Soil carbon prediction in Marajó island wetlands
27/ago/2024
ABSTRACT Soil is an important carbon repository in terrestrial ecosystems, serving a fundamental role in the intricate cycling of this elemental component. Wetlands are crucial components of the global carbon cycle, playing a significant role in carbon sequestration due to their remarkable productivity and unique sedimentary structures. Our study focuses on the wetlands east of Marajó island, recognized as the largest fluvial-marine plain in South America. In this study, we applied a methodological framework to optimize SOC content prediction in […]
Soil legacy data: An opportunity for digital soil mapping
23/jul/2024
ABSTRACT Soil legacy data is past information on soils available from various sources (e.g. survey reports and maps). When compiled and organized, data obtained through historical retrieval can be used as basic input or validation data for digital soil mapping. A bibliometric analysis of this topic can reveal research patterns, evolution, and scientific contribution, thus mapping the science produced in a specific period and determining the trend in research topics based on search terms. This article presents the characterization of […]
Multifractal and joint analysis of soil arthropod diversity in the Brazilian Savanna
12/jul/2024
ABSTRACT Soil fauna organisms participate in a series of processes that benefit the physical and chemical soil properties; however, little is known about their spatial variability and scale. This study aimed to characterize the spatial variability of soil fauna from multifractal and joint multifractal analysis in Brazilian Savanna areas. Pitfall traps collected soil fauna in two Savanna formations (dense Savanna and typical Savanna) in two transects with 128 points. Organisms were identified and classified into functional groups (Microphages, Pollinators, Predators […]
Inversion of soil properties with hyperspectral reflectance in construction areas of high-standard farmland
07/dez/2023
ABSTRACT High-standard farmland construction is an important process that can enhance food security and accelerate new-style modernization agriculture. Hyperspectral remote sensing can provide data and technical support for this type of construction to provide a reference when optimizing high-standard farmland construction areas. This study was performed in Xinzheng City, the primary grain-producing areas in Henan Province. Field sampling and indoor hyperspectral spectroscopy (350~2500 nm) were combined; spectral transformations such as continuum removal (CR) were performed after Savitzky‒Golay (SG) convolution smoothing; […]
Estimation of soil organic carbon content by Vis-NIR spectroscopy combining feature selection algorithm and local regression method
07/dez/2023
ABSTRACT Soil organic carbon (SOC) content is a critical parameter for evaluating soil health. However, high redundancy and invalid information in soil hyperspectral data can reduce the accuracy and stability of SOC prediction models. This study developed a global partial least squares regression (PLSR) model and a local PLSR model for agricultural soils in the LUCAS 2015 database. Some variable selection methods were combined with the regression models and their effects on prediction accuracy were explored. In addition, when the […]
Microstructural changes in Oxisols under long-term different management systems
28/nov/2023
ABSTRACT There has long been a discussion about the effects of soil management on its structure. Since changes can occur due to management and time of use, more accurate assessments can be achieved if carried out in long-term experiments. This study investigated the long-term effects of soil management on the physical quality of a Cerrado Oxisol (Latossolo Vermelho), focusing on microstructural changes. Micromorphology and computed tomography techniques were used to assess the soil’s microstructure. The study compared areas under long-term […]
Reflectance spectroscopy in the prediction of soil organic carbon associated with humic substances
06/jun/2023
ABSTRACT Understanding organic carbon and predominant humic fractions in the soil allows contributes to soil quality management. Conventional fractionation techniques require time, excessive sampling, and high maintenance costs. In this study, predictive models for organic carbon in humic substances (HS) were evaluated using hyperspectral data as an alternative to chemical fractionation and quantification by wet digestion. Twenty-nine samples of Neossolos Flúvicos (Fluvents) – A1, and 36 samples of Cambissolos (Inceptisols) – A2 were used. The samples were also analyzed jointly, […]
Digital soil mapping for the Parnaíba River delta, Brazilian semiarid region
04/abr/2023
ABSTRACT Soil mapping is a permanent demand, but the traditional method does not allow fast execution and low cost. Digital soil mapping (DSM) aims to improve the process by working with models that treat soil spatial variability quantitatively. In this perspective, the objective of the study is to perform DSM of the Parnaíba River Delta, Northeastern Brazil, through the decision tree (DT) integration technique using a set of attributes derived from the digital elevation model (DEM) and satellite images as […]
Spatial multivariate optimization for a sampling redesign with a reduced sample size of soil chemical properties
22/mar/2023
ABSTRACT Precision agriculture can improve the decision-making process in agricultural production, as it gathers, processes and analyzes spatial data, allowing, for example, specific fertilizer application in each location. One of the proposals to deal with spatial heterogeneity of the soil or the distribution of chemical properties is to define application zones (homogeneous subareas). These zones allow reducing both spatial variability of the yield of the crop under study and of the environmental impacts. Considering the soil data, application zones can […]
Identification of plinthite or saprolite residue in soils with high textural contrast in the southern Brazil
12/dez/2022
ABSTRACT Soils classified as Alisols are very frequent in the sedimentary agricultural areas of southern Brazil. The presence of red mottles with morphology similar to plinthite and saprolite residue is very common in these soils, and its identification can be considered a difficult task, both in the field and in the laboratory. The incorrect identification of these redoximorphic features can affect soils’ taxonomic and technical classification. We aimed to compare morphological, physical, chemical and mineralogical data to identify reddish mottles, […]