This thesis presents two interrelated studies that consider nutrient management and seasonal changes in recharge on agricultural lands within the context of source water protection. The research focuses first on the management of the risk to groundwater quality through the implementation of various nutrient management practices and secondly considers the dynamic nature of the transport pathway to the groundwater system associated with seasonal changes in climate and hydrology. The combined results provide insight into several of the key factors influencing the protection of groundwater sources within the agricultural landscape. Field work was completed between 2009 and 2010 on an agricultural field near the City of Woodstock, Ontario. The site is located within a source water protection area; the two-year travel time zone of the Thornton Well Field which represents the primary water supply for the City of Woodstock and which has experienced chronic increases in nitrate concentrations over the last few decades. The wells are completed in glacial overburden consisting of intermingling sand and gravel till aquifers which overly a limestone bedrock aquifer. Agricultural best or beneficial management practices (BMPs) field have been implemented and monitored since 2004. The BMPs were adopted in order to reduce nitrogen losses to the aquifer, and consisted of a reduction in nitrogen fertilizer application rates over a series of agricultural fields located near the well The first study is a one year experiment designed to compare alternative nutrient management practices for corn. Combinations of fertilizer treatments with or without a legume cover crop (red clover) were assessed. The fertilizer treatments studied were: a polymer coated urea (slow-release fertilizer) applied at planting, a conventional urea applied at planting, side-dress treatment of a solution of urea and ammonium nitrate in water containing 28% nitrogen with two different application rates applied in the early summer, and a control. The legume cover crop was incorporated in the soil in the previous fall, and acts as a slow release fertilizer as nitrogen is made available to the following crop as the plants decompose. Treatments were compared based on crop yield, overall economic return, and the potential for nitrate leaching. The potential for nitrate leaching was evaluated with bi-weekly shallow soil core during the growing season, and deep soil cores taken before planting, after harvest and the following spring. The deep cores allowed changes in nitrate storage below the rooting zone to be assessed. The results of this study highlight the importance of timing of fertilizer applications and rate of fertilizer applications. Treatments which provide a delay in the release or application of fertilizer, the polymer-coated urea, the calculator-rate side-dress and the clover cover crop, were found to be advantageous. The polymer-coated urea treatments and side-dress treatments were found to reduce leaching compared to the conventional urea treatment. Treatments with the clover cover crops were not found to reduce crop yields or increase leaching potential, and lower fertilizer costs associated to this practice were found to have a positive economic effect. Plots treated with the high-rate side-dress fertilizer application lost more nitrate to the subsurface compared to the other treatment options, and an economic disadvantage was observed as yields did not compensate for higher fertilizer costs. The study highlights the advantages of the different treatments under study, which may be used to inform policy makers and farmers in the selection of economically and environmentally sustainable nutrient management BMP options. Groundwater monitoring at the site over the years has indentified interesting recharge dynamics, particularly in the vicinity of an ephemeral stream which develops annually during spring and winter melt events in a low lying area of the study site. It was hypothesized that rapid recharge could occur beneath the stream allowing for surface water to quickly reach groundwater, posing a threat to municipal water wells. The current framework of source water protection does not take into account the potential risk posed by this type recharge event. At this field site, rapid infiltration associated with this type of event may pose a risk to drinking water quality due to the proximity of the stream to the pumping wells and the nature of the aquifer. The second study examines rapid groundwater recharge processes beneath the ephemeral stream during the course of a spring melt in 2010. The goals of the study were to quantify recharge at one location beneath the stream and to assess whether temperature variations above the water table can be used as a tracer to reasonably estimate recharge during a short live recharge event. A novel housing for the temperature sensors was designed in order to deploy and position them into gravelly materials within the vadose zone, which reduced the potential for the formation of preferential pathways and permitted the retrieval of the sensors at a later date. Field data were collected during the course of the spring melt period from a network of groundwater monitoring wells and subsurface temperature sensors. Spatial and temporal changes in groundwater geochemistry, hydraulic head and temperature were were used to characterize recharge dynamics at the field site. Recharge beneath a segment of the ephemeral stream was quantified through the numerical analysis of the field data using Hydrus 1-D, a one-dimensional numerical model designed to simulate soil water flow and heat transport in variably saturated porous media. Site specific data were used to create the model domain, provide estimates of physical parameters, and to define initial and time variable boundary conditions. Model parameters were first calibrated by simulating periods where it was expected that soils would be gravity drained with minimal soil water flow, and then further refined by simulating the period when the ephemeral stream was present. A final set of parameters was determined, and the initial gravity drained conditions were re-simulated. The model was able to reproduce field observations under different flow scenarios using the final set of parameters, suggesting that the conceptual model and final model domain representative of the actual field conditions. The successful simulation of the field data sets under the different flow scenarios also increases confidence in the uniqueness of the model results. The model estimated that 0.15 m of recharge occurred beneath the instrumented site during the period between March 9th and March 22nd of 2010 when the ephemeral stream was present. This represents approximately a third of the expected total annual recharge for this location. Regional changes in hydraulic head, groundwater temperature and groundwater chemistry provided additional insight into the dynamic nature of the recharge process during the spring meld period and further illustrated the spatial variability of the aquifers’ response to the stream. The study found that the use of temperature as a tracer provided useful and quantifiable insight into recharge phenomena. The results of this study suggest that high rates of rapid recharge occur beneath the ephemeral stream, and are spatially variable. This type of focused infiltration that occurs during the spring melt may represent a risk to municipal water quality if the infiltrating waters are carrying contaminants.

Made available in DSpace on 2016-08-12T19:15:25Z (GMT). No. of bitstreams: 1 KassiaJBO_DISSERT.pdf: 1351352 bytes, checksum: 1f12aaa9e29f565fec103eb2a5f09efe (MD5) Previous issue date: 2014-02-24 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The experiment was conducted at the Experimental Farm 'Rafael Fernandes' of the Universidade Federal Rural do Semi-Árido (UFERSA), located in the district of Alagoinha, from August 2012 to February 2013 with the objective of evaluating the agrieconomic performance of the beet and arugula intercropped as a function of roostertree amounts incorporated into the soil and spatial arrangements of the component crops. The experimental design was of randomized complete blocks with five replications, with the treatments arranged in a 4 x 3 factorial scheme. The treatments consisted of the combinations of four amounts of roostertree incorporated into the soil (10, 25, 40 and 55 t ha-1 of dry matter) and three spatial arrangements (2B:2A, 3B:3A and 4B:4A), corresponding rows of beet (B) alternated with rows of arugula (A). The characteristics evaluated in the beet were: plant height, number of leaves per plant, total and commercial productivity, productivity of classified roots, fresh and dry mass of shoot; in the arugula were: plant height, number of leaves per plant, dry mass of shoot and yield of green mass; in the diagnostic leaves of beet and arugula were evaluated the contents of N, P, K; in the soil were assessed the amounts of bacterial and fungal colonies present before and after planting, as well as, the nutrient contents: N, P, K, pH, CEC and soil organic matter before and after sowing. In the intercropping systems were evaluated the productive efficiency index, the canonical variable score, gross income, net income, rate of return and profit margin. The highest agrieconomic performance of the intercropping beet and arugula was obtained in the amount of 55 t ha-¹ of roostertree incorporated into the soil and in the spatial arrangement of 2B: 2A. The amount of fungi and bacteria of the soil increased with increasing amounts of roostertree added to the soil in the arrangement of 2B: 2A. The multivariate method compared to the univariate method applied to the productive efficiency index was quite effective in determining the best arrangement 2B: 2A of the bicropping of arugula intercropped with beet. It is economically viable for the farmer to use the roostertree as green manure in the beet production intercropped with arugula / O experimento foi conduzido na Fazenda Experimental Rafael Fernandes da Universidade Federal Rural do Semi-Árido (UFERSA), localizada no distrito de Alagoinha, no período de agosto de 2012 a fevereiro de 2013, com o objetivo de avaliar o desempenho agroeconômico da beterraba e rúcula consorciadas em função de quantidades de flor-de-seda incorporadas ao solo e arranjos espaciais das culturas componentes. O delineamento experimental usado foi de blocos completos casualizados com cinco repetições, com os tratamentos arranjados em esquema fatorial 4 x 3. Os tratamentos consistiram de quatro quantidades de flor-de-seda incorporadas ao solo (10; 25; 40 e 55 t ha-1 de matéria seca) e três arranjos espaciais (2B:2R, 3B:3R e 4B:4R), que corresponderam a fileiras de beterraba (B) alternadas com fileiras de rúcula (R). As características avaliadas na beterraba foram: altura de plantas, número de folhas por planta, produtividade total e comercial, produtividade classificada de raízes, massa fresca e seca da parte aérea. Já na rúcula foram: altura de plantas, número de folhas por planta, massa seca da parte aérea e rendimento de massa verde. Nas folhas diagnósticas de beterraba e rúcula foram avaliados os níveis de N, P, K. Por sua vez, no solo foram avaliadas as quantidades de colônias de bactérias e fungos presentes antes e após o plantio, bem como os teores nutrientes: N, P, K, pH, CTC e matéria orgânica do solo antes e depois do plantio. Índices de eficiência agronômica e econômica de sistemas consorciados, tais como: índice de eficiência produtiva, escore da variável canônica, renda bruta, renda líquida, taxa de retorno e índice de lucratividade também foram avaliados. O maior desempenho agroeconômico para o consórcio de beterraba e rúcula foi obtido na quantidade de 55 t ha-¹ de flor-de-seda incorporada ao solo e no arranjo 2B:2R. A quantidade de fungos e bactérias do solo aumentou com as quantidades crescentes da flor-de-seda incorporadas ao solo no arranjo 2B:2R. O método multivariado quando comparado com o univariado aplicado ao índice de eficiência produtiva foi bastante eficaz na determinação do melhor arranjo 2B:2R do bicultivo de rúcula com beterraba. Nas condições do experimento, é economicamente viável para o agricultor o uso da flor-de-seda como adubo verde na produção beterraba consorciada com rúcula

Made available in DSpace on 2016-08-12T19:18:46Z (GMT). No. of bitstreams: 1 KassiaJBO_DISSERT.pdf: 1351352 bytes, checksum: 1f12aaa9e29f565fec103eb2a5f09efe (MD5) Previous issue date: 2014-02-24 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The experiment was conducted at the Experimental Farm 'Rafael Fernandes' of the Universidade Federal Rural do Semi-Árido (UFERSA), located in the district of Alagoinha, from August 2012 to February 2013 with the objective of evaluating the agrieconomic performance of the beet and arugula intercropped as a function of roostertree amounts incorporated into the soil and spatial arrangements of the component crops. The experimental design was of randomized complete blocks with five replications, with the treatments arranged in a 4 x 3 factorial scheme. The treatments consisted of the combinations of four amounts of roostertree incorporated into the soil (10, 25, 40 and 55 t ha-1 of dry matter) and three spatial arrangements (2B:2A, 3B:3A and 4B:4A), corresponding rows of beet (B) alternated with rows of arugula (A). The characteristics evaluated in the beet were: plant height, number of leaves per plant, total and commercial productivity, productivity of classified roots, fresh and dry mass of shoot; in the arugula were: plant height, number of leaves per plant, dry mass of shoot and yield of green mass; in the diagnostic leaves of beet and arugula were evaluated the contents of N, P, K; in the soil were assessed the amounts of bacterial and fungal colonies present before and after planting, as well as, the nutrient contents: N, P, K, pH, CEC and soil organic matter before and after sowing. In the intercropping systems were evaluated the productive efficiency index, the canonical variable score, gross income, net income, rate of return and profit margin. The highest agrieconomic performance of the intercropping beet and arugula was obtained in the amount of 55 t ha-¹ of roostertree incorporated into the soil and in the spatial arrangement of 2B: 2A. The amount of fungi and bacteria of the soil increased with increasing amounts of roostertree added to the soil in the arrangement of 2B: 2A. The multivariate method compared to the univariate method applied to the productive efficiency index was quite effective in determining the best arrangement 2B: 2A of the bicropping of arugula intercropped with beet. It is economically viable for the farmer to use the roostertree as green manure in the beet production intercropped with arugula / O experimento foi conduzido na Fazenda Experimental Rafael Fernandes da Universidade Federal Rural do Semi-Árido (UFERSA), localizada no distrito de Alagoinha, no período de agosto de 2012 a fevereiro de 2013, com o objetivo de avaliar o desempenho agroeconômico da beterraba e rúcula consorciadas em função de quantidades de flor-de-seda incorporadas ao solo e arranjos espaciais das culturas componentes. O delineamento experimental usado foi de blocos completos casualizados com cinco repetições, com os tratamentos arranjados em esquema fatorial 4 x 3. Os tratamentos consistiram de quatro quantidades de flor-de-seda incorporadas ao solo (10; 25; 40 e 55 t ha-1 de matéria seca) e três arranjos espaciais (2B:2R, 3B:3R e 4B:4R), que corresponderam a fileiras de beterraba (B) alternadas com fileiras de rúcula (R). As características avaliadas na beterraba foram: altura de plantas, número de folhas por planta, produtividade total e comercial, produtividade classificada de raízes, massa fresca e seca da parte aérea. Já na rúcula foram: altura de plantas, número de folhas por planta, massa seca da parte aérea e rendimento de massa verde. Nas folhas diagnósticas de beterraba e rúcula foram avaliados os níveis de N, P, K. Por sua vez, no solo foram avaliadas as quantidades de colônias de bactérias e fungos presentes antes e após o plantio, bem como os teores nutrientes: N, P, K, pH, CTC e matéria orgânica do solo antes e depois do plantio. Índices de eficiência agronômica e econômica de sistemas consorciados, tais como: índice de eficiência produtiva, escore da variável canônica, renda bruta, renda líquida, taxa de retorno e índice de lucratividade também foram avaliados. O maior desempenho agroeconômico para o consórcio de beterraba e rúcula foi obtido na quantidade de 55 t ha-¹ de flor-de-seda incorporada ao solo e no arranjo 2B:2R. A quantidade de fungos e bactérias do solo aumentou com as quantidades crescentes da flor-de-seda incorporadas ao solo no arranjo 2B:2R. O método multivariado quando comparado com o univariado aplicado ao índice de eficiência produtiva foi bastante eficaz na determinação do melhor arranjo 2B:2R do bicultivo de rúcula com beterraba. Nas condições do experimento, é economicamente viável para o agricultor o uso da flor-de-seda como adubo verde na produção beterraba consorciada com rúcula

Made available in DSpace on 2016-08-31T13:15:09Z (GMT). No. of bitstreams: 1 GiullianaMMS_DISSERT.pdf: 3079970 bytes, checksum: f7be23cf2e8ddbe7ac6f9800be3de04c (MD5) Previous issue date: 2011-01-24 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Green manuring is the practice of incorporating undecomposed plant tissue to the soil, to maintain or increase soil fertility. One of the most used plants as green manure is Crotalaria juncea, with presents advantages compared to other legumes. This work was conducted with the objective of evaluating the effect of organic manures and plant densities on Crotalaria juncea growth, accumulation of nutrients in its shoots and in the soil, and also on rice yield. The trial was developed in an experimental area of Semiarid Federal Rural University, in Mossoró, RN, Brazil. Experimental design was a randomized blocks in a 4 x 3 factorial scheme, with four replications. Factors studied were organic manures (chicken manure, earthworm humus and control) and plant spacing (10 x 10, 14 x 14, 17x 17 and 20 x 20 cm). Determinations realized were: fresh and dry mass of shoot and root of crotalaria, shoot contents of N, P and K and soil pH, electrical conductivity (EC), PST and contents of C, N, P, K, Na, Ca and Mg after decomposition of crotalaria plants, and also rice production components (panicle number in 10 plants, grain weight in 10 plants; empty grain weight in 10 plants; mass of 100 grains). Data were submitted to variance analysis. The results related to the spacing were subjected to linear regression and data on the type of fertilization were subjected to Duncan test at 5% probability. Plant density of crotalaria provided a positive linear effect on shoot dry and green mass and per hectare accumulated amounts of N, P and K of shoot, and also a negative linear effect on root dry mass. Nutrient content per plant were not influenced by plant density and manure type, while manure type influenced only the P content per plant. Chicken manure provided the higher values of shoot fresh (24,55 t ha-1), and dry mass (5,89 t ha-1) and root dry mass (20,23 g) of crotalaria and the higher values of accumulated amounts per hectare of N(122,68 kg ha-1), P (33,38 kg ha-1) and K (78,00 kg ha-1) on shoot. Plant density of crotalaria did not influenced rice production components, while manure type only influenced mass of empty grains. / A adubação verde é a prática de se incorporar, ao solo, o tecido vegetal não decomposto, visando manter ou aumentar a fertilidade do solo. Uma das plantas mais utilizadas como adubo verde é a Crotalaria juncea, apresentando vantagens frente às outras leguminosas. O objetivo deste trabalho foi avaliar o efeito de adubos orgânicos e densidades de semeadura sobre o desenvolvimento da Crotalaria juncea, acúmulo de nutrientes na parte aérea e no solo e produtividade de arroz. O experimento foi desenvolvido em área experimental da Universidade Federal Rural do Semi-Árido, Mossoró, RN. O delineamento experimental foi o de blocos ao acaso em esquema fatorial do tipo 4 x 3, com quatro repetições. Os fatores estudados foram três tipos de adubação (esterco de galinhas, húmus de minhoca e testemunha) e quatro espaçamentos entre plantas (10 x 10, 14 x 14, 17x 17 e 20 x 20 cm). Foram realizadas as seguintes determinações: massa verde e seca e teores de N, P e K da parte aérea da crotalaria; massa seca da raiz, pH, condutividade elétrica (CE), PST e teores de C, N, P, K, Na, Ca e Mg do solo após a decomposição da crotalária; além de componentes de produção do arroz ( número de panículas em 10 plantas; massa de grãos chochos e massa de grãos cheios em 10 plantas; massa de 100 grãos cheios) . Os dados foram submetidos à análise de variância. Os resultados relacionados ao espaçamento foram submetidos à regressão linear e os dados relativos ao tipo de adubação foram submetidos ao teste de Duncan a 5% de probabilidade. A densidade de semeadura da Crotalaria juncea proporcionou efeito linear positivo sobre sua MVPA, MSPA e quantidades acumuladas por hectare de N, P e K na parte aérea, além de efeito linear negativo sobre a MSR. Os teores de nutrientes por planta não foram influenciados pelos espaçamentos e os tipos de adubo utilizados influenciaram apenas o teor de fósforo por planta. A utilização do esterco de galinha proporcionou os maiores valores de MVPA (24,55 t ha-1), MSPA (5,89 t ha-1) e MSR (20,23 g) da crotalária e os maiores valores das quantidades acumuladas por hectare de N (122,68 kg ha-1), P (33,38 kg ha-1) e K (78,00 kg ha-1) na parte aérea. A densidade de plantas da crotalária não influenciou os componentes de produção do arroz, enquanto que os tipos de adubo influenciaram apenas a massa de grãos chochos.

Submitted by Lara Oliveira (lara@ufersa.edu.br) on 2017-08-16T22:44:21Z No. of bitstreams: 1 EdilsonCM_TESE.pdf: 1574502 bytes, checksum: 163fe4f69d873b6b97a6e82ae6ad6c4a (MD5) / Approved for entry into archive by Vanessa Christiane (referencia@ufersa.edu.br) on 2017-08-17T22:37:52Z (GMT) No. of bitstreams: 1 EdilsonCM_TESE.pdf: 1574502 bytes, checksum: 163fe4f69d873b6b97a6e82ae6ad6c4a (MD5) / Made available in DSpace on 2017-08-17T22:38:01Z (GMT). No. of bitstreams: 1 EdilsonCM_TESE.pdf: 1574502 bytes, checksum: 163fe4f69d873b6b97a6e82ae6ad6c4a (MD5) Previous issue date: 2016-12-12 / The present work was conducted from August to November of 2014 at the 'Rafael Fernandes' Experimental Farm of the Federal Rural Semi-Arid University (FRSAU), with the objective of evaluating the viability of beet and vegetable-cowpea intercropping under fertilization with roostertree biomass and spatial arrangements of component cultures. The experimental design was a randomized complete block with four replications and the treatments arranged in a 4 x 3 factorial scheme, resulting from the combination of four quantities of roostertree biomass incorporated in the soil (20, 35, 50 and 65 t ha-1 on a dry basis) and three spatial arrangements between component cultures (2: 2, 3: 3 and 4: 4). The agronomic characteristics evaluated in the beet were: total, commercial and classified productivities of roots (extra, extra A, extra AA, great and scrap roots). In the vegetable-cowpea were evaluated: number of green pods per area, yield and dry weight of green pods, number of green grains per pod, weight of 100 green grains, and yield of green and dry grains. The agronomic and economic efficiency of the intercropping systems studied was evaluated through the indices of land equivalent ratio and productive efficiency, canonical variable score, gross and net returns, rate of return and net profit margin. There was no significant interaction between amounts of roostertree biomass incorporated into the soil and spatial arrangements for any characteristic evaluated in the beet, cowpea and the indices. The highest agronomic efficiency was obtained in the amount of 65 t ha-1 of roostertree biomass, while the highest economic efficiency was obtained in the amount of 28 t ha-1 of this manure. In absolute terms, the 2: 2 spatial arrangement provided the highest agroeconomic efficiency of the intercropped systems / O presente trabalho foi conduzido de agosto a novembro de 2014 na Fazenda Experimental "Rafael Fernandes" da Universidade Federal do Semi-Árido Rural (UFERSA), com o objetivo de avaliar a viabilidade do cultivo consorciado de beterraba e caupi-hortaliça sob adubação com biomassa de flor-de-seda e arranjos espaciais das culturas componentes. O delineamento experimental utilizado foi o de blocos casualizados com quatro repetições e os tratamentos arranjados em esquema fatorial 4 x 3, resultantes da combinação de quatro quantidades de biomassa de flor-de-seda incorporadas ao solo (20, 35, 50 e 65 t ha-1 em base seca) e três arranjos espaciais entre as culturas componentes (2:2, 3:3 e 4:4). As características agronômicas avaliadas na beterraba foram: produtividade total, comercial e classificada de raízes (em extra, extra A, extra AA, grandes e sucatas). No caupi-hortaliça foram avaliados, número de vagens verdes por área, rendimento e peso seco de vagens verdes, número de grãos verdes por vagem, peso de 100 grãos verdes e rendimento de grãos verdes e secos. A eficiência agronômica e econômica dos sistemas de consórcio estudados foi avaliada através dos índices de uso eficiente da terra e de eficiência produtiva, da pontuação da variável canônica, dos retornos bruto e líquido, da taxa de retorno e do indice de lucratividade. Não houve interação significativa entre as quantidades de biomassa de flor-de-seda incorporadas ao solo e os arranjos espaciais para qualquer característica avaliada na beterraba, caupi-hortaliça e nos índices agro-econômicos. A maior eficiência agronômica foi obtida na quantidade de 65 t ha-1 de biomassa de flor-de-seda, enquanto a maior eficiência econômica foi obtida na quantidade de 28 t ha-1 desse adubo. Em termos absolutos, o arranjo espacial 2: 2 proporcionou a maior eficiência agro-econômica dos sistemas consorciados / 2017-08-16

Considering soil management systems, are rare the research projects that are carried on by a time period long enough to several soil attributes may be expressed conveniently. The no-till system influences several soil attributes and in this context, this study aimed to evaluate the effect of tillage system with the use of cover crops in winter and summer, on some chemical and physical soil attributes after long-term adoption of the system. Also aimed to evaluate the corn grain yield, dry matter production and carbon by different cropping systems, the stock of organic carbon and nitrogen in the soil, and also to investigate the no-till effect in reducing soil loss and water compared with the soil in its original state and the soil kept permanently uncovered and exposed to climate action. The experiment began in 1991 in a soil classified as Paleudalf. The experiment uses, since 2001, as treatments, the crop systems described as follows: (1) Corn (Zea mays L.) + jack bean (Canavalia ensiformis DC) / Soybean (Glycine max (L.) Merr.) (MFP), (2) Soil Permanently Discovered (SDES), (3) Maize / fallow / soybean / fallow (POU), (4) Corn / ryegrass (Lolium multiflorum Lam) + common vetch (Vicia sativa) / soybean / common vetch + rye grass (ryegrass) (AZEV), (5) Maize + velvet bean (Styzolobium cinereum) / Soybean (MUC), (6) Native pasture (CNA), and (7) Maize / oilseed radish (Raphanus sativus L. var. oleiferus Metzg.) / Soybean / oilseed radish (NFO). The results showed that the soil permanently uncovered causes severe damages in attributes of soil fertility, mainly the content of organic matter and soil potassium. The analysis of only soil pH was not sufficient to characterize the state of soil acidity, it is necessary to know the concentration of other components such as aluminum exchangeable and levels of calcium + magnesium. The residual effect of lime application before the implementation of no-tillage, in the value of pH, exchangeable aluminum and phosphorus, exceed 16 years. There was a direct relationship between the pH of the soil and its organic matter content, and an inverse relationship between the value of pH and aluminum, with the increasing depth in the soil for all treatments. For the physical attributes evaluated, the results showed that the maintenance of the soil surface permanently unprotected promotes rapid degradation of them, with formation of surface sealing and reduced water infiltration. The soil total porosity and macroporosity, 0.0.- 0.10 m depth, were closely related. The resistance penetration showed higher resistance in the surface layer (up to 0.03 m) of treatment SDES, and NFO presented the highest values at depths of 0.16 and 0.18 m. Lower rates of water infiltration in soil were observed over all time periods (5, 10, 15, 20, 30, 60, 90 and 120 min) studied, in the treatments SDES and CNA, while the others stay constantly above these and similar. No-tillage with the use of cover crops, after a long period of use, was efficient in maintaining physical attributes, such as density and porosity of soil conditions favorable to plant growth, while other attributes that improved, as the rate of water infiltration, compared with its initial condition of native pastures. Regarding the production of corn, no-till system using green manure in summer and winter, after a long period, provided higher yields than systems that use fallow. The soil cultivation from a native condition determined losses in their organic carbon content, but this can be recovered with the use of no-tillage system with a high input of plant residues rich in carbon and nitrogen. Maintenance of the surface soil exposed to erosion for a long period, caused significant losses in its carbon content and total nitrogen. No-tillage with the use of summer green manures (velvet bean) and winter (rye + vetch), promoted increases in the organic carbon stock in the soil layer of 0.0 0.05 m in relation to their initial stock. However, the layer from 0.0 to 0.20 m depth, none crop system has reached the rated values found in the reference treatment, in this case, the native grasses. The results for soil and water conservation were amazing. The maintenance of soil surface exposed rain erosive action for a long period, led to the progressive loss of a soil layer of about 1 cm per year, equivalent to approximately 150 t ha-1 of soil. No-tillage had, in some years, water losses smaller than those found under native pasture. Compared with the losses sustained in soil continuously discovered, the reduction of soil loss by notillage system reached 99.9%. No-tillage was more effective in reducing soil loss than the loss of water in crop systems. The wettest and most erosive rains occurred in the months from October to March, coinciding with the period for the development and the grain harvest of summer crops, for the conditions of Santa Maria, RS. / Em se tratando de sistemas de manejo do solo, são raros os trabalhos de pesquisa que são conduzidos por um período longo o suficiente para que muitos atributos do solo possam expressar-se convenientemente. O sistema plantio direto influencia muitos atributos do solo. O presente estudo teve como objetivos avaliar o efeito do sistema plantio direto com uso de plantas de cobertura de inverno e verão em alguns atributos químicos e físicos do solo, após 16 anos de adoção. Objetivou também avaliar a produtividade de grãos de milho, a produção de matéria seca e carbono pelos diferentes sistemas de culturas, o estoque de carbono orgânico e nitrogênio no solo, além de verificar o efeito dos diferentes sistemas de culturas na redução das perdas de solo e água, em comparação com o solo em seu estado original e com o solo mantido permanentemente descoberto e exposto a ação do clima. O experimento teve início no ano de 1991, em um solo classificado como Argissolo Vermelho distrófico arênico. O mesmo utiliza, desde o ano 2001, como tratamentos, os seguintes sistemas de culturas: (1) Milho (Zea mays L.) + feijão de porco (Canavalia ensiformis DC)/soja (Glycine max (L.) Merr.) (MFP); (2) Solo permanentemente descoberto (SDES); (3) Milho/pousio/soja/pousio (POU); (4) Milho/azevém (Lolium multiflorum Lam.) + ervilhaca comum (Vicia sativa)/soja/azevém + ervilhaca comum (AZEV); (5) Milho + mucuna cinza (Styzolobium cinereum)/soja (MUC); (6) Campo nativo (CNA); e (7) Milho/nabo forrageiro (Raphanus sativus L. var. oleiferus Metzg.)/soja/nabo forrageiro (NFO). Os resultados obtidos demonstraram que o solo mantido permanentemente descoberto influenciou negativamente os atributos de fertilidade do solo avaliados, principalmente o conteúdo de matéria orgânica e potássio do solo. A análise apenas do pH do solo não foi suficiente para caracterizar o estado de acidez do solo, sendo necessário conhecer a concentração dos demais componentes, como o alumínio trocável e os teores de cálcio + magnésio. O efeito residual da aplicação de calcário, antes da implantação do sistema plantio direto, no valor do pH, teor de alumínio e fósforo trocável, ultrapassou 16 anos. Verificou-se uma relação direto entre o valor do pH do solo e o seu teor de matéria orgânica, e uma relação inversa entre o valor do pH e o teor de alumínio trocável, com o incremento na profundidade no solo, para todos os tratamentos avaliados. Para os atributos físicos avaliados, os resultados demonstraram que a manutenção da superfície do solo permanentemente descoberta e desprotegida promove intensa degradação dos mesmos, com formação de selamento superficial e redução da infiltração de água. A porosidade total e a macroporosidade do solo, até 0,10 m de profundidade, apresentaram estreita relação entre si. A resistência do solo ao penetrômetro evidenciou uma camada de maior resistência na superfície (até 0,03 m) do tratamento SDES, e o NFO apresentou os maiores valores nas profundidades de 0,16 e 0,18 m. Menores taxas de infiltração de água no solo foram verificadas, ao longo de todos os tempos avaliados (5, 10, 15, 20, 30, 60, 90 e 120 min), nos tratamentos SDES e CNA, enquanto os demais mantiveram-se constantemente acima destes e semelhantes entre si. O sistema plantio direto com uso de plantas de cobertura do solo, após 16 anos de utilização, mostrou-se eficiente em manter atributos físicos, como a densidade e porosidade do solo em condições favoráveis ao desenvolvimento vegetal, ao mesmo tempo em que melhorou outros atributos, como a taxa de infiltração de água, em comparação com a condição inicial de campo nativo. Com relação a produção de grãos de milho, o sistema plantio direto com utilização de adubos verdes de verão e inverno proporcionou maiores rendimentos do que o sistema que utiliza pousio invernal. O cultivo do solo a partir de um campo nativo determinou perdas no conteúdo de carbono orgânico, porém este foi possível de ser recuperado com a utilização de plantio direto com elevado aporte de resíduos vegetais ricos em carbono e nitrogênio, como ocorreu no tratamento AZEV. A manutenção da superfície do solo exposta aos agentes erosivos provocou perdas significativas no conteúdo de carbono e nitrogênio total. O sistema plantio direto com utilização de adubos verdes de verão (mucuna) e de inverno (azevém+ervilhaca) promoveu incrementos no estoque de carbono orgânico total do solo na camada superficial, de 0,0 0,05 m, em relação a seu estoque inicial. Contudo, na camada de 0,0 0,20 m de profundidade, nenhum sistema de culturas avaliado alcançou os valores encontrados no tratamento referência, no caso, o campo nativo. Os resultados referentes à conservação do solo e da água foram surpreendentes. A manutenção da superfície do solo exposta às condições climáticas e à ação erosiva da chuva, por 16 anos, determinou a perda progressiva de uma camada de solo de aproximadamente 1 cm de espessura por ano, equivalente a aproximadamente 150 t ha-1 ano-1 de solo. O sistema plantio direto promoveu, em alguns anos, perdas de água menores do que as verificadas em campo nativo. Em comparação com as perdas verificadas em solo permanentemente descoberto, a redução das perdas de solo pelo sistema plantio direto chegou a 99,9%. O plantio direto foi mais eficiente em reduzir as perdas de solo do que as perdas de água das áreas com sistemas de culturas. As maiores precipitações e as chuvas mais erosivas ocorreram nos meses de outubro a março, coincidindo com o período destinado à implantação e a colheita de grãos das culturas de verão, para as condições de Santa Maria, RS.

Made available in DSpace on 2016-06-02T18:57:41Z (GMT). No. of bitstreams: 1 4585.pdf: 3982534 bytes, checksum: e0d9b8f2f41f1b6d65989b77ee23cf20 (MD5) Previous issue date: 2012-06-22 / Many farmers consider Agroecology a tool to produce sustainably. By changing their production systems, changing crops and inputs applied, aiming at a sustainable system, the family farmer search a transition agroecology. However, few among them can produce or advance in agroecological transition. A reason for this difficulty may be related to biomass production in quantity and quality to ensure the agroecosystems sustainability. The family agroecosystems tend to have greater biodiversity than large farms due to a tendency to polycultures, self, family pluriactivity, among other strategies. In this local biodiversity, plants play a key role and can be considered co-products. This study aimed to characterize a unit of production and family life (UPVF) adopting management practices aimed at agroecological transition, to discuss the importance of plant biomass in this transition process and to propose alternatives to achieve the fertility system. The research was developed at Iperó in Ipanema Farm settlement in the State of Sao Paulo. The UPVF studied occupies a plot of eight hectares and is divided into seven sectors of production. The family with whom this work was developed live in the settlement since 1992. The research aimed to detail the system features and the complexity of relationships in order to describe and analyze a case study setting. It was found that the biomass produced in UPVF did not meet the nutritional demand of the main sector of commercial product, the banana orchard. The proposed redesign sought to ally virtuous experiences and scenic beauty, attractive for humans. Thus, the UPVF redesign aimed at promoting the cradle areas of fertility, assisted in the production of plant biomass in abundance and quality (diversity), preferably in well accessible, as the surrounding residences, places of daily traffic and nearby areas containment of animals. Thus, it is expected to 16 contribute to the sense of pride in the family for the successful transformation of the local landscape and the awareness of what it represents. / Muitos agricultores familiares consideram a Agroecologia a base para se produzir de forma sustentável. Com base nos princípios agroecológicos, alguns deles alteram seus sistemas produtivos, modificam os cultivos e os insumos aplicados. Entretanto, poucos conseguem produzir ou avançar no sentido de obter uma produção sustentável, em termos ambientais e econômicos. Entre os possíveis fatores que dificultam essa transição agroecológica constata-se a dificuldade para produzir biomassa em quantidade e qualidade que garanta a sustentabilidade desses agroecossistemas. Os agroecossistemas familiares tendem a apresentar maior biodiversidade em relação às grandes propriedades rurais em função da tendência aos policultivos, autoconsumo, pluriatividade familiar, entre outras estratégias. Dentro dessa biodiversidade local, os vegetais desempenham um papel fundamental e podem ser considerados coprodutos da unidade produtiva. Esta pesquisa teve por objetivos caracterizar uma unidade de produção e vida familiar (UPVF) que adota práticas de manejo visando a transição agroecológica e propor alternativas de manejo para aumentar a produção de biomassa vegetal nesse processo de transição. A pesquisa se desenvolveu em Iperó, no assentamento Fazenda Ipanema, no Estado de São Paulo. A UPVF estudada ocupa um lote de oito hectares e está dividida em sete setores de produção. A família com quem se desenvolveu este trabalho vive no assentamento desde 1992. A pesquisa buscou detalhar as especificidades do sistema e a complexidade das relações, de forma a descrever e analisar a UPVF escolhida, estabelecendo um estudo de caso. Constatou-se que a biomassa produzida na UPVF não atendeu à demanda nutricional do principal setor de produção comercial do lote, o pomar de bananeiras. O redesenho proposto buscou aliar experiências bem sucedidas e beleza paisagística, um 14 atrativo para os seres humanos. Assim, o redesenho da UPVF teve por meta favorecer as áreas berço de fertilidade, apoiadas na produção de biomassa vegetal em abundância e qualidade (diversidade), de preferência, em locais bem acessíveis, como o entorno das residências, locais de trânsito diário e proximidades das áreas de confinamento dos animais. Dessa forma, espera-se contribuir para o sentimento de orgulho na família pelo êxito na transformação da paisagem local e a consciência do que ela representa.

Made available in DSpace on 2016-04-26T19:39:30Z (GMT). No. of bitstreams: 1 Tese Doutorado - Marco Antonio de Almeida Leal.pdf: 1243520 bytes, checksum: b9888e8db72503bb47296e545d7a86b0 (MD5) Previous issue date: 2006-02-16 / The demand for organic fertilizers in Brazil is increasing, mainly in the South and Southeastern regions. The composting is a technique that can be used to increase the availability and the quality of organic fertilizers. This research aimed to study the usage of the composting of legumes and Napier grass (Pennisetum purpureum) as substitutes for cattle and poultry manure, traditional organic fertilizers used in the vegetables production. Featuring in Chapter I, the objective of the study was to determine the time of planting, and the age of cutting, which were more adequate for production of mass and accumulation o N in the Canavalia ensiformis e Crotalaria juncea. These species were chosen due to their high potential for biomass production, uniform seedling, upright growth, and determined growing pattern, which turn easy the handling of harvesting, and have no problems when cultivated in rotation systems with commercial crops. In Chapter II different conditions of composting and diverse proportions of the raw materials were studied, having as reference the mixture of Crotalaria (Crotalaria juncea) and Napier grass. The resulting composts were tested and the results are discussed on Chapter III. The composts were used as substrate for the production of vegetables seedlings and bed fertilizer in an organic system production of lettuce, beetroot and tomato. The speed of N release from the composts was also evaluated. The results indicate the Crotalaria as the most promising legume specie. It was observed that it is possible to obtain composts with high N levels by using only Crotalaria or mixed with Napier grass, without the need of inoculation or other additives. The composts obtained with these materials may substitute the commercial substrate Plantmax HT in the production of vegetables seedlings, and the cattle manure as bed fertilizers in the production of organically grown vegetables. / ? crescente a demanda por fertilizantes org?nicos no Brasil, principalmente nas regi?es Sul e Sudeste. A compostagem ? uma t?cnica que pode ser utilizada para aumentar a disponibilidade e a qualidade dos fertilizantes org?nicos. Este trabalho teve como objetivo estudar a utiliza??o da compostagem de palhada de leguminosas e capim Napier (Pennisetum purpureum) para obter substitutos para o esterco bovino e a cama de avi?rio, fertilizantes org?nicos tradicionalmente utilizados na produ??o de hortali?as. Nos experimentos apresentados no Cap?tulo I, buscou-se determinar a ?poca de plantio e a idade de corte mais adequadas para a produ??o de massa e acumula??o de N para Feij?o de Porco (Canavalia ensiformis) e Crotalaria (Crotalaria juncea), esp?cies escolhidas devido ao alto potencial de produ??o de massa, germina??o uniforme, porte ereto e h?bito de crescimento determinado, o que facilita o seu manejo de corte e n?o causa problemas quando cultivadas em sistemas de rota??o com culturas comerciais. No Cap?tulo II estudou-se diferentes condi??es de compostagem e diversas propor??es de mat?ria prima, tendo como base a mistura de Crotalaria e capim Napier. Os compostos obtidos foram testados no Cap?tulo III, sendo utilizados como substratos para a produ??o de mudas de hortali?as e como adubo org?nico de plantio para a produ??o de alface, beterraba e tomate em sistema org?nico. Avaliou-se tamb?m a velocidade de disponibiliza??o de N destes compostos. Os resultados obtidos indicam a Crotalaria como a leguminosa mais promissora para obten??o de massa e acumula??o de N. Observou-se que ? poss?vel a obten??o de compostos com elevados teores de N utilizando-se Crotalaria pura ou misturada com capim Napier, sem a necessidade de inoculantes ou outros aditivos. Compostos obtidos com estes materiais podem substituir o substrato comercial Plantmax HT na produ??o de mudas de hortali?as e tamb?m podem substituir o esterco bovino como adubo de cova na produ??o de hortali?as em sistemas de produ??o org?nicos.

Du fait de la réduction de l'usage des produits phytosanitaires, les bioagresseurs du sol, notamment les champignons Sclerotinia et les nématodes à galles Meloidogyne, sont de plus en plus préoccupants en maraîchage sous abri. Des techniques alternatives existent, mais leurs efficacités partielles et variables nécessitent la recherche de nouvelles stratégies pour leur gestion.Cette étude vise à déterminer l'intérêt de combiner deux techniques, la solarisation et l'engrais vert (Sorgho sudanense) et les influences des successions culturales et des fréquences d'utilisation de ces techniques sur leurs efficacités.Pour cela, un dispositif en parcelles de producteurs a permis de suivre l'évolution des incidences et sévérités de Sclerotinia et Meloidogyne dans différents systèmes de culture.Les effets des cultures de melon sont prédominants sur ceux des techniques alternatives, de façon opposée pour ces deux bioagresseurs. Les successions incluant du melon favorisent les plus fortes attaques de Meloidogyne alors qu'elles réduisent celles de Sclerotinia. Pour ce pathogène, l'utilisation de solarisation tous les ans ou un an sur deux en combinaison avec l'engrais vert en assure le contrôle le plus efficace. Par contre, la culture de melon étant très sensible à Meloidogyne, elle masque les effets des techniques alternatives.Des propositions d'amélioration de systèmes de culture, basées sur la modification des fréquences de culture du melon et sur l'optimisation de l'usage des techniques alternatives, ont été faites pour la gestion commune de Sclerotinia et Meloidogyne.Ces résultats montrent les interactions entre les différentes pratiques culturales utilisées sur une parcelle et l'intérêt des études agronomiques systémiques. De plus, les effets opposés observés d'un même système de culture soulignent l'intérêt d'études multi-bioagresseurs, pour ne pas faire de propositions qui résolvent un problème mais en aggravent d'autres. / In the current context of the reduction of pesticide use, soilborne pests and diseases, and especially the fungi Sclerotinia and the root-knot nematodes Meloidogyne, become more and more worrying in vegetable production under shelter in Southern France. Alternative techniques exist, but their partial and varying efficiencies require the search for new strategies of management of these pests and diseases fit for producers.Therefore, the aim of this study is to determine the benefit of combinations of two techniques, soil solarisation and green manure (Sorghum sudanense). It is also to determine the influences of crop successions and frequences of these techniques on their individual efficiencies.To this effect, a setup of producers' plots has been designed. The spatiotemporal evolution of incidences and severities of Sclerotinia and Meloidogyne in several cropping systems has been observed on this setup.The presence of a melon crop has a major influence on the efficiency of the alternative techniques. Opposite effects for the two considered pests and diseases appeared. Crops successions with melon are most favourable to highest infestations of Meloidogyne whereas, Sclerotinia infections are reduced. For this pathogen, a solarisation every year or every two years ensures the most effective control. On the contrary, in the case of Meloidogyne, the melon crop is very sensitive to this pest, a characteristic that masks the positive effects of alternative techniques.

Submitted by Celso Magalhaes (celsomagalhaes@ufrrj.br) on 2018-09-11T19:30:41Z No. of bitstreams: 1 2017 - Marcius Nei Zanin Cesar.pdf: 3447328 bytes, checksum: 098490a3674208d8609db17b18d3c285 (MD5) / Made available in DSpace on 2018-09-11T19:30:41Z (GMT). No. of bitstreams: 1 2017 - Marcius Nei Zanin Cesar.pdf: 3447328 bytes, checksum: 098490a3674208d8609db17b18d3c285 (MD5) Previous issue date: 2009-04-30 / Cap. I The aim of this work is to evaluate the agronomic behavior of different legume species under cerrado conditions in Mato Grosso do Sul. Seven experiments were carried out, all of them in the experimental field of the (Ag?ncia de Desenvolvimento Agr?rio e Extens?o Rural de MS), (Agency of rural development and extension of MS). Two of these experiments referred to the performance of legumes evaluation. The first experiment was carried out during the Spring- Summer period, and the second one during the Fall- Winter period. The treatments were constituted by the legume species (Crotalaria juncea, Crotalaria ochroleuca, Crotalaria mucronata, Crotalaria reviflora, Mucuna pruriens, Mucuna aterrima, Cajanus cajan (L.) Millsp Cv Fava larga and Cv IAPAR Arat? 43 an?o, Canavalia ensiformes and Canavalia brasiliensis). The third experiment was carried out to determine the dry phytomass decomposition rate and the nitrogen release of the species that were evaluated; this happened during the Fall-Winter period, and the treatments were the mulching of the legumes cited above, except C. breviflora, which was severely attacked by Fusarium sp. The experimental design adopted was randomized blocks, with eleven treatments and nine harvest dates disposed with four replicates. The forth and the fifth experiments were carried out in the subsequent year, their aim was qualifying the Biological Nitrogen Fixation (hereinafter called BNF) and determining the isotope discrimination value ?B value?; their treatments were seven legume species previously selected due to their performances on the former experimental actions and three checks, Brachiaria decumbens, Helianthus annuus, and Zea mays cv BR 106, disposed in randomized blocks with four replicates. The sixth and the seventh experiments were carried out to evaluate the performance of the cabbage cv Astrus under organic management in no-tillage system. The treatments of the sixth experiment were maize-velvet bean intercrop. The later was sown in five different times after maize germination, mucuna alone, maize alone, spontaneous vegetation, and cultivation with conventional tillage of the soil. The treatments of the seventh experiment were maize intercropped with Crotalaria juncea, the latter was slashed, slashed and pruned, maize with basic fertilizer, maize with basic and dressing fertilizers, crotalaria alone, maize alone, spontaneous vegetation, and cultivation with conventional tillage of the soil. The experimental design adopted for both experiments was randomized blocks. The evaluation of the aerial phytomass production was determined when the legume species flowered and when the non-legume ones underwent the grain filling process. The quantification of BNF and the determination of the B value were estimated by using natural abundance 15N and the 15N dilution technique. Functional growth analyses were also carried out as well as soil cover rates, digestion time of the plant tissues, and the phytosociology were determined. On the sixth and seventh experiments the green manure contributions on the agronomic behavior of the cabbage cultivated in no-tillage system under organic management were evaluated. The results obtained have demonstrated the viability for the cultivations of these legume species at the Cerrado Biome, with the contribution of the BNF varying between 75 and 85% of the nitrogen found in the plant tissue originating from the air. They have also demonstrated the viability of using C. juncea and velvet bean when both are intercropped with maize in the mulching formation to the organic cultivation of the cabbage in no-tillage system Cap. II Two experiments were carried out to evaluate the agronomic behavior of legume species in which several components of plant growth were evaluated, such as aerial phytomass production, soil cover rate, seed production, besides phytosociology and in situ decomposition rate under cerrado conditions in Mato Grosso do Sul in two periods of the year. One experiment was carried out during the Spring-Summer period and the other one was carried out during the Fall-Winter period. Both experiments were carried out at the Centro de Pesquisa da Ag?ncia de Desenvolvimento Rural e Extens?o Rural de Mato Grosso do Sul (Mato Grosso do Sul Research center of the Agency of rural development and extension), in Campo Grande ? MS. The experimental design adopted for both was randomized blocks, formed by eleven treatments made up by the species C. juncea, C. ochroleuca, C. mucronata, C. spectabilis, C. breviflora, Mucuna aterrima, Mucuna pruriens, Canavalia brasiliensis, Canavalia ensiformis, Cajanus Cajans cv ?IAPAR an?o?, and Cajanus Cajans cv. giant broad bean. The agronomic behavior of the species that were studied was evaluated by the analysis of the stem and the leaf separately. It was observed that the aerial phytomass productions differed significantly with the species of the genus Crotalaria, showing the best results. Crotalaria juncea stands out with 14.16 Mg ha-1, followed by the Cajanus cajan cv. Fava larga with 11.58 Mg ha-1; there were no significant differences among the species of prostrate habit, mucunas and Brazilian jackbean (Canavalia brasiliensis). The later obtained 3.56 Mg ha-1 and the former did 2.85 Mg ha-1. Regarding seed production, the best performances were obtained during the Fall-Winter period for all legume species, except jack bean and feij?o-bravo (Capparis flexuosa), both obtained similar performances on the two periods of sowing, probably because they might be more tolerant to the drought stress. Regarding the decomposition rate, the results have revealed that the decomposition constants and the residue half-lives had different behaviors on the species that were studied; the Crotalaria species obtained higher decomposition rates when compared to the other species, differentiated behaviors were also noticed on the stem and on the leaf. The C. juncea, jack bean, and the two species of mucuna obtained higher soil cover rate, which reflected a higher suppression of spontaneous plants Cap. III Two experiments related to the quantification of BNF and the determination of the isotope discrimination, ?B value?, in legume species previously selected were simultaneously carried out in the experimental field of the AGRAER-MS, in Campo Grande-MS, during the Spring/Summer period in the 2005/2006 year of production. The experimental design adopted was randomized blocks, formed by ten treatments made up by the species C. juncea, C. ochroleuca, C. mucronata, C. spectabilis, velvet bean, Brazilian jackbean, and Pigeon pea; there have been also, as checks, Sunflower, Maize, and Brachiaria species. The aerial phytomass productions were determined when each legume species flowered and when the non-legume ones underwent the grain filling process. With the samples of legumes and check plants, the quantities of N and the BNF were estimated by using the 15N dilution technique. Afterwards, when the BNF values were known, they were applied to the equation used in natural abundance 15N with the aim of estimating the B value. Regarding the aerial phytomass production, the Pigeon pea had the best performance, followed by the C. ochroleuca, reaching averages of 16.24 Mg ha-1 against 14.44 Mg ha-1. The legume species behaved similarly to the amount of accumulated nitrogen; the Pigeon pea, C. ohcroleuca, and C. mucronata reached values of 346.57 kg ha-1, 333.25 kg ha-1, and 277.35 kg ha- 1 respectively, and they deserve a distinction. Regarding the %BNF, it was observed that the 15N dilution technique could not be applied in all the species that were studied since the cycle of most legumes species was different from the checks; in this way, the checks were not appropriate because the technique demands that legumes and checks grow simultaneously and under the same conditions. However, to the varieties which were more precocious that the checks, the BNF value must be at least between 73 to 87%. Just on the specie C. mucronata it was possible to estimate the BNF and the B value with the rigor that the applied isotopic methodologies demand. The B value of this specie was -3.69. Cap. IV The aim of this study is to evaluate the agronomic behavior of the cabbage in no-tillage system under organic management and the contribution of the prior cultivation of two legumes with different growing habits intercropping with maize in the mulching formation. Both experiments were carried out in the experimental field of AGRAER-MS, in Campo Grande-MS. The first experiment was the maize-C. juncea intercrop, the latter was managed, slashed, pruned, and slashed afterwards; besides the cultivation of single maize, single C. juncea, cultivation with conventional tillage of the soil with and without fertilization with equivalent amounts of 100 Kg N ha-1 at planting and sidressed 30 days after the maize cultivation, making up eight treatments with four replications in randomized blocks. The dry matter productions in the aerial part of the cover crops and the spontaneous vegetation were evaluated. Agronomic characteristics that were evaluated on the cabbage: productivity, commercial standard, fresh and dry weight, besides the dry phytomass of the prior cultivation. On this experiment it was possible to verify better yields regarding the fresh weight and head diameter when we used single, pruned C. juncea maize with basic fertilizer, and maize with base and dressing fertilizers, reaching a fresh weight over 1.0 Kg and heads diameter over 10 cm. Regarding maize and cabbage productivity, they were not influenced by the different kinds of intercrop systems; there were no significant statistic difference of treatments, which also reflected on the dry matter production of the prior cultivations. On the second experiment, the experimental design which was adopted was randomized blocks, with nine treatments and four replicates. The treatments were: maize-velvet bean intercrop, the later was planted in five different times: after the maize germination, maize alone, mucuna alone, cultivation with conventional tillage of the soil, and fallow with spontaneous vegetation, making up a total number of nine treatments. The parameters that were evaluated were similar to the ones of the former experiment.The cabbage production showed the most promising yield 2.06 Kg of head average weight and when cultivated as a sequential crop to the maize-velvet bean intercrop sown 15 days after the maize germination, differing significantly from the other treatments. When we analyzed the maize productivities, we noticed fall of productivity around 29% when it was intercropped with velvet bean at 15 and 30 days after its germination when it was compared to the other prior cultivations in which the intercrop system was used. / Cap. I O presente trabalho teve como finalidade avaliar o comportamento agron?mico de diferentes esp?cies de leguminosas nas condi??es do cerrado de Mato Grosso do Sul. Foram conduzidos sete experimentos, todos no campo experimental da Ag?ncia de Desenvolvimento Agr?rio e Extens?o Rural de MS, sendo que dois deles foram referentes ? avalia??o do desempenho das leguminosas. O primeiro foi instalado no per?odo de primavera-ver?o e o segundo no outonoinverno. Os tratamentos foram constitu?dos das esp?cies de leguminosas Crotal?ria juncea, Crotal?ria ochroleuca, Crotal?ria mucronata, Crotal?ria reviflora, Mucuna pruriens, Mucuna aterrima, Cajanus cajan (L.) Millsp cv Fava larga e Cv IAPAR Arat? 43 an?o, Canavalia ensiformes e Canavalia brasiliensis. O terceiro experimento foi realizado para determinar a taxa de decomposi??o da fitomassa seca e libera??o de nitrog?nio das esp?cies avaliadas, realizado no per?odo de outono-inverno, com os tratamentos constituindo-se da palhada das leguminosas descrita acima, exceto C. breviflora, pois a leguminosa sofreu ataque severo de Fusarium sp. O delineamento experimental foi em blocos ao acaso, com onze tratamentos e nove ?pocas de coleta distribu?dos em quatro repeti??es. O quarto e o quinto experimentos foram realizados no ano subsequente e tiveram como finalidade quantificar a Fixa??o Biol?gica de Nitrog?nio (FBN) e determinar o valor de discrimina??o isot?pica ?Valor B?, tendo como tratamentos sete esp?cies de leguminosas previamente selecionadas pelos seus desempenhos nas a??es experimentais anteriores e tr?s testemunhas, Brachiaria decumbens, Helianthus annuus e Zea mays cv BR 106, dispostos em blocos ao acaso com quatro repeti??es. O sexto e o s?timo experimentos foram conduzidos para avaliar o desempenho do repolho cv Astrus sob manejo org?nico em sistema plantio direto, sendo que o sexto experimento teve como tratamentos cons?rcio milho x mucuna cinza, sendo esta semeada em cinco ?pocas diferentes, ap?s germina??o do milho, mucuna em monocultivo, milho em monocultivo, vegeta??o espont?nea e cultivo com preparo convencional do solo. O s?timo experimento teve como tratamentos milho consorciado com Crotal?ria juncea, sendo esta ro?ada, ro?ada e podada, milho com aduba??o de base, milho com aduba??o de base e cobertura, crotal?ria em monocultivo, milho em monocultivo, vegeta??o espont?nea e cultivo com preparo convencional do solo. O delineamento experimental adotado em ambos os experimentos foi o de blocos ao acaso. A avalia??o da produ??o de fitomassa a?rea foi determinada por ocasi?o do florescimento para as esp?cies de leguminosas e de enchimento de gr?os para as n?o-leguminosas. A quantifica??o da FBN e determina??o do valor ?B? foram estimadas utilizando-se a t?cnica de abund?ncia natural 15N e da dilui??o isot?pica de 15N. Foram tamb?m realizadas an?lises funcionais de crescimento, bem como determinadas as taxas de cobertura do solo, tempo de decomposi??o dos tecidos vegetais e a fitossociologia. No sexto e no s?timo experimentos, foram avaliadas as contribui??es da aduba??o verde no desempenho agron?mico do repolho cultivado em sistema de plantio direto, sob manejo org?nico. Os resultados obtidos demonstraram a viabilidade do cultivo destas leguminosas no bioma cerrado, com a contribui??o da FBN, variando entre 75 e 85% do nitrog?nio encontrado no tecido vegetal proveniente do ar. Tamb?m, demonstraram a viabilidade do uso da C. juncea e M. cinza quando cultivadas em cons?rcio com milho para obten??o de palhada ao cultivo org?nico do repolho em sistema plantio direto. Cap. II Dois experimentos foram conduzidos para avaliar o comportamento agron?mico de esp?cies de leguminosas, onde foram avaliados diferentes componentes do crescimento vegetal, como produ??o fitomassa a?rea, taxa de cobertura de solo, produ??o de sementes, al?m da fitossociologia e taxa de decomposi??o ?in situ?, nas condi??es do cerrado de Mato Grosso do Sul, em duas ?pocas do ano. Os experimentos foram conduzidos no Centro de Pesquisa da Ag?ncia de Desenvolvimento Agr?rio e Extens?o Rural de Mato Grosso do Sul, localizado em Campo Grande - MS, sendo um no per?odo de primavera-ver?o e outro no outono-inverno. Em ambos, o delineamento experimental adotado foi o de blocos ao acaso, formado de onze tratamentos constitu?dos das esp?cies C. juncea, C. ochroleuca, C. mucronata, C. spectabilis, C. breviflora, Mucuna aterrima, Mucuna pruriens, Canavalia brasiliensis, Canavalia ensiformis, Cajanus Cajans cv. IAPAR an?o e Cajanus Cajans cv. fava larga gigante. O comportamento agron?mico das esp?cies estudadas foi avaliado analisando-se separadamente haste e folha. Observou-se que as produ??es de fitomassa a?rea diferiram de forma significativa com as esp?cies do g?nero crotal?ria, obtendo-se melhores desempenhos. Destacam-se a Crotal?ria juncea com 14,16 Mg ha-1, seguida do Guandu cv fava-larga com 11,58 Mg ha-1; entre as esp?cies de h?bito prostrado, n?o houve diferen?as significativas, mucunas e o feij?o-bravo-do Cear?, sendo que esse obteve 3,56 Mg ha-1 contra 2,85 Mg ha-1 da M. preta. Com rela??o ? produ??o de sementes, os melhores desempenhos foram obtidos no per?odo de outono-inverno para todas as leguminosas, com exce??o do feij?o-de-porco e feij?o-bravo, que obtiveram desempenhos semelhantes nas duas ?pocas de semeadura, provavelmente, por serem mais tolerantes ao estresse h?drico. No tocante ? taxa de decomposi??o, os resultados revelaram que as constantes de decomposi??o e tempo de meia-vida tiveram comportamentos diferentes para as esp?cies estudadas, com esp?cies de crotal?ria obtendo maiores velocidades de decomposi??o quando comparadas ?s demais esp?cies, notou-se tamb?m comportamentos diferenciados para haste e folha. A C. juncea, feij?o de porco e as duas esp?cies de mucuna obtiveram maior taxa de cobertura de solo, o que refletiu em uma maior supress?o da vegeta??o de ocorr?ncia espont?nea Cap III Foram conduzidos simultaneamente dois experimentos relacionados ? quantifica??o da FBN e determina??o do valor de discrimina??o isot?pica, valor ?B?, em esp?cies de leguminosas previamente selecionadas. Os experimentos foram conduzidos no campo experimental da AGRAER-MS, localizado em Campo Grande-MS, no per?odo de primavera-ver?o, no ano agr?cola 2005/06. O delineamento estat?stico utilizado foi o de blocos ao acaso, constitu?dos de dez tratamentos, sendo este compostos pelas esp?cies C. juncea, C. ochroleuca, C. mucronata, C. spectabilis, Mucuna cinza, Feij?o-bravo-do-cear? e Guandu fava larga; e como testemunhas as esp?cies Girassol, Milho e Braqui?ria. Por ocasi?o do florescimento de cada esp?cie de leguminosa e enchimento de gr?os das n?o-leguminosas, foram determinadas as produ??es de fitomassa a?rea. A partir das amostras de leguminosas e plantas testemunhas, estimaram-se as quantidades de N e a FBN, para tanto usando a t?cnica de dilui??o isot?pica de 15N . Posteriormente, conhecendo-se os valores de FBN, aplicou-se aos mesmos a equa??o utilizada na t?cnica de abund?ncia natural de 15N com a finalidade de estimar o valor B. Com rela??o ? produ??o de fitomassa a?rea, o Guandu fava larga obteve melhor desempenho seguido da C. ochroleuca, atingindo m?dias de 16,24 Mg ha -1 contra 14,44 Mg ha-1. Para a quantidade de nitrog?nio acumulada as esp?cies de leguminosas se comportaram de maneira semelhante, com destaque para o Guandu fava larga, C. ohcroleuca e C. Mucronata, atingido valores de 346,57 kg ha-1, 333,25 kg ha-1 e 277,35 kg ha-1 respectivamente. No tocante ? %FBN, observou-se que a t?cnica de dilui??o isot?pica de 15N n?o poderia ser aplicada para todas as esp?cies estudadas, uma vez que a maioria das esp?cies de leguminosas teve ciclo diferenciado das testemunhas, desta forma, as testemunhas n?o foram apropriadas, visto que a t?cnica exige que tanto as leguminosas como as testemunhas cres?am nas mesmas condi??es e de forma simult?nea. Contudo, para as variedades mais precoces que as testemunhas, o valor de FBN deve estar no m?nimo entre 73 a 87%. Somente na esp?cie C. Mucronata, foi poss?vel estimar a FBN e o valor B com o rigor que exigem as metodologias isot?picas aplicadas. O valor B para esta esp?cie foi de -3,69. Cap. IV O presente estudo teve o objetivo de avaliar o desempenho agron?mico do repolho em sistema plantio direto, sob manejo org?nico, e a contribui??o do pr?-cultivo de duas leguminosas de h?bitos de crescimento distintos em cons?rcio com milho, na forma??o de palhada. Ambos experimentos foram implantados no Campo Experimental da AGRAER, em Campo Grande-MS. O primeiro experimento consistiu no cons?rcio entre milho e C. juncea, sendo esta manejada, somente com ro?ada (taratamento 6), podada e posteriormente ro?ada (tratamento 5), al?m do cultivo do milho solteiro, C. juncea solteira, cultivo com preparo convencional do solo, com aus?ncia e presen?a de aduba??o, em quantidades equivalentes a 100 Kg N ha-1 no plantio e em cobertura 30 dias ap?s plantio do milho, perfazendo oito tratamentos com quatro repeti??es, dispostos em blocos ao acaso. Avaliaram-se as produ??es de mat?ria seca na parte a?rea das plantas de cobertura e da vegeta??o espont?nea. As caracter?sticas agron?micas avaliadas no repolho foram: produtividade, padr?o comercial, peso fresco e seco, al?m da fitomassa seca do pr?-cultivo. Neste experimento, verificaram-se melhores rendimentos quanto ao peso m?dio e di?metro da cabe?a quando se utilizaram C. juncea solteira, C.juncea ro?ada, milho com aduba??o de base e milho com aduba??o de base e cobertura, alcan?ando peso m?dio acima de 1,0 kg e di?metro das cabe?as acima de 10 cm. Quanto ? produtividade do milho e do repolho, estes n?o foram influenciados pelos diferentes tipos de cons?rcios, n?o havendo diferen?a estat?stica significativa entre os tratamentos, o que refletiu tamb?m na produ??o de mat?ria seca dos pr?-cultivos. No segundo experimento, o delineamento experimental utilizado foi o de blocos ao acaso com nove tratamentos e quatro repeti??es. Os tratamentos foram: o cons?rcio entre milho e mucuna cinza, sendo esta plantada em cinco ?pocas diferentes - ap?s a germina??o do milho, monocultivo do milho, monocultivo da mucuna, cultivo com preparo convencional do solo e pousio com vegeta??o espont?nea -, perfazendo um total de nove tratamentos. Os par?metros avaliados foram semelhantes aos do experimento anterior. A produ??o do repolho alcan?ou melhores rendimentos, 2,06 kg de peso m?dio da cabe?a; e, quando cultivado em sucess?o ao cons?rcio milho x M. Cinza, semeada aos 15 dias ap?s germina??o do milho, diferiu significativamente dos demais tratamentos. Ao se analisarem as produtividades do milho, notouse uma queda de rendimento em torno de 29% quando este foi consorciado com M. Cinza, aos 15 e 30 dias ap?s sua germina??o, ao comparar-lo aos demais pr?-cultivos utilizando-se cons?rcios