Jejaring Makanan pada Biota di Perairan Danau Toba Provinsi Sumatera Utara

Abstract

Lake Toba, as an aquatic ecosystem rich in biodiversity, faces challenges in the balance of its food webs. The food web is a complex system that describes the trophic relationships between organisms in an ecosystem. Some of the main factors include the introduction of invasive species, pollution and human activities. This study aims to determine the form of food composition, food web structure and recommendations for ecosystem management of the food web in Lake Toba. This study was conducted from August-November 2024 with 21 location points. The results of the study showed that detritus is the main food source for the species Channa striata, Mystacoleucus padangensis, Poecilia reticulata and Chromobotia macracanthus, the phytoplankton group is dominated by Oreochromis niloticus and Osteochilus vittatus. Zooplankton is the main food for Osphronemus goramy and Aplocheilus panchax. Oxyeleotris marmorata and Monopterus albus make pisces their main food. While macrophytes, worms and crustaceans are included in the complementary food group. The food web in the biota in Lake Toba shows differences in trophic peaks in the two regions. In the South, Oxyeleotris marmorata and Monopterus albus occupy the trophic peak, while in the North, the position is occupied by Oxyeleotris marmorata and Amphilophus labiatus (red devil fish). Phytoplankton, detritus and macrophytes occupy the lowest trophic level and have the highest biomass among the others.