EFFECT OF AGRICULTURAL BURNING IN A VERTISOL OF TABASCO, MÉXICO: CHANGES IN PHOSPHORUS, PH AND ELECTRICAL CONDUCTIVITY

Abstract

Background. The practice of burn in the sugarcane crop is considered necessary to facilitate the harvest, although the possible negative impacts on the soil fertility are questioned. Objective. The aim of the present research was to characterize the burn and its effects on phosphorous, pH and electrical conductivity in a Chromic Vertisol Gleyic cultivated with sugarcane. Methodology. Thus, in one plot, 10 sampling sites were selected, in each one of them, were placed ceramic pieces marked with a coating thermosensitive, these pieces were deposited at 0, 2 and 5 cm depth. At the same sites, soil samples were collected every two cm to a maximum depth of 20 cm, to detect changes in soil variables before and after burning. At the same time, the temperature produced by the burning of the combustible material was measured at three sites of the reedbed, using an infrared thermometer.  Results. The results indicated that, the burning of the fuel material of the sugarcane produces between 372-549 °C of heat, at the soil surface it reaches 473°C, and less than 149 ° C in the layer 0-20 cm deep. Implication.  The impact that this burning causes is a slight decrease in pH and a slight increase in EC in the layer of 0-20 cm depth, as well as a minimal increase in the available P in the first 12 cm of the soil surface. Conclusion. It is concluded that, the wastes burn in the sugarcane crop is of moderate intensity, so that provoke light changes in the edaphic variables EC, pH and available P.