COMPARISON OF STABLE ISOTOPE SIGNATURES BETWEEN TROPICAL FRESHWATER AND ESTUARINE FOOD WEB MODEL

摘要

Humans are modifying rivers and estuaries by altering the natural morphology of the water bodies, which may lead to trophic food web imbalances. Ecologists have begun measuring river and coastal ecosystem in an attempt to conserve natural ecological conditions and health. Stable isotope analysis has helped from the last two decades in identifying sources of nutrition supporting fisheries' production. This study provides a food web model of freshwater and estuarine fishes from Perak River, Malaysia tosupport the existing food web in this river catchment. Freshwater food web shows unclear pattern between primary consumer and secondary consumer which may indicate overlapping feeding habit between the primary and secondary consumers in the freshwater.Meanwhile, estuary showed a clear pattern between the bottom and top trophic positions. This factor may be related to their distinct diet in the estuary. Overall, this study provide a detailed understanding of food web within a river basin comprising ofthe freshwater and estuarine region and highlight the importance of food sources in sustaining fish productivity.