Implications of converting native forest areas to agricultural systems on the dynamics of CO2 emission and carbon stock in a Cerrado soil, Brazil.

The conversion of native vegetation to agricultural areas leads to a natural process of carbon loss but these systems can stabilize in terms of carbon dynamics depending on the management and conversion time, presenting potential to both store and stabilize this carbon in the soil, resulting in lower soil respiration rates. In this context, this study aimed to investigate the effect of converting native Cerrado forest areas to agricultural systems with a forest planted with Eucalyptus camaldulensis and silvopastoral systems on the dynamics of CO2 emission and carbon stock at different soil depths. The experimental sites are located in the Midwest of Brazil, in the coordinates 20°22'31″ S and 51°24'12″ W. Were evaluated soil CO2 emission (FCO2), soil organic carbon, the degree of humification of soil organic matter (HLIFS), soil temperature, soil moisture, and soil chemical and physical attributes. The soil of the area is classified as an Oxisol (Haplic Acrustox). Soil samples were collected at depths of 0.00-0.10, 0.10-0.20, 0.20-0.30, and 0.30-0.40 m. The lowest FCO2 values were found in the silvopastoral system (1.05 µmol m-2 s-1), followed by the native forest (1.65 µmol m-2 s-1) and the eucalyptus system (1.96 µmol m-2 s-1), indicating a 36% reduction in FCO2 compared to the conversion of the native forest to the silvopastoral system and an increase of 19% when converting the native forest to the eucalyptus system. The soil chemical attributes (N, K+, Ca2+, H++Al3+, CEC, and organic carbon) showed a decrease along the profile. The shallowest depths (0.00-0.10 and 0.10-0.20 m) presented no differences between systems but the subsequent depths (0.20-0.30 and 0.30-0.40 m) had a difference (95% confidence interval), relative to N, Ca2+, H++Al3, CEC, and organic carbon stock (OCS), and the soil under silvopastoral system showed a higher concentration of these attributes than the native forest. The multivariate analysis showed that the eucalyptus and silvopastoral systems did not differ from the forest in the shallowest soil layer but differed from each other. This behavior changed from the second assessed depth (0.10-0.20 m), in which the silvopastoral system stands out, differing both from the eucalyptus system and from the native forest, and this behavior is maintained at the following depths (0.20-0.30 and 0.30-0.40 m). OCS, H++Al3, CEC, and nitrogen are strongly related to land use change for silvopastoral system. Regarding the behavior/relationship of attributes as a function of depth, the silvopastoral system contributed to soil carbon accumulation and stability over consecutive years.

Motivação do idoso e sua satisfação para o uso de dispositivos eletrônicos de amplificação sonora individual / Motivation in the elderly and their satisfaction during the use of hearing aids

Este estudo teve como objetivo avaliar a satisfação de idosos com o uso de aparelho de amplificação sonora individual (AASI). Além disso, buscaram-se correlações e associações da satisfação com as restrições de participação decorrentes da deficiência auditiva e com a disposição dos idosos para o uso da amplificação sonora, respectivamente. Trata-se de um estudo do tipo observacional, descritivo, analítico, de delineamento transversal, desenvolvido com 31 idosos portadores de perda auditiva neurossensorial de grau leve a moderadamente severo e usuários de AASI pela primeira vez. Os participantes foram distribuídos em dois grupos, a saber: Grupo I: composto por idosos que compareceram ao centro auditivo por vontade própria, e Grupo II: idosos que compareceram ao centro auditivo por encaminhamento de familiar. Os idosos responderam dois questionários, sendo um para analisar as restrições de participação decorrentes da deficiência auditiva e o outro para avaliar a satisfação com o uso da amplificação sonora. Os dados obtidos passaram por uma análise estatística descritiva e inferencial sendo estabelecido nível de significância de 5%. As análises evidenciaram que os idosos se mostraram satisfeitos com o uso dos AASI e que não houve diferença nos resultados tanto com relação às restrições de participação quanto à satisfação quando comparados os idosos que procuraram o serviço por vontade própria ou por indicação de um familiar. (AU)

This study aims at evaluating the satisfaction of the elderly when using hearing aids. Furthermore, there were researches on correlations and associations of this satisfaction with the participation restrictions due to hearing impairment and with the elderly's willingness of using these devices, respectively. This is an observational, descriptive, analytical and cross-sectional study, conducted with 31 elderlies with sensorineural hearing loss from mild to moderately-severe and first-time hearing aid users. The participants were divided into twogroups, as the following: Group I: composed of elderly who came to the hearing center on their own will, and Group II: elderlies which came to the hearing center by family referral. The elderly answered two questionnaires, the first was developed to analyze the participation restrictions due to hearing impairment and the second to evaluate their satisfaction toward using hearing aids. The collected data underwent a descriptive and inferential statistical analysis with established significance at 5%. The analyzes have shown that the elderly were satisfied with the use of hearing aids and that there was no difference in the results regarding both participation restrictions and satisfaction when compared to the elderly that came to the hearing center on their own will or by indication of a relative. (AU)