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Impact of Data Processing and Antenna Frequency on Spatial Structure Modelling of GPR Data.

De Benedetto D, Quarto R, Castrignanò A, Palumbo DA - Sensors (Basel) (2015)

Bottom Line: The results showed that the type and range of spatial structures of GPR data did not depend on data processing at a given frequency.It was also evident that the noise tended to decrease with the complexity of processing, then the most error-effective procedure was selected.The results highlight the critical importance of the antenna frequency and of the spatial scale of soil/subsoil processes being investigated.

View Article: PubMed Central - PubMed

Affiliation: Dipartimento di Scienze della Terra e Geoambientali, University of Bari, Aldo Moro, Bari 70125, Italy. daniela.debenedetto@entecra.it.

ABSTRACT
Over the last few years high-resolution geophysical techniques, in particular ground-penetrating radar (GPR), have been used in agricultural applications for assessing soil water content variation in a non-invasive way. However, the wide use of GPR is greatly limited by the data processing complexity. In this paper, a quantitative analysis of GPR data is proposed. The data were collected with 250, 600 and 1600 MHz antennas in a gravelly soil located in south-eastern Italy. The objectives were: (1) to investigate the impact of data processing on radar signals; (2) to select a quick, efficient and error-effective data processing for detecting subsurface features; (3) to examine the response of GPR as a function of operating frequency, by using statistical and geostatistical techniques. Six data processing sequences with an increasing level of complexity were applied. The results showed that the type and range of spatial structures of GPR data did not depend on data processing at a given frequency. It was also evident that the noise tended to decrease with the complexity of processing, then the most error-effective procedure was selected. The results highlight the critical importance of the antenna frequency and of the spatial scale of soil/subsoil processes being investigated.

No MeSH data available.


(a) The experimental farm (yellow polygon) located in Apulia region (south-eastern Italy) and the experimental test plot delimited by a red rectangle [18]; (b) Pedological pit surveyed in the study area [Reproduced with permission from De Benedetto et al., Geoderma; published by Elsevier, 2012, DOI:10.1016/j.geoderma.2011.05.005].
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sensors-15-16430-f001: (a) The experimental farm (yellow polygon) located in Apulia region (south-eastern Italy) and the experimental test plot delimited by a red rectangle [18]; (b) Pedological pit surveyed in the study area [Reproduced with permission from De Benedetto et al., Geoderma; published by Elsevier, 2012, DOI:10.1016/j.geoderma.2011.05.005].

Mentions: The experiment was conducted at the “Maria Elisa Venezian Scarascia” farm, one of the experimental farms of the Italian Agricultural Research Council (CRA), located in Rutigliano-Bari (40°59′48.25″ N, 17°02′02.06″ E), in south-eastern Italy (Figure 1). The test plot selected for this study was bare soil of 40 m × 20 m size (red rectangle in Figure 1). The study area is located in the Murgia Plateau, characterized by homogeneous sequence of calcareous and dolomitic rocks. Limestones have quite low porosity but are usually fractured and affected by karst dissolution. The soil is classified as fine, mixed, superactive, thermic Typic Haploxeralfs, according to the Soil Taxonomy [14], and as Cutanic Luvisol (Hypereutric, Profondic, Clayic, Chromic), according to the WRB [15]. Soil texture is mainly clayey with the clay content ranging from 30% to 60% by weight increasing in depth and with high content of gravel (15% by weight). The coarse soil mineral fraction increases in volume in the neighbourhood of the outcropping bedrock. The soil depth, as it was also revealed by the pedological survey [16], is rarely deeper than 0.60–1 m, owing to the occurrence of shallow bedrock (Figure 1b). Since high contents of clay may strongly attenuate the signal, a preliminary ERT survey was carried out which allowed us to estimate the resistivity of soil (values between 25 and 60 Ωm) and radar energy attenuation (values between 6 and 14 dB/m). These values show that Ground Penetrating Radar can be effectively and reliably used in this study area. Additional CMP measurements, carried out through a bistatic GPR system with central frequency of 450 MHz, were used to determine velocity profiles [17].


Impact of Data Processing and Antenna Frequency on Spatial Structure Modelling of GPR Data.

De Benedetto D, Quarto R, Castrignanò A, Palumbo DA - Sensors (Basel) (2015)

(a) The experimental farm (yellow polygon) located in Apulia region (south-eastern Italy) and the experimental test plot delimited by a red rectangle [18]; (b) Pedological pit surveyed in the study area [Reproduced with permission from De Benedetto et al., Geoderma; published by Elsevier, 2012, DOI:10.1016/j.geoderma.2011.05.005].
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4541886&req=5

sensors-15-16430-f001: (a) The experimental farm (yellow polygon) located in Apulia region (south-eastern Italy) and the experimental test plot delimited by a red rectangle [18]; (b) Pedological pit surveyed in the study area [Reproduced with permission from De Benedetto et al., Geoderma; published by Elsevier, 2012, DOI:10.1016/j.geoderma.2011.05.005].
Mentions: The experiment was conducted at the “Maria Elisa Venezian Scarascia” farm, one of the experimental farms of the Italian Agricultural Research Council (CRA), located in Rutigliano-Bari (40°59′48.25″ N, 17°02′02.06″ E), in south-eastern Italy (Figure 1). The test plot selected for this study was bare soil of 40 m × 20 m size (red rectangle in Figure 1). The study area is located in the Murgia Plateau, characterized by homogeneous sequence of calcareous and dolomitic rocks. Limestones have quite low porosity but are usually fractured and affected by karst dissolution. The soil is classified as fine, mixed, superactive, thermic Typic Haploxeralfs, according to the Soil Taxonomy [14], and as Cutanic Luvisol (Hypereutric, Profondic, Clayic, Chromic), according to the WRB [15]. Soil texture is mainly clayey with the clay content ranging from 30% to 60% by weight increasing in depth and with high content of gravel (15% by weight). The coarse soil mineral fraction increases in volume in the neighbourhood of the outcropping bedrock. The soil depth, as it was also revealed by the pedological survey [16], is rarely deeper than 0.60–1 m, owing to the occurrence of shallow bedrock (Figure 1b). Since high contents of clay may strongly attenuate the signal, a preliminary ERT survey was carried out which allowed us to estimate the resistivity of soil (values between 25 and 60 Ωm) and radar energy attenuation (values between 6 and 14 dB/m). These values show that Ground Penetrating Radar can be effectively and reliably used in this study area. Additional CMP measurements, carried out through a bistatic GPR system with central frequency of 450 MHz, were used to determine velocity profiles [17].

Bottom Line: The results showed that the type and range of spatial structures of GPR data did not depend on data processing at a given frequency.It was also evident that the noise tended to decrease with the complexity of processing, then the most error-effective procedure was selected.The results highlight the critical importance of the antenna frequency and of the spatial scale of soil/subsoil processes being investigated.

View Article: PubMed Central - PubMed

Affiliation: Dipartimento di Scienze della Terra e Geoambientali, University of Bari, Aldo Moro, Bari 70125, Italy. daniela.debenedetto@entecra.it.

ABSTRACT
Over the last few years high-resolution geophysical techniques, in particular ground-penetrating radar (GPR), have been used in agricultural applications for assessing soil water content variation in a non-invasive way. However, the wide use of GPR is greatly limited by the data processing complexity. In this paper, a quantitative analysis of GPR data is proposed. The data were collected with 250, 600 and 1600 MHz antennas in a gravelly soil located in south-eastern Italy. The objectives were: (1) to investigate the impact of data processing on radar signals; (2) to select a quick, efficient and error-effective data processing for detecting subsurface features; (3) to examine the response of GPR as a function of operating frequency, by using statistical and geostatistical techniques. Six data processing sequences with an increasing level of complexity were applied. The results showed that the type and range of spatial structures of GPR data did not depend on data processing at a given frequency. It was also evident that the noise tended to decrease with the complexity of processing, then the most error-effective procedure was selected. The results highlight the critical importance of the antenna frequency and of the spatial scale of soil/subsoil processes being investigated.

No MeSH data available.