Community structure of invasive aquatic invertebrates in coral reef ecosystems in the KKPD PISISI Simeulue

This study aimed to determine the structure of invasive aquatic invertebrates through the approach, diversity, similarity, dominance, distribution, and comparison of invasive aquatic invertebrates with coral cover in coral reef ecosystems in PISISI KKPD. This research was conducted in September 2019 using the purposive sampling method to research points, collecting invasive aquatic data used the belt transect method and collecting coral reef data used the Point Intercept Transect (PIT) method. The results of the study found that the structure of invasive aquatic invertebrates in KKPD PISISI was in the good category indicated by the density invasive aquatic invertebrates of 39.67 individuals/m2, the biodiversity index was 1.50 with the medium category, the similarity index is 1.06 in the high category and the dominance index is 0.44 in the low category. The distribution of invasive aquatic invertebrates in the PISISI KKPD includes a cluster distribution. The highest value of invasive invertebrate water was 12.83 ind/m2 and the proportion of coral cover was 29.83% and the lowest was 3.67 ind/m2 and the proportion of coral cover was 54.67% showing the effect of invasive aquatic invertebrates on the proportion of coral cover.