The objective of this study was to assess the effects of gypsum application on dry matter yield (DMY), mineral content of alfalfa (Medicago sativa L.), and soil properties in reclaimed tidal land in South Korea. The experiment was conducted in Seokmun, located on the west coast of South Korea, which is reclaimed with approximately 70 cm depth of degraded island soil. Treatments consisted of a control with no gypsum application (G0), 2 ton ha-1 (G2), and 4 ton ha-1 (G4) of gypsum application. The first harvest was carried out when the alfalfa reached 10% flowering, and subsequent harvests were conducted at 35-day intervals. Over the three-year experimental periods (2019-2021), the total DMY of G2 treatment was significantly higher than those of G0 and G4 (p<0.05). Although both G2 and G4 gypsum application treatments lowered soil pH, the G4 treatment increased the electrical conductivity (EC) content of the soil. Additionally, gypsum application affected the mineral contents of alfalfa, resulting in reduced concentration of sodium (Na) and Magnesium (Mg). Therefore, this present study suggests that a gypsum application rate of 2 ton ha-1 is optimal for improving alfalfa dry matter yield and mineral balance, as well as enhancing soil chemical properties in reclaimed tidal land in South Korea.

This study evaluated the feasibility of integrating the carbon storage of grasslands in Gangwon province into the InVEST carbon storage and sequestration model using large-scale digital land cover maps. Land cover maps from 1980, 1990, 2000, and 2010, obtained from the Environmental Geographic Information Service, were analyzed, with 28 maps examined for each year. Grassland carbon storage in Gangwon province was estimated through the InVEST software. The findings indicated that the grassland area showed an increase in 1990, followed by a declining trend, contrasting with the continuous reduction observed in actual managed grassland areas. Discrepancies between mapped and managed grassland areas were attributed to the classification criteria of the land cover maps, which included non-forage land uses such as golf courses, ski resorts, and green spaces, resulting in overestimations of grassland areas. To enhance accuracy, the adoption of land cover maps with refined grassland classification criteria is necessary. Accurate representation of grassland areas in land cover maps is critical for reliable estimation of grassland carbon storage using the InVEST software.