QUALITY STUDY OF DOMESTIC WASTEWATER IN RIVERS PASSING THROUGH MANADO CITY BASED ON ORGANIC AND INORGANIC MATERIALS

Study on the quality of domestic wastewater in rivers passing through Manado City to Manado bay was done based on organic and inorganic materials. The study aimed to provide suitable information for environmental management of rivers and beaches in the city. Three rivers were selected to be observed, such as S. Bailang, S. Maasing and S. Tondano, using parameter of Biological Oxygen Demand-5 days (BOD5), Phosphate (PO4) and Nitrate (NO3). Water samples were taken from three locations (upper, middle and river mouth parts) in each rivers. The result showed that average concentrations of the parameters, respectively, were 2 mg/L, 0.014 mg/L and 0.388 mg/L in S. Bailang; 17.66 mg/L, 1.858 mg/L and 0.029 mg/L in S. Maasing; and 4 mg/L, 0.289 mg/L and 0.314 mg/L in S. Tondano. In this paper, water quality status of the observed rivers based on current regulation was discussed

POPULATION STRUCTURE OF Acanthaster planci ON THE REEF FLAT AT THE SOUTHERN PART OF BUNAKEN ISLAND

The information on population structure of Acanthaster planci in Bunaken National Park (BNP) is urgent to be presented in order to be considered in decision making especially on coral reef management in BNP. The objectives of  this study was to examine the  population structure of A. planci, represented by the diameter and weight, number of arms, while the density, distribution and types of coral predation by reef animals in the Southern part of Bunaken Island also observed. Data were collected at the three locations namely, front reef flat (FRF), middle reef flat (MRF) and back reef flat (BRF) with total coverage area of ​​100 x 50 meters. Sixty two individuals (41 at night and 21 at day time) were found with a body diameter ranging between 14 – 28 cm, whereas body weight ranged from 80 – 700 gr, with the number of arms between 9 until 17. The density of A. planci during day time was 0.0042 ind/m2, while the night time was 0.0082 ind/m2, moreover the animal is generally spread aggregated. The results of this study indicated that the population of A. planci in BNP was an adult population with density is still relatively normal, despite an alert sign for the sustainability of coral reef ecosystems in the BNP

UJI AKTIVITAS LARVASIDA NYAMUK Aedes aegypti DARI BEBERAPA EKSTRAK ASCIDIAN

Dengue Hemorrhagic Fever (DHF) is a disease caused by virus through Aedesaegypti mosquitoes as the vector. The disease is spreading across the world andendanger and threaten human life. Measures in controlling the vector using the commonlarvaside “abate†are in adequate and less affective. The objectives of the research is tofind out larvaside extracted from three kinds of ascidian. The each ascidians (Polycarpaaurata, Didemnum molle and Rophalaea crassa) were extracted with ethanol, and thecrude extracts were subjected to larvasidal test by dissolving in water containing thelarvae. The remarkable extract activity was partition in ethyl acetate, hexane andbuthanol. The results show that extract of Polycarpa aurata has the highest activity. Theactivity of fractions show that ethyl acetate at 100 ppm reveals the highest mortality oflarvae 100% in 8 hours, followed by hexane fraction (12 hours) then buthanol fraction (18hours). All the fractions (Ethyl acetate, Hexane and Buthanol) could totality kill the larvaewithin 24 hours which is comparable to the abate

PENGARUH BERBAGAI JENIS ALGA MIKRO PADA PERTUMBUHAN LARVA PLUTEUS BULU BABI Echinometra mathaei TIPE A HASIL FERTILISASI BUATAN

Penelitian ini didesain untuk mengevaluasi pengaruh dari pakan alga mikro berbeda terhadap karakteristik pertumbuhan larva pluteus Echinometra mathaei. Sampel E. mathaei diambil dari perairan pantai Tongkaina. Tahap fertilisasi buatan dilakukan dengan mengambil masing-masing 1 ml sel telur dan sel sperma. Larva bulu babi diberi perlakuan 3 jenis alga mikro yakni N. oculata (3 x 106 sel/m), Tetraselmis sp. (l,2 x 106 sel/ml)., dan Prochloron sp. (1 x 106 sel/ ml) selama 70 jam. Pengamatan dilakukan setiap 10 jam dengan mengambil 5 individu dari tiap petri. Hasil uji statistik menggunakan analisis ragam satu arah, mengindikasikan bahwa perlakuan berbagai pakan alga mikro mempengaruhi pertumbuhan panjang lengan anterolateral larva. Perlakuan alga mikro N. oculata memberi pengaruh yang lebih baik terhadap pertumbuhan panjang lengan anterolateral daripada perlakuan alga mikro lain