ANALYSIS OF OCEANOGRAPHIC PARAMETERS ON THE ABUNDANCE OF FISH LARVAE IN EASTERN INDONESIAN WATERS IN THE TRANSITIONAL SEASON II

• Main Author: Hany Restiangsih, Yoke
• Format: Theses
• Language: Indonesia
• Subjects: Ilmu kebumian
• Online Access: https://digilib.itb.ac.id/gdl/view/71296
• Institution: Institut Teknologi Bandung

Eastern Indonesian waters has an important role in Indonesian fisheries, high productivity of fishery product and biodiversity are supported by water productivity. Intensive of capture fishery activities can be dangerous for suistainable fisheries. Fish population are influenced by the success of new individuals to survive or the success of recruitment. The Banda Sea and Makasar Strait are location of fish spawning grounds and the Celebes Sea is the main inflow gate of the Indonesia Throughflow, which transfers water masses from the Pacific Ocean. The high fishing activities must be balanced with sustainable fisheries, one of which is considering the abundance and distribution of fish larvae. This research describes the influence of oceanographic parameters on the fish larvae abundance. The data in this research from the cruise (marine survey) using Bawal Putih III in the transitional season II in the waters of the Celebes Sea (November – December 2019), the Makasar Strait (September 2018), and the Banda Sea (October and December 2018). The oceanographic parameter are sea surface temperature (ºC), chlorophyll-a (mg/m3), photosynthetically available radiation (PAR) (?mol/s m2), salinity (PSU), turbidity (NTU), dissolved oxygen (mg/l), and the abundance of fish larvae (Ind/1000 m3). This research also used secondary data, there are sea surface temperature, chlorophyll-a, PAR (Aqua-MODIS satellite imagery period 2015-2019), salinity and surface currents (Marine Copernicus period 2015-2019). Oceanographic data processing, analysis, and visualization by ArcMap 10.4.1 and MATLAB software, calculate of fish larvae abundance by Microsoft Excel, and to determine the relationship oceanographic parameters and fish larvae abundance using statistical methods principal component analysis (PCA) in XLSTAT. The results of the study based on average monthly climatology data for 2015-2019 show SST in the Celebes Sea of 29.15 – 30.61 oC, the Makasar Strait ranges 29.40 – 30.75 oC and Banda Sea of 27.60 – 31.01 oC. The maximum SST in the Celebes Sea and Makasar Strait occurs in the the transitional season I, Banda Sea occurs in the west monsoon. The minimum SST in the Celebes Sea occurs in the west monsoon, Makasar Strait and Banda Sea occurs in the east monsoon. The concentration of chlorophyll-a in the Celebes Sea tends to be the same every month, the value of 0.20 – 0.26 mg/m3 in the Makasar Strait range from 0.39 – 0.61 mg/m3 with maximum concentration of chlorophyll-a occurring in the west monsoon and the minimum in the transitional season I. Concentration of chlorophyll-a in the Banda Sea of 0.14 – 0.39 mg/m3 with the maximum concentration occurring in the east monsoon and the minimum in the west monsoon. The monthly variability of PAR in the Celebes Sea range from 40.96 – 50.19 ein/m2day with the highest value in the transitional season I and the lowest in the west monsoon, the Makasar Strait and Banda Sea value of 40.76 – 50.55 ein/m2day and 37.18 – 53.54 ein/m2day which have the same trend, the highest in the transitional season II and the lowest in the east monsoon. The monthly salinity value of the Celebes Sea tend to be stable every month of 33.67 – 33.96 PSU, salinity values in the Makasar Strait and Banda Sea of 32.11 – 33.82 PSU and 32.99 – 34.05 PSU, where in the transitional season II the salinity values of the Celebes Sea. Makasar Strait and Banda Sea have the same range of 33.5 – 34 PSU. Oceanographic parameters in the transitional season II in the eastern Indonesia waters werw obatained insitu data from 2018-2019. The values for each waters were the Celebes Sea with SST of 28.95 – 30.65 °C, chlorophyll-a of 0.02 – 0.58 mg/m3, PAR 0 – 41.90 of ?mol/s m2, salinity of 33.07 – 34.25 PSU, turbidity of 0.04 – 1 NTU, and dissolved oxygen of 4.29 – 6.28 mg/l. In the Makasar Strait SST in the range 28.21 – 29.74 °C, chlorophyll-a of 0.01 – 0.91 mg/m3, PAR 0 – 98.45 of ?mol/s m2, Salinity of 33.26 – 34.26 PSU, Turbidity of 0.05 – 2.35 NTU, and dissolved oxygen 4.94 – 6.29 mg/l. Laut Banda SST value range of 28.12 – 30.61 °C, chlorophyll-a of 0.07 – 0.75 mg/m3, PAR 0 – 123 of ?mol/s m2, salinity of 33.38 – 34.7 PSU, turbidity of 0.03 – 0.14 NTU, and dissolved oxygen of 4.13 – 6.02 mg/l. The results of this study indicate that the fish larvae abundance at the night was highest than daytime measurements. The average abundance of fish larvae was in the Celebes Sea in daytime is 1.382 Ind/1000 m3 and at night 948 Ind/1000 m3 with dominant of fish larvae of the Labridae family, the Makasar Strait in daytime is 866 Ind/1000 m3 and at night 3,260 Ind/1000 m3 with dominant Nemipteridae family, and the Banda Sea in daytime is 698 Ind/1000 m3 and at night 1,396 Ind/1000 m3 with dominant Sillaginidae family. The results of the PCA analysis, the fish larvae abundance in the daytime is characterized by high chlorophyll-a, high dissolved oxygen, and low sea surface temperature. The fish larvae abundance in the nighttime is characterized by high chlorophyll-a, high turbidity and low salinity.