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A produção de cimento para o uso na construção civil tem gerado problemas socioambientais, portanto estratégias ecologicamente sustentáveis precisam ser desenvolvidas e implementadas. Em busca dessas soluções, pesquisadores têm utilizado microrganismos em misturas de materiais cimentícios buscando diminuir o uso do cimento Portland. Os microrganismos que produzem a enzima urease são capazes de metabolizar o cálcio quando disponível no meio e produzir calcita, que garante resistência aos materiais. Entretanto, a manutenção da viabilidade dos microrganismos e de sua bioatividade para posterior uso como um material de construção é um obstáculo. Por isso, o objetivo deste trabalho foi avaliar o potencial de armazenamento de um isolado de Bacillus sp. em biomassa vegetal e, posteriormente verificar as influências mecânicas deste material em argamassa de metacaulim sem adição de cimento Portland. Para isso, um isolado de Bacillus foi acondicionado em substrato de ervilhaca (Vicia villosa Roth) e, após revitalização, adicionado à mistura pozolânica sem cimento em dois traços diferentes. Os testes conduzidos comprovaram a eficiência da biomassa vegetal como mecanismo de armazenamento do microrganismo. A bactéria manteve sua capacidade de revitalização mesmo após o período de cura da argamassa. Foi desenvolvido um material de baixo custo, fácil manuseio e sustentável.

Copyright of Revista Brasileira de Engenharia Agricola e Ambiental - Agriambi is the property of Revista Brasileira de Engenharia Agricola e Ambiental and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In the production process Ocimum basilicum seeds, the substrate selection is an important characteristic in qualitative terms, as way to obtain a great culture development, in addition to reducing the production costs. The objective of this research was to analyze different concentrations of commercial substrate associated with a soil conditioner, based on tanned bovine manure, in the germination of O. basilicum seeds. The research was conducted under greenhouse conditions, in a completely randomized experimental design, and composed by six treatments [commercial substrate (100%) (T1); commercial substrate (80%) + tanned bovine manure (20%) (T2); commercial substrate (60%) + tanned bovine manure (40%) (T3); commercial substrate (40%) + tanned bovine manure (60%) (T4); commercial substrate (20%) + tanned bovine manure (80%) (T5); and tanned bovine manure (100%) (T6)], and six replicates, and each replicate was characterized by 10 cells from the tray. The seeds were placed into plastic polyethylene trays, under steel countertops. After filling the cells with each treatment, sowing was carried out, and after second day of planting, evaluation was carried out regarding the average number of germination seeds, germination speed index (GSI) and the average germination time (AGT). The best results were related to the treatments based on commercial substrate and also commercial substrate (80%) + tanned bovine manure (20%), with average seed germination above 78.33%, and addition to higher GSI, with average above 1.21, and lower AGT, whose average was below 6.78 days, showing the positive effect of the addition of up to 20% tanned bovine manure in the commercial substrate Carolina Soil®, regarding the germination of O. basilicum seeds. [ABSTRACT FROM AUTHOR]

Copyright of Revista de Arqueologia is the property of Revista de Arqueologia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista Chapingo Serie Horticultura is the property of Universidad Autonoma Chapingo and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Hydrophobicity is the phenomenon where the soil has reduced wettability, usually associated with coating of soil particles by hydrophobic organic substances. This study aimed to provide a description of the hydrophobicity occurrence, highlight recent discoveries about the origin of phenomenon and discuss the main hydro-physical properties and chemical processes linked to the development of hydrophobic behavior in soils. Hydrophobicity is associated with other factors such as soil moisture, presence of some fungi species, particle size, soil pH and occurrence of burnings. The causative substances may be provided by local vegetation, through deposition or decomposition. The dependence and combination of different factors that influence hydrophobicity in soils lead to a spatial and temporal variability of the phenomenon, with negative consequences in the processes of infiltration and water percolation, affecting the three-dimensional distribution and dynamics of soil moisture. Thus, the occurrence of a hydrophobic character requires special attention, especially regarding soil use and management.

This study had as objective to evaluate litter total deposition and litter from main species from Seasonal Deciduous Forest, in Itaara, RS. Thirty circular metal collectors were allocated in six plots. The litter was collected monthly, from January 2006 to December 2007. The litter was separated in leaves, thin branches (diameter < 1.0 cm) and miscellany (flowers, fruits, seeds and non identified plants). The leaves were separated considering the most representative species in the forest and the others were classified as “others”. The average annual litter deposition was 5.85 Mg ha-1 year-1, composed 63.2% of leaves, 19.6% of miscellany and 17.1% of thin branches. Parapiptadenia rigida, Ocotea pulchella and Matayba elaeagnoides were responsible for about 30% from total litter deposition. The leaves deposition of Lithraea molleoides, Cupania vernalis, Nectandra megapotamica and Matayba elaeagnoides increased significantly when rainfall increased and Parapiptadenia rigida increased when the air temperature decreased.

Greenhouse experiments were conducted to evaluate the effect of soil amendment with chopped (1cm²) or ground (1mm sieve) dry leaves of assa-peixe (Vernonia polyanthes), lemon-grass (Cymbopogon citratus), eucalyptus (Eucalyptus citriodora), castor (Ricinus communis), mango (Mangifera indica) or neem (Azadirachta indica) for the control Meloidogyne javanica. Into the soil (Yellow red oxisol) of each pot were added leaves (5g kg-1 of soil) and 5,000 eggs of the nematode. After seven days, one tomato seedling "Santa Cruz Kada" was transplanted to each pot. The tomato root weight, galls and eggs/root system were determined 60 days after transplant. None of the soil amendments reduced gall or eggs, when applied as leaf pieces. However, all tested plant species reduced the gall number, when they were incorporated into the soil as powder, and maximum nematode suppression occurred in soil amended with neem leaves (61%). The amendment with ground leaves of castor, neem, eucalyptus and lemon-grass reduced the number of eggs, with maximum reduction occurring in soil amended with ground castor leaves (69%), evidencing that these organic amendments can be an alternative for M. javanica control in tomato. Further studies are required under field conditions to confirm the potential of these organic amendments on the control of M. javanica.Experimentos em casa de vegetação foram conduzidos com o objetivo de avaliar o efeito da adição ao solo de folhas secas picadas (1cm²) ou trituradas (peneira de 1mm) de assa-peixe (Vernonia polyanthes), capim-limão (Cymbopogon citratus), eucalipto (Eucalyptus citriodora), mamona (Ricinus communis), manga (Mangifera indica) ou nim (Azadirachta indica) para o controle de Meloidogyne javanica. Ao solo de cada vaso (latossolo vermelho-amarelo), foram adicionadas folhas (5g kg-1 de solo) e 5.000 ovos do nematoide. Após sete dias, uma muda de tomateiro "Santa Cruz Kada" foi transplantada em cada vaso. O peso das raízes e os números de galhas e de ovos foram avaliados 60 dias após o transplantio. As folhas picadas de nenhuma planta reduziram o número de galhas e de ovos. Entretanto, as folhas de todas as plantas estudadas reduziram o número de galhas quando foram incorporadas ao solo na forma de pó e a máxima supressão foi obtida com as folhas de nim (61%). A adição ao solo de folhas trituradas de mamona, nim, eucalipto e capim-cidreira reduziu o número de ovos, com redução máxima após aplicação de folhas de mamona (69%), indicando que esses materiais orgânicos podem ser uma alternativa de controle de M. javanica em tomateiro. Novos estudos devem ser realizados em condições de campo para confirmar o potencial desses materiais orgânicos no controle de M. javanica.

The objective of this research is the chemical characterization of the PM10 for the winter and summer seasons in the urban and rural zones of Mexicali. The samplings were realized every other day, using low volume samplers with two types of filters, quartz and teflon. The filters were analyzed for total mass by gravimetry, 38 metals (Na to Pb) by X rays spectroscopy analysis, anions (Cl-, NO3-, SO42-) and cations (Na+, K+, NH4+) by ions chromatography, and organic and elemental carbon by thermal optimal transmittance. During the winter season the Mexican norm which is 120 μg m-3 averaged for 24 hours, was exceeded by 27 times, meanwhile in the summer season the norm was exceeded by 15 times. In the summer season the geological material predominated while in the winter was the organic material the predominant one. It is concluded that the urban zone was the most polluted in the summer and in the rural was more polluted in the winter. [ABSTRACT FROM AUTHOR]

Este trabalho teve como objetivo avaliar o efeito da solarização do solo associada à incorporação de materiais orgânicos dentro de sacos plásticos na incidência de patógenos radiculares e na produção de mudas de mamoeiro. Foram realizados dois experimentos em épocas distintas (época seca e época chuvosa). O delineamento utilizado foi inteiramente casualizado, em esquema fatorial de 4x2x2, com cinco repetições, sendo constituído por incorporação de matéria orgânica (sem matéria orgânica, mamona, mandioca brava e nim), solarização (com e sem) e período de tratamento (15 e 30 dias), respectivamente. Verificou-se que, a incorporação de mamona associada à solarização do solo, na época seca, proporcionou maiores valores no diâmetro do colo, número de folhas, altura da planta e massa seca. Contudo, na época chuvosa, a incorporação de mandioca brava e nim, associada à solarização do solo, proporcionou maiores valores no diâmetro do colo, número de folhas, altura da planta e massa seca. Verificou-se ainda que, o melhor período de incorporação de materiais (15 ou 30 dias), associado à solarização do solo, varia de acordo com o tipo de material utilizado.

Hydrophobicity is the phenomenon where the soil has reduced wettability, usually associated with coating of soil particles by hydrophobic organic substances. This study aimed to provide a description of the hydrophobicity occurrence, highlight recent discoveries about the origin of phenomenon and discuss the main hydro-physical properties and chemical processes linked to the development of hydrophobic behavior in soils. Hydrophobicity is associated with other factors such as soil moisture, presence of some fungi species, particle size, soil pH and occurrence of burnings. The causative substances may be provided by local vegetation, through deposition or decomposition. The dependence and combination of different factors that influence hydrophobicity in soils lead to a spatial and temporal variability of the phenomenon, with negative consequences in the processes of infi ltration and water percolation, affecting the three-dimensional distribution and dynamics of soil moisture. Thus, the occurrence of a hydrophobic character requires special attention, especially regarding soil use and management. [ABSTRACT FROM AUTHOR]

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Copyright of Ciência Florestal (01039954) is the property of Ciencia Florestal and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)