To clarify the current status of irrigation pond abandonment and the problem for aquatic plant conservation, we investigated the percentage of abandoned pond in local area, the relationship between the depth of pond and aquatic and meadow plants diversity at farm village on hilly terrain in northern part of Awaji Island. The investigation was carried out by interviewing 133 pond manager and by field survey. We found half of ponds had been abandoned already, and, we verify the strong correlation between depth of pond and species richness of aquatic plants.
