In the period from June 23 to July 23, 2006, in the regional environment of Araras-SP, it was studied the influence of sugarcane straw coverage harvested mechanically in water content of a dystrophic dark-red Latosol, A moderate and clayey texture. The variation of volumetric water content of soil in these plots was assessed in layers of 0 to 0.20 m and 0.20 to 0.40 m deep. The experimental treatments consisted of covering the soil with quantities of sugarcane straw equivalent to 0 and 1.5 kg.m-2 (0 and 1.5x10(4) kg.ha-1), the first representing the condition without straw and the second condition with straw . The results collected in the 0-0.20 m layer showed that during the study period there was a decrease in soil water content of 0.103% per day provided with straw and 0.223% per day without straw, or more than double the water loss recorded previously. When it was considered the soil layer of 0.20-0.40 m, the decrease in soil water content was much lower than that of the previous situation, the order of 0.116% per day provided with straw and 0.159% per day without straw. An important point to note is that the treatments used in the experiment had a decisive influence on the direction of water movement in the soil.
mulching; sugarcane straw; soil moisture