The National Forest Inventory (NFI) is important for providing fundamental data for basic forest planning and the establishment of forest policies for the purpose of implementing sustainable forest management. The purpose of this study is to present the development of Korea's NFI including legal basis, sampling design, and measured variables and to review the usage of NFI data. The survey methods and forestry statistics among the Unites States, Canada, Japan, China, and European countries were briefly compared. Total 140 publications utilizing NFI data between 2008 and 2015 were categorized with 15 subjects. Korea has conducted the NFI 6 times since 1971, but only the 6 th NFI is comparable with the fifth, the previous NFI, because the permanent sampling plots have been shared between the periods. The Korean Forestry Statistics contains only half as many variables as that of advanced countries in Forestry. More researches were needed to improve consistent measurement of diverse variables through implementation of advanced technologies. Additional data for Forest Health Monitoring since the NFI 6 th must be under quality control which will be an essential part of the inventories for providing the chronological change of forest health.

In a forest ecosystem, the major pathway for carbon and nutrient cycling is through litterfall, which has been influenced by physical and biological factors. The purpose of this study was to investigate monthly litterfall production in three forests in Jeju Island differentiated based on precipitation and forest composition: Chungsu (<i>Quercus glauca</i> as the dominant species; low precipitation), Seonheul<sub>b</sub> (<i>Q. glauca</i> as the dominant species; high precipitation), and Seonheul<sub>m</sub> (<i>Q. glauca</i> and <i>Pinus thunbergii</i> as the dominant species; high precipitation). Litterfall was collected monthly from April to December 2015 and divided into leaf litter, twig, bark, seeds, and unidentified materials. The amount of leaf litter by species varied by stand, but leaf litter and total litterfall were very similar among stands, ranging from 362 g m<sup>-2</sup> to 375 g m<sup>-2</sup> for leaf litter and 524 g m<sup>-2</sup> to 580 g m<sup>-2</sup> for total litterfall. However, oak leaf litter was the highest in May, but needle litter was the highest in December. Forest type and climate factor had no influence on the amount of litterfall in the studied forests while the litterfall production by species showed considerable seasonal variation, resulting in varying effects on carbon and nutrient cycling in these forests.