33 research outputs found
Phosphorus extractors for irrigated rice on soils under reactive phosphate fertilization
Os fosfatos naturais reativos têm sido utilizados como fonte alternativa de fósforo (P) à cultura de arroz irrigado no estado do Rio Grande do Sul. O extrator Mehlich-1 é o método ofi cial de avaliação na disponibilidade de P em solos adubados com fonte solúveis, mas pode ser inadequado para solos adubados com fosfatos naturais, devido à possibilidade de dissolução excessiva das partículas de fosfatos naturais reativos por este extrator. Desenvolveu-se um experimento em casa de vegetação no Campus da PUC, RS, em Uruguaiana, no período de novembro a dezembro de 2009, com o objetivo de avaliar a disponibilidade de P em solos adubados com fosfato natural reativo, extraído pelo método da resina de troca aniônica (RTA), Mehlich-1 e Mehlich-3. Os solos foram previamente incubados com quatro doses de P (0; 9,82; 19,65 e 39,30 mg kg-1 de P) e cultivados com arroz irrigado durante 40 dias. Foram determinados os teores de P disponível extraído pelos diferentes extratores após o período de incubação. Durante o alagamento, foram analisados as concentrações de Fe, P e Ca e o pH na solução do solo. Após 40 dias de alagamento, foi avaliada a produção de matéria seca e a concentração de P na parte aérea das plantas. Os coefi cientes de determinação (r2 ) obtidos entre P acumulado pelas plantas de arroz e o P extraído foram: 0,84 para a Resina de troca iônica (RTA); 0,58 para o Mehlich-1 e 0,61 para o Mehlich-3. Dentre os métodos testados, o método da RTA foi mais efi ciente na extração de P do solo para avaliar a disponibilidade de P para a cultura de arroz irrigado em solos adubados com fosfatos naturais. A separação dos solos em grupos, segundo o material de origem e os teores de óxidos de ferro de baixa cristalinidade extraídos com oxalato a pH 6,0, resultou em melhor efi ciência de todos os métodos testados para avaliar a disponibilidade de P para o arroz irrigado em solo adubado com fosfato natural reativo.The reactive rock phosphates have been used as an alternative phosphorus (P) source for the irrigated rice culture in Rio Grande do Sul State. The extractor Mehlich-1 is used as the standard method for the assessment of the P availability. It can present satisfactory results when the fertilization of P in soil is carried out with a soluble source, but it can be inadequate for soils fertilized with rock phosphate, because of the possibility of dissolution of excessive reactive particles by this extractor. In order to evaluate the soil P availability in soils fertilized with rock phosphate, a greenhouse experiment on the campus of PUC, RS Uruguaiana in the period between September-October 2009 was carried out with four soils fertilized with four phosphate rates, where rice was cultivated for a 40 day period. The soil P availability was studied by the following extraction methods: anion exchange resin (AER), Mehlich-1 and Mehlich-3. The levels of available P extracted were assessed by different extractors after the incubation period. During the fl ooding, we analyzed the concentrations of Fe, Ca and P and the pH of the soil solution. After 40 days of fl ooding, the production of dry matter and P concentration were assessed in the plants’ shoots. The determination coeffi cients between the P accumulated by the plants and the content determined by the extraction methods were: 0.84 (anion exchange resin); 0.58 (Mehlich-1) and 0.61 (Mehlich-3). The results indicated that the anion exchange resin was more effective for predicting P availability for the irrigated rice culture in soil fertilized with rock phosphates. The separation of soils into groups according to the source material and the content of iron oxides of low crystallinity extracted with oxalate at pH 6.0, resulted in improved effi ciency of all tested methods to assess P availability for rice in soil fertilized with phosphate rock
Extratores de fósforo para o arroz irrigado em solos adubados com fosfato natural reativo
The reactive rock phosphates have been used as an alternative phosphorus (P) source for the irrigated rice culture in Rio Grande do Sul State. The extractor Mehlich-1 is used as the standard method for the assessment of the P availability. It can present satisfactory results when the fertilization of P in soil is carried out with a soluble source, but it can be inadequate for soils fertilized with rock phosphate, because of the possibility of dissolution of excessive reactive particles by this extractor. In order to evaluate the soil P availability in soils fertilized with rock phosphate, a greenhouse experiment on the campus of PUC, RS Uruguaiana in the period between September-October 2009 was carried out with four soils fertilized with four phosphate rates, where rice was cultivated for a 40 day period. The soil P availability was studied by the following extraction methods: anion exchange resin (AER), Mehlich-1 and Mehlich-3. The levels of available P extracted were assessed by different extractors after the incubation period. During the flooding, we analyzed the concentrations of Fe, Ca and P and the pH of the soil solution. After 40 days of flooding, the production of dry matter and P concentration were assessed in the plants’ shoots. The determination coefficients between the P accumulated by the plants and the content determined by the extraction methods were: 0.84 (anion exchange resin); 0.58 (Mehlich-1) and 0.61 (Mehlich-3). The results indicated that the anion exchange resin was more effective for predicting P availability for the irrigated rice culture in soil fertilized with rock phosphates. The separation of soils into groups according to the source material and the content of iron oxides of low crystallinity extracted with oxalate at pH 6.0, resulted in improved effi ciency of all tested methods to assess P availability for rice in soil fertilized with phosphate rock.Os fosfatos naturais reativos têm sido utilizados como fonte alternativa de fósforo (P) à cultura de arroz irrigado no estado do Rio Grande do Sul. O extrator Mehlich-1 é o método oficial de avaliação na disponibilidade de P em solos adubados com fonte solúveis, mas pode ser inadequado para solos adubados com fosfatos naturais, devido à possibilidade de dissolução excessiva das partículas de fosfatos naturais reativos por este extrator. Desenvolveu-se um experimento em casa de vegetação no Campus da PUC, RS, em Uruguaiana, no período de novembro a dezembro de 2009, com o objetivo de avaliar a disponibilidade de P em solos adubados com fosfato natural reativo, extraído pelo método da resina de troca aniônica (RTA), Mehlich-1 e Mehlich-3. Os solos foram previamente incubados com quatro doses de P (0; 9,82; 19,65 e 39,30 mg kg-1 de P) e cultivados com arroz irrigado durante 40 dias. Foram determinados os teores de P disponível extraído pelos diferentes extratores após o período de incubação. Durante o alagamento, foram analisados as concentrações de Fe, P e Ca e o pH na solução do solo. Após 40 dias de alagamento, foi avaliada a produção de matéria seca e a concentração de P na parte aérea das plantas. Os coeficientes de determinação (r2) obtidos entre P acumulado pelas plantas de arroz e o P extraído foram: 0,84 para a Resina de troca iônica (RTA); 0,58 para o Mehlich-1 e 0,61 para o Mehlich-3. Dentre os métodos testados, o método da RTA foi mais eficiente na extração de P do solo para avaliar a disponibilidade de P para a cultura de arroz irrigado em solos adubados com fosfatos naturais. A separação dos solos em grupos, segundo o material de origem e os teores de óxidos de ferro de baixa cristalinidade extraídos com oxalato a pH 6,0, resultou em melhor eficiência de todos os métodos testados para avaliar a disponibilidade de P para o arroz irrigado em solo adubado com fosfato natural reativo
An Assessment of Fire Hazard in the Historic Town of Ouro Preto based on Four Established Analysis Methodologies
This work aims to present a comparison of 4 four analysis methodologies of the fire risks in historical sites These analysis methodologies are the following Ebrafire Chichorro Gretener and Multicriteria The Town area under study is bordered by Tiradentes Square Senador Rocha Lagoa Street Con go Camilo Veloso by street and C nego de Bobadela Street in the historic center of Ouro Preto The comparative analysis among the four methodologies presented discrepancies in the degrees of fire hazards However the block assessed presents a high risk of fire since the great majority of buildings in the area received insufficient fire safety results Therefore although the results here are not conclusive since this research is in the initial phase it is already possible to verify the urgency of mitigation actions to reduce the risk of fire in most buildings in the evaluated bloc
Eficiência do fosfato natural para o arroz irrigado em solo do sul do Brasil
Phosphate rock efficiency to lowland rice was evaluated in a study that we tested: a) phosphorus sources (P): 1- triple superphosphate (TSP); 2-Phosphate rock (PR); and b) phosphorus rates: 0, 10, 20, 40 and 80 mg kg-1. Rice variety EMBRAPA 7 "TAIM", was grown in a pot for thirty days. Soil solution pH values were similar between rates for the same source; however, the PR was superior to TSP in both soil solution sampling. The P concentrations in solution increased according to P rates. P amounts in the second soil solution sampling were similar between rates of the same source, but the differences were observed at P (TST) rate of 80 mg kg-1. Shoot dry matter increased with P rate and the 80 mg kg-1 P rate was superior in both sources. However, the TSP was superior to PR and this tendency was similar with the P in plant tissue and P uptake by plants. P in soil solution, P plant content, P uptake by plants and rice growth increased according to P applied in soil; PR showed high agronomic efficiency at rates over 40 mg kg-1 de P.Com o objetivo de avaliar a eficiência do fosfato natural na cultura do arroz irrigado, foi desenvolvido um experimento onde testou-se: a) fontes de fósforo(P) : 1- Superfosfato triplo (SFT); 2- Fosfato natural (FN); e b) Doses de P: 0, 10, 20, 40 e 80 mg kg-1. Arroz da cultivar EMBRAPA 7 "TAIM", foram cultivadas em vasos durante trinta dias. O pH na solução do solo não diferiu entre as doses na mesma fonte. O P na solução aumentou com o acréscimo das doses de P, porém na primeira coleta não diferiu entre as fontes. Na segunda coleta os teores de P foram similares nas diferentes doses para a mesma fonte, diferindo apenas no SFT na dose de 80 mg kg-1. A produção de matéria seca aumentou conforme a dose de P sendo que a dose de 80 mg kg-1 foi superior nas duas fontes. Os teores de P na solução do solo e na planta, a quantidade acumulada de P e a produção de matéria seca do arroz, aumentaram com o acréscimo das doses de P aplicadas ao solo; o fosfato natural apresentou alta eficiência agronômica a partir de doses equivalentes à 40 mg kg-1 de P
Utilização do granodiorito gnáissico como fonte de potássio na produção de morango/ Utilization of granodiorito gnáissico as potassium source in strawberry production
A produtividade dos frutos do morangueiro é extremamente influenciada pelas práticas de manejo, destacando-se a adubação potássica. A utilização da rochagem pode ser uma alternativa à utilização de adubos químicos solúveis. Dentre as rochas fornecedoras de potássio, destaca-se o granodiorito gnáissico. Em função do exposto, o trabalho foi realizado com o objetivo de avaliar a utilização do granodiorito gnáissico como fonte de potássio para o cultivo do morango. Os tratamentos consistiram das seguintes doses do granodioritio gnáissico: 0; 3; 6; 12; 18 g vaso-1. As características das avaliadas foram as seguintes: produção de frutos; teor de potássio, cálcio e magnésio no tecido vegetal, teor de potássio no solo e teor de potássio no fruto. Os resultados demonstraram que houve uma resposta quadrática da produção de morango às doses de granodiorito gnáissico atingindo uma dose de máxima eficiência técnica de 11,7 g vaso-1. A aplicação do granodiorito gnáissico promoveu aumento nos teores de K no solo, no tecido vegetal e nos frutos do morango. Conclui-se que o granodiorito gnáissico pode ser utilizado como fonte potássica para o cultivo de morango
Produção da cultivar de trevo branco zapican como cobertura verde e sua resposta a utilização de esterco bovino/ Influence of cattle manure on the production and protective quality of olives brs ponteio cultivar
A introdução de espécies exóticas cultivadas no período outono-hibernal tem como objetivo suprir esse vazio forrageiro e manter ou aumentar a capacidade de suporte das pastagens. Além disso, essas espécies podem ser utilizadas como adubos verdes promovendo a melhoria das características físicas, químicas e biológicas do solo em Sistema Plantio Direto. Dentre as espécies com enorme potencial para a utilização como adubos verdes destaca-se o trevo branco, o qual adapta-se bem as condições climáticas da região sul do Brasil. Como desvantagem, o trevo branco apresenta baixa tolerância a solos ácidos e de baixa fertilidade química do solo, como é o caso do sul do Brasil, exigindo correção e adubação para viabilizar seu estabelecimento e sua persistência. Como alternativa a utilização de fertilizantes químicos de custo atual elevado, existe a possibilidade de utilização de insumos orgânicos como o esterco bovino. Em função do exposto, foi realizado um trabalho com o objetivo de avaliar o efeito do esterco bovino sobre a produção do trevo branco utilizado como cobertura verde. Os tratamentos foram constituídos pelas doses de esterco bovino: 0, 37, 74, 111 e 148 T ha-1. No final do estádio vegetativo, a parte aérea do trevo branco foi cortada para a avaliação das seguintes características respostas: produção de massa verde, produção de massa seca e a concentração de nutrientes. Os resultados demonstraram que a produção de massa seca, massa verde e as concentrações de nitrogênio, fósforo e enxofre responderam linearmente as doses de esterco bovino adicionados. Em função dos resultados observados, conclui-se que o esterco bovino é um insumo orgânico que pode substituir alternativamente os adubos químicos solúveis
Relação entre óxidos de ferro e de manganês e a sorção de fósforo em solos no Rio Grande do Sul
Contributions of mean and shape of blood pressure distribution to worldwide trends and variations in raised blood pressure: A pooled analysis of 1018 population-based measurement studies with 88.6 million participants
© The Author(s) 2018. Background: Change in the prevalence of raised blood pressure could be due to both shifts in the entire distribution of blood pressure (representing the combined effects of public health interventions and secular trends) and changes in its high-blood-pressure tail (representing successful clinical interventions to control blood pressure in the hypertensive population). Our aim was to quantify the contributions of these two phenomena to the worldwide trends in the prevalence of raised blood pressure. Methods: We pooled 1018 population-based studies with blood pressure measurements on 88.6 million participants from 1985 to 2016. We first calculated mean systolic blood pressure (SBP), mean diastolic blood pressure (DBP) and prevalence of raised blood pressure by sex and 10-year age group from 20-29 years to 70-79 years in each study, taking into account complex survey design and survey sample weights, where relevant. We used a linear mixed effect model to quantify the association between (probittransformed) prevalence of raised blood pressure and age-group- and sex-specific mean blood pressure. We calculated the contributions of change in mean SBP and DBP, and of change in the prevalence-mean association, to the change in prevalence of raised blood pressure. Results: In 2005-16, at the same level of population mean SBP and DBP, men and women in South Asia and in Central Asia, the Middle East and North Africa would have the highest prevalence of raised blood pressure, and men and women in the highincome Asia Pacific and high-income Western regions would have the lowest. In most region-sex-age groups where the prevalence of raised blood pressure declined, one half or more of the decline was due to the decline in mean blood pressure. Where prevalence of raised blood pressure has increased, the change was entirely driven by increasing mean blood pressure, offset partly by the change in the prevalence-mean association. Conclusions: Change in mean blood pressure is the main driver of the worldwide change in the prevalence of raised blood pressure, but change in the high-blood-pressure tail of the distribution has also contributed to the change in prevalence, especially in older age groups
Worldwide trends in hypertension prevalence and progress in treatment and control from 1990 to 2019: a pooled analysis of 1201 population-representative studies with 104 million participants
Background
Hypertension can be detected at the primary health-care level and low-cost treatments can effectively control hypertension. We aimed to measure the prevalence of hypertension and progress in its detection, treatment, and control from 1990 to 2019 for 200 countries and territories.
Methods
We used data from 1990 to 2019 on people aged 30–79 years from population-representative studies with measurement of blood pressure and data on blood pressure treatment. We defined hypertension as having systolic blood pressure 140 mm Hg or greater, diastolic blood pressure 90 mm Hg or greater, or taking medication for hypertension. We applied a Bayesian hierarchical model to estimate the prevalence of hypertension and the proportion of people with hypertension who had a previous diagnosis (detection), who were taking medication for hypertension (treatment), and whose hypertension was controlled to below 140/90 mm Hg (control). The model allowed for trends over time to be non-linear and to vary by age.
Findings
The number of people aged 30–79 years with hypertension doubled from 1990 to 2019, from 331 (95% credible interval 306–359) million women and 317 (292–344) million men in 1990 to 626 (584–668) million women and 652 (604–698) million men in 2019, despite stable global age-standardised prevalence. In 2019, age-standardised hypertension prevalence was lowest in Canada and Peru for both men and women; in Taiwan, South Korea, Japan, and some countries in western Europe including Switzerland, Spain, and the UK for women; and in several low-income and middle-income countries such as Eritrea, Bangladesh, Ethiopia, and Solomon Islands for men. Hypertension prevalence surpassed 50% for women in two countries and men in nine countries, in central and eastern Europe, central Asia, Oceania, and Latin America. Globally, 59% (55–62) of women and 49% (46–52) of men with hypertension reported a previous diagnosis of hypertension in 2019, and 47% (43–51) of women and 38% (35–41) of men were treated. Control rates among people with hypertension in 2019 were 23% (20–27) for women and 18% (16–21) for men. In 2019, treatment and control rates were highest in South Korea, Canada, and Iceland (treatment >70%; control >50%), followed by the USA, Costa Rica, Germany, Portugal, and Taiwan. Treatment rates were less than 25% for women and less than 20% for men in Nepal, Indonesia, and some countries in sub-Saharan Africa and Oceania. Control rates were below 10% for women and men in these countries and for men in some countries in north Africa, central and south Asia, and eastern Europe. Treatment and control rates have improved in most countries since 1990, but we found little change in most countries in sub-Saharan Africa and Oceania. Improvements were largest in high-income countries, central Europe, and some upper-middle-income and recently high-income countries including Costa Rica, Taiwan, Kazakhstan, South Africa, Brazil, Chile, Turkey, and Iran.
Interpretation
Improvements in the detection, treatment, and control of hypertension have varied substantially across countries, with some middle-income countries now outperforming most high-income nations. The dual approach of reducing hypertension prevalence through primary prevention and enhancing its treatment and control is achievable not only in high-income countries but also in low-income and middle-income settings
Heterogeneous contributions of change in population distribution of body mass index to change in obesity and underweight NCD Risk Factor Collaboration (NCD-RisC)
From 1985 to 2016, the prevalence of underweight decreased, and that of obesity and severe obesity increased, in most regions, with significant variation in the magnitude of these changes across regions. We investigated how much change in mean body mass index (BMI) explains changes in the prevalence of underweight, obesity, and severe obesity in different regions using data from 2896 population-based studies with 187 million participants. Changes in the prevalence of underweight and total obesity, and to a lesser extent severe obesity, are largely driven by shifts in the distribution of BMI, with smaller contributions from changes in the shape of the distribution. In East and Southeast Asia and sub-Saharan Africa, the underweight tail of the BMI distribution was left behind as the distribution shifted. There is a need for policies that address all forms of malnutrition by making healthy foods accessible and affordable, while restricting unhealthy foods through fiscal and regulatory restrictions