Effect of Temperature and Nutrient Limitation on the Growth and Lipid Content of Three Selected Microalgae (Dunaliella tertiolecta, Nannochloropsis sp. and Scenedesmus sp.) for Biodiesel Production

Microalgae is one of potential source for biodiesel due to high efficiency of solar energy conversion to chemical energy.\ud Several microalgae also have high lipid content per dry weight of biomass. The aims of the present work to study the effects of\ud temperature and nutrient depletion on the growth and lipid content of three selected microalgae (Dunaliella tertiolecta,\ud Nannochloropsis sp and Scenedesmus sp) in view of their possible utilization as raw materials for biodiesel production. In addition,\ud various lipid analysis methods were applied, such as gravimetric, Nile Red staining and FTIR spectroscopy. Algal growth and lipid\ud content was strongly influenced by the variation of tested parameters; indeed, an increase or decrease temperature from ambient\ud temperature and nutrient depletion practically increase in lipid content. Nile Red staining and FTIR spectroscopy are effective tool to\ud analyze rapidly of lipid content from selected microalgae

Tracking the Response of Phytoplankton following Gyttja Disturbance: a Mesocosm Field Study in Myall Lakes, New South Wales, Australia

This study determined whether artificially mixing gyttja, an organic sediment that contains high levels of NH4, with its overlying\ud waters, affected phytoplankton abundance and species composition in Myall Lake (NSW, Australia). A series of mesocosms was employed,\ud with three mesocosms being designated as controls, i.e. no gyttja mixing, and three others termed impact mesocosms, i.e. in which gyttja was\ud mixed with the overlying waters. Sampling was undertaken during a 5 day period in sediment disturbance, and phytoplankton community\ud variables were recorded at seven intervals, i.e. just prior to disturbance and 30 minutes, 3 hours, 1, 2, 3, 4 and 5 days after gyttja disturbance.\ud Comparisons of these community variables among treatments and over time convincingly demonstrated that overall phytoplankton\ud abundance rose from 20,000 cells/mL just prior to disturbance to between 30,000 cells/mL and 55,000 cells/mL 2 to 4 days after gyttja\ud mixing. This rise in abundance was attributable to a substantial increase in the cyanophycea over the same period. In contrast to the\ud cyanophyceae, the abundance of bacillariophyceae increased sharply following disturbance from 150 to >1000 cell/mL and did not exceed\ud 1000 cell/mL for the duration of the experiment. This supported the hypothesis that gyttja mixing does introduce benthic microalgae into the\ud water column. Sediment disturbance caused differences in species composition in time, with cyanobacteria being mostly influenced taxa.\ud Each period of disturbance between mesocosm have different assemblages of species

Struktur Komunitas Dan Kelimpahan Fitoplankton Di Pulau Kapoposang Kabupaten Pangkajene Dan Kepulauan, Provinsi Sulawesi Selatan (Abundance and Species Assemblage of Phytoplankton at Kapoposang Island, Pangkajene and Kepulangan Regency, South Sulawesi Province)

This research was aim to compare community structure and abundance of phytoplankton in Kapoposang Island. The result of this research was expected to be used as an information of the effect of waters quality on abundances, community structure and phytoplankton species composition in Kapoposang Island. This research was conducted on February and May 2016 in Kapoposang Island, Pangkajene and Islands Regency. Identification of samples was conducted in Fish Pest and Diseases Laboratory, Department of Fisheries, Faculty of Marine Science and Fisheries, Hasanuddin University. The results showed community structure of phytoplankton in Kapoposang Island based on sampling station were not significantly different (P>0,05), whereas community structure of phytoplankton based on rainy and summer seasons were significantly different (p<0,05).Alexandrium kutneraee, Toxarium undulatum dan Bellerochea horologicalesis most contribute species in Kapoposang Island the most average abundancesof phytoplankton was foundon summer season in Kapoposang Island1.591.494 cells/L.Both of the islands has high equitability index value and the distribution was homogeneous. The value of diversity index showed in all of the stations, phytoplankton community were mid stable and the dominance index showed both of the islands have dominant species.Keywords: Kapoposang Island, Phytoplankton, community structure, abundance, ecological inde

INTERACTION OF CO2 AND LIGHT AVAILABILITY ON PHOTOPHYSIOLOGY OF TROPICAL COCCOLITOPHORIDS (EMILIANIA HUXLEYI, GEPHYROCAPSA OCEANICA, AND OCHOSPHAERA SP.)

The study to examine the calcification rate, adaptation, and the biotic response of three tropical coccolithophorids (Emiliania huxleyi, Gephyrocapsa oceanica, and Ochosphaera sp) to changes in CO2 concentration. Three selected calcifying coccolitophorids were grown at batch culture with CO2 system at two levels of CO2 (385 and 1000 ppm) and two light dark periods. The parameters measured and calculation including growth rate, particulate organic carbon content, particulate inorganic carbon content, chlorophyll a, cell size, photosynthetic, organic, inorganic carbon production, photosynthesis, and calcification rate.  The results showed that there was a different response to carbonate chemistry changes and dark and light periods in any of the analyzed parameters.  The growth rate of three selected calcifying microalgae tested was decreasing significantly at high concentrations of CO2 (1000 ppm) treatment on 14:10 hour light: dark periods. However, there was no significant difference between the two CO2 concentrations where they were illuminated by 24 hours light in growth rate.  The increasing CO2 concentration and light-dark periods were species-specific responses to photosynthesis and calcification rate for three selected calcifying microalgae

Pengaruh Derajat Keasaman (pH) Air Laut Terhadap Konsentrasi Kalsium dan Laju Pertumbuhan H A L I M E D A SP

Ocean acidification afected marine organisms especially calcifying organisms, such as Halimeda sp. This study was conducted on June to September 2012 at laboratory of Research Center and Development for Marine, Coastal and Small Islands, Hasanuddin University. The aim of study  to determine the efect of acidic level on Calcium concentration and growth rate of calcifying macroalgae, Halimeda sp. The experiment design was used completely  random  design  with  three  treatments  and  three  replicates.  Analysis  variance  was  used  for  data analysis with advanced respon test. Tukey test was used to compare the diference between treatments. Water quality parameters were analyzed descriptively. The results showed that there was a significant diference of pH treatments on calcium concentration an d growth rate of Halimeda sp. The highest calcium concentration was found  at pH 8. In  conclusion, increasing pH level of media disturbed the calcifying  process of Halimeda  sp especially at pH level of 6, while growth rate of Halimeda sp was not afected wit h the decreasing of pH

Growth response of natural phytoplankton to

The Broadwater of Myall Lakes, NWS Australia is brackish water which has a high variation in water\ud quality in particular salinity and nutrient concentration. In these experiments, we determined the growth\ud and species assemblages of natural phytoplankton community exposed to nutrient enrichment.\ud Laboratory incubation condition was used to measure 10 days biomass and group-specific response of\ud phytoplankton community. Four experimental occasions were conducted in autumn (April and May,\ud 2005) and early summer (November and December, 2005) with two experiments each season. Biomass\ud of phytoplankton was determined based on chlorophyll fluorescence, extracted chlorophyll a and cell\ud abundance of phytoplankton, and community structure/species assemblages was based on manual\ud identification until genus level using upright light microscope. During four experiment events,\ud chlorophyll growth response was significantly higher in N+P treatment than control and N treatment\ud only, with slow growth rate occurring 24 to 48 h following nutrient addition. There was an inconsistent\ud trend of biomass in terms of cell abundance in respond to nutrient enrichment between experiment\ud occasions, except for May experiment. Generally, our study found that the greatest difference of\ud phytoplankton growth/biomass at the Broadwater of Myall Lakes was at site level instead of nutrient\ud treatments. Our study also revealed that urea and other forms of dissolved N stimulated growth of\ud group specific of phytoplankton, with P addition contributed considerably to changing in community\ud structure of phytoplankton. The result of this study suggest that urea was not a factor for\ud Cyanobacteria bloom as compared to the other dissolved N forms, consequently urea does not give a\ud further enhance for Cyanobacteria bloom formation in The Broadwater of Myall Lakes system. This\ud study revealed that enrichment of different forms of dissolved nitrogen stimulated the growth of\ud phytoplankton taxa in ways that resulted in significant differences in species assemblages among\ud treatments for most sites. Extra addition of P can initiate bloom conditions for cyanobacteria. In order\ud to reduce this possibility, P flow from catchment areas has to be prevented

Increasing CO2 Concentration Impact upon Natural Phytoplankton Community at Spermonde Island, Indonesia: Mesocosm Study

Ocean acidification is one of an environment problem due to increasing CO2 concentration. Ocean acidification have\ud shown a negatively impact to marine organisms especially calcifying organisms such as microalgae, coral reef and other invertebrate\ud organisms. Decreasing in carbonate saturation state on the calcification rates of individual species and communities in both\ud planktonic and benthic habitats were occurred due to seawater acidification.\ud The study was conducted at three locations: Barru, Takalar and Barrang Lompo Island using mesocosm technique with two different\ud of incubation periods (48 and 96 hours). Six pCO2 level based on adding acid base treatments were used, which were 280, 380, 550,\ud 650, 750 and 1000 ppm with 4 replicates\ud In general, alkalinity decreased with increasing CO2 concentration. However, length of incubation was showed no significant\ud affected to DIC for all CO2 concentration at Barru and Barrang Lompo mesocosm experiment. PIC and POC showed a varied\ud response between all locations of mesocosms experiment. There was a trend where increasing of POC with increasing of CO2\ud concentration. PIC concentration at Barru and Takalar showed a slightl higher at 96 hours than 48 hours of incubation period and for\ud Barrang Lompo mesocosm experiment PIC was higher at 48 hours than 96 hours of incubation period. Chlorophyll a and cell\ud abundance was decresing with increasing CO2 concentration. Growth, photosynthesis and calcification rate decreased with increasing\ud CO2 concentration