Fen?menos astron?micos como base de um livro para professores de ci?ncias.

Programa de P?s-Gradua??o em Ensino de Ci?ncias, Instituto de Ci?ncias Exatas e Biol?gicas, Universidade Federal de Ouro Preto.A Astronomia, no Ensino Fundamental, tem sua import?ncia reconhecida pelo PCNs (Par?metros Curriculares Nacionais): ?Observar n?o significa apenas ver, e sim buscar ver melhor, encontrar detalhes no objeto observado?. No entanto, o conte?do de Astronomia n?o ? estudado nos cursos de forma??o e capacita??o de professores, de maneira satisfat?ria, visto que muitos professores que ministram esse conte?do dizem possuir dificuldade ou conhecimento insuficiente para o Ensino de Astronomia. Al?m disso, os livros did?ticos trazem diversos erros conceituais, que refor?am as concep??es alternativas desses profissionais. ? preciso, portanto, buscar solu??es para esse problema e este trabalho tem por objetivo criar um curso de forma??o de professores, com base na corre??o dos erros conceituais encontrados em livros did?ticos, resultando na produ??o de um livro, contemplando os temas: Esta??es do Ano, Eclipses e Fases da Lua e Forma??o de Tempestades, al?m de uma caracteriza??o do Sistema Solar e fen?menos astron?micos e clim?ticos, contextualizados a outros planetas do nosso Sistema. O curso foi aplicado aos formandos em Licenciatura dos cursos de Biologia, F?sica e Qu?mica, da Universidade Federal de Ouro Preto, juntamente com dois question?rios para avalia??o do conhecimento dos alunos e satisfa??o do curso, respectivamente. Para analisar as respostas aos question?rios, utilizamos como referencial te?rico a An?lise de Conte?do, de Bardin, lendo e interpretando cada uma das respostas, inferindo nos significados que elas nos traziam, ao mesmo tempo levando em considera??o o contexto dos alunos e a Literatura sobre o assunto. Encontramos em todas as perguntas do question?rio a presen?a de respostas com concep??es alternativas, sendo levadas em considera??o durante a elabora??o do livro. Al?m disso, diversas sugest?es foram apontadas no question?rio de satisfa??o, como aumento da carga hor?ria do curso e utiliza??o de outras metodologias, como modelos tridimensionais (f?sicos e digitais) e outras m?dias, como v?deos. Apesar de um limitado tempo dispon?vel, para a realiza??o do curso e confec??o do livro, o produto se mostra como uma fonte confi?vel e abrangente de um conte?do te?rico sobre o nosso Sistema Solar, servindo como uma ?tima base para professores de Ci?ncias do Ensino Fundamental II.Astronomy in the Elementary School has its importance recognized by the PCN (Nacional Curriculum Parameters): ?observe does not only mean seeing, but seeking to see better, to find details in the observed object?. However, the content of Astronomy is not studied satisfactorily in the courses of formation and qualification of teachers, since many teachers who teach this content say they have enough difficulty or knowledge for the Teaching of Astronomy. In addition, textbooks bring several conceptual errors, which reinforce the alternative conceptions of these professionals. It is therefore necessary to seek solutions to this problem and this work aims to create a teacher training course, based on the correction of conceptual errors found in textbooks, resulting in the production of a book, covering the following themes: Seasons of the Year, Eclipses and Phases of the Moon, and Formation of Storms, besides a characterization of the Solar System and astronomical and climatic phenomena, contextualized to other planets of our System. The course was applied to undergraduate students in the Biology, Physics and Chemistry courses of the Universidade Federal de Ouro Preto, together with two questionnaires to evaluate students' knowledge and course satisfaction, respectively. To analyze the answers to the questionnaires, we used Bardin's Content Analysis as a theoretical reference, reading and interpreting each one of the answers, inferring in the meanings they brought us, while considering the context of the students and the Literature on the subject matter. We found in all the questions of the questionnaire the presence of answers with alternative conceptions, being considered during the elaboration of the book. In addition, several suggestions were pointed out in the satisfaction questionnaire, such as increasing the course load and using other methodologies, such as three-dimensional models (physical and digital) and other media, such as videos. Despite the limited time available for the course and preparation of the book, the product shows itself as a reliable and comprehensive source of theoretical content about our solar system, serving as a great base for elementary school science teachers

Limited effects of fire disturbances on the species diversity and structure of ant-plant interaction networks in Brazilian Cerrado.

Fire is one of the main natural disturbances in Tropical Savannas, changing the diversity of species, altering the structure of species interactions, and driving the evolution of adaptations. Here, we investigated the effects of fire disturbance on interactions between ants and plants with extrafloral nectaries in Cerrado (Brazilian Savanna). We carried out the study in two different ecosystems of Brazilian Cerrado 700 km apart; Woody Cerrado and Rupestrian Grasslands. We conducted a Before-After-Control-Impact (BACI) experiment, in which the impact was the disturbance caused by fire. In Woody Cerrado, we found no evidence of fire affecting the diversity and composition of plants or its interactions. Fire also did not affect ant diversity but changed the interaction pattern of its interactions by reorganizing the paired interactions between species (i.e., rewiring). However, this effect did not result in changes on the overall structure of the network. In Rupestrian Grasslands, fire also did not affect the diversity and composition of plant species or its interactions, but it did increase the number of ant species and change its composition, leading to a reorganization of the its paired interactions. However, these fire disturbances in the ant level did not affect the overall structure of the network. Our findings indicate that the structure of ant-plant interaction networks is robust to fire disturbances, more in Woody Cerrado than Rupestrian Grasslands, confirming our hypothesis that ant-plant interactions in Cerrado are adapted to fire disturbances. In sum, our study enhances the understanding of the effects of environmental disturbances and the stability of the ant-plant interactions in fire-adapted ecosystems such as Brazilian Cerrado