Author(s): Charina Gracia Banaay
Email (s): cbbanaay@up.edu.ph
Institution or organization of origin: University of The Philippines Los Baños
Country: Philippines
Abstract
Corbicula fluminea or Asiatic clams are natives of the freshwater environment in the Philippines, but studies about this organism in the country are limited. Research shows that Asiatic clams are great filter-feeders that can improve water quality. This study aims to determine the biomechanical filtration ability of the clam in terms of age (size) and density. Clam samples were collected from the South Bay of Laguna Lake during the dry (summer) and wet (rainy) seasons of 2019-2020. Clams were grouped based on their age or size, and density (at constant weight). The filtration rate of the clams was measured in a laboratory experiment using the light transmittance of water. To determine whether there are any statistically significant differences between the means of the treatments, two-factor analysis of variance (ANOVA) was conducted. Least significant difference (LSD) was used to make direct comparisons between the treatments.
Results showed that the density significantly contributed to the rate of biomechanical filtration during the dry season when water turbidity was high, while density, age, and their interaction were significant contributors to filtration rate during the wet season when water turbidity was low. In both seasons, the presence of C. fluminea significantly contributed to the changes in the turbidity of the water relative to the control. These results suggest that C. fluminea plays a significant role in the dynamics of aquatic environments. Furthermore, it may be used as natural control for turbidity caused by algal bloom and microbial presence in the water column.