No abstract

It is important to form and maintain ridges for air permeability within the upland crop root zone in Saemangeum reclaimed land with poor drainage. The ridge in the area, however, is difficult to be maintained due to high content of sand and silt, which are susceptible to water erosion. This study was conducted to investigate the reduction in the height of the ridge and maize growth as affected by rainfall characteristics through the application of ridge maintenance technology under maize cultivation in Saemangeum reclaimed land. Four treatments were examined: control, ridge covered by residue (RR), vegetation in furrow (VF), and RR + VF. Maize was Kwangpyeongok. The rainfall erosivity factor to compare the rainfall characteristics affecting changes in the height of the ridge was greater at 2,653.5 MJ mm ha -1 hr -1 in the 2nd year than that at 505.8 MJ mm ha -1 hr -1 in the 1st year. No significant difference in the decrease of ridge height (DRH) was found between treatments, but the DRH in 2nd year (8.5 cm) was larger than that in the 1st year (6.6 cm) with the stronger rainfall erosivity. The soil erodibility factor of the tested soil was 0.587 Mg hr MJ -1 mm -1 greater than the national average of 0.027 Mg hr MJ -1 mm -1 . The DRH had a negative relationships with fresh weight of maize implying that reduced ridges provided less functionality for plant growth. Therefore, a variety of conservation treatment is supposed to be studied to maintain ridges for arable lands in Saemangeum.