Enraizamento de miniestacas e qualidade de mudas de Cordia trichotoma

The objective of this work was to evaluate the effects of indolebutyric acid (IBA) concentration, substrate composition and volume, and propagule type on the adventitious rooting and quality of Cordia trichotoma plantlets produced by mini-cuttings. Mini-cuttings were evaluated for rooting percentage and root number and length at 30 and 60 days of cultivation. Plantlets were evaluated for shoot height and stem diameter at 30, 60, 90, and 120 days of cultivation. The Dickson quality index, number of leaves, and fresh and dry weights of shoots and roots were also determined at 120 days of cultivation. The experiments were carried out in a completely randomized design, with six replicates, in a greenhouse, evaluating different concentrations of IBA, substrate composition and volume, and propagule type for adventitious rooting. Plantlets of C. trichotoma can be produced with quality and proper rooting from mini-cuttings with one or two buds or multiple buds (apical) when treated with 3,000 mg L-1 IBA and planted in 110 cm3 tubes containing equal proportions of substrate and vermiculite.O objetivo deste trabalho foi avaliar a concentração de ácido indolbutírico (AIB), a composição e o volume do substrato, e o tipo de propágulo no enraizamento adventício e na qualidade de mudas de Cordia trichotoma produzidas por miniestaquia. As miniestacas foram avaliadas quanto à percentagem de enraizamento e número e comprimento de raízes aos 30 e 60 dias de cultivo. Já as mudas foram avaliadas quanto à altura da parte aérea e diâmetro do colo aos 30, 60, 90 e 120 dias de cultivo. O índice de qualidade de Dickson, o número de folhas, e a massa fresca e seca da parte aérea e das raízes também foram determinados aos 120 dias de cultivo. Os experimentos foram conduzidos em delineamento inteiramente casualizado, com seis repetições, em casa de vegetação, tendo-se avaliado diferentes concentrações de AIB, composição e volume do substrato, e tipo de propágulo no enraizamento adventício. As mudas de C. trichotoma podem ser produzidas com qualidade e enraizamento adequado a partir de miniestacas de uma ou duas gemas ou de múltiplas gemas (apicais) quando tratadas com 3.000 mg L-1 de AIB e plantadas em tubetes de 110 cm3 contendo igual proporção de substrato comercial e vermiculita

ANÁLISE DOS IMPACTOS AMBIENTAIS DO USO DO BIOGÁS DE ATERROS SANITÁRIOS PARA A GERAÇÃO DE ENERGIA ELÉTRICA: APLICAÇÃO NO ATERRO METROPOLITANO SANTA TECLA.

Este artigo objetiva apresentar procedimento para a análise de viabilidade ambiental relacionado à geração de energia elétrica, com a utilização do biogás, proveniente da decomposição anaeróbica de resíduos em aterros sanitários com aplicação no Aterro Sanitário Metropolitano Santa Tecla, localizado em Gravataí - RS. O trabalho determina o potencial de geração de gás metano, sua capacidade de geração de energia elétrica e a avaliação ambiental. Sendo a avaliação dividida em três fases: pré-análise, análise e pós-análise. Para a obtenção dos impactos ambientais, foram utilizadas as metodologias MECAIA e LCA. Os impactos mais nocivos ao meio ambiente são gerados pelos resíduos e efluentes, chamando atenção às emissões, especialmente, a etapa de queima do biogás. A instalação da usina de geração de energia elétrica beneficia financeiramente os proprietários do aterro, em virtude da comercialização do biogás, nesse caso as prefeituras municipais. Também pode ser estendido à comunidade, com a diminuição da taxa de limpeza urbana e da taxa de iluminação pública pela energia elétrica gerada; além de contribuir para o superávit da balança comercial pela venda de créditos de carbono. O sistema elétrico seria beneficiado pela diversificação da matriz energética. Palavras-chave: impacto ambiental; aterro sanitário; biogás ABSTRACT Analysis of environmental impacts of the use of biogas landfill for electric power generation: application in metropolitan landfill Santa Tecla. This paper aims to present procedures for the analysis of environmental feasibility related to the generation of electricity with the use of biogas, from the anaerobic decomposition of waste in landfills with application in Santa Tecla Metropolitan Sanitary Landfill, located in Gravataí/RS. The work provides the potential to generate methane gas, its ability to generate electric energy and environmental assessment. The assessment is divided into three phases: pre-testing, analysis and post analysis. To obtain the environmental impacts were used methodologies MECAIA and LCA. The most harmful impacts to the environment are generated by waste and effluents, calling attention to issues, particularly the step of burning the biogas. The installation of the plant to generate electricity benefits financially the owners of the landfill, due to the marketing of biogas, in this case the municipal governments. It can also be extended to the community with a decrease in the rate of urban cleaning and the rate of public lighting by electricity generated, in addition to contributing to the surplus of trade balance for the sale of carbon credits. The electrical system would benefit by diversifying the energy matrix. Key words: environmental impact, landfill, bioga

Robotic milking of dairy cows: a Review

An innovative technology that currently tries to gain market share are milking robots. Despite the high costs, robotic milking may produce benefits for the farmer and for animals submitted to this system. The objective of this study was to perform a literature review on the use of robotic milking of dairy cows, addressing aspects such as implementation and functioning of the system and effect on milking frequency, milk production and composition, somatic cell count, mastitis, reproduction, and animal welfare. The results showed that the programming of the robot depends on the number of animals to be milked daily and on the milking frequency adopted in each batch. The implementation of the system mainly depends on the site where the facilities will be built and already existing structures on the farm. The milking frequency is higher for high-producing cows and at the beginning of lactation and is influenced by the palatability of the concentrate offered at the time of milking. Frequencies higher than three times per day reduce total milk fat production and increase the concentration of free fatty acids. The incidence of mastitis and somatic cell count tend to increase in the first three months after implementation of the system. After the second year, udder health tends to improve, normalizing mastitis incidence and somatic cell count. Reproduction of the cows is not affected if dry matter intake compensates the higher energy expenditure required for higher milk productions. Robotic milking improves cow welfare since the animals voluntarily turn to the robot when they feel discomfort

Collaborative research in Brazil: Differences between public and private sectors networks

Presented at the GLOBELICS 6th International Conference 2008 22-24 September, Mexico City, Mexico