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Komplek Gunung api Ijen merupakan prospek panas bumi yang terletak di Kabupaten Bondowoso, Jawa Timur. Sistem panas bumi Gunung api Ijen ditandai oleh kawah danau berfluida asam dan solfatara bertemperatur tinggi. Beberapa batuan teralterasi di dekat Gunung Kukusan dan sekelompok mata air panas Blawan di bagian utara kaldera. Pengukuran magnetik dilakukan pada 175 titik tersebar di dalam kaldera melingkupi kawah Gunung Ijen hingga Gunung Merapi. Anomali intensitas magnetik total diperoleh melalui koreksi standard IGRF dan variasi diurnal. Metode reduksi ke kutub (RTP) diterapkan dengan inklinasi geomagnet sekitar -32°. Secara umum, hasil penelitian menunjukkan bahwa anomali magnetik tinggi berasosiasi dengan jalur patahan yang menghasilkan pembentukan gunung api baru di bagian selatan, Sedangkan anomali magnetik rendah berada berdekatan dengan kawah Ijen dan Gunung Merapi di bagian timur. Anomali yang rendah ditafsirkan oleh dua kemungkinan pengaruh demagnetisasi batuan akibat kontak termal atau pengaruh remanen batuan dengan umur geologi tertentu menghasilkan polaritas reversal. Anomali intensitas magnet total tinggi pada komponen regional berada 50 hingga 114 nT dan anomali rendah berada di kisaran -850 hingga –750 nT, hal ini ditafsirkan bahwa potensi batuan panas di Komplek Gunung api Ijen tersebar sesuai keberadaan kaldera dan jalur gunung api muda. Prospek batuan panas berkorelasi dengan Formasi batuan gunung api muda dan intrusi magmatic hasil proses pembentukan gunung api berumur Kuarter.

Soil characteristics are important impact for the scale of damage caused by earthquake vibrations. The impact caused by an earthquake in a location depends on the shear wave velocity (Vs). The study examined the effect of sedimentary rock formations on shear wave velocity and site class based on SPT tests in two rock formations in Bandar Lampung. The value of Vs, Vs30 and site class is determined based on the N-SPT value. Older rock formations of Quaternary age, have produced compaction at a shallow depth of 2 m from the surface, with Vs30 360 m/s and site class C. While the formation is younger, compactions are formed at a depth of 20 m, Vs30 200 m/s and site class D.

Alginate is rich in bioactive compounds and has been known to act as a stimulator on the innate immune system. The objective of this study is to determine polysaccharide and oligosaccharide alginate yield, that percentage inhibition with a different type of extraction, to evaluate growth performance as well as immune response by oxygen stress tolerance. Thermal heating with oven laboratory at 140oC for 4.5 hr was done to breakdown the polysaccharide into oligosaccharide. The extraction was conducted by maceration, filtration, precipitation, and centrifugation. Factorial design with two factors was implemented to 260 Zebrafish and reared in thirteen aquariums (20 fish per aquarium) for 12 days. Zebrafish was fed at different dose (4.0g; 6.0g; 8.0g.kg-1) and different type of extraction [noEDTA/noKCl; KCl; EDTA and (EDTAandKCl)]. The evaluation of radical scavenging activity was done spectrophotometrically at 515 nm. Results showed that the highest alginate yield either polysaccharide or oligosaccharide was gained from KCL treatments, percentage inhibition (82.61%), growth performance as well as tolerance of stress (P

Regional Painan, the distric of Pesisir Selatan, the province of west Sumatera is one of the areas with high risk disaster prone. This study aims attempts to maped the disaster prone area of the Painan region based on the dominant frequency value, Vs30, PGA and amplification and to know the value of ground movement from the area. By using the HVSR method (Horizontal to Vertical Spectra Ratio) expected to assist to zone the regions. Based on the research that has been done, it is known that the Painan area, West Sumatera, have values of dominant frequency between 0.6 to 12.07 Hz. As for the value Vs30 between 73.08 to 1449 m/s and the amplification values between 0.47 to 6.01. The PGA value for Painan region between 0.034 to 0.063 g. Based on the analysis that has been done by correlating the four zoning map, it is known that the area which has a high risk of earthquake disaster that is estimated to coastal areas. This is supported by the dominant low frequency value and the value Vs30 small and PGA of high value. The amplification value of this region is divided into four zones, areas that have amplification is very high being around the beach and composed by rock alluvial, the value of amplification of high contained in nearly all the regions Painan while amplification medium and low are the small area of Painan and the small area of Bungo Pasang Salido because based on the geological map of the area is composed of two types of rocks are alluvial and rock Painan Formations.

Bandar Lampung is one of the cities in Indonesia, which has a potential to land subsidence due to the extraction of ground water, mining, land conversion, and geological conditions. For that reason, carried out the study of land subsidence with SBAS technique, due to the very lack of information about the symptoms of land subsidence in Bandar Lampung. In this study, 15 SAR data in 2006 to 2011 used and then combined to produce 40 interferogram then inverted resulting in a time-series deformation and deformation speed average. Velocity precision obtained with SBAS technique is highly dependent on the type of land cover in the study area, but it is known that the average of land subsidence in Bandar Lampung is about 0.06 mm/year, which is considered quite stable due to the geological structure that does not allow for the occurrence of massive consolidation process. Several areas have indications of subsidence 5 mm/year are suspected to be caused by tectonic activity and human activity (industrial, mining, extraction of groundwater, and land conversion), which then has implications for structural damage to buildings, flooding in coastal areas, and landslides in hilly areas.

Research has been conducted in Kepahiang area using gravity data with the aim of identify faults based on analysis of the Second Vertical Derivative (SVD) and interpreting structure sub-surface of the based on 3D inverse modelling from Bouguer anomaly and residual anomaly. The research area have an Bouguer anomaly between 38 mGal - 74 mGal, where the high Bouguer anomaly value has a value range of 63,2 mGal - 74 mGal located in the southwest direction of the research area. Whereas the low Bouguer anomaly value has a range of values 38 mGal - 47 mGal located in the north of the research area. To know the existence of fault structure in research area, conducted filtering Second Vertical Derivative (SVD) on the map Bouguer anomaly, regional and residual. The structure faulting is shown with contour of zero and between the contours of high and low. From the analysis of SVD complete anomaly Bouguer and SVD residual anomaly there are 8 (eight) faulting, while from SVD regional anomaly there are 4 (four) fault. 3D inversion modeling of the residual anomaly was done to prove the existence of the fault analyzed based on filtering Second Vertical Derivative (SVD). Based on the results of inversion 3D residual anomaly been gained one (1) reservoir in a northern direction research area and two (2) in the direction of west the research area by a contrast the density of -0,0719356 gr/cc until -0,236053 gr/cc with a depth of 0 meters up to 4.705 meters.

The research had been performed using Magnetotelluric to get a 2D model based on variations in resistivity of the subsurface rock. The purpose of this study was to determine the hydrocarbon formation zone. The research method to achieve the research objectives, among others, the first filtering performed on the data with a robust process. This process consists of Robust No Weight, Robust Rho Variance and Ordinary Cohenerency. The second step is done to change the format Selection XPR And Edi. A third inversion resistivity model for the review get a 2D cross section. Based on the findings of the eight data processing methods of measurement points obtained information Magnetotelluric rock formations. Formation hidrokrabon What are the areas is research a reservoir and caprock. The layer in 1600 m – 2700 m depth from the surface which resisvity 12 -33 m assumpted as clay cap. While the layer in 2700 m – 5000 m depth from the surface with high resistivity 41- 250 m is assumpted as oil sands (reservoir). The trap zone of this hidrocarbon formation categorized into structural trap which is the trap of anticline.

The research area "Y" is an area of gold mineralization with low sulfidation epithermal type deposit. The existence of this type of mineralization on the path marked by the presence of mineral deposits, which form the quartz veined below the surface of the deposited within the structure of the fault. In this study, analysis of gravity data using derivatives analysis, i.e. First Horizontal Derivative (FHD) to determine the boundary fault structure and Second Vertical Derivative (SVD) to determine the type of fault. The existence of the fault structure integrated with subsurface modeling results in two-dimensional and three-dimensional. The results showed three line slice made in the area of research, identified structure of down faults (normal) trending northeast - south on slice 1 with an estimated dip (slope) is 22° and expected of strike on this fault is N 158° W and thrust fault structure trending northwest - south on slice 2 also slice 3 with an estimated dip (slope) is 22° and expected of strike on this fault is N 158° E. The results of the modeling of two-dimensional and three-dimensional show fracture structure is at the density of 2 g/cc – 2,67 g/cc in the depth of around 100 m - 250 m that consists of sedimentary rocks (clay and sandstone) with a density of 2,2 g/cc – 2,3 g/cc at the age of Tertiary Pliocene, tuff rock with a density of 2,4 g/cc – 2,5 g/cc at the age of Early Miocene and bedrock (basement) in andesite form with a density of 2,67 g/cc.

Research area is located in Padang Cermin Sun-District, Pesawaran Regency, Lampung Province. Manifestation in research area is hot water pool with surface temperatures reach 900C. Data acquisition has been done by Wenner-Schlumberger configuration with 5 acquisition line. Line 1, line 4 and line 5 have 280 meters length. Line 2 have 240 meters length and line 3 have 320 meters length with a spacing of each electrodes in each lines is every 5 meters. The objective of this research are (1)examining the geochemical contaminant and fluid types, (2)identifies the geothermal fluid based on 2D and 3D resistivity data analysis, also (3)identifies the layer of rock in Padok manifestation area based on 2D and 3D subsurface resistivity section. Subsurface lithology in research area generally divides into 4 parts. Which is hot water fluid with mean resistivity value between 1 Ωm into 3 Ωm and based on geochemistry data the fluid type is chloride water; surface sediment with resistivity value between 6 Ωm into 50 Ωm and identified as swamp sediment and alluvium sediment divides into gravels, pebbles, sands, clay and peat; Gravels, pebbles, sands, clay and peat with resistivity value between 50 Ωm into 100 Ωm; and igneous rock (andesite-basalt) with resistivity value more than 100 Ωm.

The research of gravity on Suwawa Sub-District geothermal is done for the purposes to determine fault structure using Second Vertical Derivative (SVD) technique, create a 2D subsurface model and 3D tentative model using regional anomaly data, and interpreting Suwawa geothermal system. Data processing is done in the research include: drift correction, terrain correction, free air correction, complete Bouguer anomaly, spectral analysis, SVD analysis, 2D modeling and 3D inversion modeling and tentative model. The research results showed that the research area has low Bouguer anomaly with a range of 75.8 to 79.5 mGal values in the West and Southeast, while high anomaly with a range of 90.9 to 111.2 mGal values in the Northern and Southern, there is correlation of fault based on SVD analysis with geological fault that indicate the presence of Libungo hot springs, the inversion results indicate the presence of low density (ρ = 1.8 g/cc) which is an alluvial rocks and high density (ρ = 2.9 g/cc) which is Andesite Lava rocks, 3D tentative modeling indicate the presence of reservoir is at a depth of 2 km from the ground surface. Based on the model created, Cap Rock is located on Andesite Lava rocks with ρ = 2.9 g/cc at a depth of 1200 m and Heat Source located at a depth of 2000 m.

Soil mechanical research has been done in Cilacap Regency using DSHA method and microtremor data. This study aims to analyze the local land response to earthquakes based on the dominant frequency parameters (f0), amplification factor (A0), wave velocity VS30 and seismic hazard analysis through deterministic approach. This research uses 193 microtremor measurement points using a short period TDS-303 type (3 component) seismometer. Microtremor data were analyzed using the Horizontal to Vertical Spectral Ratio (HVSR) method in geopsy software. DSHA analysis refers to the source of the Lembang Fault earthquake and Java Subduction zone for deterministic calculations. Based on the analysis of HVSR method, Cilacap Regency is located on land type 1 (frequency 0-1.33 Hz) and soil type 2 (frequency 1,33-5 Hz) according to Kanai Classification (1983), dominated amplification value 1,104 to 8,171 times, then Dominated by soil class E (VS30 value 183 m / s) and soil class D (183 m / s VS30 366 m / s) according to NEHRP Classification (2000). This indicates that Cilacap Regency has high vulnerability to earthquake disaster. Based on the estimated value of PGA calculation method of DSHA, from the calculation of earthquake source Subduction obtained Java PGA bedrock 0,045 g - 0,0671 g and PGA surface rock 0,1926 g - 0,4855 g and calculation of Lembang Fault obtained PGA bedrock 0, 09 g - 0.025 g and PGA surface rocks 0.017 g - 0.089 g. Based on risk map analysis (combination of dominant frequency analysis, amplification, susceptibility factor and ability factor), the highest risk areas are Kec. Adipala, Kasugihan, Binangun, Nusawungun, Cil. Middle, Cil. South, Cil. North, allegedly the soil layer constituent area is a layer of thick and soft sediments. While the low risk of Kec. Majenang and Dayeuh Luhur.

Kota Baru is the satellite city of Bandar Lampung. The city is prepared for the expansion of the city of Bandar Lampung. Zonation map of earthquake risk is required for Kota Baru due to its location within the reach of earthquake energy of Semangko subduction fault. In this study, we model the earthquake-prone zone map based on the soil characteristics (site effect) combined with the underground layer model to get a detailed description of the horizontal and vertical soil character. The microtremor method is performed to obtain the zonation effect mapping. Whereas, the ground layer modeling is obtained using the geoelectrical method. The modeling results show that the study area is far from tectonic activity based on the history of past earthquake events. However, this area has a large sediment thickness and has a low dominant frequency value, so it is an area that is vulnerable to earthquakes.

Penelitian ini betujuan untuk menguji penggunaan aerasi microbubble pada parameter kualitas air, performa, nilai NVC dan factor kondisi perairan. Ikan berukuran 12±3 g, sebanyak 50 ekor dipelihara selama 3 bulan dengan perlakuan aerasi micobubble, aerasi konvensional dan non aerasi dalam system resirkulasi. Parameter yang dianalisa dalam penelitian ini menunjukkan nilai DO aerasi microbubble lebih tinggi dan tetap bertahan lama sampai akhir penelitian dibandingkan aerasi konvensional dan control (p

Abstrak Pesisir Kulon Progo saat ini memiliki habitat mangrove dan lahan tambak udang. Perkembangan salah satunya, akan mengakibatkan berkurangnya luas lahan yang lain. Penelitian ini bertujuan untuk (1) menganalisis kondisi fisik wilayah pesisir Kulon Progo, (2) menentukan zona yang sesuai untuk kawasan mangrove dan/atau tambak udang di wilayah pesisir Kulon Progo, dan (3) menyusun rekomendasi pengelolaan kawasan mangrove dan atau tambak udang di wilayah pesisir Kulon Progo. Pengambilan sampel dilakukan dengan purposive sampling. Data kondisi fisik lahan diperoleh melalui observasi dan pengukuran di lapangan. Zonasi kawasan mangrove dan tambak udang dilakukan dengan reinterpretasi peta dan metode matching dengan parameter kesesuaian yang telah ditentukan sebelumnya. Strategi pengelolaan kawasan mangrove dan tambak udang dilakukan dengan menganalisis faktor internal dan eksternal wilayah menggunakan analisis SWOT. Hasil penelitian menunjukkan bahwa kondisi fisik wilayah pesisir Kulon Progo terdiri atas substrat dasar berbatu, lempung bergeluh, lempung, lempung berpasir, berpasir. Pasang surut air laut berkisar 1-1,1m, salinitas air antara 0-29‰, kecerahan air antara 0 cm - tidak terukur, dan suhu air antara 27-34,1 °C. Kondisi fisik pesisir Kulon Progo ada yang sesuai (S2) untuk pertumbuhan mangrove dan tambak udang, serta ada yang tidak sesuai untuk keduanya. Zona yang sesuai (S2) untuk kawasan mangrove terdapat di muara Sungai Bogowonto seluas 1,58ha. Zona yang sesuai (S2) untuk kawasan tambak udang seluas 134,49ha. Strategi pengelolaan kawasan untuk zonasi mangrove di lokasi kajian yang dapat direkomendasikan dalam penelitian ini antara lain (1) pelestarian dan pengembangan kawasan mangrove dalam bentuk kawasan konservasi sekaligus sebagai objek wisata dan pendidikan, (2) mengembangkan dan meningkatkan komitmen masyarakat atas arti penting kawasan mangrove untuk menghambat alih fungsi kawasan mangrove, (3) mengembangkan zona mangrove dengan menanam jenis mangrove yang sesuai dengan kondisi fisik lahan, (4) melakukan tindakan persuasif dalam mewujudkan konsensus masyarakat untuk membentuk kawasan lindung mangrov Abstract The Coast of Kulon Progo is currently the habitats for mangroves and shrimp ponds, i.e., where the development of the former reduces the latter. This research aimed to (1) analyze the physical condition of the coast, (2) determine the suitable zone for mangrove areas and/or shrimp ponds along the coast, and (3) propose a recommendation for mangrove and/or shrimp pond management along the coast. The samples were selected using purposive sampling technique. The research also employed field observation and measurement to acquire the physical condition of the land. The zonation of mangrove area and shrimp pond was obtained from map reinterpretation and matching technique with the predefined parameters of land suitability. As for the mangrove and shrimp pond management strategies, the research used SWOT analysis to study both of the internal and external factors in the study area. The results showed that the substrate of the coast was composed of rock, clay loam, clay, sandy clay, and sand. Aside from the substrate, the physical condition of the coast was characterized by sea tide (1-1.1 m), salinity (0-29%), water transparency (0 cm-undetectable), and temperature (27-34.1°C). These characteristics classified the coast into two types of suitability for mangrove growth and shrimp pond development, namely suitable (S2) and unsuitable. While the suitable (S2) zone for mangrove development occupied 1.58 ha area in the mouth of Bogowonto River, the suitable (S2) zone for shrimp pond was considerably larger, i.e., 134.49 ha. The recommended strategies for mangrove zone management in the study area are as follows: (1) mangrove preservation and development as a conservation area and an object for tourist destination and education, (2) the encouragement and improvement of community’s commitment to accentuating the essential functions of mangrove areas and to decelerating any land use conversions of mangrove zone, (3) the development of mangrove zone by planting suitable mangrove species with the physical condition of the area, and (4) the implementation of persuasive actions in actualizing community consensus on mangrove area development.

ABSTRAK Kajian mengenai analisis kandungan nitrogen (N), fosfor (P) dan karbon organik (KO) telah dilakukan di Danau Sentani, Papua. Penelitian ini bertujuan untuk mempelajari kandungan ketiga unsur tersebut di perairan. Metode penelitian yang digunakan adalah metode survei berstrata (stratified sampling method) sesuai dengan tujuan (purposive). Metode pengukuran dan pengambilan sampel menggunakan teknik Composit Sampling. Area penelitian dibagi atas 4 zona yaitu inlet, KJA, tengah danau dan outlet. Analisis data menggunakan Program Microsoft Excel 2007 dan Analisis Varians (ANOVA) pada taraf kepercayaan 90%. Hasil penelitian menunjukkan bahwa rasio N:P perairan danau adalah 10,248 mg/L/bln di inlet; 2,417 mg/L/bln di KJA; 0,683 mg/L/bln di tengah danau dan 8,351 mg/L/bln di outlet. Sementara itu, rasio C:N adalah 15,008 mg/L/bln di inlet; 47,647 mg/L/bln di KJA; 90,884 mg/L/bln di tengah danau dan 6,777 mg/L/bln di outlet. ABSTRACT Study on the analysis of nitrogen (N), phosphorus (P) and organic carbon (OC) content has been conducted at the Lake Sentani, Papua. This research aims to study the content of the three elements in the waters. This study using stratified sampling method in accordance with the purpose. Methods of measurement and sampling using Composite Sampling. Study area was divided into four zones, namely the inlet, netcage culture, the middle of the lake and outlet. Data analysis was done by using Analysis of Variance (ANOVA) at 90% confidence level. The results showed that the N:P ratio in the water are 10, 248 mg/L/month in the inlet; 2.417 mg/L/month in the netcage culture area; 0.683 mg/L/month in the middle of the lake and 8.351 mg/L/month at the outlet. Meanwhile, C:N ratio are 15.008 mg/L/month in the inlet; 47.647 mg/L/month in netcage culture; 90.884 mg/L/month in the middle of the lake and 6.777 mg /L/month at the outlet.

ABSTRAK Penelitian mengenai konsentrasi nitrogen (N) dan fosfor (P) dilakukan dengan tujuan untuk mengevaluasi tingkat eutrofikasi dan pencemaran air, menghitung neraca N total dan P total serta melakukan pengendaliannya menggunakan perikanan. Penelitian dilakukan menggunakan metode survai, yaitu melakukan pengambilan sampel dan pengamatan air secara purposive. Pengambilan sampel air di daerah waduk (hulu, tengah dan hilir waduk) dan daerah sungai (sungai masuk dan sungai keluar). Di daerah waduk diamati pada jeluk air: 0 m, 2 m, 4 m dan dasar. Pengambilan sampel air dilakukan tiap bulan, mulai Juni 2006 sampai Mei 2007. Vanabel penelitian meliputi: amonia, amonium, nitrit, nitrat dan fosfat; N total dan P total, suhu air, kekeruhan, TDS, TSS, O, terlarut, pH, CO, bebas, alkalinitas dan plankton. Eutrofikasi air oleh N dan P dianalisis secara diskriptif dan tingkat pencemaran air dihitung menggunakan Indeks Pencemaran (lP) yang disyaratkan PP RI Nomor 82. Neraca N total dan P total dihitung dengan input-output, sedangkan pengendaliannya menggunakan metode simulasi. Hasil penelitian menunjukkan bahwa eutrofikasi pada tingkat eutrofik sampai hipereutrofik, pencemaran air masih tergolong ringan di daerah budidaya ikan dan waktu konsentrasi P maksimum; budidaya ikan menggunakan KJA jaring ganda, penebaran dan pemanenan ikan di luar KJA dapat mengurangi residu dan beban N total dan P total. ABSTRACT The research of nitrogen (N) and phosphorus (P) in Sermo reservoir aimed to evaluate water eutrophication and pollution, to calculate N total and P total budget and to control its concentration using fisheries. The research was conducted by direct observation and measurement on water samples taken from inflow and outflow rivers, upstream, middle and downstream areas of reservoir. The samples is reservoir were taken at water depth: 0-2,4 m and the bottom. Observation was done monthly from June 2006 up to May 2007. the variables were ammonia, ammonium, nitrite, nitrate and phosphate concentration, N total and P Total, water temperature, transparency, turbidity, total dissolved and suspended solids, dissolved O2, alkalinity and plankton. The research conclude that eutrophication level varies from eutrophic to hypereutrophic, light pollution was found in fish culture area and when the highest concentration of P, controlling of N and P by fish culture using double nets, fish stocking and harvesting in outside net cage may eliminate residue and decrease loading of N total and P total in the water