THE HANDLING OF SUGARCANE TRASH II. EFFECTS OF VARIOUS PRACTICES ON SOIL PROPERTIES

Abstract

Data are presented here for various soil characteristics on plots where the sugarcane trash had been either burned, buried, or aligned in alternate rows for 6 consecutive years in a plant and 6-ratoon crop cycle. The experiment was established in a Vega Alta silty clay, a rather extensive sugarcane soil of the humid area. After the sixth ratoon crop was harvested, infiltration tests were run in the field and bulk and core samples taken for laboratory analysis. No significant differences were observed between the mean pH and total nitrogen values of soil under the various treatments. The mean organic-matter content of soil from plots where the trash was burned was significantly lower, at the 1-percent level, than that of soil from plots where it was buried or aligned. The C/N ratio was narrow in all cases, but lower under the burned-trash treatment. The mean infiltration rates at the eighth-hour run were 1.40, 2.00, and 2.38 inches per hour for soils that underwent the burned-, aligned-, and buried-trash treatments, respectively, but the differences were not significant. No significant differences were observed between the means of the various physical measurements performed, namely, permeability, quick drainage, maximum saturation, water removed and retained at pF 1.78, bulk density, total porosity, and air porosity. Some trends observed may become significant with continuous accumulation of organic matter in soils undergoing the buried- and aligned-trash treatments. For instance, the permeability of soils from plots where the trash was burned tended to be lowest, and the upper layer of soil from plots where the trash was aligned seemed to retain more water at low tensions than the upper layer of soil from plots treated otherwise.