SciELO - Scientific Electronic Library Online

 
vol.16 issue6Simulation of nitrogen management in upland rice with ORYZA/APSIM 2000 modelComparative analysis of models for design of infiltration basins in unpaved roads author indexsubject indexarticles search
Home Pagealphabetic serial listing  

Revista Brasileira de Engenharia Agrícola e Ambiental

On-line version ISSN 1807-1929

Abstract

ANDRADE NETO, Torquato M. de et al. Potassium estimation in the soil solution based on electrical conductivity and soil water content. Rev. bras. eng. agríc. ambient. [online]. 2012, vol.16, n.6, pp. 618-623. ISSN 1807-1929.  http://dx.doi.org/10.1590/S1415-43662012000600005.

The objective of this work was to evaluate and to validate models for estimating potassium in the soil solution as a function of bulk electrical conductivity (ECw), soil water content (q) and a soil solution electrical conductivity (ECss). Treatments consisted of using three concentrations of injecting solution of potassium chloride (1.0, 2.5 and 4.0 g L-1) which were applied by two trickle irrigation systems (microsprinkler and drip) during the first cycle of the banana crop cv. Terra Maranhão. Results showed that it is feasible to estimate potassium concentration in the soil solution from data of ECss and q obtained by time domain reflectometry (TDR) using an equation that combined a linear and a potential model. The estimated values of potassium concentration were close to the ones measured along the crop cycle under field conditions, with a mean normalized deviation of 10.0%, maximum and minimum deviation of 5.0 and 13.0%, respectively.

Keywords : TDR; trickle irrigation; fertirrigation.

        · abstract in Portuguese     · text in English     · pdf in English