The analysis of the relationship between the electrical conductivity values and the valued soil-ecological units values

Abstract

This article describes the results of the analysis of correlation between the soil electrical conductivity and BPEJ (valued soil-ecological units). The measurements were made in 2006 at the School Agribusiness Land Farm in Lány established by the Czech University of Life Sciences in Prague. The soil electrical conductivity (EC) was measured by the contact method using a sensor with six electrodes. The soil EC data measured were compared with the data obtained from BPEJ maps. The aim was to verify if any relationship exists between the soil EC and BPEJ. The results achieved show that the same dependency exists between the values of the main soil unit of the BPEJ code and the soil EC. The results achieved can be used in the precise agriculture system to improve the decision process. 131and distribute water and also the nutrients near the plants root system. The soil EC is also significantly influenced by the actual soil humidity but, as states Farahani (2007), "Soil water has a strong effect on the values of soil EC, but research shows that even though the values of soil EC may change as soil water changes, the patterns of a soil EC map stay unchanged. Thus, a single soil EC map for a field is probably sufficient for many years to characterize the soil variability patterns. " Doerge et al. (2007) states that the main factors influencing the values of soil EC are pore continuity, water content, salinity level, cation exchange kapacity, and soil depth. MATERIAL AND METHODSIn 2006, the soil EC measurements were made on the selected land "NS KONOPAS A 6001_3" of the School Agribusiness Land in Lány. The contact method was used for the soil EC measurement by means of a traktor-carried measuring frame with six electrodes (Figure 1). The measuring instrument was developed by the Department of Machinery Application, Faculty of Engineering of the Czech University of Life Sciences in Prague. This equipment provides the soil EC values into a measuring central, incl. the position data, in 5 seconds intervals. The position data were obtained by using the GPS unit. The data chains are stored into the .txt format. The BPEJ data were bought in the digital form by the Research Institute for Soil and Water Conservation, Prague-Zbraslav. The ArcView 9.1 software with Geostatistic and Spatial analyst add-in was used for the processing. RESULTS AND DISCUSSIONTwo data sets were used for the analysis, namely soil EC and BPEJ values. Several modifications were performed on the initial data set prior to statistical processing and evaluation. Before the proper elaboration, the voltage and electrical current data, measured by the measuring central, were re-calculated to the soil EC values. Non-complete records were deleted from the basic file, same as the records containing zeros and extreme values. The file modified in this way was then processed by the procedure described in (Thylén et al. 1997;Kumhála et al. 2001). As both authors identically mention, the most failures occur at the moment of driving the machine into a new row,...

Pedogenesis and Variability in Soil Properties in a Floodplain of a Semiarid Environment in Southwestern Sicily (Italy)

“…Correlation between clay content and organic carbon in topsoil. by Mimra et al (2008) in soils from Iran. This is in agreement with the findings of Laura (1974Laura ( , 1975 and Pathak and Rao (1997), who found that C mineralization is inhibited as soil salinity increases, irrespective of the variation in pH (8.1Y10.0).…”

“…The EC outliers represented layers of pedons (CL17 and CL31) characterized by the accumulation of salt as a consequence of morphology, clay percentage, and hydromorphism phase. Salt dynamics are the result of many soil properties, such as clay, sand, and organic carbon content, but above all are influenced by soil humidity (Mimra et al, 2008), so that changes in EC values occur rapidly and are related to climatic and pedoclimatic conditions.…”

“…Clay content was therefore not a good predictor of organic matter in this study. The literature does not provide unequivocal evidence that clays play a role in stabilizing organic matter in soils (Kleber et al, 2005) because in Mediterranean environments, organic matter is often positively related to coarser fraction (Mimra et al, 2008). Tiessen and Stewart (1983), Anderson and Paul (1984), and Christensen and Sorensen (1985) all found that silt-associated C is more stable (less mineralizable and older) than clay-associated C. Furthermore, the amount of clay-associated organic matter is influenced by the type of clay (Barbera et al, 2008) and depends on a series of chemical stabilization processes (Percival et al, 2000).…”

Application of the principle of electroconductivity and the use of EC scanner for determining the properties of the soil

“…The correlation between the measured electrical conductivity of the soil and soil prudential value read from the existing maps was analysed. The results have shown that the correlation is present, and it is therefore concluded that measuring of the conductivity of the soil is proved to be a quick and inexpensive procedure for determining the variability of the soil, whereas prudential value with its reproductive capabilities can be used in precision agriculture as a technical support [13].…”