Seagrasses are one of the most productive ecosystems in coastal areas and support a wide variety of associated fauna. The tropical Indo-Pacific region is considered to have the highest diversity of seagrass plant spec...Seagrasses are one of the most productive ecosystems in coastal areas and support a wide variety of associated fauna. The tropical Indo-Pacific region is considered to have the highest diversity of seagrass plant species and the largest distribution areas of seagrass, yet the seagrass macrofauna in this region are poorly understood. To help fill this gap in our knowledge, an ecological survey was conducted to describe the abundance and diversity of benthic macrofauna from tropical seagrass beds and to determine between-station variations within a transect and between-site variations in macrofaunal abundance, taxa richness and community structure. Benthic macrofaunal samples associated with seagrass beds were collected with a core sampler on the east coast of North Sulawesi in May 2014 and on the west coast in October 2015. A total of 149 species from 14 higher taxa was collected. The most species-rich groups were polychaetes(56 species, 26% of total individual numbers), decapods(20 species, 9% of total numbers) and amphipods(18 species, 35% of total numbers). Between-station variations within a transect displayed different patterns between the east coast and the west coast. On the east coast, there were marked variations in abundance between stations within a transect for the macrofauna and amphipod assemblages. Both taxa richness and abundance varied with station for the macrofauna and polychaete assemblages on the west coast, resulting from the heterogeneity of the substrate along a transect. One-way ANOSIM together with MDS ordination indicated that macrofaunal community structure in seagrasses differed significantly between the east coast and the west coast, corresponding with the division of seagrasses into two broad categories of habitats, i.e.,mangrove-seagrass-reef continuum and seagrass-reef continuum. Compared with other studies in tropical areas,the abundance and diversity of benthic macrofauna in the present study were moderate. The reason for the two markedly distinct macrofaunal communities might be attributed to multiple factors, including sediment pattern,seagrass structure and temporal changes.展开更多
Recent studies have highlighted the valuable role played by mangrove forests in carbon sequestration and storage.Although Indonesia accounts for a large proportion of global mangrove area, knowledge on the carbon stoc...Recent studies have highlighted the valuable role played by mangrove forests in carbon sequestration and storage.Although Indonesia accounts for a large proportion of global mangrove area, knowledge on the carbon stock and sources in the Indonesian mangrove is still limited. In this study, we quantified the ecosystem organic carbon(OC) stock and its spatial variation at an oceanic mangrove in Wori, North Sulawesi, Indonesia. The sources of soil OC were also investigated. The results showed that the mangrove soil had a substantial OC stock containing15.4 kg/m2(calculated by carbon) in the top 50 cm soil, and represented the majority of the ecosystem OC stock at the Wori mangrove. The mangrove biomass and ecosystem OC stock were 8.3 kg/m2and 23.7 kg/m2, respectively.There was no significantly difference in the soil OC stock among the stations with difference distances offshore,while the highest mangrove biomass OC stock was found at the seaward station. Isotope mixing calculations showed that the rich OC in mangrove soils was attributed to the accumulated autochthonous mangrove source while the suspended organic matter in tidal water and the mangrove-adjacent seagrass contributed less than 20%to the soil OC. The results further demonstrated the importances of the oceanic mangrove in carbon storage and the mangrove plants in contributing OC to their soils.展开更多
Objective: To investigate the antioxidant, antibacterial, antimalarial activities and cytotoxicity of the n-hexane, ethyl acetate, n-butanol, and aqueous fractions from a crude extract of Lobophytum sp.Methods: This o...Objective: To investigate the antioxidant, antibacterial, antimalarial activities and cytotoxicity of the n-hexane, ethyl acetate, n-butanol, and aqueous fractions from a crude extract of Lobophytum sp.Methods: This organism was collected from the Selayar Islands(South Sulawesi). The antioxidant activity was performed by the 1,1-diphenyl-2-picryl hydrazyl radical scavenging method. All fractions from the crude extract of Lobophytum sp. were examined for their cytotoxicity using the brine shrimp lethality bioassay and heme polymerization inhibitory activity assay for antimalarial activity.Results: It was found that the ethyl acetate, n-butanol and aqueous fractions exhibited heme polymerization inhibitory activity with IC_(50) values of 11.7, 14.3 and 12.0 mg/m L,respectively, while the n-butanol fraction showed moderate antioxidant activity and cytotoxicity with IC_(50) values of 150.00 and 92.74 mg/m L, respectively.Conclusions: This study provides information on antioxidant, antibacterial and antimalarial activities as well as the cytotoxicity of all fractions from the crude extract of Lobophytum sp. This is a new report of antimalarial substances derived from Lobophytum sp.展开更多
The stable isotope ratios of nitrogen(δ^(15)N) and carbon(δ^(13)C) were applied in this study to analyze sediment carbon sources and primary food sources of epifauna in an oceanic mangrove forest in tropical North S...The stable isotope ratios of nitrogen(δ^(15)N) and carbon(δ^(13)C) were applied in this study to analyze sediment carbon sources and primary food sources of epifauna in an oceanic mangrove forest in tropical North Sulawesi, Indonesia. Proportional contribution of mangrove-derived carbon to the food sources was compared among epifauna belonging to different feeding guilds. The sediment in the mangrove site with a depleted δ^(13)C signature(-28.02‰± 0.24‰) mainly consists of mangrove-derived carbon. Analysis using Bayesian stable isotope mixing model in the R program shows that mangrove-derived carbon can dominate the food sources of a majority of the epifauna(11 out of the total 18 species), especially 2 sesarmid crabs Parasesarma semperi and Sesarma sp., crab Epixanthus dentatus, and snails Terebralia sulcata and Optediceros breviculum, which belong to various feeding guilds. Mangrove-derived carbon has a proportional contribution to the food sources of fiddle crab Tubuca coarctata and 3 littorinid snails(Littoraria spp.) close to that of suspended particulate organic matter. Three planktophagous bivalve species(Anadara antiquata, Anadara sp. and Callista erycina) were found to mainly feed on seagrass-derived materials. Mean proportional contributions of mangrove-derived carbon to the food sources were 50.15%, 59.60%, 46.20% and 27.58% for the carnivorous, omnivorous, phytophagous and planktophagous groups, respectively. The results suggest that mangrove-derived carbon can directly(via grazing plant tissues) or indirectly(via deposit feedings) make an important contribution to the food sources of epifauna in the oceanic mangrove forest where the allochthonous input of organic carbon is low.展开更多
Water samples were collected in order to study the spatial variation of photosynthetic pigments and phytoplankton community composition in the Lembeh Strait(Indonesia) and the Kelantan River Estuary(Malaysia)during Ju...Water samples were collected in order to study the spatial variation of photosynthetic pigments and phytoplankton community composition in the Lembeh Strait(Indonesia) and the Kelantan River Estuary(Malaysia)during July and August 2016, respectively. Phytoplankton photosynthetic pigments were detected using high performance liquid chromatography combining with the CHEMTAX software to confirm the Chl a biomass and community composition. The Chl a concentration was low at surface in the Lembeh Strait, which it was 0.580–0.682 μg/L, with the average(0.620±0.039) μg/L. Nevertheless, the Chl a concentration fluctuated violently at surface in the Kelantan River Estuary, in which the biomass was 0.299–3.988 μg/L, with the average(0.922±0.992) μg/L. The biomass at bottom water was higher than at surface in the Kelantan River Estuary, in which the Chl a concentration was 0.704–2.352 μg/L, with the average(1.493±0.571) μg/L. Chl b, zeaxanthin and fucoxanthin were three most abundant pigments in the Lembeh Strait. As a consequence, phytoplankton community composition was different in the two study areas. In the Lembeh Strait, prasinophytes(26.48%±0.83%) and Synechococcus(25.73%±4.13%) occupied ~50% of the Chl a biomass, followed by diatoms(20.49%±2.34%) and haptophytes T8(15.13%±2.42%). At surface water in the Kelantan River Estuary, diatoms(58.53%±18.44%)dominated more than half of the phytoplankton biomass, followed by Synechococcus(27.27%±14.84%) and prasinophytes(7.00%±4.39%). It showed the similar status at the bottom water in the Kelantan River Estuary,where diatoms, Synechococcus and prasinophytes contributed 64.89%±15.29%, 16.23%±9.98% and 8.91%±2.62%,respectively. The different phytoplankton community composition between the two regions implied that the bottom up control affected the phytoplankton biomass in the Lembeh Strait where the oligotrophic water derived from the West Pacific Ocean. The terrigenous nutrients supplied the diatoms growing, and pico-phytoplankton was grazed through top down control in the Kelantan River Estuary.展开更多
Organisms of delta form unique ecosystem consist of organisms of endemic, ocean and transition waters. Both Porong and Solo Deltas of East Java have a unique morphological characteristic because they were formed by di...Organisms of delta form unique ecosystem consist of organisms of endemic, ocean and transition waters. Both Porong and Solo Deltas of East Java have a unique morphological characteristic because they were formed by different sediments. During the study on foraminifera in the two deltas, agglutinated foraminifera were given special attention since there were so few records on the occurrence of this group from Indonesia. Agglutinated foraminifera characterized by their shell (test) formed materials that consisting of attachment of foreign materials and cemented by CaCO3 and SiO3. This study was conducted on November 2007 and showed the relatively similar result on Porong and Solo Deltas in term of species. But the number of collected specimens is significantly different, which was recorded more than doubled. Of the 15 stations studied in each delta, 19 species were collected from the Porong Delta and 21 species were in all 15 stations of the Solo Delta. The stations which located close to the mouth of the river contain more number of individuals than that away from it, especially Ammobaculites agglutinans and Textularia pseudogramen. Generally, the number of collected agglutinated foraminifera of Porong Delta was more abundant than Solo Delta.展开更多
Based on oceanographic survey data in June 2012 in the Lembeh Strait, the zooplankton ecological characteristics such as species composition, individual abundance, dominant species and distribution were analyzed. The ...Based on oceanographic survey data in June 2012 in the Lembeh Strait, the zooplankton ecological characteristics such as species composition, individual abundance, dominant species and distribution were analyzed. The results showed that 183 species(including 4 sp.) had been recognized, most of them belonged to copepoda.Cnidaria followed with 43 species(including 1 sp.) were identified. The average abundance of zooplankton was(150.47±58.91) ind./m3. As to the horizontal distribution, the abundance of the zooplankton was higher in the southern waters than in the northern waters. The dominant species in the study area were Lensia subtiloides,Sagitta enflata, Lucifer intermedius, Oikopleura rufescens, Diphyes chamissoni, Creseis acicula, Subeucalanus subcrassus, Temora discaudata, Aglaura hemistoma, Doliolum denticulatum, Canthocalanus pauper, Oikopleura longicauda and Nanomia bijuga. Zooplankton biodiversity indexes were higher in study area than previous study in the other regions. The findings from this study provide important baseline information for future research and monitoring programs.展开更多
Two field observations were conducted around the Lembeh Strait in September 2015 and 2016, respectively.Evidences indicate that seawater around the Lembeh Strait is consisted of North Pacific Tropical Water(NPTW),Nort...Two field observations were conducted around the Lembeh Strait in September 2015 and 2016, respectively.Evidences indicate that seawater around the Lembeh Strait is consisted of North Pacific Tropical Water(NPTW),North Pacific Intermediate Water(NPIW), North Pacific Tropical Intermediate Water(NPTIW) and Antarctic Intermediate Water(AAIW). Around the Lembeh Strait, there exist some north-south differences in terms of water mass properties. NPTIW is only found in the southern Lembeh Strait. Water mass with the salinity of 34.6 is only detected at 200–240 m between NPTW and NPTIW in the southern Lembeh Strait, and results from the process of mixing between the saltier water transported from the South Pacific Ocean and the lighter water from the North Pacific Ocean and Sulawesi Sea. According to the analysis on mixing layer depth, it is indicated that there exists an onshore surface current in the northern Lembeh Strait and the surface current in the Lembeh Strait is southward.These dramatic differences of water masses demonstrate that the less water exchange has been occurred between the north and south of Lembeh Strait. In 2015, the positive wind stress curl covering the northern Lembeh Strait induces the shoaling of thermocline and deepening of NPIW, which show that the north-south difference of airsea system is possible of inducing north-south differences of seawater properties.展开更多
Suspended particulate matter(SPM) has been known as an important variable in the organic matter flow of coastal ecosystem. Half of burial carbon in seagrass meadows is contributed by allochthonous sources that compose...Suspended particulate matter(SPM) has been known as an important variable in the organic matter flow of coastal ecosystem. Half of burial carbon in seagrass meadows is contributed by allochthonous sources that compose the SPM such as phytoplankton, seagrass detritus, marine snow aggregates and terrestrially derived particles. Each composition of the SPM contributes different roles and is important to be identified, for instance,the exact contribution of seagrass detritus will be useful for determination of carbon export through the detritus form in seagrass meadows. Here, the SPM of seagrass meadows is studied in Bintan Island and the Selayar Archipelago. The aim of this research is to determine the source origin of the SPM using a stable isotope signature.In order to fulfill this aim, the objectives are defined as:(1) to specify the stable isotope signature(δ13C and δ15N)of the SPM, and(2) to determine the proportional distribution of the SPM's prospectus sources. The result shows that the possibility of the source origin of the SPM includes a seagrass fraction(Enhalus acoroides and Thalassia hemprichii), terrestrial C4 plant, macroalgae, and terrestrial C3 plant. The SPM lies between the marine-and terrigenous-end members. However, it seems that the SPM is more to be terrigenous-end and allochthonous.According to a Bayesian mixing model, the terrestrial C4 has the highest contribution of the SPM at all sites except Barugaia and Pasi Island in Selayar(i.e., the highest contribution of the SPM is from the detritus of E. acoroides).The second contribution has been contributed by either seagrass detritus(E. acoroides or Th. hemprichii) or terrestrial C3 plant. The finding of this study indicates that there is a strong influence of the terrigenous sources in the SPM of the seagrass meadows.展开更多
In terms of downward transport,suspended particulate matter(SPM)from marine or terrigenous sources is an essential contributor to the carbon cycle.Within mesoscale environments such as seagrass ecosystems,SPM flux is ...In terms of downward transport,suspended particulate matter(SPM)from marine or terrigenous sources is an essential contributor to the carbon cycle.Within mesoscale environments such as seagrass ecosystems,SPM flux is an essential part of the total carbon budget that is transported within the ecosystem.By assessing the total SPM transport from water column to sediment,potential carbon burial can be estimated.However,SPM may decompose or reforming aggregate during transport,so estimating the vertical flux without knowing the decomposition rate will lead to over-or underestimation of the total carbon budget.Here this paper presents the potential decomposition rate of the SPM in seagrass ecosystems in an attempt to elucidate the carbon dynamics of SPM.SPM was collected from the seagrass ecosystems located at Sikka and Sorong in Indonesia.In situ experiments using SPM traps were conducted to assess the vertical downward flux and decomposition rate of SPM.The isotopic profile of SPM was measured together with organic carbon and total nitrogen content.The results show that SPM was transported to the bottom of the seagrass ecosystem at a rate of up to(129.45±53.79)mg/(m^(2)·h)(according to carbon).Considering the whole period of inundation of seagrass meadows,SPM downward flux reached a maximum of 3096 mg/(m^(2)·d)(according to carbon).The decomposition rate was estimated at from 5.9μg/(mg·d)(according to carbon)to 26.6μg/(mg·d)(according to carbon).Considering the total downward flux of SPM in the study site,the maximum decomposed SPM was estimated 39.9 mg/(m^(2)·d)(according to carbon)and 82.6 mg/(m^(2)·d)(according to carbon)for study site at Sorong and Sikka,respectively.The decomposed SPM can be 0.6%–2.7%of the total SPM flux,indicating that it is a small proportion of the total flux.The seagrass ecosystems of Sorong and Sikka SPM show an autochthonous tendency with the primary composition of marine-end materials.展开更多
Mangrove ecosystems are sites with high biodiversity of benthic fauna, and fiddler crabs(genus Uca) are common benthic fauna in mangroves. The North Sulawesi in Indonesia has a good condition of mangrove while the inf...Mangrove ecosystems are sites with high biodiversity of benthic fauna, and fiddler crabs(genus Uca) are common benthic fauna in mangroves. The North Sulawesi in Indonesia has a good condition of mangrove while the information of the fiddler crabs is still limited. Manual samplings were conducted in wet, dry and transient seasons at a mangrove in Kema, North Sulawesi to investigate the species composition, density and distribution pattern of fiddler crabs. A total of 168 individuals, subjected to eight species of genus Uca crabs were collected at the mangrove, with U. triangularis having the highest abundance and U. annulipes having the lowest abundance.The densities of fiddle crabs were 27.56 ind./m2, 32.89 ind./m2and 14.22 ind./m2at the seaward, middle and landward zones, respectively, and the density was higher in dry and wet seasons than in transient season.展开更多
The community structure of zooplankton has been conducted in the Lembeh Strait in Bitung and Wori Beach in Manado, North Sulawesi in October 2015. Sampling of this research was conducted in 22 sampling sites along the...The community structure of zooplankton has been conducted in the Lembeh Strait in Bitung and Wori Beach in Manado, North Sulawesi in October 2015. Sampling of this research was conducted in 22 sampling sites along the strait. Zooplankton samples were collected from 22 stations, by NORPAC 300 μm net that was vertically hauled from maximum 10 m depth up to the surface water. The samples were poured into the bottle with formalin of 4%as preservative. The results showed that there were 43 taxa of zooplankton. The abundance of zooplankton was between 21.216–4 193.776 ind./m;. The dominant taxa were copepod, especially Calanoida. The composition of zooplankton was relatively similar in all stations. We showed the abundance, dominance, composition and distribution of zooplankton at this research. More extensive studies concerning zooplankton is required to understand zooplankton biodiversity as a whole especially on the geographical and spatial distribution to describe population and community dynamic in the Lembeh Strait and Wori Beach.展开更多
Three specimens of the serranid fish(Serranidae), Plectranthias kamii Randall, 1980 were collected from fish market, Bitung, North Sulawesi on May and June 2010. Some morphological characters P. kamii is closely relat...Three specimens of the serranid fish(Serranidae), Plectranthias kamii Randall, 1980 were collected from fish market, Bitung, North Sulawesi on May and June 2010. Some morphological characters P. kamii is closely related to P. sheni, P. megalophthalmus, P. retrofasciatus, P. rubrifasciatus, P. knappi, P. helenae, P. pelicieri, P. jothyi, P.retrofasciatus and P. randalli in sharing of body width, upper jaw length, pelvic spine length and orbit diameter.Meristic count characters of P. kamii differ from P. sheni, P. pilicieri, P. megalophthalmus, P. retrofasciatus and P.rubrifasciatus in having more numerous dorsal spine(18 vs. 15–17) and below lateral line(33–34 vs. 29–33) and differ from P. megalophthalmus and P. rubrifasciatus in having more numerous pored scales in lateral line(13 vs.14–15) and shorter of anal spine. The present anthiine fish collected from Bitung, Indonesia was described as new record and bringing the total number of species of this genus known in Indonesia to seven.展开更多
Phytoplankton species composition and abundance in the Lembeh Strait waters was studied in four cruises of April 2013, May 2014, June 2012 and October 2015, during the period of monsoon transition time of SE monsoon.W...Phytoplankton species composition and abundance in the Lembeh Strait waters was studied in four cruises of April 2013, May 2014, June 2012 and October 2015, during the period of monsoon transition time of SE monsoon.With data obtained the seasonal alternations of phytoplankton community structures and its driving factors were discussed. A total of 416 taxa belonging to 5 classes of phytoplankton were recorded in the four month surveys.Phytoplankton density was averaged 2 348 cell/L and diatoms and dinoflagellates had the most diversified species. Cyanobacterium was characterized by its low species numbers but high abundance in the waters of Lembeh Strait. Total phytoplankton abundance occurred low in April and October in the monsoon transition period and it raised high in May and June during the SE monsoon. Frequently occurred species were pelagic diatoms in addition to cyanobacterium Trichodesmium. Abundance and diversity of phytoplankton significantly differed seasonally. The diatoms Thalassionema and Pseudo-nitzschia, and cyanobacterium Trichodesmium contributed most to the community dissimilarities. Due to potentially higher nutrient supply in the south of Lembeh Strait, diatoms and dinoflagellates showed higher densities in the south than in the north of the strait.Though, cyanobacterium preferred distributing much evenly in all waters, it had higher density in the southern Lembeh Strait. Total phytoplankton abundance is quite low compared with the Jakarta Bay and some bays in China. Analysis showed that nutrients from upwelling forced by SE monsoon are the key factor varying the monthly phytoplankton abundances. Due to its primitive nature state, Lembeh water can be an ideal location for the study of pelagic ecosystem under merely the influence of macro environment changes with lower background noise from human activities.展开更多
Fish species composition and spatio-temporal variability of the community were studied in a tropical seagrass meadow located in a lagoon in the eastern part of North Sulawesi. The diversity of fish community in the se...Fish species composition and spatio-temporal variability of the community were studied in a tropical seagrass meadow located in a lagoon in the eastern part of North Sulawesi. The diversity of fish community in the seagrass meadows was relatively high, with the Shannon-Wiener index ranging from 1.57 to 3.69. The family Apogonidae was the most dominant in abundance(8.27 ind./(100 m2)) and biomass(28.49 g/(100 m2)). At the species level,Apogon lateralis and Sphaeramia orbicularis were the most dominant species in abundance and biomass,respectively. For spatial distribution on species, the end, middle and mouth of the lagoon clustered together as a whole, which may be due to the substrate types found in those zones. The fish species, fish abundance and fish biomass were greater in the dry and wet seasons than in the transition season, which is explained by the strong monsoon, which provides a more suitable environment and food for the fish. The maximum length of 93.10% of the captured species was less than their length at maturity, indicating that seagrass meadows are nursery habitats for many fishes. Therefore, protection of the seagrass meadows is essential for fisheries and sustainable resource utilization.展开更多
Bacterial diseases affecting corals pose an enormous threat to the health of coral reefs. The relationship between certain bacterial species and coral diseases remain largely unknown. Pigment abnormalities are common ...Bacterial diseases affecting corals pose an enormous threat to the health of coral reefs. The relationship between certain bacterial species and coral diseases remain largely unknown. Pigment abnormalities are common in Porites lutea. Here we used Illumina 16S rRNA gene sequencing to analyze the bacterial communities associated with healthy P. lutea and P. lutea with pigment abnormalities. We observed an increase of alpha diversity of the bacterial community of P. lutea with pigment abnormalities, relative to healthy corals. We then identified changes in the abundance of individual operational taxonomic units(OTUs) between pigmented and healthy corals. We were able to identify eight OTUs associated with pigment abnormalities, which are possibly the causative agents of pigment abnormalities.展开更多
Anthropogenic impacts and natural disturbances have been intense recently in the global scale, affecting the composition of coral reef benthic communities from coral to algal dominated reefs. However, this condition d...Anthropogenic impacts and natural disturbances have been intense recently in the global scale, affecting the composition of coral reef benthic communities from coral to algal dominated reefs. However, this condition does not always occur considering corals are able to recover when the stressors falter. This study aims to investigate the change in coral reef benthic communities and the relationship among benthic categories. The study was carried out in 2014 and 2016 at five sites, three sites in the Lembeh Strait and two sites in Likupang, North Sulawesi Province. Underwater Photo Transect(UPT) was used at depth of around 4–6 m in slope areas. The result indicated that the benthic communities were slightly changing: the percent covers of hard corals, sponges, soft corals, macroalgae and substrate categories were not significantly different between the years but category of others, particularly seasonally growing hydroid, increased significantly, occupying the available substrates and overtopping other benthos surrounding. The study also found that there was a significant relationship between the change in benthic gradient and the number of hard coral colonies: when the composition becomes less complex, the number of colony declines. In contrast, the hard coral diversity remained unchanged, suggesting the coral reefs apparently have an ecological resilience(sustainable species diversity) against the change although ecological complexity declines. In addition, the hard coral cover was significantly correlated with soft coral and sponge covers, which did not change significantly among the years. In general, the coral reefs in North Sulawesi might experience a temporary blip due to the increasing percent cover of others, and be predicted to recover as there was no indication of soft corals and sponges to increase significantly. However, it is necessary to investigate the dynamic of benthic communities in different depth gradients to gain a comprehensive understanding as the communities respond differently to the light intensity.展开更多
Due to the elevated atmospheric carbon dioxide, ocean acidification(OA) has recently emerged as a research theme in marine biology due to an expected deleterious effect of altered seawater chemistry on calcification. ...Due to the elevated atmospheric carbon dioxide, ocean acidification(OA) has recently emerged as a research theme in marine biology due to an expected deleterious effect of altered seawater chemistry on calcification. A system simulating future OA scenario is crucial for OA-related studies. Here, we designed an OA-simulated system(OASys) with three solenoid-controlled CO_2 gas channels. The OASys can adjust the pH of the seawater by bubbling CO_2 gas into seawaters via feedback systems. The OASys is very simple in structure with an integrated design and is new-user friendly with the instruction. Moreover, the OASys can monitor and record real-time pH values and can maintain pH levels within 0.02 pH unit. In a 15-d experiment, the OASys was applied to simulate OA in which the expected target pH values were 8.00, 7.80 and 7.60 to study the calcifying response of Galaxea fascicularis. The results showed daily mean seawater pH values held at pH 8.00±0.01, 7.80±0.01 and 7.61±0.01 over15 d. Correspondingly, the coral calcification of G. fascicularis gradually decreased with reduced pH.展开更多
Objective:To study the distribution and diversity of species and isolated molecules,according to their structure classes,from Indonesian marine organisms.Methods:This study was performed by using the SciFinder^(®...Objective:To study the distribution and diversity of species and isolated molecules,according to their structure classes,from Indonesian marine organisms.Methods:This study was performed by using the SciFinder^(®)database,MarinLit and references from relevant articles from 1980 to 2014 which collected all the scientific publications dealing with the isolation of chemical compounds from Indonesian marine macroorganisms and microorganisms.Results:The discovery of novel compounds from Indonesian marine organisms gave us a result of a total of 78 papers.Alkaloids,terpenoids and peptides(84,67 and 15 new compounds,respectively)represented the three main chemical classes of compounds discovered from Indonesian marine organisms,and together with the other chemical classes showed a range of biological activities.Conclusions:The new marine compounds are mainly from sponges and soft corals.Alkaloids,terpenoids and peptides are the most prolific compounds isolated from Indonesian marine organisms.Most marine natural products from Indonesian organisms have been screened for anticancer or cytotoxicity activities.展开更多
Objective:To find a potent antibiotic producer from the sponge-associated bacteria as well as to profile the important substances.Methods:Sponge collection,bacteria isolation,extraction and characterization of potent ...Objective:To find a potent antibiotic producer from the sponge-associated bacteria as well as to profile the important substances.Methods:Sponge collection,bacteria isolation,extraction and characterization of potent active compounds were carried out for this study.Results:Approximately 59 single strains of bacteria were isolated from this sponge.Totally 40 strains showed activity against Escerichia coli,Staphylococcus aureus and Vibrio eltor.The chemical separation of the potent strain Bacterium sp.Lb.10%.2.1.1.b,using n-phase column chromatography revealed 7 active fractions(7,8,9,10,11,14 and 15).The gas chromatography-mass spectrometer analysis of Fraction 7 indicated some phenolic compounds including 4-nonylphenol,methyl 3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate,acetosyringone,2,4-bis(1-phenylethyl)phenol,1,2-benzenedicarboxylic acid,mono(2-ethylhexyl)ester,tri(2-ethylhexyl)trimellitate and oleamide.Conclusions:Indeed,this is a preliminary information in profiling chemical substances,produced by Bacterium sp.Lb.10%.2.1.1.b.Further purification and structural chemical determination were needed to find a comprehensive result.展开更多
基金China-Indonesia Maritime Cooperation Fund Project“China-Indonesia Bitung Joint Marine Ecological Station Establishment”the Scientific Research Foundation of Third Institute of Oceanography,SOA under contract No.2011034
文摘Seagrasses are one of the most productive ecosystems in coastal areas and support a wide variety of associated fauna. The tropical Indo-Pacific region is considered to have the highest diversity of seagrass plant species and the largest distribution areas of seagrass, yet the seagrass macrofauna in this region are poorly understood. To help fill this gap in our knowledge, an ecological survey was conducted to describe the abundance and diversity of benthic macrofauna from tropical seagrass beds and to determine between-station variations within a transect and between-site variations in macrofaunal abundance, taxa richness and community structure. Benthic macrofaunal samples associated with seagrass beds were collected with a core sampler on the east coast of North Sulawesi in May 2014 and on the west coast in October 2015. A total of 149 species from 14 higher taxa was collected. The most species-rich groups were polychaetes(56 species, 26% of total individual numbers), decapods(20 species, 9% of total numbers) and amphipods(18 species, 35% of total numbers). Between-station variations within a transect displayed different patterns between the east coast and the west coast. On the east coast, there were marked variations in abundance between stations within a transect for the macrofauna and amphipod assemblages. Both taxa richness and abundance varied with station for the macrofauna and polychaete assemblages on the west coast, resulting from the heterogeneity of the substrate along a transect. One-way ANOSIM together with MDS ordination indicated that macrofaunal community structure in seagrasses differed significantly between the east coast and the west coast, corresponding with the division of seagrasses into two broad categories of habitats, i.e.,mangrove-seagrass-reef continuum and seagrass-reef continuum. Compared with other studies in tropical areas,the abundance and diversity of benthic macrofauna in the present study were moderate. The reason for the two markedly distinct macrofaunal communities might be attributed to multiple factors, including sediment pattern,seagrass structure and temporal changes.
基金The China-Indonesia Ecological Station Establishment and Marine Biodiversity Investigation in North Sulawesi Seathe Development and Implement Ocean Strategic Planning and Policy supported by Ministry of Natural Resources,PRCthe National Natural Science Foundation of China under contract Nos 41606105 and 41776102
文摘Recent studies have highlighted the valuable role played by mangrove forests in carbon sequestration and storage.Although Indonesia accounts for a large proportion of global mangrove area, knowledge on the carbon stock and sources in the Indonesian mangrove is still limited. In this study, we quantified the ecosystem organic carbon(OC) stock and its spatial variation at an oceanic mangrove in Wori, North Sulawesi, Indonesia. The sources of soil OC were also investigated. The results showed that the mangrove soil had a substantial OC stock containing15.4 kg/m2(calculated by carbon) in the top 50 cm soil, and represented the majority of the ecosystem OC stock at the Wori mangrove. The mangrove biomass and ecosystem OC stock were 8.3 kg/m2and 23.7 kg/m2, respectively.There was no significantly difference in the soil OC stock among the stations with difference distances offshore,while the highest mangrove biomass OC stock was found at the seaward station. Isotope mixing calculations showed that the rich OC in mangrove soils was attributed to the accumulated autochthonous mangrove source while the suspended organic matter in tidal water and the mangrove-adjacent seagrass contributed less than 20%to the soil OC. The results further demonstrated the importances of the oceanic mangrove in carbon storage and the mangrove plants in contributing OC to their soils.
基金Supported by the Coral Reef Rehabilitation and Management Program–Coral Triangle Initiative(Grant No.COREMAP CTI-LIPI 2016 No.10876401/ADB LOAN No.3094-INO)
文摘Objective: To investigate the antioxidant, antibacterial, antimalarial activities and cytotoxicity of the n-hexane, ethyl acetate, n-butanol, and aqueous fractions from a crude extract of Lobophytum sp.Methods: This organism was collected from the Selayar Islands(South Sulawesi). The antioxidant activity was performed by the 1,1-diphenyl-2-picryl hydrazyl radical scavenging method. All fractions from the crude extract of Lobophytum sp. were examined for their cytotoxicity using the brine shrimp lethality bioassay and heme polymerization inhibitory activity assay for antimalarial activity.Results: It was found that the ethyl acetate, n-butanol and aqueous fractions exhibited heme polymerization inhibitory activity with IC_(50) values of 11.7, 14.3 and 12.0 mg/m L,respectively, while the n-butanol fraction showed moderate antioxidant activity and cytotoxicity with IC_(50) values of 150.00 and 92.74 mg/m L, respectively.Conclusions: This study provides information on antioxidant, antibacterial and antimalarial activities as well as the cytotoxicity of all fractions from the crude extract of Lobophytum sp. This is a new report of antimalarial substances derived from Lobophytum sp.
基金supported by the National Key Technologies Research and Development Program of China (No. 2017YFC0506101)the China-ASEAN Maritime Fund ‘Monitoring and Conservation of the Coastal Ecosystems in the South China Sea’the National Natural Science Foundation of China (No. 31101876)。
文摘The stable isotope ratios of nitrogen(δ^(15)N) and carbon(δ^(13)C) were applied in this study to analyze sediment carbon sources and primary food sources of epifauna in an oceanic mangrove forest in tropical North Sulawesi, Indonesia. Proportional contribution of mangrove-derived carbon to the food sources was compared among epifauna belonging to different feeding guilds. The sediment in the mangrove site with a depleted δ^(13)C signature(-28.02‰± 0.24‰) mainly consists of mangrove-derived carbon. Analysis using Bayesian stable isotope mixing model in the R program shows that mangrove-derived carbon can dominate the food sources of a majority of the epifauna(11 out of the total 18 species), especially 2 sesarmid crabs Parasesarma semperi and Sesarma sp., crab Epixanthus dentatus, and snails Terebralia sulcata and Optediceros breviculum, which belong to various feeding guilds. Mangrove-derived carbon has a proportional contribution to the food sources of fiddle crab Tubuca coarctata and 3 littorinid snails(Littoraria spp.) close to that of suspended particulate organic matter. Three planktophagous bivalve species(Anadara antiquata, Anadara sp. and Callista erycina) were found to mainly feed on seagrass-derived materials. Mean proportional contributions of mangrove-derived carbon to the food sources were 50.15%, 59.60%, 46.20% and 27.58% for the carnivorous, omnivorous, phytophagous and planktophagous groups, respectively. The results suggest that mangrove-derived carbon can directly(via grazing plant tissues) or indirectly(via deposit feedings) make an important contribution to the food sources of epifauna in the oceanic mangrove forest where the allochthonous input of organic carbon is low.
基金The National Key R&D Program of China under contract Nos 2017YFC0604902 and 2017YFC1405101the ChinaIndonesia Maritime Cooperation Fund Project "China-Indonesia Bitung Ecological Station Establishment"the China-ASEAN Maritime Cooperation Fund and HICoE-MOHE Grant IOES–2014
文摘Water samples were collected in order to study the spatial variation of photosynthetic pigments and phytoplankton community composition in the Lembeh Strait(Indonesia) and the Kelantan River Estuary(Malaysia)during July and August 2016, respectively. Phytoplankton photosynthetic pigments were detected using high performance liquid chromatography combining with the CHEMTAX software to confirm the Chl a biomass and community composition. The Chl a concentration was low at surface in the Lembeh Strait, which it was 0.580–0.682 μg/L, with the average(0.620±0.039) μg/L. Nevertheless, the Chl a concentration fluctuated violently at surface in the Kelantan River Estuary, in which the biomass was 0.299–3.988 μg/L, with the average(0.922±0.992) μg/L. The biomass at bottom water was higher than at surface in the Kelantan River Estuary, in which the Chl a concentration was 0.704–2.352 μg/L, with the average(1.493±0.571) μg/L. Chl b, zeaxanthin and fucoxanthin were three most abundant pigments in the Lembeh Strait. As a consequence, phytoplankton community composition was different in the two study areas. In the Lembeh Strait, prasinophytes(26.48%±0.83%) and Synechococcus(25.73%±4.13%) occupied ~50% of the Chl a biomass, followed by diatoms(20.49%±2.34%) and haptophytes T8(15.13%±2.42%). At surface water in the Kelantan River Estuary, diatoms(58.53%±18.44%)dominated more than half of the phytoplankton biomass, followed by Synechococcus(27.27%±14.84%) and prasinophytes(7.00%±4.39%). It showed the similar status at the bottom water in the Kelantan River Estuary,where diatoms, Synechococcus and prasinophytes contributed 64.89%±15.29%, 16.23%±9.98% and 8.91%±2.62%,respectively. The different phytoplankton community composition between the two regions implied that the bottom up control affected the phytoplankton biomass in the Lembeh Strait where the oligotrophic water derived from the West Pacific Ocean. The terrigenous nutrients supplied the diatoms growing, and pico-phytoplankton was grazed through top down control in the Kelantan River Estuary.
文摘Organisms of delta form unique ecosystem consist of organisms of endemic, ocean and transition waters. Both Porong and Solo Deltas of East Java have a unique morphological characteristic because they were formed by different sediments. During the study on foraminifera in the two deltas, agglutinated foraminifera were given special attention since there were so few records on the occurrence of this group from Indonesia. Agglutinated foraminifera characterized by their shell (test) formed materials that consisting of attachment of foreign materials and cemented by CaCO3 and SiO3. This study was conducted on November 2007 and showed the relatively similar result on Porong and Solo Deltas in term of species. But the number of collected specimens is significantly different, which was recorded more than doubled. Of the 15 stations studied in each delta, 19 species were collected from the Porong Delta and 21 species were in all 15 stations of the Solo Delta. The stations which located close to the mouth of the river contain more number of individuals than that away from it, especially Ammobaculites agglutinans and Textularia pseudogramen. Generally, the number of collected agglutinated foraminifera of Porong Delta was more abundant than Solo Delta.
基金The China-Indonesia Maritime Cooperation Fund Project "China-Indonesia Bitung Ecological Station Establishment"the National Natural Science Foundation of China under contract No.41306204+1 种基金the Scientific Research Foundation of Third Institute of Oceanography,SOA under contract Nos 2017010,2015012 and 2016012the National Special Project on Gas Hydrate under contract No.GZH201100311
文摘Based on oceanographic survey data in June 2012 in the Lembeh Strait, the zooplankton ecological characteristics such as species composition, individual abundance, dominant species and distribution were analyzed. The results showed that 183 species(including 4 sp.) had been recognized, most of them belonged to copepoda.Cnidaria followed with 43 species(including 1 sp.) were identified. The average abundance of zooplankton was(150.47±58.91) ind./m3. As to the horizontal distribution, the abundance of the zooplankton was higher in the southern waters than in the northern waters. The dominant species in the study area were Lensia subtiloides,Sagitta enflata, Lucifer intermedius, Oikopleura rufescens, Diphyes chamissoni, Creseis acicula, Subeucalanus subcrassus, Temora discaudata, Aglaura hemistoma, Doliolum denticulatum, Canthocalanus pauper, Oikopleura longicauda and Nanomia bijuga. Zooplankton biodiversity indexes were higher in study area than previous study in the other regions. The findings from this study provide important baseline information for future research and monitoring programs.
基金The National Key R&D Program of China under contract No.2017YFC1405101the Scientific Research Foundation of the Third Institute of Oceanography under contract No.2016025the China-Indonesia Maritime Cooperation Fund Project"ChinaIndonesia Bitung Ecological Station Establishment"
文摘Two field observations were conducted around the Lembeh Strait in September 2015 and 2016, respectively.Evidences indicate that seawater around the Lembeh Strait is consisted of North Pacific Tropical Water(NPTW),North Pacific Intermediate Water(NPIW), North Pacific Tropical Intermediate Water(NPTIW) and Antarctic Intermediate Water(AAIW). Around the Lembeh Strait, there exist some north-south differences in terms of water mass properties. NPTIW is only found in the southern Lembeh Strait. Water mass with the salinity of 34.6 is only detected at 200–240 m between NPTW and NPTIW in the southern Lembeh Strait, and results from the process of mixing between the saltier water transported from the South Pacific Ocean and the lighter water from the North Pacific Ocean and Sulawesi Sea. According to the analysis on mixing layer depth, it is indicated that there exists an onshore surface current in the northern Lembeh Strait and the surface current in the Lembeh Strait is southward.These dramatic differences of water masses demonstrate that the less water exchange has been occurred between the north and south of Lembeh Strait. In 2015, the positive wind stress curl covering the northern Lembeh Strait induces the shoaling of thermocline and deepening of NPIW, which show that the north-south difference of airsea system is possible of inducing north-south differences of seawater properties.
基金The Core Competence Research Project 2014the Research Agenda COREMAP-CTI 2015-2016the "Unggulan LIPI" Research Project 2017
文摘Suspended particulate matter(SPM) has been known as an important variable in the organic matter flow of coastal ecosystem. Half of burial carbon in seagrass meadows is contributed by allochthonous sources that compose the SPM such as phytoplankton, seagrass detritus, marine snow aggregates and terrestrially derived particles. Each composition of the SPM contributes different roles and is important to be identified, for instance,the exact contribution of seagrass detritus will be useful for determination of carbon export through the detritus form in seagrass meadows. Here, the SPM of seagrass meadows is studied in Bintan Island and the Selayar Archipelago. The aim of this research is to determine the source origin of the SPM using a stable isotope signature.In order to fulfill this aim, the objectives are defined as:(1) to specify the stable isotope signature(δ13C and δ15N)of the SPM, and(2) to determine the proportional distribution of the SPM's prospectus sources. The result shows that the possibility of the source origin of the SPM includes a seagrass fraction(Enhalus acoroides and Thalassia hemprichii), terrestrial C4 plant, macroalgae, and terrestrial C3 plant. The SPM lies between the marine-and terrigenous-end members. However, it seems that the SPM is more to be terrigenous-end and allochthonous.According to a Bayesian mixing model, the terrestrial C4 has the highest contribution of the SPM at all sites except Barugaia and Pasi Island in Selayar(i.e., the highest contribution of the SPM is from the detritus of E. acoroides).The second contribution has been contributed by either seagrass detritus(E. acoroides or Th. hemprichii) or terrestrial C3 plant. The finding of this study indicates that there is a strong influence of the terrigenous sources in the SPM of the seagrass meadows.
基金The LIPI-JSPS Joint Research Project 2019–2022 Research Grant under contract No.JPJSBP120198201the INSINAS Research Project 2020–2021 under contract No.10/INS/PPK/E4/2021。
文摘In terms of downward transport,suspended particulate matter(SPM)from marine or terrigenous sources is an essential contributor to the carbon cycle.Within mesoscale environments such as seagrass ecosystems,SPM flux is an essential part of the total carbon budget that is transported within the ecosystem.By assessing the total SPM transport from water column to sediment,potential carbon burial can be estimated.However,SPM may decompose or reforming aggregate during transport,so estimating the vertical flux without knowing the decomposition rate will lead to over-or underestimation of the total carbon budget.Here this paper presents the potential decomposition rate of the SPM in seagrass ecosystems in an attempt to elucidate the carbon dynamics of SPM.SPM was collected from the seagrass ecosystems located at Sikka and Sorong in Indonesia.In situ experiments using SPM traps were conducted to assess the vertical downward flux and decomposition rate of SPM.The isotopic profile of SPM was measured together with organic carbon and total nitrogen content.The results show that SPM was transported to the bottom of the seagrass ecosystem at a rate of up to(129.45±53.79)mg/(m^(2)·h)(according to carbon).Considering the whole period of inundation of seagrass meadows,SPM downward flux reached a maximum of 3096 mg/(m^(2)·d)(according to carbon).The decomposition rate was estimated at from 5.9μg/(mg·d)(according to carbon)to 26.6μg/(mg·d)(according to carbon).Considering the total downward flux of SPM in the study site,the maximum decomposed SPM was estimated 39.9 mg/(m^(2)·d)(according to carbon)and 82.6 mg/(m^(2)·d)(according to carbon)for study site at Sorong and Sikka,respectively.The decomposed SPM can be 0.6%–2.7%of the total SPM flux,indicating that it is a small proportion of the total flux.The seagrass ecosystems of Sorong and Sikka SPM show an autochthonous tendency with the primary composition of marine-end materials.
基金The China-Indonesia Ecological Station Establishment and Marine Biodiversity Investigation in North Sulawesi Seathe China-ASEAN Marine Protected Area Ecosystem Management Networkthe Public Science and Technology Research Funds Projects of Ocean under contract No.201505009
文摘Mangrove ecosystems are sites with high biodiversity of benthic fauna, and fiddler crabs(genus Uca) are common benthic fauna in mangroves. The North Sulawesi in Indonesia has a good condition of mangrove while the information of the fiddler crabs is still limited. Manual samplings were conducted in wet, dry and transient seasons at a mangrove in Kema, North Sulawesi to investigate the species composition, density and distribution pattern of fiddler crabs. A total of 168 individuals, subjected to eight species of genus Uca crabs were collected at the mangrove, with U. triangularis having the highest abundance and U. annulipes having the lowest abundance.The densities of fiddle crabs were 27.56 ind./m2, 32.89 ind./m2and 14.22 ind./m2at the seaward, middle and landward zones, respectively, and the density was higher in dry and wet seasons than in transient season.
基金The China-Indonesia Maritime Cooperation Fund Project"China-Indonesia Bitung Ecological Station Establishment"
文摘The community structure of zooplankton has been conducted in the Lembeh Strait in Bitung and Wori Beach in Manado, North Sulawesi in October 2015. Sampling of this research was conducted in 22 sampling sites along the strait. Zooplankton samples were collected from 22 stations, by NORPAC 300 μm net that was vertically hauled from maximum 10 m depth up to the surface water. The samples were poured into the bottle with formalin of 4%as preservative. The results showed that there were 43 taxa of zooplankton. The abundance of zooplankton was between 21.216–4 193.776 ind./m;. The dominant taxa were copepod, especially Calanoida. The composition of zooplankton was relatively similar in all stations. We showed the abundance, dominance, composition and distribution of zooplankton at this research. More extensive studies concerning zooplankton is required to understand zooplankton biodiversity as a whole especially on the geographical and spatial distribution to describe population and community dynamic in the Lembeh Strait and Wori Beach.
基金The Biodiversity Program of Kema and Amurang,Bitung Marine Life Conservation,Research Center for Oceanography,Indonesian Institute of Sciences,Indonesiathe China-Indonesia Maritime Cooperation Fund Project "ChinaIndonesia Bitung Ecological Station Establishment"
文摘Three specimens of the serranid fish(Serranidae), Plectranthias kamii Randall, 1980 were collected from fish market, Bitung, North Sulawesi on May and June 2010. Some morphological characters P. kamii is closely related to P. sheni, P. megalophthalmus, P. retrofasciatus, P. rubrifasciatus, P. knappi, P. helenae, P. pelicieri, P. jothyi, P.retrofasciatus and P. randalli in sharing of body width, upper jaw length, pelvic spine length and orbit diameter.Meristic count characters of P. kamii differ from P. sheni, P. pilicieri, P. megalophthalmus, P. retrofasciatus and P.rubrifasciatus in having more numerous dorsal spine(18 vs. 15–17) and below lateral line(33–34 vs. 29–33) and differ from P. megalophthalmus and P. rubrifasciatus in having more numerous pored scales in lateral line(13 vs.14–15) and shorter of anal spine. The present anthiine fish collected from Bitung, Indonesia was described as new record and bringing the total number of species of this genus known in Indonesia to seven.
基金The China-Indonesia Maritime Cooperation Fund Project "China-Indonesia Bitung Ecological Station Establishment"
文摘Phytoplankton species composition and abundance in the Lembeh Strait waters was studied in four cruises of April 2013, May 2014, June 2012 and October 2015, during the period of monsoon transition time of SE monsoon.With data obtained the seasonal alternations of phytoplankton community structures and its driving factors were discussed. A total of 416 taxa belonging to 5 classes of phytoplankton were recorded in the four month surveys.Phytoplankton density was averaged 2 348 cell/L and diatoms and dinoflagellates had the most diversified species. Cyanobacterium was characterized by its low species numbers but high abundance in the waters of Lembeh Strait. Total phytoplankton abundance occurred low in April and October in the monsoon transition period and it raised high in May and June during the SE monsoon. Frequently occurred species were pelagic diatoms in addition to cyanobacterium Trichodesmium. Abundance and diversity of phytoplankton significantly differed seasonally. The diatoms Thalassionema and Pseudo-nitzschia, and cyanobacterium Trichodesmium contributed most to the community dissimilarities. Due to potentially higher nutrient supply in the south of Lembeh Strait, diatoms and dinoflagellates showed higher densities in the south than in the north of the strait.Though, cyanobacterium preferred distributing much evenly in all waters, it had higher density in the southern Lembeh Strait. Total phytoplankton abundance is quite low compared with the Jakarta Bay and some bays in China. Analysis showed that nutrients from upwelling forced by SE monsoon are the key factor varying the monthly phytoplankton abundances. Due to its primitive nature state, Lembeh water can be an ideal location for the study of pelagic ecosystem under merely the influence of macro environment changes with lower background noise from human activities.
基金The China-Indonesia Maritime Cooperation Fund Project "China-Indonesia Bitung Ecological Station Establishment"the National Natural Science Foundation of China under contract Nos 41676096 and 41506123+3 种基金the Biodiversity of Coastal Ecosystem,Kema,North Sulawesithe Scientific Research Foundation of Third Institute of Oceanography,SOA under contract No.2015024the National Key Research and Development Program of China under contract Nos 2017YFC1405101 and2017YFC0506105the Public Science and Technology Research Funds Projects of Ocean under contract No.201505009
文摘Fish species composition and spatio-temporal variability of the community were studied in a tropical seagrass meadow located in a lagoon in the eastern part of North Sulawesi. The diversity of fish community in the seagrass meadows was relatively high, with the Shannon-Wiener index ranging from 1.57 to 3.69. The family Apogonidae was the most dominant in abundance(8.27 ind./(100 m2)) and biomass(28.49 g/(100 m2)). At the species level,Apogon lateralis and Sphaeramia orbicularis were the most dominant species in abundance and biomass,respectively. For spatial distribution on species, the end, middle and mouth of the lagoon clustered together as a whole, which may be due to the substrate types found in those zones. The fish species, fish abundance and fish biomass were greater in the dry and wet seasons than in the transition season, which is explained by the strong monsoon, which provides a more suitable environment and food for the fish. The maximum length of 93.10% of the captured species was less than their length at maturity, indicating that seagrass meadows are nursery habitats for many fishes. Therefore, protection of the seagrass meadows is essential for fisheries and sustainable resource utilization.
基金The China-Indonesia Maritime Cooperation Fund Project "China-Indonesia Bitung Ecological Station Establishment"the National Natural Science Foundation of China under contract No.41506180the Public Science and Technology Research Funds Projects of Ocean under contract No.201505009
文摘Bacterial diseases affecting corals pose an enormous threat to the health of coral reefs. The relationship between certain bacterial species and coral diseases remain largely unknown. Pigment abnormalities are common in Porites lutea. Here we used Illumina 16S rRNA gene sequencing to analyze the bacterial communities associated with healthy P. lutea and P. lutea with pigment abnormalities. We observed an increase of alpha diversity of the bacterial community of P. lutea with pigment abnormalities, relative to healthy corals. We then identified changes in the abundance of individual operational taxonomic units(OTUs) between pigmented and healthy corals. We were able to identify eight OTUs associated with pigment abnormalities, which are possibly the causative agents of pigment abnormalities.
基金The China-Indonesia Maritime Cooperation Fund Project "China-Indonesia Bitung Ecological Station Establishment"the National Natural Science Foundation of China under contract No.41676096+1 种基金the Biodiversity of Coastal Ecosystem,Kema,North Sulawesithe Scientific Research Foundation of Third Institute of Oceanography,SOA under contract No.2015024
文摘Anthropogenic impacts and natural disturbances have been intense recently in the global scale, affecting the composition of coral reef benthic communities from coral to algal dominated reefs. However, this condition does not always occur considering corals are able to recover when the stressors falter. This study aims to investigate the change in coral reef benthic communities and the relationship among benthic categories. The study was carried out in 2014 and 2016 at five sites, three sites in the Lembeh Strait and two sites in Likupang, North Sulawesi Province. Underwater Photo Transect(UPT) was used at depth of around 4–6 m in slope areas. The result indicated that the benthic communities were slightly changing: the percent covers of hard corals, sponges, soft corals, macroalgae and substrate categories were not significantly different between the years but category of others, particularly seasonally growing hydroid, increased significantly, occupying the available substrates and overtopping other benthos surrounding. The study also found that there was a significant relationship between the change in benthic gradient and the number of hard coral colonies: when the composition becomes less complex, the number of colony declines. In contrast, the hard coral diversity remained unchanged, suggesting the coral reefs apparently have an ecological resilience(sustainable species diversity) against the change although ecological complexity declines. In addition, the hard coral cover was significantly correlated with soft coral and sponge covers, which did not change significantly among the years. In general, the coral reefs in North Sulawesi might experience a temporary blip due to the increasing percent cover of others, and be predicted to recover as there was no indication of soft corals and sponges to increase significantly. However, it is necessary to investigate the dynamic of benthic communities in different depth gradients to gain a comprehensive understanding as the communities respond differently to the light intensity.
基金The China-ASEAN Maritime Cooperation Fund Project "China-ASEAN Countries Collaboration on Marine Endangered Species Researches" and "China-ASEAN Marine Protected Areas Ecosystem Management Network"Regional Demonstration of Marine Economy Innovative Development Project under contract No.16PZY002SF18+1 种基金the China-Indonesia Maritime Cooperation Fund Project "China-Indonesia Bitung Ecological Station Establishment"the National Natural Science Foundation of China under contract No.41506123
文摘Due to the elevated atmospheric carbon dioxide, ocean acidification(OA) has recently emerged as a research theme in marine biology due to an expected deleterious effect of altered seawater chemistry on calcification. A system simulating future OA scenario is crucial for OA-related studies. Here, we designed an OA-simulated system(OASys) with three solenoid-controlled CO_2 gas channels. The OASys can adjust the pH of the seawater by bubbling CO_2 gas into seawaters via feedback systems. The OASys is very simple in structure with an integrated design and is new-user friendly with the instruction. Moreover, the OASys can monitor and record real-time pH values and can maintain pH levels within 0.02 pH unit. In a 15-d experiment, the OASys was applied to simulate OA in which the expected target pH values were 8.00, 7.80 and 7.60 to study the calcifying response of Galaxea fascicularis. The results showed daily mean seawater pH values held at pH 8.00±0.01, 7.80±0.01 and 7.61±0.01 over15 d. Correspondingly, the coral calcification of G. fascicularis gradually decreased with reduced pH.
文摘Objective:To study the distribution and diversity of species and isolated molecules,according to their structure classes,from Indonesian marine organisms.Methods:This study was performed by using the SciFinder^(®)database,MarinLit and references from relevant articles from 1980 to 2014 which collected all the scientific publications dealing with the isolation of chemical compounds from Indonesian marine macroorganisms and microorganisms.Results:The discovery of novel compounds from Indonesian marine organisms gave us a result of a total of 78 papers.Alkaloids,terpenoids and peptides(84,67 and 15 new compounds,respectively)represented the three main chemical classes of compounds discovered from Indonesian marine organisms,and together with the other chemical classes showed a range of biological activities.Conclusions:The new marine compounds are mainly from sponges and soft corals.Alkaloids,terpenoids and peptides are the most prolific compounds isolated from Indonesian marine organisms.Most marine natural products from Indonesian organisms have been screened for anticancer or cytotoxicity activities.
基金Supported by the Riset Unggulan LIPI(Grant No.3403.02.066A).
文摘Objective:To find a potent antibiotic producer from the sponge-associated bacteria as well as to profile the important substances.Methods:Sponge collection,bacteria isolation,extraction and characterization of potent active compounds were carried out for this study.Results:Approximately 59 single strains of bacteria were isolated from this sponge.Totally 40 strains showed activity against Escerichia coli,Staphylococcus aureus and Vibrio eltor.The chemical separation of the potent strain Bacterium sp.Lb.10%.2.1.1.b,using n-phase column chromatography revealed 7 active fractions(7,8,9,10,11,14 and 15).The gas chromatography-mass spectrometer analysis of Fraction 7 indicated some phenolic compounds including 4-nonylphenol,methyl 3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate,acetosyringone,2,4-bis(1-phenylethyl)phenol,1,2-benzenedicarboxylic acid,mono(2-ethylhexyl)ester,tri(2-ethylhexyl)trimellitate and oleamide.Conclusions:Indeed,this is a preliminary information in profiling chemical substances,produced by Bacterium sp.Lb.10%.2.1.1.b.Further purification and structural chemical determination were needed to find a comprehensive result.