Gastropod Community Structure as Environmental Change Signals for Tropical Status In Sedati Waters, Indonesia

Abstract

Sedati is one of the Sidoarjo Regency's Coastal Areas, which has potential resources in capture fisheries. Many industries in Sedati have caused a decrease in the aquatic productivity and aquatic organism conditions, including gastropods. Gastropods are easy to find in various habitats, but their distribution is highly dependent on the habitat conditions such as physical, chemical and biological factors. Gastropods are sensitive to environmental changes and can withstand the environmental changes that are not too wide to be used as indicators of environmental pollution. This study aims to determine the structure of the gastropod community in the Sedati Waters. The research was performed using an observation method. The gastropod samples were taken using a dredge net, while the substrate samples were collected using Ekman grab. The gastropods found in Sedati Waters from October to December are nine species from 2 orders and six families. The species most commonly found in R. venosa, while the least is C. ventricosa. The abundance index of gastropods every month shows a marked difference between stations but not the other main parameters. The diversity index value was between 1.4846-2.0897. The evenness index value reached between 0.8284 and 0.9548. The dominance index ranged from 0.16 to 0.2299. The community structure of gastropods in the Sedati Waters, Sidoarjo, East Java shows a significant difference (p<0.05) between stations and belongs to the medium category.

Correlation Between Ecological Status of Sedati Waters and Gonadosomatic Index of Short-Necked Clam (<i>Paratapes undulatus</i>)

“…While the pH value, salinity, and the current have a very weak correlation to the gonadosomatic index. These results are in following with research conducted by Hamli et al, (2015); Melati et al, (2021), where salinity, DO, pH, and currents do not correlate with the gonad maturity index of the short-necked clam.…”

Ecological index of freshwater gastropods in Kolaka District, Southeast Sulawesi, Indonesia

“…The ecological index of inland gastropod communities is an indicator of ecosystem stability as indicated by the variability of species diversity, species evenness, and species dominance of a group of sessile organisms capable of recording inputs of organic and inorganic materials that enter their habitat (Octavina et al 2019;Dewiyanti et al 2021;Melati et al 2021;Stanković et al 2021;Purnama et al 2022b;Valentino et al 2022). Kolaka is one of the regions in Southeast Sulawesi Province with a high diversity of inland gastropod resources (Purnama et al 2019a).…”

Evaluation of larval Beautiful Groupers (Epinephelus fuscoguttatus x E. microdon) using Chlorella sp. and Artemia sp.

“…Then, the egg stocking was done slowly, and the eggs would hatch within 18-20 hours. The characteristics of a good and developing egg cell are being transparent or floating [22]. Meanwhile, unfertilized eggs have the characteristics of being white in color and settling at the bottom.…”