Observations on oceanographic parameters using remote sensing techniques intensively have been done for more than 3 decades for estimating and mapping the sea surface temperature (SST) and the abundance of phytoplankton expressed as the concentration of chlorophyll-a and applied them in studying the ocean phenomenon. As a result, the product of these 2 parameters for all over the oceans in the world has been established and available in daily basis. However, on the contrary, there is still limited application for sea surface salinity (SSS) which is also one of the most important oceanographic features. This paper describes a novel method of deriving SSS from remotely sensed ocean color. The method is based on two important observations of optical properties in regions of freshwater influences. The first is the strong effect of Colored Dissolved Organic Matter (CDOM or yellow substance) on ocean color when present in relatively high concentrations. The second is the close relationship between salinity and CDOM originating from fresh water runoff. In this paper, these relationships are demonstrated for the Jakarta Bay, Indonesia. The MODIS sensor in Terra and Aqua satellites imageries and 10 in situ measurements conducted near-simultaneously with the satellites over flight over the bay in 2004 and 2006 were implemented for deriving CDOM and SSS. The empirical relationships demonstrated in this study allow the satisfactory prediction of CDOM and SSS in the Jakarta Bay from remotely sensed ocean color. The root mean square (r.m.s) error difference between the observed and predicted parameters are 0.14 m-1 and 0.93 psu for CDOM g440 g and SSS, respectively, over a range of salinity from 24 to 33 psu. This range is in good agreement with field surveys. Parameters that may influence CDOM, such as Chlorophyll-a (CHL-a) and total suspended material (TSM) concentrations were also analyzed. Results showed that there were no relationship at all between CDOM and CHL-a, and between CDOM and TSM. These indicate that phytoplankton plays a minor role in regulating CDOM abundance, and also suggest that CDOM contribution from sediment and/or from sediment resuspension is negligible. Thus, CDOM sources in the Jakarta Bay are mainly from riverine inputs. SSS maps created from the satellite-retrieved ocean color identify features in the surface salinity distribution such as salinity front of > 32 psu that migrated in and out of the bay according to seasons. Therefore, the ability to obtain synoptic views of SSS such as presented in this paper provides great potential in furthering the understanding of coastal environments.

The coral bleaching event (CBE) which trigerred by increase in sea temperatures of 1-2˚C during El-Nino can make corals stressful or potentially dead. Many CBE research are conducted using sea temperature data measured through infrared thermal (TIR) satellite sensor. However, very few study use optical remote sensing data. This study aim to analyze the potential of optical Sentinel-2 (S-2) satellite data for monitoring during (Jun. 2016) and after (Jun. 2018) CBE in small islands of marine protected areas (TWP) of Pieh. A series image analysis procedure was conducted, i.e. simple DOS atmospheric correction; normalizating digital numbers (DN) of Blue, Green and Red bands of subject images during and after CBE to the reference image (before CBE. Dec. 2015) using “pseudo invariant feature (PIF)” approach; subtracting the DN of each bands of images during and after CBE to the reference image, and generating color composite of natural color with a contrast stretch. Result showed that this procedure can detected clearly the CBE. There was an average decreasing bleaching trend of 1.63 ha (15.8%), which indicated that some corals have recovered from thermal stress inside the TWP of Pieh. However, islands outside the TWP of Pieh, showed an increasing trend by an average of 0.50 ha (21.2%). The predation corals by the crown of thorn seastar, Acanthaster planci, whose population exploded after CBE was the main reason why CBE still detected both inside and outside the TWP of Pieh. This study shows the ability and potency of optical remote sensing data of S-2 satellite to monitor CBE, but need a lot of validation from many other sites. This result is very useful for supporting project such as COREMAP CTI.

Buku Pengelolaan Sumber Daya Perikanan Laut Berkelanjutan mengulas tentang pemanfaatan perikanan laut bagi generasi sekarang maupun bagi kepentingan generasi masa depan. Dengan kata lain, populasi ikan di laut harus dijaga agar tidak menurun akibat praktik penangkapan ikan yang dilakukan oleh manusia. Perikanan laut Indonesia memiliki potensi yang sangat besar sehingga dapat diandalkan sebagai sumber penting bahan pangan nasional, penghasil devisa negara dari hasil ekspor, penyedia lapangan kerja, serta menjadi sumber pendapatan domestik yang potensial. Jika dikelola dan dimanfaatkan secara optimal, tentu dapat membantu Indonesia dalam mencapai tujuanpembangunan nasional.Pembahasan aspek berkelanjutan menjadi salah satu kekuatan utama yang membuat buku ini bisa menjadi referensi bacaan yang patut diperhatikan oleh pembaca. Selain itu, bahasa yang ringan dan mudah dipahami juga membuat buku ini cocok untuk dibaca oleh berbagai kalangan masyarakat, seperti mahasiswa, akademisi, serta para pegiat lingkungan di komunitas lokalnya masing-masing. Selamat membaca!

Mangrove Mapping of The Lease Islands, Maluku Province Using Multi-Temporal And Multi-Sensor Of Landsat Satellite Images. Mangrove mapping in the Lease Islands, Maluku Province has been done, but using only a single date satellite image. Therefore, it is difficult to know the dynamics of their changes. The aim of this study is to map mangroves every 5 year (1985-2015) using multi-sensors (MSS, TM, ETM+ and OLI) of Landsat and field data. Supervised classification using maximum likelihood was used for classifying mangrove and other habitats, and counting their areas. Results showed that mangrove in the Saparua and Nusalaut Islands, consisted of 22 and 13 species, respectively, with the longest distribution along the cost line of Tuhaha Bay due to freshwater supplay from the surrounding river, while the rest are grown in the hardy reef flat substrates. The mean overall acurracies of the maps was good enough (74.7%), except for one Landsat-5 TM and Landat-8 OLI because of the influences of cloud cover or haze. During 30 years, the areas of mangrove are relatively stable since they are protected by local wisdom called "Kewang". The highest bias of 11.4% that made the areas of mangrove increase or decrease was not due to the utilization or conversion of mangrove, but mainly due to the influences of cloud cover/haze and the geometric differences among Landsat sensors. In the near future, the OBIA method should be try, because it seems to be able to produce mangrove maps with better accuracy.

Ikan Sidat hidup pada habitat perairan tawar (freshwater eel) yang bersifat katadromus, yaitu ikan Sidat dewasa hidup di perairan tawar (sungai, danau, perairan umum lainnya), bermigrasi jauh ke perairan laut lepas (oseanik) yang dalam untuk memijah. Pembahasan yang disajikan mengenai ikan Sidat tropis yang terdapat di peraiaran Indonesia dengan penekanan khusus yang mendalam pada kehidupan awal ikan ini, yakni pada fase larva atau leptocephalus. Pembahasan dimulai dari keanekaragaman ikan Sidat, ikan Sidat tropis Indonesia. Ada empat fase kehidupan ikan Sidat, yaitu fase leptocephalus (larva), glass eel/elver, yellow eel, dan silver eel. Buku Kehidupan Awal Ikan Sidat Tropis Indonesia hadir untuk mengenalkan, menginformasikan, dan memberikan wawasan kepada masyarakat mengenai kehidupan ikan Sidat di perairan Indonesia. Buku ini dapat menjadi bahan bacaan menarik untuk memperluas ilmu pengetahuan kita dan dapat menjadi bahan rujukan pembaca umum maupun pembaca khusus yang berkecimpung di bidang biologi laut, khususnya ichthiology.