Status of planktonic copepod diversity in the Merambong seagrass meadow, Johor, Peninsular Malaysia

The diversity and abundance of planktonic copepods were analysed from zooplankton samples collected within six times throughout the year in the Merambong seagrass area. A total of 48 species from 20 genera and 15 families comprising an average of 78.8%, of the total zooplankton populations were recorded throughout the sampling period. Among the copepod groups, calanoids were the most abundant inhabiting all the stations, taking an average of 51.2% of the total copepod populations. The most common species observed in the area were Paracalanus parvus, Paracalanus elegans, Oithona rigida, and Euterpina acutifrons. The highest copepod density was recorded at 17.0±2.8 x104 individuals/m3. Copepod species diversity (H’) and species richness (d) were highest at H’ = 3.58 and d=7.08, respectively. Species evenness (J) was, however, relatively constant (0.9) during the entire sampling period. The findings from this study provide important baseline information for future research and monitoring programs

Growth of Freshwater Microalga, Botryococcus sp. in Heavy Metal Contaminated Industrial Wastewater

The aim of this study was to determine the growth and the bioremoval capacity of the green microalga, Botryococcus sp. grown in industrial wastewater contaminated with heavy metals. The freshwater green microalga, Botryococcus sp. was cultured in different concentrations of wastewater (25%, 50% and 100%) with an initial cell concentration of 1000 cells/ml for a period of 12 days. Bold basal medium and sterile distilled water were used as positive and negative control, respectively. The Botryococcus sp. grown in Bold’s basal medium showed the highest (P<0.05) average growth rate (7.8 × 106 cells/ml) after a period of 12 days, whereas, the lowest (P<0.05) growth was observed in 50% concentration of wastewater (4.8 × 104 cells/ml). Similar results were obtained for the specific growth rate (µ/day) with an average of 1.93µ/day and 1.22µ/day for the positive control and the 50% concentration respectively. Highest reduction of heavy metals was achieved for chromium which is equivalent to 94%, followed by copper (45%), arsenic (9%) and cadmium (2%). The results of this study suggest the potential of Botryococcus sp. as bioremediator of wastewater contaminated with heavy metals.&nbsp

Preliminary Studies on the fluctuation of the biomass of sizefractionated zooplankton in sea grass bed of Pulau Tinggi, Malaysia

Zooplanktons biomass was extensively studied in the sea grass bed of Pulau Tinggi, Malaysia for six months. In 2015, sampling months were April, June, October, whereas in 2016, April, June, August were the sampling months. A cone shaped plankton net was used with 0.30 m mouth, 1.00 m length and 100 μm mesh size. The fractionation of zooplankton size was carried out in to >2000 μm (large), 501-2000 μm (medium) and <500 μm (small). Zooplankton was classified as copepods, larvaceans, chaetognaths, cnidarians, ctenophores, decapods and polychaetes. Copepods were categorized as Calanoida, Poecilostomatoida, Cyclopoida and Harpacticoida but identified as a total of 54 species, 26 genera and 19 families. We conclude that among the biomass of 3 size fractions; medium (36%) was dominant followed by large and small (32% each) throughout the study period

A tropical harpacticoid copepod, Nitocra affinis californica lang as an effective live feed for black tiger shrimp larvae Penaeus monodon fabricius

Survival and specific growth rates of Penaeus monodon larvae (post-larval stages 1-15), fed with different live feeds and artificial diets, were evaluated using three different treatments, namely: i) Nitocra affinis, ii) combination of Artemia nauplii + N. affinis and iii) artificial diet. The experiment was carried out in 10-L aquaria with 30% daily water exchange for a period of 16 days. The survival rate (61%) and specific growth rate (16.7 %day-1) were highest (p<0.05) in the treatment with shrimp larvae fed with N. affinis. Likewise, the protein contents of N. affinis was found to be the highest (p<0.05) among all the diets used. The fatty acids of N. affinis was dominated by polyunsaturated fatty acids (PUFA) (22:6n3) forming 19.5% of the total PUFA identified. In fact, N. affinis contained the highest (p<0.05) amount of PUFA and the highest (p<0.05) n-3/n-6 ratio amongst the three diets. Analysis of the copepod fed shrimp showed significantly higher (p<0.05) amount of long chain PUFA, both of the n-3 and n-6 series fatty acids, when compared to the artificial diet fed larvae. The results of this study showed that N. affinis has the potential to be used as an effective live feed for P. monodon due to their high PUFA contents and broad size range (nauplii to adults) to cater for different shrimp post-larval stages

Effect of Mixing on the Density and Chlorophyll A Content on Botryococcus Sp.

Optimization of the growth of microalgae is essential due to demand for high biomass yields. In addition, the methods to estimate the growth (as cell density or biomass) of microalgae are tedious. The normal methods include cell counts, optical density, chlorophyll a and ash free dry weight. However, at least two of these methods were done together for every growth experiment to get a better result. Therefore, this study investigates the effect of mixing as one of the many factors that determines the growth of microalgae, Botryococcus sp. In addition, three different methods to estimate the growth (in terms of cell density or biomass) will be utilized.  Three different treatments on the effect of mixing were employed (T1 using aeration; T2 manual hand shake two times daily; T3 no aeration and shaking) for these experiments. The experiment was carried out under outdoor conditions with temperature ranging from 25.8°C to 35.5°C, light intensity from from 200 Lux to 18000 Lux and pH of 7 to 8 units for 24 days using Bold basal medium (BBM) as growth media. Microalgae biomass was estimated by optical density, chlorophyll a and cell count using haemocytometer. The highest density of Botryococcus sp. was achieved (10.74 x 106 cell ml-1day-1; OD of 3.246 at 680nm; 0.7843 mg L-1day-1 chlorophyll a) with aeration. Whereas, the lowest (2.78 x 106 cell ml-1day-1; od 1.007 (680nm); chlorophyll a 0.1586 mg L-1day-1) and (3.07 x 106 cell ml-1day-1; od 0.999 (680nm); chlorophyll a 0.1545 mg L-1day-1)  with shaking and no aeration, respectively. There exist a positive linear relationship between cell counting and optical density (R2=0.96); cell count and chlorophyll a (R2=0.95); and optical density and chlorophyll a (R2= 0.98) were observed. The result of this study suggested that constant aeration is required by the microalgae, Botryococcus sp. for growth in terms of cell density and biomass

Nutrients Variation in Reclaimed Island of Southern Peninsular Malaysia

All living organisms required the nutrients phosphorus and nitrogen for their metabolism, growth and reproduction including seagrass ecosystem. Seagrass required dissolved inorganic nitrogen (N) and phosphorus (P) to maintain growth, where ammonium is considered as the main source of nitrogen, while the main phosphorus sources is phosphate. However, the nutrient cycling process was disturbed by anthropogenic activities. Reclaimed island near to seagrass bed affected the sedimentation and indirectly impacted the nutrient cycling. The purpose of this study is to investigate the nutrient variation in seawater from seagrass meadow. The study was conducted at Merambong seagrass meadow located between the Causeway second link and the Pulau Merambong, Southwest of Johor. Samples were well collected bimonthly from August 2016 until June 2017 and from 10 sampling points. The nutrients studied were including total ammonium nitrogen (TAN), nitrate nitrogen, nitrite nitrogen and soluble reactive phosphorus (SRP). All the nutrients results were compared with Malaysia Marine Water Quality Criteria and Standard (IMWQS). The lowest concentration (2.3 ppb) of nitrite was observed in South area in June 2017 whereas the highest concentration (40.8 ppb). The highest concentration was 32.5 ppb (North) in April 2017 and the lowest concentration was 4.7 ppb in August 2016. In April 2017, low ammonium concentration was 3.5 ppb in North. The highest concentration (57.8 ppb) was detected in North area in October 2016. The highest concentration was detected in North area with 321.8 ppb whereas exceeded the limit (75 ppb) and the lowest concentration was 16.1 ppb in August 2016 of South area. In general, the results of this study show the nutrients concentration in all sampling duration are below the limit lined by IMWQS except for phosphorus concentration detected in June 2017

Culture of microalgae using interstitial water extracted from shrimp pond bottom sediments

Interstitial water, extracted from the bottom sediment of a shrimp culture pond, was rich in nutrients containing total phosphorus with concentration of 25.98 mg/l and total nitrogen of 65.45 mg/l. A diatom, Chaetoceros calcitrans, a green alga, Nannochloropsis oculata, and a cyanobacterium, Oscillatoria sp., were cultured in pure interstitial water (PIW), diluted interstitial water (DIW) and in Conway medium (CM). C. calcitrans showed a significantly higher (P 0.05) in the growth rate of Oscillatoria sp. cultured in interstitial water and that with added silica or a combination of nitrogen, phosphorus and silica. This study indicates that interstitial water extracted from aquaculture ponds, in sterilized diluted form, has the potential to be used as an effective medium for the culture of microalgae. © 2001 Elsevier Science B.V. All rights reserved

Probability models for the distribution of copepods in different coastal ecosystems along the straits of Malacca.

Copepods are the most abundant microcrustaceans in the marine waters and are the major food resource for many commercial fish species. In addition, changes in the distribution and population composition of copepods may also serve as an indicator of global climate changes. Therefore, it is important to model the copepod distribution in different ecosystems. Copepod samples were collected from three different ecosystems (seagrass area, cage aquaculture area and coastal waters off shrimp aquaculture farm) along the coastal waters of the Malacca Straits over a one year period. In this study the major statistical analysis consisted of fitting different probability models. This paper highlights the fitting of probability distributions and discusses the adequateness of the fitted models. The usefulness of these fitted models would enable one to make probability statements about the distribution of copepods in three different ecosystems

Thermogravimetric study and evolved gas analysis of new microalga using TGA-GC-MS

The growing concerns over the environmental challenges emanating from the use of fossil fuels continue to generate interest in finding competitive and sustainable alternatives. This study presents physicochemical characteristics, thermal decomposition profile and kinetics of a new Botryococcus sp. of microalga isolated from Endau-Rompin, Malaysia. The proximate and ultimate analyses were carried out using standard analytical techniques. Thermogravimetric study was conducted in nitrogen atmosphere using a thermogravimetric analyser coupled with gas chromatography-mass spectrometer. The result revealed that the feedstock has high volatile matter (86.74 wt%) and calorific value of 17.18 MJ/kg. The thermal decomposition of the alga sample proceeded via dehydration, decomposition of extractives, hemicellulose, other carbohydrates and lipid evaporation. The kinetics of the alga sample evaluated using a distributed activation energy model showed that the model sufficiently described the pyrolysis of the feedstock with activation energy of 52.72–159.16 kJ/mol. The chemical composition of the evolved gas revealed high content of hydrocarbons, products of carbohydrate and protein decomposition. This suggests that the alga sample is a good candidate for production of valuable precursors for biofuel processing and production of biochemicals