A major goal for Mongolia is to eliminate rural poverty through sustainable rural development. To accomplish this, the agricultural sector must become more profitable and sustainable. Declining crop yields can be addressed by the adoption of new technology. Barriers to introduction of new agricultural technologies were evaluated using an inter-disciplinary perspective.<p> Field research was carried out to understand the factors affecting Mongolian farmers decisions to adopt conservation farming practices. A semi-structured survey questionnaire was completed by 42 farmers and 30 extension agents and in-depth interviews were conducted with ten adopter-farmers in Mongolia. The introduction of conservation tillage was used to illustrate a technology transfer system and the challenges it poses.<p> To most of the farmers, the main advantages of this technology were reduced soil erosion, increased cost efficiency, and higher crop yields. The main disadvantages found were high investment costs, unreliable input supply, and a lack of knowledge of the technology. Factors that encourage adoption of new technologies include government financial incentives, reduced labor requirements, and increased production due to better soil and water conservation. A lack of investment capital, required inputs, and relevant knowledge were all identified as barriers for the utilization of such new technologies. In general, early adopters and non-adopters of conservation tillage differed in that the early adopters tended to have more farmland, livestock, and equipment. The field studies in Mongolia were complemented by field research trials in Canada that evaluated new technologies for weed control in conservation tillage systems.<p> One key to the successful adoption of new agriculture technologies is an effective and responsive research and extension system. Currently, for Mongolian farmers and extension agents, international projects are the main source of information with respect to new agricultural technologies. The capacity of local research and extension institutions is fairly limited. It will be important to establish better linkages among 3 researchers, extension agents, farmers, and policy makers through reorganization and strengthening of Mongolias top-down research and extension system. Meaningful farmer participation must take place at all stages of any technology transfer process.<p> Based on these principles, an interdisciplinary, inclusive, and responsive national agricultural research and extension model is proposed.

A major goal for Mongolia is to eliminate rural poverty through sustainable rural development. To accomplish this, the agricultural sector must become more profitable and sustainable. Declining crop yields can be addressed by the adoption of new technology. Barriers to introduction of new agricultural technologies were evaluated using an inter-disciplinary perspective.<p> Field research was carried out to understand the factors affecting Mongolian farmers decisions to adopt conservation farming practices. A semi-structured survey questionnaire was completed by 42 farmers and 30 extension agents and in-depth interviews were conducted with ten adopter-farmers in Mongolia. The introduction of conservation tillage was used to illustrate a technology transfer system and the challenges it poses.<p> To most of the farmers, the main advantages of this technology were reduced soil erosion, increased cost efficiency, and higher crop yields. The main disadvantages found were high investment costs, unreliable input supply, and a lack of knowledge of the technology. Factors that encourage adoption of new technologies include government financial incentives, reduced labor requirements, and increased production due to better soil and water conservation. A lack of investment capital, required inputs, and relevant knowledge were all identified as barriers for the utilization of such new technologies. In general, early adopters and non-adopters of conservation tillage differed in that the early adopters tended to have more farmland, livestock, and equipment. The field studies in Mongolia were complemented by field research trials in Canada that evaluated new technologies for weed control in conservation tillage systems.<p> One key to the successful adoption of new agriculture technologies is an effective and responsive research and extension system. Currently, for Mongolian farmers and extension agents, international projects are the main source of information with respect to new agricultural technologies. The capacity of local research and extension institutions is fairly limited. It will be important to establish better linkages among 3 researchers, extension agents, farmers, and policy makers through reorganization and strengthening of Mongolias top-down research and extension system. Meaningful farmer participation must take place at all stages of any technology transfer process.<p> Based on these principles, an interdisciplinary, inclusive, and responsive national agricultural research and extension model is proposed.

Quantitative and qualitative Soil Organic Matter (SOM) properties were observed in the soil samples of a medium-term field experiment (Cambisol ? Studena, Czech Republic) and an exact field experi?ment (Chernozem ? Gross Enzersdorf, Austria) in the year 2005 considering different soil tillage systems (conventional and minimum tillage). Except the standard parameters, soil organic matter content and quality in particulate water stable aggregates size fractions was additional determinated for Cambisol. Cambisol showed more favourable values of both quantitative and qualitative SOM parameters in minimum tillage system compared to those in conventional tillage system. SOM quality in the water stable aggregates fractions was better in minimum tillage compared to conventional tillage. Cambisol also showed that SOM in aggregates fractions is much more quality compared to SOM in the original soil samples. Chernozem showed higher values of both quantitative and qualitative SOM parameters in conventional tillage compared to those in minimum tillage but the differences are not high. It can be said that Chernozem organic matter reaction to tillage technology changes is slower and of minor rate in comparison with that of Cambisol organic matter. The results of quantitative and qualitative parameters do not conform to the generally recognised values for the Chernozem soil type.

Made available in DSpace on 2014-06-11T19:29:44Z (GMT). No. of bitstreams: 0 Previous issue date: 2006-07-28Bitstream added on 2014-06-13T18:59:27Z : No. of bitstreams: 1 celestino_jc_me_ilha.pdf: 506534 bytes, checksum: 4c97d89e0f16a317ecd11b50cf358d89 (MD5) / Universidade Estadual Paulista (UNESP) / A assimilação do nitrogênio é um processo vital que controla o crescimento e o desenvolvimento das plantas e tem efeitos marcantes sobre a fitomassa e a produtividade final das culturas. A rota de assimilação do nitrato em plantas superiores envolve dois estágios seqüenciais, conversão do nitrato a nitrito pela redutase do nitrato (NR) e nitrito a amônio, mediada pela enzima redutase do nitrito (NiR). O presente trabalho teve o objetivo de verificar a atividade da enzima NR em arroz cv. IAC 202 conduzido sob solo proveniente de áreas de sistema de plantio direto e plantio em solo escarificado, aliado a doses crescentes de nitrogênio (0, 25, 50, 75, 100 e 125 kg.ha -1 ) em dois regimes hídricos. As plantas foram cultivadas em vasos a céu aberto e as análises foram realizadas de acordo com método clássico in vivo. O delineamento experimental foi blocos casualizados, com quatro repetições. Foram feitas três análises com intervalo de sete dias entre uma e outra e estas se iniciaram sete dias após a aplicação do N em cobertura. Com base nos resultados obtidos pode-se concluir que a maior atividade da enzima está relacionada com a disponibilidade de água e ao tipo de manejo do solo (plantio direto). / The assimilation of the nitrogen is a vital process that it controls the growth and the development of the plants and it has outstanding effects on the biomass and the final productivity of the crops. The pathway of assimilation of the nitrate in plants involves two sequential stage, one is reduction the nitrate to nitrite mediated by the nitrate reductase (NR) and reduction the nitrite to ammonium mediated by the enzyme nitrite reductase (NiR). In the present work objetivated to verify the enzyme NR activity in rice cv. IAC 202 plants cultivated in two conditions of handling of the soil, no-tillage and minimum tillage, and doses of Nitrogen (0, 25, 50, 75, 100 and 125 kg.ha -1 ) on irrigation and without irrigation. The plants were cultivated in vases to open sky and the analyses were accomplished in agreement with method classic alive in. The experimental design was randomized blocks, with four repetitions. It was made three evaluations in the interval of seven days; the analysis began seven days after the N application on covering. The largest activity of the enzyme is related with readiness of water and to the soil cultivation with the better performance was observed in no-tillage system.

Orientador: Kuniko Iwamoto Haga / Banca: Elizabeth Orika Ono / Banca: Leandro Ferreira de Aguiar / Resumo: A assimilação do nitrogênio é um processo vital que controla o crescimento e o desenvolvimento das plantas e tem efeitos marcantes sobre a fitomassa e a produtividade final das culturas. A rota de assimilação do nitrato em plantas superiores envolve dois estágios seqüenciais, conversão do nitrato a nitrito pela redutase do nitrato (NR) e nitrito a amônio, mediada pela enzima redutase do nitrito (NiR). O presente trabalho teve o objetivo de verificar a atividade da enzima NR em arroz cv. IAC 202 conduzido sob solo proveniente de áreas de sistema de plantio direto e plantio em solo escarificado, aliado a doses crescentes de nitrogênio (0, 25, 50, 75, 100 e 125 kg.ha -1 ) em dois regimes hídricos. As plantas foram cultivadas em vasos a céu aberto e as análises foram realizadas de acordo com método clássico in vivo. O delineamento experimental foi blocos casualizados, com quatro repetições. Foram feitas três análises com intervalo de sete dias entre uma e outra e estas se iniciaram sete dias após a aplicação do N em cobertura. Com base nos resultados obtidos pode-se concluir que a maior atividade da enzima está relacionada com a disponibilidade de água e ao tipo de manejo do solo (plantio direto). / Abstract: The assimilation of the nitrogen is a vital process that it controls the growth and the development of the plants and it has outstanding effects on the biomass and the final productivity of the crops. The pathway of assimilation of the nitrate in plants involves two sequential stage, one is reduction the nitrate to nitrite mediated by the nitrate reductase (NR) and reduction the nitrite to ammonium mediated by the enzyme nitrite reductase (NiR). In the present work objetivated to verify the enzyme NR activity in rice cv. IAC 202 plants cultivated in two conditions of handling of the soil, no-tillage and minimum tillage, and doses of Nitrogen (0, 25, 50, 75, 100 and 125 kg.ha -1 ) on irrigation and without irrigation. The plants were cultivated in vases to open sky and the analyses were accomplished in agreement with method classic alive in. The experimental design was randomized blocks, with four repetitions. It was made three evaluations in the interval of seven days; the analysis began seven days after the N application on covering. The largest activity of the enzyme is related with readiness of water and to the soil cultivation with the better performance was observed in no-tillage system. / Mestre

Agriculture is one of the main sources of phosphorous and nitrogen (P and N) contributing to cultural eutrophication of freshwater lakes and estuaries. In cold regions, the effects of agricultural management practices used to mitigate the runoff loss of these nutrients remain uncertain. In particular, the use of forage crops and minimum tillage, have not reduced some forms of P and N in runoff to streams, in part, as a result of freeze-thaw induced losses of mobile P and N from forages and crop residues. The purpose of this research is to improve the current understanding of the controls on P and N loss from Canadian Prairie fields to ultimately aid in the development and evaluation of beneficial agricultural management practices that perform predictably in cold regions. This study aims to provide new insights into the effects of cold regions hydrological processes on runoff quality through the development and application of a novel inductive - deductive modelling approach. Runoff flowpaths resulting from the three infiltration regimes identified for frozen soils (Granger et al., 1984) are hypothesized to impact the chemistry of field scale meltwater runoff by varying meltwater interaction with agricultural soils and vegetation. Hydrochemistry data from six intensively monitored minimum tillage and forage cropped fields in South Tobacco Creek, Manitoba were used to develop a nutrient model to integrate with a physics-based hydrological modelling platform that can represent the frozen soil infiltration regimes, in addition to other important cold region hydrological processes. The inductive development of a nutrient model, integrated with a deductive physics-based hydrological platform, enabled the modelling of meltwater flowpaths and freeze-thaw induced losses from vegetation. Further testing of the developed model and field experimentation are required to test the hypothesis that runoff generated over a basal ice layer eliminates the transfer of soil nutrients to runoff. Comparison of predicted and observed field scale runoff concentrations and masses suggest that this method of inductive-deductive model development has potential to predict the performance of agricultural management practices in cold regions.

Diss. (sammanfattning) Uppsala : Sveriges lantbruksuniv. / Härtill 4 uppsatser.

This diplom thesis deals with the evaluation of quality machines work for soil cultivation used in minimalization soil cultivation technology and weed control in cereal crops. The machines were evaluated for incorporation of harvest residues, uniformity of depth and size of lumps. It was further performed an economic evaluation of selected cost per operation soil cultivation. In order to monitor the development of weeds was based small-plot experiment, where was monitored representation of individual weed species and the effectiveness of selected herbicide.

Submitted by PAULO ROBERTO DE SOUSA JÚNIOR null (paulo_pexe@yahoo.com.br) on 2016-09-05T00:01:58Z No. of bitstreams: 1 Tese mestrado-Paulo Roberto de Sousa Junior (Produção Vegetal) v18.pdf: 1339589 bytes, checksum: 6577d94ec4da539c53ad11caabc30271 (MD5) / Approved for entry into archive by Juliano Benedito Ferreira (julianoferreira@reitoria.unesp.br) on 2016-09-06T20:00:06Z (GMT) No. of bitstreams: 1 sousajunior_pr_me_jabo.pdf: 1339589 bytes, checksum: 6577d94ec4da539c53ad11caabc30271 (MD5) / Made available in DSpace on 2016-09-06T20:00:06Z (GMT). No. of bitstreams: 1 sousajunior_pr_me_jabo.pdf: 1339589 bytes, checksum: 6577d94ec4da539c53ad11caabc30271 (MD5) Previous issue date: 2016-07-08 / Levando em consideração que há uma grande polêmica quanto à forma mais eficiente de aplicação do fósforo nos solos tropicais brasileiros, o presente trabalho sugere a forma mais eficiente de aplicação e fornecimento desse elemento para a produção de cana-de-açúcar em um ambiente de médio potencial produtivo, enfatizando modos de aplicação e doses adequadas à maior disponibilização deste nutriente na solução do solo. Para avaliar os efeitos de incorporação do fósforo e dos outros corretivos, utilizaram-se dois manejos de solo: o preparo convencional e o cultivo mínimo. A pesquisa foi fundamentada em duas hipóteses: I) A aplicação de parte do fósforo em área total e a outra parte no fundo do sulco, em solos de textura média, proporcionam maior aproveitamento do fósforo e outros nutrientes a curto e longo prazo. II) A incorporação do fósforo e dos outros corretivos de solo proporcionam uma melhor condição para o desenvolvimento do sistema radicular. O delineamento experimental utilizado foi o de blocos inteiramente casualizados com parcelas subdivididas em: tratamento principal, manejo do solo, preparo convencional e cultivo mínimo, tratamento secundário, dose área total 0; 100; 200 kg.ha-1 P2O5, tratamento terciário, dose no sulco 0; 90; 180 kg.ha-¹ P2O5. Foram avaliados os parâmetros químicos do solo, produtividade de colmos e açúcar, tecnológicos e exportação de nutrientes. O programa estatístico utilizado foi o AgroEstat – Sistema para Análises Estatísticas de ensaios agronômicos. Os resultados mostraram que o cultivo mínimo proporcionou uma maior concentração do fósforo na camada superficial em relação ao preparo convencional e o excesso de fósforo causou uma diminuição na qualidade tecnológica e na produção de açúcar. / Taking into consideration the polemics involved on which is the most efficient phosphorus application method in Brazilian tropical soils, the present research suggests an efficient phosphorus application method in sugarcane production in an environment of medium potential, emphasizing phosphorus application methods and rates, aiming the best availability of this element in the soil solution. In order to evaluate the phosphorus incorporation effects and other soil correction chemicals, two soil managements were adopted; the conventional and the minimum tillage. Therefore, this research were based on two hypothesis: I) the application of part of the phosphorus over the soil and other part in the sugarcane furrow, in sandy soils, allowed higher phosphorus and other nutrients utilization. II) The phosphorus incorporation and incorporation of other element allowed better sugarcane root systems development. The experimental design used was completely randomized block design, with split-split plot, where the main plot was soil management (either conventional or minimum tillage), secondary was phosphorus rate over the soil (0; 100; 200 kg ha-1 P2O5), and tertiary was phosphorus rate on in sugarcane row (0; 90; 180 kg ha-1 P2O5). Soil chemical parameters were evaluated, as well as stems and sugar yield, technological aspects and nutrient extraction. AgroEstat was used for the statistical analysis. The results showed that minimum tillage provided higher phosphorus concentration on the soil top layer compared to the conventional tillage and the phosphorus excess caused reduction in the technological quality and yield of sugarcane.

Orientador: Ana Maria Rodrigues Cassiolato / Banca: Arnaldo Colozzi Filho / Banca: Luiz Malcolm Mano de Mello / Resumo: Vem sendo adotado no cerrado, cada vez mais, sistemas de manejos conservacionistas, como o plantio direto ou cultivo mínimo, que auxiliam na recuperação e na busca da sustentabilidade do agrossistema. Estes sistemas favorecem numerosos processos bioquímicos que ocorrem no solo devido à atividade microbiana, com efeitos sobre as propriedades físicas e químicas do solo e reflexos sobre o desenvolvimento das plantas, a produtividade agrícola e a qualidade do ambiente. Com isso, o objetivo deste trabalho foi quantificar o carbono da biomassa microbiana (CBM), o carbono do CO2 (C-CO2) liberado e a micorrização em função da calagem e do manejo do solo, em uma área de 20 anos de plantio direto, nas culturas de feijão (cultura de inverno) e milho (cultura de verão). O experimento foi conduzido na Fazenda de Ensino e Pesquisa da Faculdade de Engenharia, UNESP, Campus de Ilha Solteira, localizada no município de Selvíria-MS. O delineamento experimental utilizado foi o de blocos ao acaso, com parcelas subdivididas, constituídas de 2 tratamentos (principais), 2 doses de calcário e 4 repetições cada. Os tratamentos foram: T1 - Plantio direto - calcário na superfície, sem incorporação; e T2 - Cultivo Mínimo - incorporação de calcário com o escarificador; e as doses de calcários foram: D1 - Testemunha (sem calcário) e D2 - 2000 kg ha-1 de calcário. O solo foi reclassificado como LATOSSOLO VERMELHO distrófico. Após amostragem (de 0 - 0,10 m de profundidade), o solo foi seco, peneirado (2 mm) e enviado para análise das características químicas. O CBM foi avaliado pelo método de fumigação-extração e a atividade respiratória foi verificada pela quantificação do C-CO2 liberado. Para as avaliações da porcentagem de segmentos de raízes colonizadas por fungos micorrízicos arbusculares as raízes foram clareadas, acidificadas, coloridas com azul de... (Resumo completo, clicar acesso eletrônico abaixo). / Abstract: There is a steady increase in the employment of conservation management systems such as no-tillage or minimum-tillage in the Brazilian 'cerrado', which help in the recovery and maintenance of the agrosystem sustainability. These systems benefits several biochemical processes that take place in the soil due to microbial activity, which impact its physical and chemical properties and reflect on the development of plants, agricultural yield and the environment quality. The objective of this research was to quantify the microbial biomas-C, the C-CO2 evaluated and the mycorrhization in relation to limestone application and soil management, in a site under no-tillage for 20 years. The experiment was deployed at the Teaching and Research Farm (Selvíria, Mato Grosso do Sul State, Brazil) of the College of Engineering of Ilha Solteira, UNESP. The experimental design was a split plot, with two managements (main) and two levels of limestone, with four replications each. Treatments were T1 - No-tillage: surface limestone application, with no incorporation and T2 - Minimum-tillage: limestone incorporation with chisel plowing, while limestone levels were D1 - control (no limestone) and D2 - 2,000 kg ha-1 limestone. The soil was reclassified as a red 'latossol' (oxisol). After sampling the soil was dried, sieved (2 mm mesh) and analyzed for its chemical properties. The microbial biomass-C was estimated by the fumigation-extraction method and respiratory activity was estimated by the quantification of the C-CO2 evaluated. Roots were clarified, acidified, stained with 0.05 trypan blue and preserved in lactoglycerol in order to estimate the percentage of root colonization by arbuscular mycorrhizal fungi. The assessment of mycorrhizal colonization was performed in 40 segments (one cm long), for each replication and treatment, under a... (Complete abstract, click electronic address below). / Mestre