Management of marandu grass pasture increases soil carbon and nitrogen stocks in silvopastoral systems in the Brazilian Cerrado
12/dez/2024
ABSTRACT Integration of systems with pastures, using silvopastoral systems, can increase soil carbon levels, optimize land use, improve the quality and productivity of agricultural products, and promote the conservation of environmental resources. This study aimed to evaluate the influence of management practices of marandu grass at eucalyptus shading levels in a silvopastoral systems, on organic carbon and nitrogen stocks, and soil chemical properties in the Brazilian Cerrado. Environments with different light availability in the plots (SPS 55-60, SPS 50-55, SPS […]
Differences between Pseudobombax grandiflorum and Bauhinia forficata in terms of responsiveness and dependence to mycorrhiza
25/nov/2024
ABSTRACT The benefits promoted by arbuscular mycorrhizal fungi (AMF) to forest species seedlings include higher growth rate, better nutrition, and higher survival rates. Inoculation with AMF may facilitate revegetation of degraded lands, although it depends on symbionts and environmental conditions, such as soil P availability. In this sense, the lack of information justifies the carrying out of studies of this nature. We investigated the dependence and responsiveness of two forest species native to the Atlantic Forest, Pseudobombax grandiflorum and Bauhinia […]
Critical levels and fertility classes of soils with high-activity clay in the Brazilian semi-arid region
04/nov/2024
ABSTRACT Soil fertility evaluation is important for adopting conservation management and adequate nutrient supply. The objective of this study was to identify critical levels and soil fertility classes using the boundary line method for rainfed crops (corn, cowpea and sabiá [Mimosa caesalpiniifolia]) in the Brazilian semi-arid region. A database of 226 soil fertility analyses of samples from the 0.00-0.20 m soil layer, and corn, cowpea and sabiá yields from Ceará State was used to generate interpretation classes (at 80 and […]
Potassium distribution in soil profiles under no-tillage system
11/out/2024
ABSTRACT Potassium (K) vertical mobility in soils has often been overestimated and used as a rationale for recommending the broadcast application of this nutrient in fertility management programs, especially in soils with low cation exchange capacity (CEC). This study aimed to evaluate the vertical distribution of K in two land uses: areas with natural vegetation and crop fields managed under no-tillage (NT) fertilized with K. For this purpose, 49 soil profiles from the Brazilian subtropical state of Rio Grande do […]
Use and recovery of P reserves in Southern Brazil Oxisols under no-till with low and high P availability
10/set/2024
ABSTRACT The accessibility of soil P reserves by plants on highly weathered Brazilian soils remains unclear. In this study, we assessed the contribution of soil P fractions to P uptake by soybean plants in two no-till Oxisols (Latossolos), with low and high initial content of available P. The recommended P rates (viz., 153 and 50 kg ha-1 yr-1 in the low-P and high-P soil, respectively) were applied in the form of triple superphosphate (TSP) or Bayovar rock phosphate (BRP) plus […]
Bone char: characterization and agronomic application as an alternative source of phosphorus
27/ago/2024
ABSTRACT Alternative materials can be used to reduce reliance on mining for P-based fertilizers. In this sense, the pyrolysis process of bovine bones produces the “bone char”, which can be used as a source of P. This study aimed to characterize bone char and conduct a comparative analysis with both soluble (triple superphosphate) and non-soluble (Bayóvar phosphate rock) phosphate fertilizers, specifically examining its behavior in soil and uptake by plants. Bone char characterization was performed by X-ray diffraction (XRD), attenuated […]
Forage and macronutrient accumulation in grass-legume intercropping in a warm climate
26/jul/2024
ABSTRACT Diversifying pastures with forage legumes may reduce nitrogen fertilization due to biological N fixation. This study aimed to quantify forage accumulation rate and macronutrients extraction and to identify the best intercropping combination between butterfly pea (Clitoria ternatea) – a legume, and three warm-season forage grasses of different growth habits (signalgrass – Urochloa decumbunes, Guinea grass – Mega thyrsus maximus, and bermudagrass Cynodon dactylon). Treatments consisted of mixes of perennial herbaceous legume, butterfly pea (twining stem), with grasses, signalgrass (decumbent […]
Seasonal variation of nutrients in macaw palm (Acrocomia aculeata) leaves and sampling time definition
10/jun/2024
ABSTRACT Macaw palm (Acrocomia aculeata) is a widespread tree in Brazil, and the oil industry has been increasing interest in this tree due to its high oil concentrations, rusticity, and adaptability to different environments. Currently, macaw palms are being domesticated and are in an early rational cultivation process. Foliar diagnosis can contribute to managing fertilization, but there is no protocol for leaf sampling. This study aimed to evaluate the seasonal variation of leaf nutrient contents and indicate an adequate period […]
Garlic yield after decomposition and nutrient release of cover crops under no-tillage and conventional tillage
31/maio/2024
ABSTRACT Garlic (Allium sativum) is normally grown under conventional tillage (CT) with soil being excessively mixed by plowing and harrowing operations that degrade soil structure, increase production costs, and increase environmental contamination. Alternatively, cover crops can be grown and their residues placed on soil surface, enabling garlic to be grown under no-tillage (NT) system. However, for subtropical climate there is little information on the impacts of tillage systems and cover crop species, particularly of their decomposition process and nutrients release, […]
P-chromophore stability of Mehlich-1 and Mehlich-3 under Braga & Defelipo or Murphy & Riley dosing methods
08/maio/2024
ABSTRACT The performance of colorimetric methods for P quantification has been overlooked by researchers for decades. We investigated the performance of two blue colorimetric methods for P quantification, Braga and Defelipo (B&D) and Murphy and Riley (M&R), using two commonly soil P extractants, Mehlich-1 (M1) and Mehlich-3 (M3). Specifically, we evaluated the color development time and its stability in different soil extractant solution proportions (1:1 or 1:4 v/v), the optimum wavelength, limits of detection, and element quantification. Our results indicate […]