Nitrogen and Sulfur Fertilization and Dynamics in a Brazilian Entisol under Pasture
Contribuinte(s) |
UNIVERSIDADE DE SÃO PAULO |
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Data(s) |
18/10/2012
18/10/2012
2010
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Resumo |
Nutrient dynamics in tropical soils sustaining forage grasses are still poorly understood. We conducted a study to evaluate the effect of combined N and S fertilizer rates on the growth of `Marandu` palisade grass [Brachiaria brizantha (Hochst. ex A. Rich.) Stapf], uptake of these elements from the soil by plants, soil organic matter concentration, soil pH, and the mineral and organic fractions of N and S in an Entisol. Combinations of five N rates (0, 100, 200, 300, and 400 g N m(-3)) with five S rates (0, 10, 20, 30, and 40 g S m(-3)) were evaluated in a partial 5 x 5 factorial in a pot experiment, with and without plants. Nitrogen and S were supplied as NH(4)NO(3) and CaSO(4)center dot 2H(2)O, respectively. The N addition in excess did not enhance the palisade grass production due to low plant-available Sin the soil. The supply of low rates of S with N greatly improved the overall N uptake efficiency by the forage plant. The contents of total N, NO(3)(-)-N, and NH(4)(+)-N in the soil varied with N rate and with N uptake by the plants. The association of palisade grass with S fertilization increased the ester-bonded S fraction in the soil. The results suggest that soil residual S could be a potential source of S for plants. Proper N and S fertilizer rates promoted increased grass production due to increased uptake of these nutrients and the dynamics of the organic N and S fractions and mineral fractions in this tropical soil. State of Sao Paulo Research Foundation (FAPESP) Brazilian National Council for Scientific and Technological Development (CNPq) |
Identificador |
SOIL SCIENCE SOCIETY OF AMERICA JOURNAL, v.74, n.4, p.1248-1258, 2010 0361-5995 http://producao.usp.br/handle/BDPI/19232 10.2136/sssaj2009.0228 |
Idioma(s) |
eng |
Publicador |
SOIL SCI SOC AMER |
Relação |
Soil Science Society of America Journal |
Direitos |
restrictedAccess Copyright SOIL SCI SOC AMER |
Palavras-Chave | #SOIL ORGANIC-MATTER #BRACHIARIA-HUMIDICOLA #NITRIFICATION INHIBITORS #TROPICAL GRASS #FRACTIONS #NITRATE #TRANSFORMATIONS #GROWTH #CARBON #PLANTS #Soil Science |
Tipo |
article original article publishedVersion |