Growth Performance of Diminutive Halophila ovalis Seagrass Related to Substrate Condition in an Abandoned Mariculture Pond

This study evaluated the feasibility of cultivating Halophila ovalis in an abandoned tidal‐connected mariculture pond and compared its growth performances under two substrate types, that is, raw pond soil and open sea soil. There was no significant difference in leaf number between the two substrate treatments during the first 2 months, while pond soil treatment showed a more rapid increase in the leaf number, with significantly higher values than those in the sea soil treatment from the 70 th day onward. However, carbon and nitrogen contents of seagrass biomass, as well as leaf chlorophyll a and b , were not affected by the substrate type. Soil organic carbon content increased in both treatments after the cultivation. The results suggested that H. ovalis could clonally reproduce in the tidal‐connected mariculture ponds, with a faster growth under the pond soil treatment. This highlights the potential use of these ponds as restoration sites to create seagrass communities and nursery environments to provide source plant materials for seagrass restorations.