Growth Pattern of Skipjack Tuna (Katsuwonus Pelamis) Landed in PPI Kedonganan Bali

Skipjack Tuna (Katsuwonus Pelamis) is one of the big pelagic fish in fishery resources that has high economic value and plays an important role in export activity in Indonesia. Catch activities for consumption needs for people could threatened of Skipjack Tuna availability. The growth pattern of Skipjack Tuna is needed to used as references for the appropriate management plan to protect Skipjack Tuna. The research was conducted from February to April 2017 at PPI Kedonganan, Kuta District, Badung, Bali. The fish were collected by simple random sampling method. This study showed that gillnet and handline were used as fishing gears. The length frequency distributions were in the long-range of 315-337 mm means the catch fish is still young. The growth pattern of Skipjack Tuna was negative allometric means length growth was faster than weight growth. The growth parameters of Skipjack Tuna were obtained by the asymptotic length (Linf) of 875.2 mm, growth coefficient (K) of 0.09, and theoretical age (t0) of -0.78. Skipjack Tuna have small body size with condition factors were ranged from 0.8783-1.7269. It can be concluded that these methods can be used to determine the appropriate management efforts.

Kimia Fisik Perairan dan Ektoparasit Ikan Nila dan Patin Di Situ Gintung, Tangerang Selatan, Banten

Poor water quality based on physical and chemical waters is one of the factors that influence the infection and presence of fish ectoparasites. The aim of study was to determine the physical and chemical waters, the types and prevalence of ectoparasites and the correlation of ectoparasites with physical and chemical waters. The study was conducted in Situ Gintung, South Tangerang from March to June 2018 with samples from Floating Net Cages (KJA) and fishing. The results showed that the physical and chemical waters generally within standard quality for fish cultivation. The number and type of fish ectoparasites consist of Trichodina sp., Chilodonella sp., Litonotus sp., Vorticella sp., Dactylogyrus sp. and Capillaria sp. Based on the Canonical Correspondence Analysis (CCA) shows that ectoparasites are affected by physical and chemical waters.

Distribusi Spasial Kerapatan Mangrove Menggunakan Citra Sentinel-2A Di TAHURA Ngurah Rai Bali

The mangrove forest of TAHURA Ngurah Rai is one of the mangrove ecosystems in Bali that suffered damages and density changes due to natural factors and human activities. Remote sensing is one of the technology that can be used to estimate the density of mangrove canopy in TAHURA Ngurah Rai. The purpose of this study was to find the best vegetation index for estimating mangrove canopy density out and map it spatially using Sentinel-2A image. The method of this research is using vegetation index NDVI, EVI and mRE-SR to estimate mangrove canopy density. Field data was collected using Stratified Random and Proportional Sampling method by taking photo of the density of canopy using camera with Fish Eye lens on 34 plot. The results of this study show the satistic test of the linear model of the vegetation index with the mangrove canopy density value on the NDVI index (r = 0.8165, R2 = 0.6667, RMSE = ± 8.1508), EVI (r = 0.8597, R2 = 0.7390, RMSE = ± 7.8117), and mRE-SR (r = 0.9277, R2 = 0.8607, RMSE = ± 4.9571). The conclusion of this research is mRE-SR vegetation index able to map mangrove canopy density better than NDVI and EVI vegetation index with 86.07% accuracy. The mangrove spatial distribution generated from the mRE-SR model is 1002.22 Ha with 3.24 Ha categorized as very high density, 94.82 Ha categorized as high density, 333 Ha categorized as medium density, 402.38 Ha categorized as low density, and categorized as very low density is up to 168.76 Ha.

Tingkat dan laju penurunan kualitas air di DAS Brantas Malang Raya

The decrease level of water quality of Brantas Watershed in Malang Raya was observed in this study. The aim of this study was to observe the decrease level of water quality of Brantas Watershed from Batu to Malang City. This study was carried out in the Brantas Watershed of Malang Raya (8 stations: A, B, C, D, E, F, G, and H) for 18,4 Km. The water quality parameters observed in this study were: CODmn (permanganometry), CODcr (CODmn correlation based analysis), dissolved oxygen (DO) (Winkler iodometry), TDS and electrical conductivity (EC) (EC meter), pH (pH meter), and turbidity (Turbidity meter). The result showed the value of CODmn: 1,8-10,2 mg/L, CODcr: 5,6-31,5 mg/L, DO: 4,0-6,1 mg/L, TDS: 204-289 mg/L, EC: 430-617 µS/cm, pH: 7,1-7,6, and turbidity: 2,02-10,30 NTU. There are 3 stations (A, B, and C) with 1st class water quality, 1 station (D) with the 2nd class water quality, and 4 stations (E, F, G, and H) with 3rd class water quality. The decrease of water quality in the Brantas Watershed from Batu to Malang City was up to 3 times with a decrease rate of 2,3 mg/L-1Km-1. The decomposition of organic materials in the water of Batu City and western part of Malang City is relatively better than that of central parts of Malang City which might be caused by the over capacity of recovery (Self-purification mechanism).

Merkuri (Hg) di Permukaan Perairan Muara Sungai Banyuasin, Sumatera Selatan, Indonesia

The purposes of this study were to determine the water quality, concentration and distribution of Hg in the surface water of Banyuasin river estuary. This research was conducted in June 2016 with 26 sampling stations. Measurement of in situ water quality was done using Conductivity Temperature Depth (CTD) multiparameter profiler while Hg metal was measured using Atomic Absorption Spectroscopy (AAS). The data obtained was interpolated by Inverse Distance Weighted (IDW) and then mapped spatially. The results showed that in general the water quality in Banyuasin river estuary still meets the seawater quality standards for marine biota based on KepMenLH no. 51 in 2004. The concentration of Hg in Banyuasin river estuary ranges from 0.001-0.032 mg/L with a distribution pattern that generally increases towards the ocean. The Hg concentration at the Banyuasin river estuary is on the maximum limit and exceeds the quality standard for marine biota.

Keanekaragaman dan Biomassa Ikan Karang serta Keterkaitannya dengan Tutupan Karang Hidup di Perairan Manggis, Kabupaten Karangasem, Bali

The existence of coral reef fish is closely related to the availability of coral reef resource as a habitat. Coral reef fish is a biota that has a fascination with a variety of color patterns and fascinating. Differences in coral cover conditions will affect the abundance of coral reef fish, especially those with strong linkages to living corals. This research was conducted in June - August 2017 by using line intercept transect (LIT) method for coral cover percentage and visual census method for biodiversity and biomass of coral reef fish with 3 research stations in Manggis waters, Karangasem. From the research results, it shows that the diversity index ranged between 2.54 - 2.70 which means the diversity of coral reef fish in the medium category and the stability of the community is in the medium. Furthermore, total biomass of coral reef fish ranged between 186,17 - 1692,08 kg / ha. The results stated that the percentage of live coral cover in Manggis waters ranged from 3.83% to 12.44% which means that live coral cover is categorized as bad. A very strong positive correlation between living coral conditions and coral reef fish biomass was 92.42%. Meanwhile, the relationship between living coral conditions and the diversity of coral reef fish had a strong positive correlation of 65.4%. The diversity of coral reef fish in waters is not only caused by live coral cover; however, it is caused by coral reef ecosystems that are associated in the bottom of the waters.

Efektivitas Pengolahan Limbah Domestik di Instalasi Pengolahan Air Limbah (IPAL) Suwung-Denpasar, Bali

Denpasar City and Badung Regency has a very large population growth rate, diversity, and intensity of development activities that produced domestic waste which if not properly managed, causes burden and damage to the aquatic environment. Wastewater Treatment Plant (WWTP) Suwung-Denpasar is one of the wastewater treatment business for waste management center from the area around Denpasar, Sanur, and Kuta. Based on the data analysis was known that the waste generated has not been appropriate environmental quality standards so that will affect the quality of the water. The aim of his research is to investigate the effectiveness of domestic wastewater treatment conducted in March - April 2017 by observation method in process and effectiveness measurement of waste water treatment. The processing begins with the distribution of waste in Denpasar and Sanur areas that are channeled to the bar screen and then collected to the inflow pumping station to be channeled to the receiving tank including waste from the Kuta area. Subsequent waste flows into the chamber grit to be filtered and taken to the aeration pond for 2 days then to the sedimentation pool for 16 hours and flowed to the effluent canal. The results showed the percentage of effective waste treatment in oil and fat restoration 85%, detergent 62%, and BOD 57%, while not effective in ammonia change because only reduced 26%, DO and H2S are not in accordance with environmental quality standards.

Phylogenetic Study of Zebrafish (Amatitlania nigrofasciata) as an Introduction Spesies in Buyan Lake

Buyan Lake has some fishery commodities which were often encountered include the Zebrafish (Amatitlania nigrofasciata). The origin existence of Zebrafish in Buyan Lake is not yet known then it needs study in order to know the certainty of species, phylogenetic, haplotype diversity, and phenotype characteristic. The study was conducted from January to February 2018. Molecular identification was done at Laboratory of Biodiversity Indonesia Bali. This research used quantitative and qualitative descriptive methods. Sampling was done by simple random sampling from fisherman catches. Zebrafish’s fin samples were used for molecular identification and Zebrafish’s morphological for morphological identification. The results showed that the entire sequence samples were successfully amplified with the Cytochrome Oxidase subunit I (COI) gene of 620 bp. The genetic distance in the entire Zebrafish sequences in Buyan Lake of 0 which means that the sequence of all samples are exactly similiar as species of Amatitlania nigrofasciata with the genetic distance calculation of 0. Sequence of Zebrafish in Buyan Lake is closely related to Amatitlania nigrofasciata KU568740, Amatitlania nigrofasciata KU568739, Amatitlania nigrofasciata KU568737, Amatitlania nigrofasciata KJ552531, and Amatitlania nigrofasciata KU568738 with genetic distance of 0 and has a distant relation with Rocio ostofasciata EU751752 with genetic distance of 0.113. The haplotype diversity of Zebrafish sequences in Buyan Lake showed the value of 0 which belongs to a low haplotype diversity. Black and Black Zebrafish with Red Spotted are in a different clade with Albino and Albino Zebrafish with Red Spotted with bootstrap value of 100, means they have phenotypically differences.

Kondisi dan Keanekaragaman Jenis Lamun di Perairan Pulau Serangan, Provinsi Bali

Serangan Island is one of the tourism destinations in Bali which is administratively belong to the municipality of Denpasar. Tourism development near with the segrass habitat cause the segrass ecosystem being degraded in the waters of Serangan Island. This study was aimed to determine the diversity and conditions of seagrass species which were observed from the density and percentage of seagrass coverage and to examine the effect of water quality on the percentage of seagrass coverage. This research was conducted from February to March 2017 on Serangan Island using quantitative descriptive method. Sampling was conducted at three stations by taking data and samples of seagrass, measuring water quality (temperature, salinity, pH, turbidity, substrate observation) and analyze of nitrates and phosphates content. Seven types of seagrass species were found i.e. Enhalus acoroides, Thalassia hemprichii, Cymodocea rotundata, Halophila ovalis, Halodule pinifolia, Syringodium isoetifolium, and Thalassodendron ciliatum. The study showed that the diversity index value was in the medium category. The density of seagrass was classified as very tight (condition scale of 5). The highest density was found on Cymodocea rotundata spesies at station I about 777 ind/m2. The highest percentage of seagrass coverage (79,55%) was found in station I which classified as good condition, while station II and station III were classified as damaged condition with value 13.65% and 20,79% respectively. Finally, the water quality parameters have relatively low effect to seagrass coverage percentage.

Studi Hindcasting Dalam Menentukan Karakteristik Gelombang dan Klasifikasi Zona Surf Di Pantai Uluwatu, Bali

Bali is one of the islands where there are many surf zones with various characteristics. In addition, Bali is also a heaven with a classy wave for the surfers of the world. One of the most challenging places to surf in Bali is Uluwatu Beach. Uluwatu Beach is ranked the 3rd best surf spot in the world version of CNN Travel in 2012. Wind causes sea waves, therefore wind data can be used to estimate the height and direction of the waves. Wave Hindcasting with Sverdrup, Munk and Bretschneider (SMB) method is calculated based on wind data for 10 years (2001 - 2010) from BMKG Ngurah Rai Station - Denpasar to obtain a significant wave height and period. In this research, it is necessary to approach through Hindcasting procedure, wave transformation analysis and surfing Terminology in determining the type of breaking wave and classification of surf zone in Uluwatu Beach area. Wave calculation result in Uluwatu Beach dominated by wave that coming from west side with significant wave height (Hs) of 0.98 m and significant wave period (Ts) of 5.21 s. The wave height due to the influence of wave refraction and shoaling is 0.976 m. The breaking wave height obtained from the calculation is 1.04 m at a depth of 0.849 m. From the result in this research, it can be concluded that the breaking wave type that occurred at Uluwatu Beach is plunging type according to the calculation result from its Irribaren number (0.4 <Ni <2.3). The classification of the surf zone at Uluwatu Beach based on its breakup type of wave is thought to be a good zone for surfers on intermediate level.