Soil moisture content and surface temperature in tillage systems and stages of development of maize crop

ABSTRACT The tillage systems affect the amount of crop residue on the soil surface, and hence its temperature and moisture content. To evaluate the variation of moisture content and soil temperature in systems of tillage on maize growth stages, an experiment was conducted in Ultisol. The experiment was conducted with randomized complete block with four replications in Petrolina – PE, Brazil. The treatments consisted of five tillage systems applied to the plots – unprepared primary, off-set disc harrow of 0.56 m, off-set disc harrow of 0.61 m, chisel plow and moldboard plow. The soil moisture and temperature readings were taken at 6, 9, 12, 15 and 18 h for the different maize stages V3, V8, R3 and R6. Soil moisture was measured in the layer between 0.00-0.05 m by means of deformed samples by using gravimetric method and soil temperature at the surface with infrared thermometer. Systems of soil tillage and hours of reading influenced the moisture and soil temperature. The highest values of soil moisture content occur in the morning, while the highest temperature of the soil in the afternoon.

摘要：耕作制度可影响土壤表面作物残体的留存量，进而改变土壤温度与含水率。为评估不同耕作制度下玉米各生育期的土壤含水率与温度变化规律，本研究于巴西佩特罗利纳-PE地区的老成土（Ultisol）地块中开展田间试验。试验采用完全随机区组设计，设置4次重复。处理组包含5种小区耕作制度：初级未整地、0.56m偏置圆盘耙（off-set disc harrow）、0.61m偏置圆盘耙、凿式犁（chisel plow）与铧式犁（moldboard plow）。分别在玉米V3、V8、R3、R6生育期的6、9、12、15、18时采集数据：土壤含水率采用重量法，通过采集0.00~0.05m土层的扰动土样测定；地表土壤温度则通过红外测温仪（infrared thermometer）测定。结果表明，耕作制度与测定时段均对土壤含水率及温度存在显著影响：土壤含水率最高值出现在上午时段，而土壤温度最高值则出现在午后时段。