Large chestnut trees (Castanea sativa) respond poorly to liming and fertilizer application

Establishing a fertilization plan for large trees is particularly difficult due to the high soil volume that the roots exploit and the buffer effect of the perennial woody structure on the concentration of nutrients in the leaves. This work evaluates the response of chestnut, a very large tree, to different fertilizer solutions. The study was conducted in two chestnut orchards planted in acid soils that were subjected to the application of lime plus phosphorus (Lime+P), lime plus a compound NPK fertilizer (Lime+NPK), and an unfertilized control (Control). The effects of the treatments on soil properties, nutritional status and photosynthetic performance of the trees, and nut production, were assessed from field and laboratory analyses. Liming significantly increased soil pH and exchangeable calcium (Ca). Treatments did not significantly influence leaf P and K levels, although leaf N concentrations were significantly higher in the Lime+NPK treatment on two of the three sampling dates. In one of the trials, the average accumulated nut yield was higher in the Lime+NPK (71.7 kg tree−1) treatment compared with the control (59.6 kg tree−1) and the Lime+P (51.7 kg tree−1) treatments, although without significant differences at P < 0.05. Overall, the results show the chestnut tree to be a species tolerant of soil acidity. The results also show that the buffer capacity of the plant in regulating the nutrient concentration in the leaves seems to be higher for P than for N, and therefore, concentrations of N in the leaves require the regular application of the nutrient as a fertilizer.The authors are grateful to the Foundation for Science and Technology (FCT, Portugal) and FEDER under Programme PT2020 for financial support to CIMO (UID/AGR/00690/2015) and FEADER (The European Agricultural Fund for Rural Development) through the project CMP122 - PDR2020-101-030981 – EGIS, Estratégias para uma Gestão Integrada do Solo e da Água em Espécies Produtoras de Frutos Secos. We also thank João Paulo Roxo and Carlos Lopes for allowing the experiments to be conducted on their farms.info:eu-repo/semantics/publishedVersio

Resposta do castanheiro à aplicação de calcário e fertilizantes minerais

A informação de base que suporta as recomendações de fertilização para o castanheiro é ainda pouco consistente. Os castanheiros são árvores de porte elevado que exploram um enorme volume de solo sendo insuficiente a informação que se retira das análises de terras. Por outro lado, o porte elevado das árvores faz com que respondam de forma lenta à aplicação de fertilizantes. Uma outra dificuldade resulta de ser difícil encontrar pomares adequados para conduzir estudos de fertilização devido à sua reduzida área e à elevada heterogeneidade das árvores. Neste trabalho reportam-se resultados de dois ensaios de campo que decorreram em Sobreiro e Tuizelo, no concelho de Vinhais, em que se estabeleceram três tratamentos, designadamente a aplicação de calcário mais fósforo (CalP), calcário mais um fertilizante NPK (CalNPK) e uma modalidade testemunha sem fertilização. Após três colheitas sucessivas, a produção não diferiu significativamente entre tratamentos em qualquer dos ensaios. No ensaio de Tuizelo, contudo, o tratamento CalNPK originou produção média acumulada (71,7 kg/árvore) mais elevada que a modalidade testemunha (59, 7 kg/árvore). A concentração de nutrientes nas folhas e algumas propriedades do solo parecem também mostrar os benefícios da aplicação do fertilizante NPK, talvez devido à presença de azoto, o elemento reconhecido como mais importante na fertilização dos castanheiros em outros estudos realizados na região.Projeto EGIS - Estratégias para uma Gestão Integrada do Solo e da Agua em Espécies Produtoras de Frutos Secos.info:eu-repo/semantics/publishedVersio

Ensino de geografia, conceito de paisagem e o livro didático

As discussões sobre o ensino de geografia são amplas e esse texto abordou o conceito de paisagem enquanto fundamento científico relacionado com o livro didático na escola. O artigo busca compreender o processo de ensino-aprendizagem de Geografia e, especificamente do conceito de paisagem, nos Anos Iniciais do Ensino Fundamental, em escolas da Rede Municipal de Ensino de Teresina/Piauí além de discorrer sobre o ensino de Geografia e o conceito de paisagem, nos Anos Iniciais, bem como observar as concepções de ensino de Geografia e de paisagem presentes no livro didático do referido componente curricular. Realizou-se uma pesquisa bibliográfica além de uma análise do livro didático de Geografia, do “terceiro ano”, da coleção “Aprender Juntos”, da autora Leda Leonardo da Silva e que é adotado na Rede Municipal de Ensino, acima citada. Como aporte teórico foram estudados autores que são referências no campo do ensino de Geografia e do ensino de Geografia nos anos Iniciais. Como resultados foram verificados a importância do conceito de paisagem para o ensino de geografia bem como a necessidade de estudar o conceito nos anos iniciais a partir do livro do didático. Concluiu-se que A aprendizagem significativa dos conceitos geográficos possibilita a formação de cidadãos críticos, aptos a atuar na sociedade em constante transformação especialmente o conceito de paisagem estudado nos anos iniciais na escola

Educação Geográfica Para a Cidadania na Perspectiva do Currículo de Teresina/Piauí/Brasil

Educar para a cidadania significa formar pessoas autônomas, que conheçam e exerçam os seus direitos e deveres em sociedade, a partir de discussões científicas realizadas em situações de ensino-aprendizagem escolar por meio da mediação didática. Nesse contexto, o texto tem como objetivo discutir a contribuição da disciplina Geografia, enquanto integrante da estrutura curricular utilizada na rede municipal de ensino de Teresina/PI, como possibilidade para a formação cidadã na realidade escolar. A pesquisa bibliográfica em educação geográfica para a cidadania fundamentou-se em Callai (2001; 2018), Cavalcanti (2012) e García-Perez (2021) e a pesquisa documental a partir de Brasil (2018) Base Nacional Comum Curricular-BNCC e do Novo Currículo para Geografia conforme Teresina (2018). Devido à complexidade de estudar todos os anos, optou-se pelos anos iniciais (do 1º ao 5º ano) com vistas a perceber as características da formação e promoção da cidadania a partir do ensino de Geografia com ênfase nas unidades temáticas e objetos do conhecimento. Concluiu-se que a valorização de práticas educativas na perspectiva da construção da cidadania, pois foi revisado e atualizado de acordo com as orientações da BNCC. Dessa maneira, a Geografia é necessária como contribuição no processo de ensino-aprendizagem, ao promover reflexões sobre a sua vivência, em parceria com docentes, currículo e escola, no sentido de que os conhecimentos geográficos no currículo sejam estudados e não se caracterizem meramente como utopia

A controlled-release fertilizer improved soil fertility but not olive tree performance

The use of a controlled-release fertilizer (CRF) was studied in a traditional rainfed olive grove in a Mediterranean climate where precipitation is very irregular, particularly in the spring. The objective of the study was to assess whether a CRF can improve the olive tree's performance compared to a conventional nitrogen (N) fertilizer (CF), by supplying N gradually and reducing the risk of potential N loss from leaching. The fertilized treatments showed better plant N nutritional status, which resulted in enhanced net photosynthesis and higher leaf concentrations of total soluble sugars, chlorophylls and soluble proteins which, in turn, increased olive yield by 43% in comparison to the unfertilized control. However, in general, no significant differences were found between fertilized treatments in the performance parameters of the trees evaluated, including olive yield. Somewhat unexpectedly, CRF consistently increased the soil organic carbon (C) (29%), kjeldahl-N (75%) and easily extractable glomalin-related soil proteins (EE-GRSP) (60%) and total GRSP (T-GRSP) (122%) compared to the CF. The result was ascribed to a stimulus on the development of herbaceous vegetation and eventually on the activity of the roots of the trees due to the higher soil inorganic-N availability in the autumn. Thus, some soil inorganic-N in the autumn seems to comprise a low risk of leaching, since weeds act as a catch crop and convert this inorganic N into an organic substrate, with potential benefits in the long-term for the agro-system.Doctoral fellowship under the Doctoral Program ‘‘Agricultural Production Chains—from fork to farm’’ (PD/00122/2012) provided by the FCT-Portuguese Foundation for Science and Technology to E. Silva (PD/BD/128274/2017). This research was funded by the Foundation for Science and Technology (FCT, Portugal) and FEDER under Programme PT2020 for financial support to CIMO (UIDB/00690/2020) and CITAB (UIDB/04033/2020). The research was integrated in the activities of the Operational Group ‘‘Novas práticas em olivais de sequeiro: estratégias de mitigação e adaptação às alterações climáticas’’, funded by PT2020 and EAFRD (European Agricultural Fund for Rural Development).info:eu-repo/semantics/publishedVersio

Photosynthesis, yield, nutrient availability and soil properties after biochar, zeolites or mycorrhizal inoculum application to a mature rainfed olive orchard

Soil conditioners and beneficial microorganisms are important tools that can be used to increase the sustainability of agro-systems. However, the high diversity of conditions where they can be applied may influence the results, which requires extensive field research. In this study, a field trial of four years was conducted in olive (Olea europaea L.) to assess the effect of biochar, zeolites and a commercial mycorrhizal inoculum in the photosynthetic performance, nutritional status of trees, olive yield and soil properties. The experimental design also included a fertilizer treatment with nitrogen (N), phosphorus (P), potassium (K) and boron (B), which nutrients were applied at 50 kg ha1 of N, P2O5 and K2O and 2 kg ha1 of B, and an untreated control. The mineral fertilizer treatment increased significantly the dry mass of pruning wood and the average olive yield by 21% over the control treatment. The mineral treatment increased plant N nutritional status, the most likely reason why the trees of this treatment performed better. Overall, the soil treatments had net photosynthetic rates similar to each other and higher than the control treatment, from the second year onwards. Biochar increased soil organic matter, as a result of the carbon (C) contained in the amendment itself, and probably by stimulating soil biological activity. Biochar and zeolites did not improve the productive performances of the tress, but increased the soil cation exchange capacity (CEC), which can benefit the system in the long-term. Mycorrhizal fungi did not show any benefit for soil or plants, which could mean that mycorrhization was not established, or their effect was not better than that of native microorganisms. In the conditions of this study, the interest of using commercial mycorrhizal fungi in a mature olive orchard seems to be low.This work was funded by the Operational Group “Novas práticas em olivais de sequeiro: estratégias de mitigação e adaptação às alterações climáticas”, funded by PT2020 and EAFRD (European Agricultural Fund for Rural Development). The authors are grateful to the Foundation for Science and Technology (FCT, Portugal) and FEDER under Programme PT2020 for financial support to CIMO (UIDB/00690/2020) and CITAB (UIDB/04033/2020) and also to AgriFood XXI project, nº. NORTE-01-0145-FEDER-000041, co-financed by the European Regional Development Fund (ERDF) through NORTE 2020 (North Regional Operational Program 2014/2020).info:eu-repo/semantics/publishedVersio

Large chestnut trees did not respond to annual fertiliser applications, requiring a long-term approach to establishing effective fertilisation plans

Due to the high value of the fruit, the European chestnut (Castanea sativa Mill.), usually grown in agroforestry systems, has been planted as a single species in orchards managed with increasingly intensive cropping practices, such as the regular use of fertilisers. This justifies research into establishing fertilisation programmes oriented towards ecological intensification. In this study, the results of fruit production, plant nutritional status and soil properties are reported from a field trial in which three NPK fertilisers (20:7:10, 13:11:21 and 7:14:14) and a control treatment were used. Chestnut yields did not vary significantly between treatments, although the mean values of the control showed a clear downward trend. N supplied by the fertilisers seems to have been the most important factor in the difference between the fertilised and control treatments, since leaf N concentrations were lower in the control and often below the lower limit of the sufficiency range. Soil inorganic N levels in the autumn, and tissue N concentrations of the herbaceous vegetation developing beneath the trees, indicated risks of N loss to the environment and highlighted the importance of this vegetation remaining during the winter. The chestnuts’ poor response to fertiliser applications was attributed to the buffering effect of the large perennial structure of the trees on the distribution of nutrients to the growing plant parts. In large trees, it seems appropriate to base the annual fertilisation plan on leaf nutrient concentration. Thus, farmers probably should avoid spending money on fertilizer applications as long as leaf nutrient concentrations do not approach the lower limits of sufficiency ranges.This work was funded by the Operational Group “EGIS–Estratégias de Gestão Integrada do Solo e da Água em Espécies Produtoras de Frutos Secos”, funded by PT2020 and EAFRD (European Agricultural Fund for Rural Development). The authors are also grateful to the Foundation for Science and Technology (FCT, Portugal) for financial support through national funds FCT/MCTES (PIDDAC) to CIMO (UIDB/00690/2020 and UIDP/00690/2020), SusTEC (LA/P/0007/2021) and CITAB (UIDB/04033/2020)info:eu-repo/semantics/publishedVersio

Beta Contábil Versus Beta CAPM: Uma Investigação Empírica no Mercado Financeiro Brasileiro

Uma das questões, atualmente discutidas na Moderna Teoria de Finanças diz respeito à avaliação do risco e do retorno no processo de decisão de investimento. Levando-se em conta as premissas desta Teoria, um dos parâmetros de avaliação do risco é através do “beta” extraído do modelo CAPM. No entanto, o desenvolvimento teórico deste modelo está totalmente embasado em uma dinâmica de mercado acionário forte, o que dificulta a sua plena aplicação em mercados com predominância de empresas com Capital Fechado, como o brasileiro. Por outro lado, vem desenvolvendo-se alternativas, na literatura, para esta problemática, e uma delas é o que se convencionou chamar de Beta Contábil, devido a utilização da informação contábil para sua concepção. Diante deste contexto, o artigo em tela teve por objetivo verificar a hipótese da utilização do Beta Contábil em substituição do Beta CAPM para empresas de capital fechado. Para tanto, foi utilizado um estudo empírico, através de prova não-paramétrica Mann-Whitney U, em ações de empresas do setor siderúrgico e metalúrgico extraídos do Banco de Dados da Consultoria Economática, no período de 2001 a 2005. Concluiu-se, por fim, através dos resultados obtidos, que o Beta Contábil substitui significativamente, o Beta CAPM, para a amostra selecionada

Actions and reactions to obstetric violence: a qualitative study about waterbirth

This text is part of a research carried out between 2015 and 2016 aimed to investigate the social representations developed by women who gave birth in water about this type of birth. This is a qualitative study carried out with women who experienced waterbirth in a public and private hospital in Portugal. This article is part of this research, seeking to focus on an important theme seized in this investigation: obstetric violence. We seek to discuss the forms of obstetric violence present in the reports of women who have experienced waterbirth. Methodologically, the research was qualitative, using the snowball technique for access to participants and interviews with them. As a result, the existence of resistance and reactions of women is highlighted who, by naming the practices of obstetric violence, including disrespect in the birth scenario, sought to break in different ways with the asymmetry of the relationship with the child health professional, either by silencing and seeking contact with another professional in the care relationship or by denying the impositions to which they were submitted

Production of silica gel from residual rice husk ash

This paper presents a study on the production of silica gel in hydrothermal process using residual rice husk ash. Measurements of the chemical composition, X-ray diffraction, infrared spectroscopy, particle size distribution, and pozzolanic activity were carried out in order to characterize the obtained material, and the optimal silica gel was selected for use as a mineral additive in cement pastes. The compressive strengths were determined for cement pastes containing silica gel (0.0, 2.5 or 5% by mass) in different times. The results indicate that the mixtures containing silica gel showed improved mechanical behavior over all time periods evaluated.FAPEAMCoordenacao de Aperfeicoamento de Pessoal de Nivel Superior (CAPES)CNP