STUDY ON ACROPORA SP. REPRODUCTIVE POTENCY LEAD CORAL REEF REHABILITATION APPLICATION AT KETAWAI ISLAND WATERS, CENTRAL BANGKA

• Main Author: Rizza Muftiadi, M
• Format: Theses
• Language: Indonesia
• Subjects: Ilmu hayati ; Biologi
• Online Access: https://digilib.itb.ac.id/gdl/view/36261
• Institution: Institut Teknologi Bandung

Rehabilitation of coral reef damage done by utilizing the asexual ability. But it failed because disease susceptible, decreased diversity, and lost sexual reproductive potential. It also reflected in Bangka Belitung waters which used for a wide range of utilization. Until now, mechanism of reproductive success in transplantation unknown. While, the recruitment of new populations from spawning process in sexual could be succeed if implantation in habitat known. The purpose of this research to determine the reproductive potential in Ketawai Island waters, Central Bangka Regency, analyzed the environmental factors triggers spawning and estimate of Acropora sp. settled larval growth on artificial substrates. The reproductive and gonad maturity level measured visually and histologically. HCl used to fragments decalcification, histology preparations used paraffin, bouin fixative, dehydrated with graded alcohol and stained with haematoxylin and eosin. Spawning observed directly at 3-4 meters of depth for 5 consecutive nights. Environmental parameters measured in situ such as the moon phases, tides, sea water temperature, currents and salinity. Acropora recruitment observations restricted at artificial substrates made of marble tile size 25x25 cm coated with a mixture of cement and sand then arranged to form a cube. The artificial substrates sank one month prior to spawning and larval settlement Acropora sp. observed at the post larvae settlement stage ninth month after spawning. The results showed the reproduction type of Acropora sp. in Ketawai Island waters was broadcast spawning. Spawning begins in two days prior until one day after full moon between 19:30-20:10 for 7-20 minutes with ± 2.757-11.050 egg-sperm bundles per colony and 160-525?m in diameter. Blue light was the environmental trigger spawning factor that appears in the twilight, the key factors were the warm temperature (29,8-30,7oC), normal salinity (30-31 ‰), quiet stream (0,059-0,071m/s), occurs at the peak of high tide and at night. Recruitment at artificial reefs was 47 with 0-8 colony/substrate. In conclusion, the sexual reproduction success depends on gonadal maturation time, the environmental cue and keys factors and also the availability of substrate.