Studi Komparasi Kelimpahan Fitoplankton dan Laju Produktivitas Primer di Perairan Haranggaol Danau Toba

Abstract

Research on the comparative abundance of phytoplankton and primary productivity rate in the waters of Lake Toba Haranggaol was conducted in December 2014 and March 2015. The purpose of this study was to compare the value of the abundance of phytoplankton and primary productivity rates at several different locations such as cages, dock, tourism and free areas of activity in the waters of the lake Haranggaol. Sampling was conducted using the method of "purposive sampling" in the fourth study sites. Phytoplankton are taken by using a plankton net and identification by using a light microscope. Primary productivity measurements done using Winkler bottles of dark and light. The result is there are 7 classes, 32 families and 47 genera of phytoplankton in the entire station. Phytoplankton with the highest abundance values contained in floating cages station with a value of 15265.31 ind / l, while the lowest was at the station with a value-free activity 10040.83 ind / l. The highest primary productivity values contained in the station floating cages of 258.99 mg C / m3 / day while the lowest at station activity free of 78.83 mg C / m3 / day. Value abundance of phytoplankton very strong influence on the value of primary productivity and value BOD5 very strong influence on the abundance of phytoplankton.