT treatment (CHAPTER II). The herbage production in the RN was 28% higher than the RT treatment. Individual average daily gain and live weight gain per hectare were greater in the RN than the RT treatment (CHAPTER III). RN treatment presented greater final live weight, carcass and commercial cut weights from grazing sheep than RT treatment (CHAPTER IV). RN treatment had a faecal chemical quality greater than RT treatment, resulting in a greater daily nitrogen excretion per animal and greater faecal CH4 and N2O emissions (CHAPTER VI). The “rotatinuous stocking” (RN) was the better grazing management strategy for mitigation of CH4 emissions by sheep grazing Italian ryegrass, emitting 64% less CH4 per unit area and 170% less CH4 per unit of animal product than the traditional rotational stocking method (RT) (CHAPTER V).

Les microalgues, qui sont à la base des réseaux trophiques aquatiques, peuvent être la cibleindirecte des herbicides provenant des usages agricoles et urbains. Elles sont également en interaction avecd’autres éléments de leur environnement comme la matière organique dissoute (MOD) naturelle, ellemêmesusceptible d’interagir avec les herbicides. Cette thèse a visé à étudier, en milieu contrôlé, l’influencede la MOD naturelle sur la toxicité d’herbicides vis-à-vis de microalgues en cultures monospécifiques nonaxéniques. Ont été considérés de la MOD naturelle d’eau douce et marine, trois herbicides (irgarol, diuronet S-métolachlore) seuls et en mélange, deux espèces de microalgues dulçaquicoles (Gomphonema gracileet Sphaerellopsis sp.) et deux espèces marines (Chaetoceros calcitrans et Tetraselmis suecica). Les effetsont été déterminés sur la croissance, l’efficacité photosynthétique et le contenu relatif en lipides desmicroalgues. En parallèle, l’environnement chimique a été caractérisé en suivant l’évolution de lacomposition et des propriétés de la MOD, ainsi que des concentrations d’herbicides et de leurs métabolites.Les résultats de ces travaux, qui considèrent pour la première fois la MOD naturelle dans sa globalité eninteraction avec des microalgues et des herbicides, démontrent le rôle clé joué par la MOD sur (i) lastimulation de la croissance des quatre espèces de microalgues (et en retour la modification de la MOD parcelles-ci), (ii) la modulation de la toxicité des herbicides et suggèrent (iii) la capacité de Sphaerellopsis sp.et/ou de ses bactéries associées de biodégrader le diuron. / Microalgae are at the basis of aquatic food webs and may be the indirect target of herbicidesfrom agricultural and urban uses. They also interact with other compounds from their environment such asnatural dissolved organic matter (DOM), which can itself interact with herbicides. This thesis aimed tostudy, in laboratory controlled conditions, the influence of natural DOM on herbicide toxicity to microalgaeby using monospecific, non-axenic cultures. The experiments included: natural freshwater and marineDOM, three herbicides (irgarol, diuron and S-metolachlor) singly and in mixtures, two freshwatermicroalgae (Gomphonema gracile and Sphaerellopsis sp.) and two marine microalgae (Chaetoceroscalcitrans and Tetraselmis suecica). Effects were evaluated on microalgae growth, photosyntheticefficiency and relative lipid content. At the same time, changes in chemical environment over theexperiments were measured through DOM composition and properties, as well as the concentrations inherbicides and their metabolites. The results of this work, which consider for the first time natural DOM asa whole, interacting with microalgae, their associated bacteria and herbicides, demonstrate the key roleplayed by DOM in (i) the growth stimulation of four microalgae (and in return the DOM changes inducedby microalgae), (ii) the modulation of herbicide toxicity and suggest (iii) the ability of Sphaerellopsis sp.and/or its associated bacteria to biodegrade diuron in non-axenic conditions.

My work targets the change in content of the organic soil karbon and basic cations in relation to changes of area usage and agricultural management of the chosen special {--} interest places of Stropnicko. In the monitored period from 2001 till 2007, the soil organic mass markedly fell off. The greatest decline was in the forest ecosystem in all researched basins. Decline of organic soil karbon content was also found on permanent grass growth, but it was much less than in the forests. On the contrary mild improvement turns out on the arable land. Next pH value of soil leach was monitored. The greatest change was shown in the forests. The greatest increase of PH value was at the area of Pasecký potok. In other basins, expected Veverský potok, pH value increased too. On the contrary, there is decline of pH value on the permanent grass growth and arable land . There were not statistically great advancements between 2001 and 2007 in the soil mineral reserve, especially of the basic soil cations. The significant decline of sodium is the exception. I have suggested steps that lead to the steady way of farming in the agricultural foothills. I have recommended to increase supplied barnyard manure into arable land, the optimalization of cow units for pasture area and the gradation of the forest communities to deciduous, eventually mixed stands, according to the vegetation levels.

Seven clover sampes (Trifolium pratense L.) were collected at three different miters I (n = 3), II (n = 3) and III (n = 1) during the growing season from 10th of May to 17th of August. The samples were analyzed for chemical composition, gross energy (BE) content, in vivo sheep digestibility of organic matter (KS OH) and gross energy (KS BE) and in situ rumen degradability of organic matter and neutral detergent fibre (NDF). The contents of ash, crude protein (NL), crude fibre (CF), NDF, acid detergent fibre (ADF), acid detergent lignin (ADL) and BE were significantly (P < 0,05) affected by the date of cutting time. The averaged values were for ash 119,2 g/kg of dry matter, NL 197,7 g/kg of dry matter, CF 214,1 g/kg of dry matter, NDF 400,7 g/kg of dry matter, ADF 296,2 g/kg of dry matter, ADL 73,8 g/kg of dry matter and BE 18,2 MJ/kg of dry matter. KS OH and KS BE generally decreased with higher dates of cutting time. On average KS OH and KS BE amounted 72,4 % and 70,2 %, respectively. The effective ruminal degradability of organic matter (EDOH) was in average 81,7 % for miter I, 79,7 % for miter II and 75,2 % for miter III. In situ organic matter degradability characteristics were in average 41,9 % for the immediately degradable (soluble) fraction (parameter a), 47,1 % for the potential degradable fraction (parameter b) and 0,105 h-1 for the fractional rate of degradation (parameter c). The effective ruminal degradability of NDF (EDNDF) also generally decreased (P < 0,05) with increasing date of cutting time with values of 63,0 % for miter I, 59,7 % for miter II and 51,6 % for miter III. Strong correlation (P < 0,05) was observed between the EDOH and EDNDF (r = 0,979).