UPV Theses and Dissertations
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Item The effect of different levels of salinity on the spanning of ablated mudcrab Scylla serrataBueno, Jesse L. (Division of Biological Sciences, College of Arts and Sciences, University of the Philippines Visayas, 1994-04)Four salinity treatments with salinity levels of 15 ppt, 25 ppt, 35 ppt and 45 ppt with six replicates per treatment were utilized to determine its effect on the spawning of sexually mature bilaterally ablated mud crab Scylla serrata. The crabs range in weight from 250 grams to 580 grams and carapace width from 12.5 cm. to 16.5 cm. The results of the study showed significant difference (P<0.05) in the number of days when spawning occurred. The shortest duration when spawning occurred was at 25 ppt salinity with a mean value of 9.5 days. This was followed by 35 ppt and 15 ppt salinities with mean values of 15.69 days and 19.83 days respectively. Highest number of days when spawning occurred was at 45 ppt salinity at 24 days. All crabs died 2-3 days after spawning.Item Embryonic development and hatching rate of grouper (Epinephelus suillus) eggs incubated at different stocking densitiesBofill, Aileen B. (Division of Biological Sciences, College of Arts and Sciences, University of the Philippines Visayas, 1992-04)Fertilized eggs of the grouper Epinephelus suillus were obtained from natural spawning of broodstock reared in a 50—t concrete tank at the Aquaculture Department of the Southeast Asian Fisheries Development Center, Tigbauan, Iloilo. The development of eggs incubated at three different stocking densities (50, 1OO, and 150 eggs/1) were monitored. Hatching rates in the different treatments were also determined. Fertilized eggs were floating, non—adhesive, transparent, and spherical in shape with a mean diameter range of 0.83 — 0.84 mm. The yolk was colorless, transparent, and possessed a single oil globule of 0.22 mm in diameter. The eggs have developed into the 2—cell stage 45 min after stocking. Eggs incubated at 1OO eggs/1 hatched 24 h after stocking, while hatching occurred after 27 h and 5 min at 50 eggs/1. No hatching was observed at 150 eggs/1 stocking density even after 28 h post—stocking. Water temperature and salinity during the experiment were 27 ° C and IB ppt, respectively.Item The community structure of mangroves in Barangay Poblacion and Barangay Pinamuk-an, New Washington, AklanBlanco, Florence T. (Division of Biological Sciences, College of Arts and Sciences, University of the Philippines Visaya, 2004-04)Mangrove ecosystems presently cover an area of about 20 million hectares worldwide. Mangroves grow in environmental settings ranging from highly humid to extremely arid conditions, and in soils which range from pure clays to peat, sand or coral rubble. This study was conducted to assess the community structure of mangroves in Barangay Poblacion and Barangay Pinamuk-an, New Washington, Aklan, using the transect line method of English et al (1995). Specifically, it aimed to determine selected physical and chemical factors such as salinity, pH, temperature for water and soil as well as characterization of substrates; to identify and classify true mangrove species present in the area; to describe the community structure in terms of stand basal area, stems per hectare, relative density, relative frequency, relative dominance, importance value, shannon index of diversity, zonation patterns, seedling and sapling density. No study had been conducted to document the community structure of mangroves in New Washington, Aklan. This study was done to provide these vital information needed for its proper management. Five stations were selected in Barangay Poblacion and Barangay Pinamuk-an, New Washington, Aklan. Twenty-two (22) species of mangroves were identified belonging to nine (9) families: Avicenniaceae -Avicennia alab, A marina, a officinalis, A rumphiana; Bombaceae - Camptostemon philippinensis; Combretaceae - Lumnitzera littorea, L racemosa; Euphorbiaceae - Exoecaria agallocha; Meliaceae - Xylocarpus granatum, X moluccensis; Myrsinaceae - Aegiceras corniculatum; Myrtaceae - Osbornia octodonta; Palmae - Nypa fruticans; Rhizophoraceae - Bruguiera cylindrica, B parviflora, Ceriops decandra, Rhizophora apiculata, R mucronata; Rubiaceae-Scyphiphora hydrophyllacea; Sonneratiaceae -Sonneratia alba, S caseolaris; Sterculiaceae-Herittiera littoralis. The study area had a water salinity of 6 ppt to 25 ppt ; water temperature of 27 °C to 30 °C ; soil temperature 27°C to 29°C ; water pH 2.29 to 7.80; soil pH 6.30 and 7.59. Basal area ranged from 0.008 m2/ha for Bruguiera parviflora to 114 nr/ha for Sonneratia alba The species with the highest average stems per hectare recorded was Avicennia rumphiana with 3320. The species with the highest average density recorded was Avicennia rumphiana with a value of 54.984. The station with the highest density was Station 3 and 4 while Station 1 and 5 had the lowest. Two species had the highest Relative Frequency. Xylocarpus granatum and Sonneratia alba were in all stations with 100% occurrence. From the 22 true mangrove species recorded, Avicennia rumphiana had the highest relative dominance of 462.30; the least was Bruguiera parviflora (0.06). The most important species was Avicennia rumphiana (118.51) while the least was Sonneratia caseolaris (1.23). The area is considered to be highly diverse at 0.7835. While on a per plot basis, Station 5 had the highest at 0.9439 while least at Station 1 with 0.5709 Index of Diversity.Item Temporal variation in the subtidal macroinfaunal composition of a NaGISA seagrass bed in southern Guimaras, Philippines between 2015 and 2016Bacabac, Earl Jeroh I. (Division of Biological Sciences, College of Arts and Sciences, University of the Philippines Visayas, 2019-06)Seagrass meadows are amongst the most abundant and diverse ecosystems when it comes to biodiversity but due to stress induced by natural and anthropogenic factors, a worldwide decline threatens the vital ecological functions of these habitats. Studying the infauna provides clues and information about the complexity of seagrass ecosystems and provides information that would facilitate better seagrass area management and associated conservation efforts. The NaGISA sampling protocol was conducted in Calaparan seagrass bed in TINMAR, Guimaras, Philippines between Sept. 2015 and 2016. Overall macrofaunal density was recorded at 21,954.80 ± 36,109.62 ind.m'2 with macrofaunal density higher in 2015 than in 2016 albeit, insignificant except for capitellid polychaetes. Community structure analysis also found similarity in dominance patterns in the subtidal zone with other soft-bottom macrofaunal studies in the Philippines with polychaetes, nematodes, and crustaceans as the respective dominant macrofaunal groups observed. Dominant polychaete families were also found to be cosmopolitan and opportunistic. Granulometric analysis characterized the sediment as pebble to medium sand with mid phi values ranging from -3.69 to 1.10 but poor sorting in all sampling points was observed. Cymodoceaceans dominated the subtidal zone in both years (Halodule pinnifolia in 2015; Cymodocea rotundata in 2016). Correlation analysis showed macrofaunal densities to have a significantly strong negative relationship with sorting index and percent gravel while a strong positive relationship with percent seagrass cover. The poor sediment sorting, coarse sediment character, and seagrass cover were the primary factors influencing the observed decrease in macrofaunal density but the decrease is considered normal for the variability of macrofauna in the area. A clearer picture of macrofaunal interactions would be provided with comparison to intertidal macrofauna of the area in the sampling years and data on additional factors that were not measured in the study.Item Composition of abundance of meiofaunal assemblages found in Banate Bay during NE monsoon and early summerArrivas, Johny Kevin B. (Division of Biological Sciences, College of Arts and Sciences, University of the Philippines Visayas, 2015-05)The study was conducted in Banate Bay, Philippines to describe the composition and abundance of the meiofaunal assemblage in the area. Field sampling was done during December 2012 and March 2013. A total of 41 taxa were identified, dominated by nematodes followed by harpacticoid copepods. The overall mean density of meiofauna in the shallow waters of Banate bay was 28.8 ind.cm'2. The high meiofaunal density recorded in the present study was due to sediment granulometry, water depth and percent organic matter. Macrofauna: meiofauna ratio was also high due to sparse number of macrofauna observed and the physical disturbances associated with seasonal rainfall. The highest density was recorded in March 2013 and the lowest was recorded in December 2012, albeit no significant difference. The temporal distribution of meiofauna was positively correlated with salinity (R = 0.59). Seasonal rainfall also influenced the meiofaunal abundance by affecting turbidity and salinity as well as causing physical disturbances (e.g., storm). Spatial distribution of meiofauna between the stations was influenced by salinity rather than the sediment granulometry, organic matter and turbidity.Item Effect of salinity on the embryonic development of Portunus pelagicus and Charybdis feriatus eggsAlba, Kristine Margaret A. (Division of Biological Sciences, College of Arts and Sciences, University of the Philippines Visayas, 2003-03)The effect of salinity on the embryonic development of Portunus pelagicus and Charybdis feriatus was studied. The five different salinity levels used were 15 ppt, 25 ppt, 35 ppt, 45 ppt, and control (33-35 ppt) to compare their effect on the embryonic development of both species. One thousand newly spawned crab eggs were incubated in vitro in 4-L Nalgene fiberglass containers with 3-L of water at different salinity levels. Mild aeration that allows movement of eggs within the water column was provided. There were three replicates per treatment. Embryonic development of eggs (30 eggs were taken in every salinity level) was monitored daily up to hatching. The newly hatched larvae were then collected and counted. Results showed that during the incubation period, the most advanced stage of embryonic development for Portunus pelagicus was at 33-35 ppt and for Charybdis feriatus was at 35 ppt. There was normal embryonic development and hatching at 35 ppt, 45 ppt, and control (33-35 ppt) for Portunus pelagicus and at 15 ppt, 25 ppt, 35 ppt, 45 ppt, and control (33-35 ppt) for Charybdis feriatus. Eggs that were incubated at 15 ppt and 25 ppt for Portunus pelagicus died. There was normal embryonic development in both species when incubated at 45 ppt. Hatching rate for Portunus pelagicus at control (33-35 ppt) was 34.1 %, at 35 ppt was 16.1 %, and at 45 ppt was 5.8 %. Hatching rate for Charybdis feriatus at 35 ppt was 52.5 %, at control (33-35 ppt) was 21.2 %, at 45 ppt was 12.8 %, at 25 ppt was 6.7 %, and at 15 ppt was 0.3 %. To summarize, embryo of Charybdis feriatus eggs can withstand a wider range of salinity: from a low salinity of 15 ppt to a high salinity of 45 ppt, that makes them a euryhaline species. On the other hand, Portunus pelagicus cannot support embryonic development at lower salinities of 15 and 25 ppt that makes them a stenohaline species.Item Salinity tolerance of the angelwing clam, Pholas orientalis larvaeAguaras, Lovie Grace P. (Division of Biological Sciences, College of Arts and Sciences, University of the Philippines Visayas, 2011-03)Pholas orientalis, locally known as “diwal” is one of the commercially important bivalves in the Philippines due to its delicate and sweet taste. An experiment was conducted to determine the salinity tolerance of the 24-hour-old larvae of this clam when reared in different salinity levels of 25, 30, 35, and 40 ppt. The experiment lasted for 15 days at a rearing temperature of 25° C - 27° C. Determination of survival rates and water change were done twice every week. The data gathered were then analyzed using one-way ANOVA. Results showed that survival rates were significantly high at salinities of 30-35 ppt and were significantly low at salinity levels of 25 and 40 ppt. It was also observed that there was an increasing trend of mortality with prolonged exposure to different salinity levels. This could be attributed to the limited osmoregulatory capabilities of the larvae. When reared at low salinity levels, larvae were faced with the danger of too much water entry which eventually led to death. Meanwhile, when reared at high salinity levels, the larvae died due to outward movement of water which resulted to dehydration. Information on the salinity levels that could be tolerated by diwal larvae will be an important factor in the development of larval rearing techniques for successful hatchery operations. The juveniles or seeds produced in the hatchery could be used to restock the depleted resources in the wild.Item Phytoplankton assemblages in contrasting seasons in the area of Banate Bay, Iloilo, PhilippinesAlvarez, Rose Ann T. (Division of Biological Sciences, College of Arts and Sciences, University of the Philippines Visayas, 2019-06)Banate Bay in Iloilo is one of the major food and occupation contributors in the Panay Island because of its rich biodiversity. This study investigated the phytoplankton assemblage and their diversity with respect to the contrasting seasons namely; December 2012 and June 2013 on the pre-selected nine (9) stations of the Coastal Ecosystem Conservation and Adaptive Management (CECAM) Project. Physicochemical parameters such as salinity, turbidity, DO, and pH did not display seasonality but total suspended solids (TSS) did, with increased values resulting from run-off from the surrounding watershed and rivers. Principal Component Analysis divided the stations during the two months into groups. Station B3 during June 2013 possessed low salinity level, low turbidity level, low pH level and a very high DO level. While the other stations during June 2013 and all the stations during December 2012 possessed higher salinity levels, higher turbidity levels, higher pH levels and lower DO levels. While the PC2 of PCA divided the stations according to the TSS levels and the temperature. All stations during December 2012 showed characteristics of higher TSS levels and lower temperatures while stations during June 2013 were observed to have low TSS levels and higher temperatures. A total of 86 genera falling under six families were identified from the samples, namely: bacillariophyceae (49 genera), dinophyceae (24 genera), cyanophyceae (6 genera), silicoflagellate (4 genera), chlorophyceae (1 genus), euglenophyceae (1 genus) and Miscellaneous (2 genera). In December 2012, a total of 84 genera were identified and 86 genera in June 2013. The top 10 genera with the highest mean densities were Bacteriastrum, Chaetoceros, Eutintinnus, Guinardia, Leptocylindricus, Lioloma, Protoperidinium, Thallasiothrix and Trichodesmium. Pearson’s correlation analysis revealed that water temperature and TSS were the most significant parameters influencing the distribution and seasonal shift in phytoplankton families and genera such as Bacillariophyceae, Others (composed of Euglenophyceae, Chlorophyceae, Myrionecta, and Globigerina), Protoperidinium, and Guinardia. pH and DO had minor influence on phytoplankton distribution. Shannon- Wiener diversity index as a pollution index suggested that the study area was incipiently polluted at stations Bl, B2, and B3 and marginally polluted at Stations B4, B5, GN1, GN2, GS1, and GS2. Despite potential effects of various human activities, the water quality and phytoplankton assemblage of this area has not reached an alarming situation. The current study provides valuable baseline data.Item Effect of salinity on survival and growth of Scylla olivacea crabletsAndres, Eileen Beth N. (Division of Biological Sciences, College of Arts ad Sciences, University of the Philippines Visayas, 2002-04)The effect of salinity on survival and growth of Scylla olivacea crablets was investigated. Salinities of 12, 16, 20, 24 and 32 ppt were used as treatments. Survival, molt interval and growth in terms of weight, carapace length and carapace width were measured for two molts. Growth was measured three days after every molt. There was no significant difference on survival of the crablets between salinities at molt 1. At molt 2, survival was significantly higher at 32 ppt compared to survival at 12 ppt but not significantly different from survival at 24, 20 and 16 ppt. Moreover, duration of survival was significantly higher at 32 ppt than at 16 and 12 ppt but not significantly different from durations of survival at 24 and 20 ppt. On the other hand, molt interval was not significantly different at salinities of 12, 16, 20, 24 and 32 ppt from C1 to C2 and from C2 to C3. Although the highest weight, carapace length and carapace width were observed at 20 ppt at molt 1, there was no significant difference in growth of the crablets at different salinities. At molt 2, the highest weight was at 32 ppt, the highest carapace length was at 24 ppt and the highest carapace width was at 16 ppt and 32 ppt. No significant difference was found in growth of the crablets between salinities at molt 2.Item Effects of pH and salinity on growth and survival of juvenile sea cucumber Holothuria scabra (Jaeger, 1833)Abagat, Christian M. (Division of Biological Sciences, College of Arts and Sciences, University of the Philippines Visayas, 2012-03)Sea cucumber aquaculture could provide a solution to both enhance declining wild sea cucumber populations through restocking and provide sufficient beche-de-mer product to satisfy the increasing Asian market demand. The growth and survival of hatchery-reared Holothuria scabra juveniles at different pH-salinity levels were investigated. Juveniles were exposed for 14 days in six pH-salinity levels: Trt 1 (pH 6.5 — 6.7, 26-28 %o), Trt 2 (pH 6.5 - 6.7, normal salinity), Trt 3 (pH 7.0 - 7.2, 26-28 %o), Trt 4 (pH 7.0 — 7.2, normal salinity), Trt 5 (normal pH, 26-28 %o) and Trt 6 (normal pH, normal salinity) as the control. Multivariate analysis of variance (MANOVA) with repeated measurements revealed that pH and salinity had a significant effect on growth (length, width, and weight) and survival of H. scabra juveniles. Slight seawater desalination combined with high acidification (pH: 6.5-6.7) had lethal effects on H. scabra juveniles. While H. scabra juveniles could be reared in seawater with pH ≥ 7.0- 7.2 and salinity ≥ 26-28 %o, ambient seawater conditions remained the most suitable in rearing H. scabra juveniles for optimum growth and survival.