scholarly journals Erosion factors and magnetic susceptibility in differet compartments of a slope in Gilbués-PI, Brazil

2013 ◽  
Vol 33 (1) ◽  
pp. 64-74 ◽  
Author(s):  
Hélio L. Santos ◽  
José Marques Júnior ◽  
Sammy S. R. Matias ◽  
Diego S. Siqueira ◽  
Marcílio V. Martins Filho
Keyword(s):  
Magnetic Susceptibility ◽  
Soil Erosion ◽  
Spatial Variability ◽  
Spatial Relation ◽  
Crop Productivity ◽  
Auxiliary Variable ◽  
Topographic Factor ◽  
Significant Difference ◽  
Geostatistical Techniques ◽  
Soil Magnetic Susceptibility

The erosion is the degradation of soil with effects on crop productivity and pollution of the environment. To understand the spatial variability of this phenomenon, geostatistical techniques and concepts of soil-landscape can be used to identify landscape compartments with different potential of erosion. The aim of this study was to understand the factors of erosion in landscape compartments and the relations with the magnetic susceptibility (MS) of the soils in a slope in Gilbués, state of Piauí (PI), Brazil. Sampling meshes were set in compartments I and II with 121 points and in compartment III with 99 points spaced every 10 meters. There was significant difference to erodibility (K) and risk of erosion (RE); the spatial variability of MS was lower than the factors of soil erosion. The soil losses (A), the natural erosion potential (NEP), the RE and the MS had spatial relation with the topographic factor, indicating dependence of the erosion with the relief. We concluded that losses of soil, natural erosion potential and risk of erosion have spatial relation with the topographic factor, showing the dependence of the erosion factors with the relief. The soil magnetic susceptibility can be used as an auxiliary variable in the indirect quantification of the erodibility factor and the risk of soil erosion.

National-scale spatial variations of soil magnetic susceptibility in Brazil

2021 ◽  
Vol 108 ◽  
pp. 103191
Author(s):  
Julierme Zimmer Barbosa ◽  
Giovana Poggere ◽  
Sérgio Henrique Godinho Silva ◽  
Marcelo Mancini ◽  
Antonio Carlos Vargas Motta ◽  
...  
Keyword(s):  
Magnetic Susceptibility ◽  
Spatial Variations ◽  
National Scale ◽  
Soil Magnetic Susceptibility

scholarly journals Impacts of oak deforestation and rainfed cultivation on soil redistribution processes across hillslopes using 137Cs techniques

2021 ◽  
Vol 8 (1) ◽  
Author(s):  
Shamsollah Ayoubi ◽  
Nafiseh Sadeghi ◽  
Farideh Abbaszadeh Afshar ◽  
Mohammad Reza Abdi ◽  
Mojtaba Zeraatpisheh ◽  
...  
Keyword(s):  
Land Use ◽  
Magnetic Susceptibility ◽  
Soil Erosion ◽  
Erosion Rate ◽  
Land Use Changes ◽  
Soil Samples ◽  
Natural Forest ◽  
Oak Forests ◽  
Erosion Rates ◽  
Rainfed Farming

Abstract Background As one of the main components of land-use change, deforestation is considered the greatest threat to global environmental diversity with possible irreversible environmental consequences. Specifically, one example could be the impacts of land-use changes from oak forests into agricultural ecosystems, which may have detrimental impacts on soil mobilization across hillslopes. However, to date, scarce studies are assessing these impacts at different slope positions and soil depths, shedding light on key geomorphological processes. Methods In this research, the Caesium-137 (137Cs) technique was applied to evaluate soil redistribution and soil erosion rates due to the effects of these above-mentioned land-use changes. To achieve this goal, we select a representative area in the Lordegan district, central Iran. 137Cs depth distribution profiles were established in four different hillslope positions after converting natural oak forests to rainfed farming. In each hillslope, soil samples from three depths (0–10, 10–20, and 20–50 cm) and in four different slope positions (summit, shoulder, backslope, and footslope) were taken in three transects of about 20 m away from each other. The activity of 137Cs was determined in all the soil samples (72 soil samples) by a gamma spectrometer. In addition, some physicochemical properties and the magnetic susceptibility (MS) of soil samples were measured. Results Erosion rates reached 51.1 t·ha− 1·yr− 1 in rainfed farming, whereas in the natural forest, the erosion rate was 9.3 t·ha− 1·yr− 1. Magnetic susceptibility was considerably lower in the cultivated land (χhf = 43.5 × 10− 8 m3·kg− 1) than in the natural forest (χhf = 55.1 × 10− 8 m3·kg− 1). The lower soil erosion rate in the natural forest land indicated significantly higher MS in all landform positions except at the summit one, compared to that in the rainfed farming land. The shoulder and summit positions were the most erodible hillslope positions in the natural forest and rainfed farming, respectively. Conclusions We concluded that land-use change and hillslope positions played a key role in eroding the surface soils in this area. Moreover, land management can influence soil erosion intensity and may both mitigate and amplify soil loss.

scholarly journals Magnetic susceptibility for characterizing areas with different potentials for sugarcane production

2016 ◽  
Vol 51 (9) ◽  
pp. 1349-1358 ◽  
Author(s):  
Diego Silva Siqueira ◽  
José Marques Júnior ◽  
Daniel De Bortoli Teixeira ◽  
Sammy Sidney Rocha Matias ◽  
Livia Arantes Camargo ◽  
...  
Keyword(s):  
Magnetic Susceptibility ◽  
Spatial Variability ◽  
Exchange Capacity ◽  
Strongly Correlated ◽  
Soil Attributes ◽  
Sugarcane Production ◽  
Sugarcane Yield ◽  
Chemical Attributes ◽  
Physical And Chemical ◽  
Variability Model

Abstract The objective of this work was to evaluate the use of magnetic susceptibility for characterizing the spatial variability of soil attributes and identifying areas with different potentials for sugarcane (Saccharum spp.) production. Samples were collected at 110 points (1 per 7 ha) in the layers of 0.00-0.20 and 0.20-0.40 m, to determine the magnetic susceptibility and physical and chemical attributes of the soil. Fiber content, sucrose polarization (POL), and sugarcane yield were determined in 33 points. The spatial variability model for magnetic susceptibility was 63 and 22% more accurate in delimiting soil potential for sugarcane production than soil physical and chemical attributes at the 0.0-0.2 and 0.2-0.4-m layers, respectively. The spatial variability map for magnetic susceptibility was strongly correlated with clay (0.83 and 0.89, respectively, for the layers) and sand contents (-0.84 and -0.88); moderately correlated with organic matter (-0.25 and -0.35), sum of bases (-0.46 and 0.37), cation exchange capacity (0.22 and 0.47), pH (-0.52 and 0.13), and POL (0.43 and 0.53); and weakly correlated with sugarcane yield (0.26 and 0.23). Magnetic susceptibility can be used to characterize the spatial variability of soil attributes and to identify areas with different potentials for sugarcane production.

Sign in / Sign up

Export Citation Format

Share Document