Tillage system and lime application in a tropical region: Soil chemical fertility and corn yield in succession to degraded pastures

Abstract

The chemical degradation of soils, due to acidity, and erosion processes, resulting from a traditional tillage system method, are one of the main factors responsible for decreasing the productive capacity of tropical pastures. Thus, establishing the crop-livestock integration system (CLIS) by applying lime on surface without disrupting the soil is interest. The objectives of this study were to evaluate the chemical changes in a soil following surface application or incorporation of lime and to determine the effects of liming on plant nutrition, corn (Zea mays L.) grain yields, and various yield components in cultivated areas of degraded Brachiaria decumbens Stapf pasture. A randomized block experimental design with a splitplot arrangement consisting of two management systems (tillage and no-tillage system) and three lime rates (0.0; 2.7 and 5.4 Mg ha À1) was used. The highest reactivity of calcium carbonate was observed after six months of liming, since during the sampling time the level of exchangeable Ca 2+ and Mg 2+ decreased to 0.05 m depth, and increased Al 3+ and soil acidity to 0.3 m. The incorporation of lime did not increase the movement or reaction of the bases in the degraded soil profile. Therefore, surface liming under perennial forage crop residues (B. decumbens Stapf. pasture) provided the best alternative to increase the soil pH index at a depth of up to 0.3 m. Macronutrients uptake by plant, yield components, and corn grain yield were not affected by the application method. However, the use of limestone showed viability to maximize up to 20% in corn productivity, regardless of lime rate. The results suggest that it is possible to ameliorate soil acidity and chemical properties of degraded grassland only by surface application of limestone; however, the strategy is considered effective just for soils with no physical restriction to root development. 2015 Elsevier B.V. All rights reserved.

Does gypsum increase crop grain yield on no‐tilled acid soils? A meta‐analysis

“…As confirmed by the regression tree analysis, gypsum rates >6 Mg ha −1 led to the greatest cereal yields ( Figure 6). This result confirms the linear relationship between gypsum rate and cereal grain yield previously observed in some crops grown on soils with a high Al saturation in the subsoil (Dalla Nora et al, 2017b;Michalovicz et al, 2014;Tiritan et al, 2016). Although the higher gypsum rates resulted in greater increases in grain yield, the crops responded highly variably to gypsum, so the gypsum rate to be used in each case should be established with caution.…”

“…The solid line inside the rectangle represents the median, the dotted line represents the mean, and vertical lines above and below the box extend to the minimum and maximum values, respectively. The mean effect of gypsum application on crop grain yield (Y) is shown above the box plot, and the number of pair observations (n) used to calculate the mean effect is shown at the bottom shown the positive effects of gypsum application on crop grain yield to be stronger under water-deficient conditions (Pauletti et al, 2014;Somavilla et al, 2016;Tiritan et al, 2016). However, water deficiency was present only in 19% of the studies included in this meta-analysis (Figure 1f).…”

“…Nitrogen in well-aerated tropical and subtropical soils is present mainly as NO 3 − , which is readily leached to the subsoil . The more efficient use of available N resulting from gypsum application to an acid subsoil was less marked with soybean because this crop obtains almost all the N it requires by biological fixation Tiritan et al, 2016). In addition, cereal roots usually have a lower root CEC than soybean (Caires, Joris, & Churka, 2011a;Caires et al, 2011b) and hence a lower capacity to absorb cations present at low concentrations in soil (Pauletti et al, 2014;Tiritan et al, 2016).…”

“…The more efficient use of available N resulting from gypsum application to an acid subsoil was less marked with soybean because this crop obtains almost all the N it requires by biological fixation Tiritan et al, 2016). In addition, cereal roots usually have a lower root CEC than soybean (Caires, Joris, & Churka, 2011a;Caires et al, 2011b) and hence a lower capacity to absorb cations present at low concentrations in soil (Pauletti et al, 2014;Tiritan et al, 2016). As a result, the increase in soybean grain yield by the effect of gypsum application was small relative to the cereals and was more limited in the soils with increased Al saturation (>10 and 40% in the presence and absence, respectively, of water deficiency) relative to those bearing the cereals (Al saturation >5%) (Figure 7).…”

“…Although the higher gypsum rates resulted in greater increases in grain yield, the crops responded highly variably to gypsum, so the gypsum rate to be used in each case should be established with caution. Also, high gypsum rates should be applied in combination with liming to prevent Mg 2+ deficiency in the soil surface (Caires, Chueiri, Madruga, & Figueiredo, 1998;Costa & Crusciol, 2016;Soratto & Crusciol, 2008a) and, especially, to neutralize soil acidity in the medium to long term (Bortoluzzi et al, 2014;Fontoura et al, 2019;Joris et al, 2016: Tiritan et al, 2016. In fact, Dalla Nora et al (2017) found gypsum to have more beneficial effects on the subsoil when soil surface acidity was neutralized by liming.…”