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Changes in landscape and ecosystem services. Agricultural abandonment and variation in soil organic carbon Soil organic carbon (SOC) contributes to improving the physical, chemical and biological properties of the soil and supply several goods and services of production, regulation and support, which interfere on human health and well-being. This study aim to analyse plant succession processes following the agricultural abandonment and the respective effect on the organic carbon variation in the surface soil layer, in the southern part of Beira Transmontana. The results show that the process of agricultural abandonment promotes an increase in the COS content, which is irrelevant when the vegetation cover is incipient, dominated by herbaceous communities, and more than doubles when there is the establishment of shrub or oak dominated communities (+ 139% and 108%, respectively, compared to soils with arable crops). Despite this increase of carbon in the soil, these communities only contain around half of the SOC obtained for oak woodlands, representative of the native vegetation. Thus, proper soil management, following abandonment, can be a good option to improve its quality and a good strategic measure for carbon sequestration., O carbono orgânico do solo (COS) contribui para melhorar as propriedades físicas, químicas e biológicas do solo e para o fornecimento de bens e serviços vários, de aprovisionamento, regulação ou suporte, que interferem na saúde e bem-estar humano. Com o presente estudo pretende-se analisar os processos sucessão vegetal, na sequência do abandono agrícola, e a respetiva influência na variação do carbono orgânico na camada edáfica superficial, na parte meridional da Beira Transmontana. Os resultados mostram que o processo de abandono agrícola se traduz num aumento do teor de COS, pouco relevante quando coberto vegetal é incipiente, dominado por comunidades herbáceas, mas mais do que duplica quando se verifica a instalação de comunidades arbustivas ou de carvalhal ainda em fase de recuperação (+ 139% e 108%, respetivamente, face aos solos com culturas arvenses de sequeiro). Apesar deste acréscimo de carbono no solo, estas comunidades só contêm aproximadamente metade do valor apurado para o carvalhal representativo da vegetação autóctone. Assim, a gestão adequada do solo, na sequência do abandono, pode constituir, uma boa opção para melhorar a sua qualidade e estratégia para o sequestro do carbono.

Made available in DSpace on 2016-04-01T18:42:52Z (GMT). No. of bitstreams: 0 Previous issue date: 2014. Added 1 bitstream(s) on 2016-04-01T18:49:04Z : No. of bitstreams: 1 S0066-782X2014001900004-en.pdf: 233005 bytes, checksum: f0a6408f6c5e11a1be1062a9f1154d98 (MD5). Added 1 bitstream(s) on 2016-04-01T18:49:04Z : No. of bitstreams: 2 S0066-782X2014001900004-en.pdf: 233005 bytes, checksum: f0a6408f6c5e11a1be1062a9f1154d98 (MD5) S0066-782X2014001900004-pt.pdf: 292894 bytes, checksum: 10574ec6e9d63e20b980b07dca0658bf (MD5) Background: Abdominal obesity is an important cardiovascular risk factor. Therefore, identifying the best method for measuring waist circumference (WC) is a priority. Objective: To evaluate the eight methods of measuring WC in patients with acute coronary syndrome (ACS) as a predictor of cardiovascular complications during hospitalization. Methods: Prospective study of patients with ACS. The measurement of WC was performed by eight known methods: midpoint between the last rib and the iliac crest (1), point of minimum circumference (2); immediately above the iliac crest (3), umbilicus (4), one inch above the umbilicus (5), one centimeter above the umbilicus (6), smallest rib and (7) the point of greatest circumference around the waist (8). Complications included: angina, arrhythmia, heart failure, cardiogenic shock, hypotension, pericarditis and death. Logistic regression tests were used for predictive factors. Results: A total of 55 patients were evaluated. During the hospitalization period, which corresponded on average to seven days, 37 (67%) patients had complications, with the exception of death, which was not observed in any of the cases. Of these complications, the only one that was associated with WC was angina, and with every cm of WC increase, the risk for angina increased from 7.5 to 9.9%, depending on the measurement site. It is noteworthy the fact that there was no difference between the different methods of measuring WC as a predictor of angina. Conclusion: The eight methods of measuring WC are also predictors of recurrent angina after acute coronary syndromes. Key words: Evaluation; Acute Coronary Syndrome; Abdominal Circumference Universidade Estadual Paulista Júlio de Mesquita Filho, Departamento de Clínica Médica, Faculdade de Medicina de Botucatu, Botucatu, Distrito de Rubião Júnior, s/nº, CEP 18618-970, SP, Brasil Universidade Estadual Paulista Júlio de Mesquita Filho, Departamento de Clínica Médica, Faculdade de Medicina de Botucatu, Botucatu, Distrito de Rubião Júnior, s/nº, CEP 18618-970, SP, Brasil

A deficiência de Fe em plantas de café cultivadas em Latossolos ricos em Fe pode ser causada por condições que afetam o transporte deste nutriente no solo, como teores de P, valores de pH elevados e déficit hídrico no solo. O fluxo difusivo do Fe (FFe) em solos foi avaliado como variável de doses de P e de níveis de acidez e umidade. Para isso, amostras superficiais de dois solos, um Latossolo Vermelho distroférrico típico A moderado textura muito argilosa e um Latossolo Vermelho-Amarelo distroférrico A moderado textura média, receberam 20 mg dm-3 de Fe na forma de FeSO4 e, posteriormente, foram submetidas aos tratamentos: sem ou com calagem (para V = 60 %), sem ou com P (500 mg dm-3, na forma de NH4H2PO4) e três níveis de umidade correspondentes aos potenciais: -0,01, -0,04 e -0,1 MPa, constituindo um fatorial 2 × 2 × 2 × 3, com três repetições distribuídas em blocos inteiramente casualizados. Para a determinação do FFe foram montadas câmaras de difusão que receberam uma lâmina de resina de troca catiônica como dreno de Fe. O Fe total adsorvido às lâminas foi extraído após 10 dias de contato com os solos, estimando-se o FFe. Os resultados mostraram que, em ambos os solos, o FFe mostrou-se altamente dependente da umidade e da acidez do solo (calagem) e que, no Latossolo Vermelho distroférrico, foi muito influenciado pela adição de P. O FFe aumentou com a umidade e com a acidez do solo, mas diminuiu com a adição de P no solo mais argiloso, possivelmente pela formação de compostos Fe-P insolúveis neste solo. Iron deficiency in coffee plants cultivated in ferric Latosols may be induced by conditions that affect the transport of this nutrient in soils, such as P concentration, high pH values and low soil moisture content. The iron diffusive flux (FeF) in soils was evaluated as a function of P rates and levels of acidity and moisture. Surface soil samples of a clayey dystroferric Red Latosol and a loamy-sand dystroferric Yellow Red Latosol were supplied with 20 mg dm-3 Fe as FeSO4, and then submitted to the following treatments: absence and presence of liming (60 % of base saturation), absence and presence of P fertilization (500 mg dm-3 as NH4H2PO4) and three moisture levels, corresponding to water potentials of -0.01, -0.04, and -0.1 MPa. Treatments were arranged in a 2 × 2 × 2 × 3 factorial combination, in a complete randomized block design, with three replications. To determine FeF, diffusion chambers were assembled. Each chamber with treated soil received a strip of cation exchange resin that acts as a Fe sink. After 10 days of soil contact, the total Fe adsorbed by the resin strip was extracted and the FeF estimated. Results showed that the FeF was highly dependent on soil moisture and acidity (liming) in both soils and in the clayey ferric Red Latosol it was also greatly influenced by P addition. The FeF increased with soil moisture and acidity, but decreased with P addition in the clayey soil, possibly due to the formation of insoluble Fe-P compounds in this soil.