Depth distribution of available micronutrients in cultivated soil

Abstract

This paper presents a study of the profile distribution of available micronutrients Fe, Mn, Cu and Zn and radionuclide 137 Cs in cultivated soil at the experimental field "Radmilovac" (property of Agricultural Faculty, Belgrade University) in the vicinity of Vinĉa Institute of Nuclear Sciences. The soil belongs to the anthrosol class of anthropogenic soils according to FAO (2006). At first, the deep plowing was performed while preparing soil for planting peach trees followed by cultivation of soil for 12 years. All agricultural treatments at the experimental field ceased for three years. After that period, soil sampling was carried out. Contents of DTPA-extracted Fe, Mn, Cu and Zn were in the range of (mg kg -1 ): 5.8-41.6; 9.2-34.2; 1-7.6 and 0.2-1.3, respectively. Detected activity concentration (Bq kg -1 ) for 137 Cs ranged from 1.8 to 35. It was noticed that distribution patterns of 137 Cs radionuclide and available Cu and Zn along soil depth were very similar and they were analyzed by simple linear regression; mutual affinity for the soil organic matter might affect their distribution in soil. Contents of available Fe and Mn exhibited different, more constant distribution within a soil horizon.

<b>Effect of liming on micronutrient availability to soybean grown in soil under different lengths of time under no tillage

“…The extractable soil Zn in the six-year NT soil did not vary with depth, thus disagreeing with previous results obtained (Castro, Camargo, Cantarella, Vieira, & Dechen, 1992;Edwards et al, 1992;Teixeira et al, 2003;Vukasinovic et al, 2015). In contrast, the extractable soil Zn in the site with three years under NT was almost always lower in the deepest layer evaluated.…”

“…The highest extractable soil Mn was found in the surface layers, in agreement with the results reported by other authors (Martin-Rueda et al, 2007;Vukasinovic et al, 2015). However, this portion of the soil showed the highest pH (Moreira et al, 2001).…”

“…In the study, the lower extractable soil Cu was attributed to the presence of more OM on the surface, thus resulting in more complexation of the element (Fageria et al, 2002). In the present work, correlation coefficients between the extractable soil Cu and OM were also low or non-significant (data not shown); these results are in disagreement with results by many authors for NT soils (Teixeira et al, 2003;Santiago et al, 2008;Martin-Rueda et al, 2007;Vukasinovic et al, 2015). However, extractable soil Cu is mostly governed by OM in many soils because it can form complexes and chelates with a large portion of the soil Cu 2+ (Tisdale et al, 1985).…”

“…According to Follett and Peterson (1988), the accumulation of both OM and water close to the surface may decrease the soil redox potential and thus increase the Fe availability to crops. In many cases, the high exchangeable Fe content in the surface layers of the soil is related to the higher concentrations of OM in these layers (Teixeira et al, 2003;Santiago et al, 2008;Martin-Rueda et al, 2007;Vukasinovic et al, 2015).…”

“…Cultivation under no tillage (NT) increases the amount of OM in the surface layer (Thomas, Dalal, & Standley, 2007;Santiago, Quintero, & Delgado, 2008;Aziz, Mahmood, & Islam, 2013;Motschenbacher, Brye, Anders, & Gbur, 2014;Vukasinovic, Todorovic, Dordevic, & Rajkovic, 2015;Moreira, Prochnow, Kiehl, Pauletti, & Martin-Neto, 2016) as well as increases the pH when lime is applied to the surface (Caires, Blum, Barth, Garbuio, Kusman, 2003;Teixeira, Souza, Borém, & Silva, 2003;Caires et al, 2005;Fonseca, Caires, & Barth, 2010). In addition, the soil moisture increases and the temperature decreases compared with conventional tillage because organic residues Acta Scientiarum.…”