Relationship between the surface sediment substrate characteristic with the abundance of macrozoobenthos in River Ranggeh, West of Sumatra

Abstract

The bottom substrate is one of the main ecological factors that influence the structure of the aquatic organism. Macrozoobenthos are the organisms living either in the bottom waters or the bottom surface of the waters. The presence of macrozoobenthos in the water is strongly influenced by various environmental factors such as temperature, salinity, dissolved oxygen, pH, and substrate of the bottom water. This study aimed to analyze the characteristics of the physico-chemical of waters and the substrate bottom of River Ranggeh, as well as their relationship to macrozoobenthos abundance. Samples were taken in 2019 for five times (February, March, April, July, and August). Survey method was used in this study. Purposive random sampling was carried out at four stations based on the environmental factors and land use. Insect class was the most dominant class found at all study area with the diversity index value of H'> 1 (high diversity). Type of the bottom substrate of River Ranggeh is argillaceous sand with high organic carbon concentration values. The results of the Canonical Correspondence Analysis showed that the abundance of macrozoobenthos was positively correlated with temperature, TSS, P-organic and C-organic, but it was negatively correlated with pH, water flow, DO, Total N, and substrate type.