Disponibilidade E Recuperação De Nutrientes De Resíduos Culturais Em Solo Com Diferentes Texturas

Teixeira

European J Soil Science

et al. 2021

Understanding the dynamics of decomposition and release of nutrients from plant residues of different covers, in association or succession, is essential to define more sustainable management strategies in tropical soils. The objective of this study was to estimate the decomposition rates and the release of nutrients during the decomposition of different crop residues with different chemical compositions when in association (Mix) or in succession as residue management. A study was carried out with the respective treatments in a (2 Â 6) + 1 factorial scheme: (a) without and with the addition of Pennisetum americanum residue (L); and (b) six residue crops (legumes and non-legumes) and one additional treatment with residue of millet only; with destructive samples over time (0; 0.08, 0.25 and 0.41 years after incubation). The treatments were distributed in a randomized block design with four replicates. The plant material was processed, and the contents of macro-and micronutrients were determined. The decomposition rates and release of nutrients from the residues were estimated by fitting nonlinear regression models. Residues of only non-legumes, with the exception of sunflower, tend to accumulate and degrade more slowly, resulting in a slow release of nutrients to the soil. Legume residues are more easily decomposed, enabling faster delivery of the nutrients available to the soil. Despite the faster degradation of legume residues, brown hemp was more resistant to decomposition. A combined supply of legume and non-legume residues favoured a diversified pattern of decomposition and release of nutrients among the different residues studied. The knowledge of

Section: Discussionmentioning

confidence: 99%

Decomposition and nutrient release from legume and non‐legume residues in a tropical soil

Teixeira

European J Soil Science

et al. 2021

“…The utilization of soil potassium depends on the texture and may be higher in sandy soils due to the lower buffering capacity of K, as expressed by the CEC (Medeiros et al, 2010;Maluf et al, 2015). The soil porous system is mainly altered by machine traffic, a fact that did non-existen in this study.…”

Section: Attributesmentioning

confidence: 83%

Chemical and physical attributes of five Oxisols as predictors of shoot dry mass of white oats

2021

In no-tillage systems, oats are one of the species most used as a cover crop in the subtropical region of Brazil. This study aims is to determine a set of chemical and physical properties of five Oxisols after surface liming, and to determine whether these properties are related to the shoot dry mass production of white oat (Avena sativa L.) variety IPR Aphrodite, in order to establish a model to predict its yield. For this purpose, a field experiment was conducted during 2015 and 2016 in Londrina County in the State of Paraná with samples of B horizon collected from five Oxisols with clay content ranging from 15-80 dag kg -1 arranged in microplots since 2004. Soil pH in CaCl 2 , calcium, magnesium, potassium, potential cation exchange capacity (CEC), base saturation, microporosity, total porosity, field capacity, permanent wilting point, clay and sand of the Oxisols were the parameters that most influenced the dry mass production of white oats. Oxisol extrinsic factors such as values pH and base saturation, as well as the calcium and magnesium contents, positively altered with surface liming, boosting the production of oat dry mass production.

“…A taxa de recuperação do P aplicado via fertilizante (TR) foi calculada com a seguinte fórmula: TR (%) = (P acumulado nas plantas adubadas -P acumulado nas plantas sem adubação com P) / Dose de P aplicada × 100 (Maluf et al, 2015).…”

Section: Methodsunclassified

Influência do vigor de sementes na resposta do fejoeiro à adubação com fósforo

Fariña

Franco

Aquino

et al. 2022

RSD

Sementes de alto vigor resultam em melhor estabelecimento da planta e podem com isso melhorar o aproveitamento de nutrientes, especialmente do fósforo (P). Desta forma, objetivou-se avaliar o crescimento e absorção de P pelo feijoeiro em função do vigor das sementes em solos de texturas contratantes. Os tratamentos foram montados em esquema fatorial 2x5, combinando alto e baixo vigor de semente com cinco doses de P que foram 0, 35, 70, 140 e 280 mg dm-3 em solo de textura média e de 0, 50, 100, 200, 400 mg dm-3 em solo argiloso. Foram cultivadas quatro plantas do cultivar Dama em vasos contendo 5 dm3 de solo e avaliadas até início de floração. Sementes de alto vigor resultaram em incremento da matéria seca da planta (parte aérea + raiz) de 11 e 15% nos solos de textura media e argiloso, respectivamente. A fotossíntese aumentou nas plantas originadas de sementes de alto vigor em 26,04% no solo de textura media, mas foi similar entre as plantas de sementes de alto e baixo vigor no solo argiloso. A dose de P necessária para alcance de pelo menos 95% da máxima fotossíntese foi 46% maior nas plantas originadas de sementes de baixo vigor. O acúmulo de P das plantas de sementes de alto vigor cultivadas em solo de textura média foi 37% maior do que as de baixo vigor. No solo argiloso não houve esta diferença, no entanto, a dose de P no solo para o alcance do máximo acúmulo foi menor quando as sementes foram de alto vigor. A taxa de recuperação do P foi maior em plantas originadas de sementes de alto vigor nos dois solos. Conclui-se que as plantas oriundas de sementes de alto vigor apresentam maior crescimento e acúmulo do P o que evidência a importância da utilização de sementes de alto vigor para o maior aproveitamento das adubações fosfatadas no feijoeiro.