A new method for assessing land leveling to produce high quality consolidated paddy fields

The quality of leveling of 0.3-ha consolidated paddy fields in Japan was investigated. The leveling of normal consolidated plots was accurate to within 7 cm from a horizontal plane, with an average standard deviation of about 18 mm for the points measured throughout the plot. The investigated paddy fields had inclinations ranging from horizontal to quite steep; the average inclination was 0.56‰ (1/1,718). The traditional assessment method is based on a horizontal plane. Because it is difficult to use this method to assess the leveling conditions of paddy fields that have an inclined surface, a new assessment method that accurately evaluates the sloped plane of a paddy field is proposed. The new method assesses the leveling conditions within a field by means of a "state index" that considers both the inclination and the surface roughness. Using this state index not only allowed the conditions to be effectively evaluated, but also helped reduce the extra workload needed to level the field to the farmers' requirements after the initial consolidation. Electronic Publication