Experimental Cultivation and Transplantation of Seagrass: A Case Study in Southern of Thailand

Abstract

Seagrass meadows are crucial components of coastal ecosystems, providing essential services such as carbon sequestration, sediment stabilization, and habitat support for marine biodiversity. However, these systems are increasingly threatened by anthropogenic pressures and environmental change, particularly in Southeast Asia. This study aimed to investigate the feasibility of seagrass cultivation and transplantation as a restoration strategy in southern Thailand, focusing on two provinces-Phang Nga and Krabi. A two-phase experimental design was employed. In Phase I, seagrass seedlings were cultivated under ten controlled environmental conditions (C1–C10) that varied in light exposure, substrate type, and biotic interactions. Phase II involved transplantation of the matured seedlings to three natural locations: Bang Khwan Beach, Ko Jum Island, and a shrimp pond in Krabi. Over a 52-week monitoring period, leaf morphology and environmental variables were systematically recorded. Initial post-transplant survival was promising at approximately 80%, yet declined sharply to 20% within four months due to herbivory and monsoonal sedimentation. Surviving plants displayed robust traits, with an average of six leaves per shoot, leaf lengths of 20 cm, and widths of 1 cm. In contrast, plots protected with mesh structures showed significantly enhanced outcomes, with average leaf lengths reaching 35 cm and widths increasing to 1.5 cm. These findings underscore the importance of physical protection in early-stage seagrass restoration. The study concludes that seagrass transplantation is a viable but context-dependent strategy requiring integrative protection against biophysical stressors. It recommends implementing protective enclosures and aligning transplantation schedules with local seasonal patterns to enhance survival and long-term ecological success.