Table of contents

Foreword

The Banda Sea was the object of research activities since the 20^th century, starting from expeditions carried out during the 1950s. One of the most prominent expeditions ever accomplished in this water was the Snellius Expedition. A joint collaboration between research scientists from Dutch NIOS and the Indonesian Institute of Science (LIPI) Ambon Office, this expedition resulted in the publication of three volumes of substantial findings. These findings have helped to shape the knowledge and information of this tropical deep-sea. LIPI scientists published an oceanology atlas in 1999, but not much afterward was done to compile and critically review what has been done fifteen years after.

The Center for Deep-Sea Research (PPLD), Indonesian Institute of Sciences (LIPI) has held successfully an International Symposium on Banda Sea Ecosystem (ISBSE) 2017 in Balai Kartini Jakarta on October 23rd, 2017. This International Symposium -the first about this particular ecosystem- was designed to carefully review what has been done in the past sixty years, their scientific contribution to the current understanding of this water, and what perspective gained from these research activities for the future management and conservation of its resources. Designed to be a one-day plenary lecture, this event was included in the Conference Series as one of the main activities of Indonesia Science Expo (ISE 2017), within the celebration of LIPI 50th establishment entitled LIPI contribution in building the nation.

List of Editorial Committee and Scientific Committee are available in this PDF.

List of Photos are available in this PDF.

All papers published in this volume of IOP Conference Series: Earth and Environmental Science have been peer reviewed through processes administered by the proceedings Editors. Reviews were conducted by expert referees to the professional and scientific standards expected of a proceedings journal published by IOP Publishing.

Attention to the deep-sea ecosystem research in order to achieve blue economy goals is low. The Banda Sea is important deep-sea ecosystem in Indonesia and it was identified as a global marine mega-biodiversity site. The objectives of this paper are 1) to document the history, achievements, and challenges of deep-sea research development and 2) to develop a grand design and innovative strategic plan for deep-sea research. Literature reviews and questionnaire survey for scientists across Indonesia were carried out. The literature reviews indicated that deep-sea ecosystem is not well documented. Few articles on deep-sea were published (mean 0.8 article y⁻¹) which were mainly focused on geological (45%) and physical oceanography (32%), less research on biological (16%) and chemical oceanography (8%). Deep-sea ecosystem faced tremendous threats due to ecosystem degradation, pollution, and climate change. The questionnaire survey showed that research infrastructure/facilities (Ranking 1) and institutional management systems (Ranking 2) were the main obstacles to Indonesian deep-sea research development. A grand design named Indonesian Deep-sea Research and Monitoring (I-DREAM) and its strategic plan were developed to achieve blue economy goals. Strengthening research infrastructure and institutional management systems are the top priories that should be achieved in the short-term period to support deep-sea research in Indonesia. Scientific pursuit in long-term period should be focused on biodiversity and deep-sea ecology including chemical oceanography (24%) and its interaction with other ecosystems and atmosphere (18%) were identified as the top priorities to be implemented for future research (Ranking 1 and 2). The Banda Sea was identified as a suitable core study area of the I-DREAM's pilot project. The grand-design and its innovative strategic plan are essential to fulfilling high demand on a guideline for deep-sea research to achieve blue economic development goals.

Studies on marine bacteriology in the Banda Sea were started from the 1950s. This paper is an attempt to review all works carried out in the last seven decades. Literature reviews indicated that there was not much research done on marine bacteria in the Banda Sea and adjacent waters such as Ambon Bay. Studies on bacterial biomass, indicator bacteria on water quality monitoring as well as bacteria potential as a producer of secondary metabolites were carried out. However, considering Banda Sea ecosystem that is mostly consisted of deep environments, it would be interesting to prioritize research activities on piezophiles or at least piezotolerant marine bacteria. There is thus an urgent need to determine the priorities in studying marine bacteria in this ecosystem, which should be focused on deep-sea ones.

A list of Echinodermata fauna recorded from the Banda Sea has been compiled from the literature published between 1889-1995 as well as from the LIPI-RCO reference collection. To date, 44 species from five extant classes (Asteroidea, Ophiuroidea, Crinoidea, Echinoidea, and Holothuroidea) have been recorded from this area that consisting of the epipelagic (< 200 m depth), mesopelagic (200-1000 m depths) and bathypelagic (> 1000 m depth) species. Research history, taxonomy, and depth distribution are briefly discussed here. However, deep-sea habitats all over the world remain unexplored, including the Banda trench. The opportunity to discover both new records and new species for science from this trench is still wide open since the hitherto record of its marine biodiversity is still a few compared to the discovery on the shallow water. More deep-sea exploration will be needed to improve our knowledge of marine biodiversity.

Tuna exploitation in the Banda Sea was started when the Indonesian government gave access to the Japanese fleet under the bilateral cooperation of the Banda Sea Agreement (BSA) in 1975-1980. Several studies were conducted afterward in revealing the magnitude of tuna resources in the Banda Sea. In this paper, we reviewed the tuna studies that were done in the Banda Sea over the periods of 1980-2017 to improve our understanding on the biology and ecology of tuna in the region as the basis for future studies. Overall, we reviewed 29 publications consisted of eight research themes; biodiversity (5), catch composition (8), fish aggregating device (FAD) (2), fishing ground (2), growth-population (3), harvest-effort strategy (4), reproduction (4), and tagging (1). The Snellius II expedition in 1984-1985 was a remarkable study covering almost whole area of the Banda Sea. The study of catch composition and biodiversity were dominant in recent decade indicating there was urgent need to manage the tuna fisheries in the Banda Sea to preserve the tuna stock. Since the Banda Sea is considered as a tuna conservation area, the future studies should be focussed on the scientific findings to support the regulation.

The Banda Sea is a collage of young oceanic basins and fragmented Australian continental crust located at the heart of the Australia–SE Asia collision zone where Australian and Asian biogeographic regions converge. The formation of the sea was governed by the southeastward rollback of the Banda Slab since c. 16 Ma, which in its wake opened new oceanic basins and extended and fragmented Australian crust. These Australian crustal fragments are today either stranded within the Banda Sea where they form the prominent submarine 'Banda Ridges', or now reside as thrust-sheets on the NW Australian shelf after being transported all the way to the southern Banda Arc. The deepest part of the Banda Sea, the 7.2 km Weber Deep, was formed by extreme lithospheric extension that occured in the latter stages of Banda Slab rollback. This extension was accommodated by the vast low-angle 'Banda Detachment', which operated above the subducted fringes of the Australian continental margin.

The Banda Sea region which includes the Moluccas and Nusa Tenggara consists of 3,478 small islands separated from each other by deep seas. This region can be regarded as the most complex energy supply chain in Indonesia due to geographic condition and lacking of energy infrastructure. The newly issued Indonesian general plan of energy aims to establish a strategy for planning the region's energy mix until 2050. By then, national primary energy should not be dominantly supported by oil and gas, and renewable energy should contribute 31%. In addition, government has committed to attain near 100% electricity ratio by 2020. Recent hydrocarbon discoveries and ocean energy mapping indicate that the Banda Sea region is an attractive area where the country's primary energy needs may partly be fulfilled. However, the region's sustainability in energy production still has to be established with greater efforts. Hydrocarbon search has been discouraged by the geologically risky nature of the region. The implementation of renewable energy, particularly ocean energy, is hampered by technology immaturity and constraining operational rules and policies.

Anthropogenic pressure can cause serious problem in the marine environment, such as marine pollution. In this paper the existing scientific literatures related to marine pollution study that had been conducted at the Banda Sea were reviewed. There were in total 22 publications found that specifically addressed the marine pollution at the Banda Sea. The majority of case studies were conducted in shallow coastal waters. Few data discussed about deep-sea waters. We highlighted knowledge gaps regarding the information on data from Banda Islands coastal area. The final goal of this paper is to recommend the future studies that need to be conducted in the Banda Sea waters.

The Banda Sea ecosystem has been highlighted in the past decade for its potential role in providing economically important fish stock for human consumption. However, literature studies indicated lack of references regarding fish larvae abundance and composition in coastal areas of islands impacted directly by the Banda Sea. The study covers fish larval survey carried out at the northern waters of Ambon Island in April 2017. The composition, distribution, and abundance of fish larvae were described based on five horizontal and one vertical sampling stations. Twenty-eight families were identified and two of them were the most abundant: Atherinidae (23% of the total larvae) and Apogonidae (21% of the total larvae). Most of the other families were known to be neritic and in particular were fishes commonly found to be associated with coral reef ecosystems. This finding indicated the profile of the northern waters area, which has extensive coral reef coverage, as well as estuary and mangrove area.

Located in the Indonesian fisheries management area (WPP) 714, the Banda Sea has a high potential of fisheries resources. However, information about reef fish resources is limited. This study aims to assess the Banda Sea reef fish diversity, abundance, and stocks. The diversity, abundance, and density of three reef fish groups (indicator, target, and major) were assessed using underwater visual census (UVC) from 287 sites. A stock assessment was done by multiplying fish habitat areas and fish density. There were 287, 42, and 301 species of target, indicator, and major groups recorded respectively. High abundances were found in Banda Islands and the Southeast region, while the lowest abundance was in the Kendari waters. The average density of indicator and major groups were 0.251 and 4.519 individuals.m⁻², with estimated stocks of 2,883 × 10⁶ and 51,899 × 10⁶ individuals (ind.) respectively. The density of target group fish which has economic values was 1.976 ind.m⁻², equivalent to the biomass of 599.6 ton.km⁻² with stocks of 4,214,468 tons. Despite huge reef fish resources supporting the local livelihood, the stock tended to decrease in 2009-2012 and 2015-2016 in Flores and Banda Islands. Therefore, conservation and sustainable use of reef fishes of the Banda Sea is required.

The Banda Sea region is situated in the Wallacea biogeographical area, known as one of the biodiversity hotspots of the world. The region harbours various types of ecosystems, ranging from mangroves and coral reefs to seaweeds, indicating its potential for harbouring organisms that produce bioactive compounds, such as sea cucumbers, soft corals, and tunicates. While many studies have been carried out on the first two organisms, much lesser is known about the latter one, notably in this region. The assessment is our first attempt to explore the tunicates found in northern coastal waters of Ambon Island, an area that is a part of the Banda Sea. Two types of tunicates were obtained during the survey, namely the violet-green and white-yellow variants of solitary tunicates Polycarpa aurata (15 specimens) and social ones of Didemnum molle (3 specimens). The Polycarpa specimens' heights ranged from 2.5 to 4.8 cm with wet weights from 9.4 to 28.03 g, and the Didemnum ones were of 1.2 - 2 cm and wet weights from 1.2 to 5 g. Feeding experiment indicated that low volume (5-10 ml) of pure cultures such as Dunaliella sp., Nannochloropsis sp. and Tetraselmis sp. in small aquarium (40 x 60 cm) resulted in good survival rate for Polycarpa aurata collected from northern Ambon Island waters. Rearing experiments in a discontinuous aquarium setting using solitary tunicates indicated the following requirements: thorough cleaning of the tanks, regular feeding intervals, and regular cleaning of each tunicate. The regular cleaning of mucous at the external part of tunicates is indispensable to ensure the wellbeing of the organisms.

The Banda Sea is a sea in the eastern part of the Indonesian archipelago, connected directly to the Pacific Ocean and surrounded by hundreds of small islands that create its unique characteristics. A large portion of Pacific seawater is passed through the Banda Sea to the Indian Ocean forming an Indonesian through flow (ITF), an ocean current with importance for global climate. The ITF provides a low-latitude pathway for warm, fresh water to move from the Pacific to the Indian Ocean and serves as the upper branch of the global heat conveyor belt. Despite its importance in the global ocean and climate system, detail study and discussion of the Banda Sea are scarce. Here, we discuss the physical properties in term of temperature, salinity and density in conjunction with nutrients distribution in seawater from 17 stations of the Banda Sea using the direct observation data of the research cruises that were gathered by Reid and Mantyla. The available numerical data of the Banda Sea were then visualized using Ocean Data View software. To the best of our knowledge, it is the first report for a detailed discussion of this kind in the Banda Sea. The results show that nutrients concentration depleted in surface water (0 – 500 m) and enriched in deep water (500 m – bottom). The concentrations ranges of phosphate, nitrate and silicate were 0.3 – 3.1, 0.5 – 40 and 1 – 147 μmol l⁻¹, respectively. As shown from temperature, salinity and density profiles, it is known that the inflowing seawater from the Pacific Ocean into the Banda Sea is gradually modified which change the upper water masses (0 – 250 m) characteristics that eventually outflows into the Indian Ocean.

El Niño and La Niña are disruptions to the ocean-atmosphere system in the equatorial Pacific area, with significant impacts on the climate and weather throughout the world. This paper discusses the possible impact of El Niño and La Niña to the water mass circulation in Ambon bay which is directly adjacent to the Banda Sea. We used observed vertical temperature variability data in June, July, September, and October in the year of 2008 (neutral year) and 2009 (El Niño year), and July and October 2010 (La Niña year). All data have been taken with CTD instrument in 7 stations which are aligned in one straight line from inner to Ambon Outer Bay (AOB). The result shows that the water mass circulation in Ambon Bay may be affected by El Niño and La Niña. El Niño phase makes the thermocline layer from the Banda Sea to become shallower than usual and thus makes the circulation in Ambon Bay more rigorous. This is because the water mass with higher density can enter into the deep Ambon Inner Bay (AIB) through the narrow sill which separates the Ambon Bay inner from outer parts. La Niña, on the other hand, weakens the water circulation because the thermocline layer becomes deeper than usual.