Available Zinc levels in soils of Argentina

SAINZ ROZAS, H; PURICELLI, M; EYHERABIDE, M; BARBIERI, P.A; ECHEVERRÍA, H.E; REUSSI CALVO, N.I; MARTÍNEZ, J.P

International Journal of Agronomy and Agriculture Research

International Network for Natural Sciences (INNSPUB)

Lugar: Dhaka; Año: 2015 vol. 7 p. 59 - 71

2223-7054

Adequate grain zinc (Zn) concentration is important because of itsinfluence on human health. TheArgentina Pampas region (APR) provides between 86% and90% of total grain exports by the country. Soils of the Argentina Pampas region had high fertility underpristine condition but intensification of agriculture, increasing grain yields,and poor or no Zn fertilization could reduce soil available Zn. The objectives of this work were todetermine the distribution of available Zn in agricultural and pristine soilsof the Argentina Pampas region and its relationship with some chemicalcharacteristics. Soil samples (0-20 cm depth) were collected and georeferenced(approximately 550 for each condition), and soil organic matter, pH,extractable phosphorus, cation exchange capacity, and available Zn byextraction with diethylenetriaminepentaacetic acid (DTPA-Zn) were measured. Forgeostatistical analysis, indicatorkriging (non-parametric method) was utilized as interpolation method.Agriculture decreased soil organic matter, pH, extractable phosphorus and DTPA-Zn(26.9, 4.6, 57.8 and 69.5%, respectively). Relative decrease of DTPA-Zn wasonly significantly associated with the relative decrease of soil organic matter,although this association was low (r=0.41). Regionally, the DTPA-Zndistribution was very heterogeneous and soil organic matter, pH, extractablephosphorus and cation exchange capacity did not adequately predicted soil DTPA-Znconcentrations (r2=0.16 to 0.26). Agricultural soils of northern,northwestern and southwestern APR (approximately 12,150,000 ha) showed DTPA-Znvalues below 1 mg kg-1, and therefore would present some degree ofZn deficiency for sensitive crops.