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| Tahir,Majid Mahmood; Recous,Sylvie; Aita,Celso; Pfeifer,Ismael Cristiano; Chaves,Bruno; Giacomini,Sandro José. |
| ABSTRACT Isotopic labeling of plants is useful in tracking the fate of carbon (C) from different plant parts in a soil-plant system when these parts decompose simultaneously. Pulse labeling is a relatively simple technique and is amenable for use in the field. Therefore, we evaluated a 13CO2 pulse-labeling method to label crop plants under subtropical field conditions for simultaneous root and shoot decomposition studies. Wheat (Triticum aestivum L.), pea (Pisum sativum L.), and vetch (Vicia sativa L.) plants were grown inside polyvinyl chloride (PVC) cylinders and pulse labeled once a week for a total of 11 times. After harvest, “paired” treatments were designed by combining 13C-labeled shoots with unlabeled roots and unlabeled shoots with 13C-labeled... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: 13CO2; C mineralization; Chemical fractions; Isotopic homogeneity; Plant parts. |
| Ano: 2018 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-06832018000100404 |
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| Pollet,Carolina Schultz; Silva,Leandro Souza da; Chaves,Bruno; Rosa Neto,Lethícia; Dossin,Mariana Ferneda; Giacomini,Sandro José; Cargnelutti Filho,Alberto. |
| ABSTRACT: The state of Rio Grande do Sul has about 20% of the total area as lowland soils, suitable for flooded rice (Oryza sativa). In order to mitigate damage caused by rice monoculture, new crops such as sorghum (Sorghum bicolor) and soybean (Glycine max) have been cultivated in these areas. With different qualities of crop residues, it is expected a change in soil organic matter (SOM) dynamics and consequently, nitrogen (N) availability. The objective of this study was to evaluate the influence of rice, soybean and sorghum crop residues on the N present in physical fractions of SOM of two lowland soils, using labeled 15N technique, under incubation for 180 days in aerobic condition and more 180 days in anaerobic condition. At 30, 180 and 360 days of... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Physical fractionation; Paddy soils; 15N isotope. |
| Ano: 2019 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-84782019000400251 |
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| Redin,Marciel; Recous,Sylvie; Aita,Celso; Chaves,Bruno; Pfeifer,Ismael Cristiano; Bastos,Leonardo Mendes; Pilecco,Getúlio Elias; Giacomini,Sandro José. |
| ABSTRACT Recycling of carbon (C) and nitrogen (N) from plants into soils is decisive for maintaining soil organic matter and soil fertility. Therefore, we quantified plant biomass and C and N in the shoots and roots from the topsoil layer for a wide range of annual crops grown under subtropical conditions. We grew 26 species, 13 main crops, and 13 cover crops, in the field in standard sowing arrangements. Root biomass was recovered from the 0.00-0.20 m soil layer at flowering, and shoot biomass was measured at flowering for all crops and at maturity only for the main crops. Root dry matter (DM) exhibited an average of 14.9 ± 5.7 % of the total shoot biomass at flowering, and the mean shoot DM to root DM ratio was 6.9 (2.8-15.0) for the 26 crops considered.... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Biomass allocation; Cover crops; Fabaceae; Poaceae; Shoot to root ratio. |
| Ano: 2018 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-06832018000100528 |
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| Weiler,Douglas Adams; Giacomini,Sandro José; Aita,Celso; Schmatz,Raquel; Pilecco,Getúlio Elias; Chaves,Bruno; Bastos,Leonardo Mendes. |
| ABSTRACT Cover crops have numerous benefits when used in a no-till system. Understanding the processes of decomposition and N release of summer cover crops (SCC) may help select species and management to be used in cropping systems. This study aimed to evaluate C and N loss of SCC shoots. Six SCCs were evaluated: velvet bean (Mucuna aterrima), pearl millet (Pennisetum americanum), dwarf pigeon pea (Cajanus cajan), sunn hemp (Crotalaria juncea), showy rattlebox (Crotalaria spectabilis), and jack bean (Canavalia ensiformis). The experiment was conducted for two years under no-till in soil classified as Typic Hapludalf (Argissolo). The C and N remaining of crop shoots were evaluated for 140 days using litter bags and the results were fitted with a simple... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Chemical composition; Legumes; Cropping system; Crop residue; Nutrient cycling. |
| Ano: 2019 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-06832019000100414 |
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