52 research outputs found
Balanço e anålise da sustentabilidade energética na produção orgùnica de hortaliças.
Os insumos e serviços utilizados na produção vegetal representam custo energĂ©tico. Dependendo desses fatores e das produtividades obtidas, a conversĂŁo da produção em energia determinarĂĄ a eficiĂȘncia energĂ©tica do sistema. A agricultura orgĂąnica somente atingirĂĄ a missĂŁo de preservação ambiental se tiver comprovada sustentabilidade energĂ©tica. Neste trabalho, objetivou-se caracterizar os balanços energĂ©ticos dos cultivos orgĂąnicos e analisar sua sustentabilidade, em comparação aos sistemas convencionais. Monitoraram-se campos de produção de dez culturas, de 1991 a 2000 em Domingos Martins-ES. Os dados do sistema convencional foram obtidos pelas mĂ©dias dos coeficientes tĂ©cnicos da regiĂŁo. Quantificaram-se os coeficientes tĂ©cnicos, convertendo suas grandezas fĂsicas em equivalentes energĂ©ticos, expressos em kcal. O sistema orgĂąnico gastou 4.571.159 kcal ha-1 e apresentou 12.696.712 kcal ha-1 de energia inserida na colheita, mostrando balanço mĂ©dio de 2,78. Esse valor foi similar ao obtido no sistema convencional (1,93). As participaçÔes dos componentes nos gastos do sistema orgĂąnico foram embalagem (35,8%), composto orgĂąnico (17,2%), irrigação (12,6%), sementes/mudas (12,4%) e mĂŁo-de-obra (11,0%), serviços mecĂąnicos (5,0%) e frete (4,5%). Se os custos com embalagens fossem eliminados, os gastos do sistema orgĂąnico seriam reduzidos para 2.930.113 kcal ha-1, aumentando sua eficiĂȘncia. A maioria dos cultivos orgĂąnicos pode ser considerada sustentĂĄvel em transformação de energia, com balanços superiores a 1,00 e produção mĂ©dia diĂĄria de 80.421 kcal ha-1 por dia, superior Ă necessidade mĂnima de 58.064 kcal ha-1
Surface runoff and accelerated erosion in a periâurban wellhead area in southeastern Brazil
Degradation of hydrological conditions can adversely impact water resource quality and quantity. This degradation can
generate social and economic losses, including losses for users outside the basin area. Therefore, studies focusing on surface
runof and accelerated erosion processes are needed to enable interventions that address degradation-induced challenges.
In the present study, the surface runof and accelerated erosion potential of the FeijĂŁo River basin were presented in charts
at a 1:50,000 scale. The FeijĂŁo River basin has an area of 243.16Â km2
and is used as the main water source for the city of
SĂŁo Carlos, Brazil. Geoenvironmental attributes, such as substrate, climate, relief, soil, water bodies and land cover and
use, were integrated and assessed in a GIS environment, using a multicriteria analysis and weighted sum tool. The results
show that a large part of the area (86.12% of the basin) exhibits a low surface runof potential and a moderate accelerated
erosion potential. Accelerated erosive processes are triggered by changes in soil cover and have a direct relationship with the
removal of existing vegetation and implementation of anthropogenic activities. In this case, as well as for most of the areas
in southeastern Brazil, extensive grazing followed by sugar cane cultivation was the main driving force of erosion, acting as
trigger for accelerated erosive processes at the water source area
International Consensus Statement on Rhinology and Allergy: Rhinosinusitis
Background: The 5 years since the publication of the first International Consensus Statement on Allergy and Rhinology: Rhinosinusitis (ICARâRS) has witnessed foundational progress in our understanding and treatment of rhinologic disease. These advances are reflected within the more than 40 new topics covered within the ICARâRSâ2021 as well as updates to the original 140 topics. This executive summary consolidates the evidenceâbased findings of the document. Methods: ICARâRS presents over 180 topics in the forms of evidenceâbased reviews with recommendations (EBRRs), evidenceâbased reviews, and literature reviews. The highest grade structured recommendations of the EBRR sections are summarized in this executive summary. Results: ICARâRSâ2021 covers 22 topics regarding the medical management of RS, which are grade A/B and are presented in the executive summary. Additionally, 4 topics regarding the surgical management of RS are grade A/B and are presented in the executive summary. Finally, a comprehensive evidenceâbased management algorithm is provided. Conclusion: This ICARâRSâ2021 executive summary provides a compilation of the evidenceâbased recommendations for medical and surgical treatment of the most common forms of RS
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