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Author: Silvio Vasconcelos de Paiva Filho, Rose Luiza Moraes Tavares, Camila dos Santos Ferreira, Túlio Porto Gonçalo, João Fernandes da Silva Júnior
Year: 2021
Keywords: agregados do solo; porosidade; Urochloa
ABSTRACT:
Soil chiseling conducted only in the planting row is a minimal-disturbance soil management practice used for soil preparation in sugarcane plantations. However, the impacts of this practice on soil physical quality need to be evaluated through agricultural experimentation. The objective of this study was to evaluate the physical quality of an Ultisol submitted to chiseling as part of sugarcane management. The treatments consisted of soil chiseling only in the planting row (CPR) and chiseling in the total area of the soil (CTA). After soil preparation, the planting rows that were submitted to chiseling had better soil physical quality than did the area between the rows that did not receive chiseling in site preparation due to greater pore volume and lower PR and BD. However, the beneficial effect of chiseling did not persist due to subsequent soil reconsolidation, and disappeared soon after the planting of sugarcane, and remained this way up to the post-harvest period wherein the areas within (CPR) and between (CTA) the planting rows had equal soil physical quality. Because of this, the yield of stalks between the two treatments were similar, with an average yield of 110 t ha−1.Reconhecidas pelo desempenho do sistema radicular, forrageiras do gênero Urochloa spp. são espécies que melhoram os atributos físicos do solo. Nesta perspectiva, o objetivo deste trabalho foi caracterizar propriedades físicas de um Latossolo Vermelho sob diferentes espécies forrageiras do gênero Urochloa no município de Rio Verde – GO. O ensaio foi conduzido a campo, no período de entressafra, com plantio em faixas das espécies Urochloa brizantha cv. Paiaguás, Urochloa ruziziensis e Urochloa brizantha cv. Marandú. Ao final do ciclo das Urochloas, foram coletadas amostras de solo para avaliações de densidade, porosidade, textura, diâmetro médio ponderado e geométrico, Índice AGRI, resistência à penetração e umidade do solo, além de peso seco da raiz. O modelo experimental utilizado foi parcelas divididas e para interpretação de resultados, a análise de componentes principais. As espécies Urochloas brizantas (Paiaguás e Marandú) apresentaram maior potencial para formação de agregados do solo. O peso seco de raízes foi o parâmetro que mais explicou a variância causada pelas diferentes Urochloas.
Author: Daniel Pereira Pinheiro, Nilvan Carvalho Melo, Carolina Fernandes
Year: 2021
Keywords: Ultisol; Saccharum sp; Factor analysis
ABSTRACT:
Soil chiseling conducted only in the planting row is a minimal-disturbance soil management practice used for soil preparation in sugarcane plantations. However, the impacts of this practice on soil physical quality need to be evaluated through agricultural experimentation. The objective of this study was to evaluate the physical quality of an Ultisol submitted to chiseling as part of sugarcane management. The treatments consisted of soil chiseling only in the planting row (CPR) and chiseling in the total area of the soil (CTA). After soil preparation, the planting rows that were submitted to chiseling had better soil physical quality than did the area between the rows that did not receive chiseling in site preparation due to greater pore volume and lower PR and BD. However, the beneficial effect of chiseling did not persist due to subsequent soil reconsolidation, and disappeared soon after the planting of sugarcane, and remained this way up to the post-harvest period wherein the areas within (CPR) and between (CTA) the planting rows had equal soil physical quality. Because of this, the yield of stalks between the two treatments were similar, with an average yield of 110 t ha−1.
Author: João Fernandes da Silva Júnior, Diego Silva Siqueira, Daniel De Bortoli Teixeira, Alan Rodrigo Panosso, José Marques Júnior, Gener Tadeu Pereira
Year: 2021
Keywords: Pedological cartography; Mahalanobis distance; Pedology; Pedometrics; Digital soil mapping; Soil survey; Geomorphology; Tropical soils
ABSTRACT:
Multivariate split moving window (MSMW) is a tool to automate soil mapping and to assess uncertainty in soil boundaries. In this paper, we propose a new approach to locate soil boundaries. We investigated the potential of (i) MSMW associated with Mahalanobis D2 and (ii) split moving window (SMW) associated with magnetic susceptibility (MS) as tools for validation of soil boundaries. A transect was lined in Guatapara city (Sao Paulo state, Brazil), and 172 soil samples were collected from 86 locations, at a depth of 0–25 and 25–50 cm, for physical and chemical analyses. Additionally, categorical properties – geology, land use, and altitude – were assessed at the same sampling points. All the data were organized into four groups of properties (G1, G2, G3, and G4) and analyzed by principal component analysis, MSMW analysis – to delineate map units using D2 –, and SMW analysis using MS. MSMW and SMW were compared regarding their potential to locate soil boundaries along the transect. The MS peaks in SMW presented a correlation with peaks of t-statistics and D2 in MSMW: (r = 0.56; p < 0.01 – r = 0.69; p < 0.01) and (r = 0.55; p < 0.01 – r = 0.64; p < 0.01) for both depth intervals (0–25 cm and 25–50 cm), respectively. MSMW was more sensitive than SMW in the detection of soil boundaries in areas with lower clay content. Compared to conventional soil surveys, MSMW considerably improved the prediction of boundaries in mapping units. We concluded that the proposed method is a promising strategy for soil surveyors and can be used to assist pedological cartography.
Author: Ranier Vieira Ferreira, Rose Luiza Moraes Tavares, Sandrielle Furquim de Medeiros, Alessandro Guerra da Silva, João Fernandes da Silva Júnior
Year: 2020
Keywords: cerrado; latosols; organic; matter
ABSTRACT:
The use of no-till conservationist agricultural systems as well as intercropping in the Cerrado biome are practices that increase soil organic matter (SOM) due to the deposition of straw. This study aimed to quantify the carbon stock and organic fractions of a latosol under off-season monoculture (Sorghum bicolor and Urochloa ruziziensis) and intercropping (S. bicolor-U. ruziziensis) systems, in Rio Verde, state of Goiás, Brazil. Soil samples were collected from different layers: 0-10, 10-20 and 20-40 cm. The following variables were determined: organic carbon content, carbon stock, dry matter and fractions of organic matter (labile and mineral). The results showed that the organic fractions of the soil are modified according to the adopted management. Intercropping of S. bicolor and U. ruziziensis increased the carbon stock, with the presence of more labile organic fractions on the soil surface, while the use of U. ruziziensis enhances the production of recalcitrant organic fractions, promoting greater preservation of the soil organic matter.
Author: João Fernandes da Silva Júnior, Thiago Thome da Silva, Devid Jackson da Silva Sousa, Rose Luiza Moraes Tavares, Benedito Dutra Luz de Souza, Daniel Pereira Pinheiro
Year: 2024
Keywords: Precision agriculture, geostatistics, site-specific management, multivariate analysis, spatial modeling
ABSTRACT:
In precision agriculture, accurate delineation of management zones and understanding spatial variability of soil properties and crop yields are critical for optimizing resource allocation and improving productivity. Spatial variability of different environmental factors (soil and plants) is evident in
several studies. Associations between the texture and chemical properties of the soil and cowpea yield have been tested, but a large, unexplained variance of ranges between kriged maps is usually reported. This suggests that a deeper exploration into the soil
properties of these spatial interactions may help develop our understanding on how to reduce the number of soil property maps to delineate management zones and simplify interpretation. The main objective of this study was to investigate whether factorial kriging analysis can be used as an auxiliar
variable to cokriging of soil properties and cowpea yield, and what is the potential of spatial Fuzzy C-Means associated with factorial kriging analysis
to delineate management zones. This study employed factor maps and spatial clustering to classify the cowpea field into two management zones based on a multivariate and geostatistical analysis using soil texture and chemical properties. From Farmer, 66 soil samples were collected at a depth layer
of 0.00-0.20 m, at points with a regular spacing of 12 m, at Millennium Farm in the municipality of Tracuateua, Pará State, to make the technology
applicable to the most common data available to farmers. It also used spatial Fuzzy C-Means to generate estimated maps. Only the kriged maps of soil properties were inefficient in delineating management zones. Factor maps and spatial Fuzzy C-Means were efficient in delineating the
two management zones. Factorial kriging analysis can be used in cokriging to estimate soil properties and
the cowpea field. The proposed method is a practical tool to delineate management zones, performing better and more efficiently compared with soil multiple property maps. The optimal number of management zones for cowpea cultivation was determined to be two. This encompasses soil management, yield considerations, and site-specific choices, all aimed at mitigating the impacts of precision agriculture on high
productivity.
Author: Iolanda Maria Soares Reis, Suelen Cristina Nunes Alves, Wanderley José de Melo, Laércio Santos Silva, Ludmila de Freitas, Ivanildo Amorim de Oliveira, Ianna Bizerra Barros, Gabriel Maurício Peruca de Melo, Valéria Peruca de Melo.
Year: 2019
Keywords: Bioaccumulation; Heavy metal; Pollution; Productivity; Soil science
ABSTRACT:
The use of sewage sludge as fertilizer is a widespread practice. However, the presence of heavy metals and pathogens in sludge are a cause for concern. The objective of this study was to determine the levels of cadmium (Cd), copper (Cu), and chromium (Cr) in leaves, aerial parts, and kernels of maize grown in red latosol that was fertilized with sewage sludge for 15 consecutive years. Metal concentrations in soil and kernel yield were also determined. A randomized block design was used, with five replicates and four treatments: T1, mineral fertilization (control); T2, application of sewage sludge at 5 Mg ha−1; T3, application of sewage sludge at 10 Mg ha−1; and T4, application of sewage sludge at 20 Mg ha−1. All plots received potassium (K) supplementation. Fertilization with sewage sludge was as efficient as mineral fertilization. Sewage sludge had no negative effect on kernel yield. A negative correlation was observed between metal concentrations in soil and plant samples. Cd was detected at ≤0.04 mg kg−1 in kernels and Cu at ≤2.34 mg kg−1, whereas Cr was not detected in any sample. These levels are considered safe for human consumption, according to the Brazilian Health Regulatory Agency. Fertilization with sewage sludge for 15 years did not increase Cu, Cd, and Cr levels in the soil and had no negative effect on maize, which shows the potential of sewage sludge for agricultural use.
Author: Patrícia Gabarra Mendonça, Daniel De Bortoli Teixeira, Mara Regina Moitinho, João Fernandes da Silva Júnior, Ismênia Ribeiro de Oliveira, Marcílio Vieira Martins Filho, José Marques Junior, Gener Tadeu Pereira
Year: 2018
Keywords: green cane; burnt cane; geostatistics; indicator kriging
ABSTRACT:
The identification of erosion-susceptible areas is fundamental for the adoption of soil conservation practices. Thus, the best way to estimate the spatial pattern of soil erosion must be identified, in which the process uncertainties are also taken into consideration. The purpose of this study was to evaluate the spatial and temporal uncertainty of soil loss under two scenarios of sugarcane harvest management: green cane (GC) and burnt cane (BC). The study was carried out on a 200-ha area, in Tabapuã, São Paulo State, Brazil. A regular 626-point sampling grid was established in the area, with equidistant intervals of 50 m and a final plant density of about 3.3 samples per ha. The probability that the soil loss would exceed the tolerable limit of 6.67 t ha-1 yr-1 was estimated for each management scenario and after the five harvests. The temporal uncertainty was determined by integrating the estimated annual probabilities, representing the harvests. Areas with soil loss risks above the threshold were identified based on probability maps, generated from the individual and combined dichotomous variables. Soil losses from the BC were highest, during all five harvests. With the exception of the 5th harvest and the entire cultivation cycle under GC, all soil loss estimates were spatially dependent. From the 4th harvest under GC, the probability of the soil loss exceeding the threshold was above 80 % in zero percent of the area, whereas, for BC, the probability exceeded 80 % in 40 % of the area. The production cycle allowed the delimitation of priority areas for the adoption of conservation practices in each management. In the BC, areas with steeper slopes were more likely to exceed the threshold with lower uncertainties.
Author: José Roberto Brito Freitas, Daniel De Bortoli Teixeira, Mara Regina Moitinho, João Fernandes da Silva Júnior, Diego Silva Siqueira, Bruno Flávio Figueiredo Barbosa, Pedro Luiz Martins Soares, Gener Tadeu Pereira
Year: 2019
Keywords: nisotropia; geoestatística; nematoides
ABSTRACT:
O nematoide das lesões radiculares, Pratylenchus brachyurus, é autóctone da região dos cerrados do Brasil. Embora a cultura da soja não seja hospedeira natural do mesmo, o avanço desta sobre áreas do Cerrado, fez com que o nematoide se tornasse um importante patógeno para a cultura. Neste estudo, objetivou-se avaliar a distribuição espacial de P. brachyurus e sua influência na produtividade da cultura da soja no Leste do Maranhão. Para tal, foi conduzida uma amostragem em 142 pontos georreferenciados distribuídos em uma área de 180 × 180 m. Foram coletadas amostras de planta e solo, sendo os nematoides extraídos e contados. Os padrões espaciais foram estimados utilizando análises geoestatísticas. Modelos exponenciais anisotrópicos foram ajustados para todas as variáveis estudadas com alcances maiores na direção do preparo do solo e plantio (135º). O aumento da população de nematoides, bem como seu padrão espacial, relacionou-se com a presença de raízes da planta hospedeira no solo. A direção do preparo do solo e plantio da cultura influenciaram na distribuição dos nematoides na área, sendo o principal fator controlador do padrão espacial dos mesmos.
Author: Mara Regina Moitinho, Milton Parron Padovan, Elton da Silva Bicalho, Antonio Sergio Ferraudo, Daniel De Bortoli Teixeira, Angélica Santos Rabelo de Souza Bahia, Daniel Pereira Pinheiro, Llerme Navarro Vasquez, Newton La Scala Jr.
Year: 2019
Keywords: Soil respiration, Soil attributes, Saccharum spp. Multivariate analysis
ABSTRACT:
Agriculture is a great emission source of CO2 into the atmosphere, contributing significantly to the greenhouse effect. Considering the hypothesis that there are differences in soil carbon dynamics due to the distinct physiological and morphological characteristics of sugarcane cultivars, the aim of this study was to characterize the short-term soil CO2 emission associated with soil attributes in agricultural areas under cultivation of five sugarcane cultivars. The experiment was conducted in an area of high-clay Oxisol (Hapludox, USDA Soil Taxonomy) located at the Cerrado biome, Midwestern region of Brazil. Over the course of 20 days, ten measurements of soil CO2 emission (FCO2), soil temperature (Ts), and soil moisture (Ms) were carried out. Subsequently, soil samples were collected at a depth of 0–0.20 m to determine soil physical and chemical attributes. In timescale, FCO2, Ts, and Ms varied depending on the amount of straw produced by each cultivar. The cultivars RB935608, RB935744, and SP832847 induced a higher soil CO2 emission since they are associated with controlling factors of the primary CO2 production process (higher organic matter content and lower C/N ratio in the soil). Thus, strategies to reduce greenhouse gas emissions in agriculture, such as the choice of sugarcane cultivars that provide lower soil CO2 emissions, are essential to mitigate important environmental issues such as the global warming.
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