Plant species richness (PSR) along island biogeographical gradients in inhabited islands of Shinan-gun, Republic of Korea

The objective of this study is assess the influences of 8 environmental factors, population, coastline length, island area, vegetated area, highest peak, distance to the mainland, longitude, latitude on vascular plant species richness (PSR) of 10 inhabited islands of Shinan-gun, South Korea. In simple regression, the relationships between PSR and distance to the mainland, longitude and latitude were significant at the 5% level. When distance increases, longitude and latitude decrease, plant species richness increases. The relationship between PSR and coastline length, island area and highest peak were not significant at 5% level. But coastline length, island area and vegetated area showed negative relation with plant species richness and highest peak showed positive relation. Relationship between population and PSR was not statistically significant and showed negative relation. This may indicate PSR decrease by the effects of human dynamics, but further research is needed. In stepwise regression method three variables, distance, longitude and latitude, explained 98.0% of the variation in PSR.