Nitrogen and Sulfur Fertilization and Dynamics in a Brazilian Entisol under Pasture

Abstract

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 × 5 factorial in a pot experiment, with and without plants. Nitrogen and S were supplied as NH4NO3 and CaSO4·2H2O, respectively. The N addition in excess did not enhance the palisade grass production due to low plant‐available S in 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, NO3−–N, and NH4+–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.

Soil sulfur fractions dynamics and distribution in a tropical grass pasture amended with nitrogen and sulfur fertilizers

“…2A). Similarly to previous studies of different grasses (Kalmbacher et al, 2005;Salvagiotti et al, 2009;De Bona and Monteiro, 2010), our data show that plant responses to S application enhanced Nuse efficiency.…”

“…Approximately 55% of the 172 million ha of grassland in Brazil consists of Brachiaria. These grasses are highly productive rhizomatous perennial plants that can respond well to S and N fertilization (De Bona and Monteiro, 2010). The forage responses to S and N fertilization have been extensively reported for other species such as bahiagrass (Paspalum notatum Fluegge): Kalmbacher et al (2005); oat (Avena sativa L.): Wang et al (2002); and ryegrass (Lolium sp.…”

Speciation of Sulfur in Biochar Produced from Pyrolysis and Gasification of Oak and Corn Stover

“…14,15 Sulfur deficiency is a problem that has been reported recently. 16 Numerous studies have shown indirectly that the addition of biochars to soils could increase soil sulfur bioavailability.…”

The quality of sulphur selected fractions in soil from Nature Reserve Žitavský Luh

“…The smallest ratio the content of total organic carbon and selected sulphur fraction were the soil type Mollic Fluvisol (Figure 3; depth >0.65 m; C : SS = 16 : 1; C : ClSS = 26 : 1; C : HSS = 17 : 1). Despite the fact that plants absorb S mainly as sulphate, organic S (S directly bonded to C and ester S) pools are important sources of S to plants during their growing season (De Bona and Monteiro, 2010;Freney et al, 1975;Goh and Pamidi, 2003;McGill and Cole, 1981). The process of transformation of organic S to inorganic sulfate (mineralization) and the reverse process (incorporation of sulfate into soil organic compounds or immobilization) play important roles in the cycling of S within the soil and are microbiologically mediated (Kertesz and Mirleau, 2004).…”