ABUNDANCE OF PHYTOPLANKTON ON THE LARVAE ABALONE (Haliotis.squamata)

Abalone (Haliotis squamata) is one of shellfish to develop for market demand. Phytoplankton play important role as primer producer in larvae rearing. The main purpose of this study was to determine the abundance composition  phytoplankton of  abalone larvae use  Amphora sp concentrate to old different. The research was conducted for one month. The phytoplankton sampling used scissor and brush. Sampling was carried with three day interval. Identification and counting of cells using a microscope with 400X magnification. This research used completely randomized design (CRD) with 3 treatment A ( day 5), B ( day 10) and C ( day 15) with three reflication. The parameter measured were spesies composition of phytoplanton, abundance, diversity, uniformity and dominance. The result showed that spesies composition of phytoplankton consisted  7- 10  in treatment A,  6- 10 ( B) and  6- 9 (treatment C). It was divided into two major group : diatom and non diatom.  Thallasionema sp with the higest of cells abundance  was 33,17 X 10⁴ sel/cm² treatment A , 42,08 X 10⁴ sel/cm² (B) and 34,1 X 10⁴ sel/cm² treatment C. Diploneis sp. the lowest of cells abundance : 1,16 X 10⁴ sel/cm² treatment A, 1,55 X 10⁴ sel/cm² (B) and Navicula sp the lowest of cells abundance: 1,63 X 10⁴ sel/cm² treatment C. Phytoplankton Abundance ranged from, 61-76,58 X 10⁴ sel/cm² (treatment A), 46,33-95,67 X 10⁴ sel/cm² (B) and 47,5-100,3 X 10⁴ sel/cm² treatment C, diversity 1,37 (A), 1,12-1,62(B) and 1,24-1,66 (C), uniformity indeks ranged from  0,69-0,79 (treatment A), 0,51-0,70(B), and 0,61-0,80 treatment (C) and the dominance ranged from 1(treatment A), 0,95-1(B) and 0,48-1 (treatment C) .The growth and Survival rate no significant different. this study suggested that used of Amphora sp concentrate was enable to support grow natural food in each rearing tank of abalone larvae.