Community structure of nudibranchs (Gastropoda) at Coastal Waters of Waleo Village (Mollucas Sea) and Kalasey Village (Manado Bay, Sulawesi Sea)

2013 ◽  
Vol 1 (1) ◽  
pp. 21 ◽  
Author(s):  
Aprillawati Purba ◽  
Janny D Kusen ◽  
N Gustaf F Mamangkey
Keyword(s):  
Community Structure ◽  
Coral Reefs ◽  
Coastal Waters ◽  
Line Transect ◽  
Community Structures ◽  
The Difference ◽  
Study Sites ◽  
Simultaneous Hermaphrodites

Nudibranchia are mollusks without a shell. They are simultaneous hermaphrodites and are carnivores while some of them are cannibals. Nudibranchia are frequent occupants and foraging on coral reefs. The study was conducted at two locations, namely Waleo Village Waters representing the waters of Mollucas and Sulawesi Sea was represented by Kalasey Village. The difference in the location of the two waters is expected to affect the existence of community structures. The present study includes diversity, richness, evenness, dominance and similarity. A line transect was used to collect data. We found 84 individuals from both study sites representing 8 species of Nudibranchia, which fall into 4 genera and 3 families namely, Pteraeolididae, Phyllidiidae, and Chromodorididae. The most common family was the Phyllidiidae. The similarity value at both locations was 54.5%© Penelitian tentang struktur komunitas gastropoda nudibranchia telah dilakukan di dua lokasi yaitu Desa Waleo (Laut Maluku) dan Desa Kalasey (Laut Sulawesi). Struktur komunitas yang dikaji meliputi studi keanekaragaman, kekayaan, kemerataan, dominansi dan kesamaan. Metode yang digunakan dalam penelitian adalah line transect. Hasil penelitian menunjukkan, dari kedua lokasi, ditemukan 84 individu yang terdiri dari 8 jenis yang masuk dalam 4 genera dan 3 famili (Pteraeolididae, Phyllidiidae, dan Chromodorididae). Famili Phyllidiidae adalah yang paling umum ditemukan. Nilai kesamaan di kedua lokasi adalah 54,5%©

Formation and succession of microbial community structure in different ecological niches under reclaimed water acclimation

2020 ◽  
Author(s):  
Jie Li ◽  
Yujiao Sun ◽  
Xiaoyu Wang ◽  
Meng Yin ◽  
Shangwei Xu
Keyword(s):  
Community Structure ◽  
Microbial Community ◽  
Water Resources ◽  
Natural Water ◽  
Reclaimed Water ◽  
Ecological Niches ◽  
Community Structures ◽  
Significant Difference ◽  
Microbial Community Structures ◽  
The Difference

<p>Using reclaimed water as a resource for landscape water replenishment may alleviate the major problems of water resource shortages and water environment pollution. However, the safety of the water and the risk of eutrophication remain doubted by the public. Our study aimed to reveal the difference between natural water and reclaimed water and to discuss the rationality of reclaimed water replenishment from the perspective of microorganisms. We analyzed the microbial community structures in natural water, reclaimed water and natural biofilms and the community succession was clarified along the ecological niches, water resources, liquidity and time using 16S rRNA gene amplicon sequencing. Primary biofilms without the original community were added to study the formation of microbial community structures under reclaimed water acclimation. The results showed that the difference caused by ecological niches was more than those caused by the liquidity of water and different water resources. No significant difference was found in the microbial diversity and community structure caused by the addition of reclaimed water. Based on the microbial analysis, reclaimed water replenishment is a feasible solution that can be used for supplying river water. Innovatively, we introduced the study of biofilms and determined that the monitoring of biofilms or sediments closely related to water was also important for the early warning of water bloom, providing a unique perspective for the management of eutrophication.</p>

scholarly journals DIVERSITY OF STONY CORALS IN BANGGAI WATER

2015 ◽  
Vol 38 (1) ◽  
pp. 9-19 ◽  
Author(s):  
Rikoh Manogar Siringoringo ◽  
Tri Aryono Hadi
Keyword(s):  
Coral Reefs ◽  
Coral Species ◽  
Line Transect ◽  
Coral Triangle ◽  
Stony Corals ◽  
Study Sites ◽  
The Given ◽  
Central Sulawesi

Banggai waters, located in Central Sulawesi Province, is part of the world’s coral triangle area which is well–known to have the highest diversity on stony corals (Scleractinia). A research on stony corals has been carried out at 9 study sites between June–July 2011, practicing line transect methods and free collection in order to determine the recent condition and diversity of the given coral group. The average of live corals coverage was recorded at 46%(ranging between 24–77%), and categorized as fair condition. The number of coral species found was 194, distributed in 54 genera. The Banggai waters condition was considered good and potential to sustain the corals’growth. Even though so, in several particular areas, there were still threats on coral reefs.

Urban community structure detection based on the OD of traffic analysis zones

2019 ◽  
Vol 33 (13) ◽  
pp. 1950164
Author(s):  
Qing-Feng Dong ◽  
Dian-Kun Chen ◽  
Ting Wang
Keyword(s):  
Community Structure ◽  
Quantitative Methods ◽  
Urban Community ◽  
Spatial Location ◽  
Traffic Analysis ◽  
Association Mining ◽  
Community Structures ◽  
City Community ◽  
Traffic Characteristics ◽  
Structure Detection

At present, the detection of urban community structures is mainly based on existing administrative divisions, and is performed using qualitative methods. The lack of quantitative methods makes it difficult to judge the rationality of urban community divisions. In this study, we used complex network association mining methods to detect a city community structure by using the Origin-Destinations (OD) at traffic analysis zone (TAZ) level, and successively assigned all the TAZs into different communities. Based on the community results, we calculated the community core degree of each TAZ within every community, and then calculated the Traffic Core Degree and Location Core Degree indicators of the community based on OD passenger flow and spatial location relationship between communities. Finally, we analyzed the correlation among three indicators to ensure the rationality of the community structure. We used the city of Zhengzhou in 2016 as an example case study. For Zhengzhou, we detected a total of six communities. We found a relatively low correlation between Traffic Core Degree and Location Core Degree. Within each group, the correlation between community core degree and Traffic Core Degree was higher than that between community core degree and Location Core Degree, indicating that the urban community structure is more reasonably based on traffic characteristics. The development of a quantitative approach for determining reasonable city community structures has important implications for transportation planning and industrial layout.

Community Detection in Political Discussions on Twitter

2016 ◽  
Vol 35 (2) ◽  
pp. 244-261 ◽  
Author(s):  
Frederic Guerrero-Solé
Keyword(s):  
Community Structure ◽  
Community Detection ◽  
Reliable Method ◽  
Community Structures ◽  
Network Community ◽  
High Polarization

In November 9, 2014, the Catalan government called Catalan people to participate in a straw poll about the independence of Catalonia from Spain. This article analyzes the use of Twitter between November 8 and 10, 2014. Drawing on a methodology developed by Guerrero-Solé, Corominas-Murtra, and Lopez-Gonzalez, this work examines the structure of the retweet overlap network (RON), formed by those users whose communities of retweeters have nonzero overlapping, to detect the community structure of the network. The results show a high polarization of the resulting network and prove that the RON is a reliable method to determinate network community structures and users’ political leaning in political discussions.

scholarly journals Community structure, life histories and secondary production of stoneflies in two small mountain streams with different degree of forest cover

2015 ◽  
Author(s):  
Pavel Beracko ◽  
Andrea Kušnírová ◽  
Michaela Partlová ◽  
Jana Ciceková
Keyword(s):  
Community Structure ◽  
Secondary Production ◽  
Life Histories ◽  
Forest Cover ◽  
Adult Emergence ◽  
Life Cycles ◽  
Mountain Streams ◽  
Annual Life Cycle ◽  
Forested Stream ◽  
The Difference

<p>Our study examines community structure and nymphal biology (life cycles and secondary production) of stoneflies in two adjacent mountain streams with different degree of forest cover in the Prosiečanka River Basin (Chočské Vrchy Mts., West Carpathians). One of the streams has non-forested catchment, converted to meadows and pastures, while the other one has catchment with 60% covered by spruce forest. Differences in forest cover and in thermal regime of the streams were reflected by the difference of stonefly communities at their structural and functional level. Species <em>Nemoura cinerea and Leuctra aurita </em>created stonefly assemblage in non-forested stream, whereas <em>Nemoura cinerea</em> also occurred in naturally forested stream together with species <em>Leuctra armata, Leuctra nigra, Leuctra prima, Siphonoperla neglecta</em> and <em>Arcynopteryx dichroa</em>. All examined species had maximally annual life cycle and in eudominant species <em>Nemoura cinerea</em> one month shift was found in nymphal hatching and adult emergence between streams. Total secondary production of stoneflies in undisturbed stream (126.46 mg DW m<sup>-2</sup> y<sup>-1</sup>) was more than two times higher than the production in non-forested stream (47.39 mg DW m<sup>-2</sup> y<sup>-1</sup>). </p>

scholarly journals Preliminary Study on Fish Larvae at Selected Coastal Waters of Sarawak

1970 ◽  
Vol 4 (2) ◽  
pp. 1-8
Author(s):  
Norhakimi Muhamad ◽  
Siti Akmar Khadijah Ab Rahim
Keyword(s):  
Coastal Waters ◽  
Intertidal Zone ◽  
Larval Dispersal ◽  
Sampling Methods ◽  
Fish Larvae ◽  
Mesh Size ◽  
Subtidal Zone ◽  
Preliminary Study ◽  
Study Sites

A survey were carried out from April to November 2012 at five study sites namely Teluk Pandan beach, Rambungan beach, Puteri beach, Sampadi Island and Satang Besar Island, Sarawak. This survey was carried out in order to obtain early documentation of fish larvae at selected coastal waters of Sarawak. Seine net (1 mm mesh size) which was pulled by two persons at intertidal zone; and bridle net (0.5 mm mesh size) that was towed by boat at subtidal zone (Sampadi Island only) were used to collect the samples. A total of 2,562 fish larvae which comprise 25 families were obtained from both sampling methods. A total of 16 families of fish larvae were caught by seine net from the intertidal zone. The same number of families was collected at the subtidal zone of Sampadi Island by bridle net. Ambassidae, Clupeidae, Engraulidae and Gerreidae found to be dominant families in the study sites. Clupeidae and Gerreidae shown a wide larval dispersal area because they were collected at all study sites. These findings seem to indicate that the subtidal zone of Sampadi support more species of fish larvae.

scholarly journals New Records of Seagrass Flora in Air Bangis West Sumatera

2012 ◽  
Vol 13 (1) ◽  
pp. 77
Author(s):  
Eni Kamal ◽  
Japar Sidik Bujang ◽  
Muta Hara Zakaria
Keyword(s):  
Coral Reefs ◽  
West Coast ◽  
Coastal Waters ◽  
New Record ◽  
New Records ◽  
Thalassia Hemprichii ◽  
Habitat Characteristic ◽  
Halodule Uninervis ◽  
Width Measurements ◽  
Shallow Coastal Waters

Seagrasses in the Air Bangis Archipelago, west coast of Sumatra were found growing in sandy muddy substratesof the shallow coastal waters at depth of 0.3-2.5 m, dominated by degraded coral reefs around the off-shoreislands. Two species; Enhalus acoroides (L.f) Royle and Thalassia hemprichii (Ehrenb) Aschers were observed atPulau Unggas, Pulau Pasir Panjang and Teluk Tapang. Halodule uninervis (Forssk) Aschers was observed in twolocations; Pasir Panjang and Teluk Tapang. The occurrence of this species is unknown previously and therefore itis a new flora record for Sumatra. With this new record, Sumatra has six species of seagrasses, contributing tohalf of total number of seagrasses occurring in Indonesia. According to leaf width measurements, two morphologicalvariants (narrow and wide leaved) can be distinguished for Halodule uninervis. In addition, descriptions of thespecies and their habitat characteristic are provided.

scholarly journals High-throughput amplicon sequencing reveals the spatiotemporal effects, abiotic and biotic shaping factors for the microbial communities in tropical mangrove sediments in Sanya, China

2020 ◽  
Author(s):  
Wu Qu ◽  
Boliang Gao ◽  
Jie Wu ◽  
Min Jin ◽  
Jianxin Wang ◽  
...  
Keyword(s):  
Community Structure ◽  
Microbial Community ◽  
Microbial Communities ◽  
Fungal Community ◽  
Amplicon Sequencing ◽  
Biotic Factors ◽  
Community Structures ◽  
Mangrove Sediments ◽  
Element Cycling ◽  
Microbial Community Structures

Abstract Background Microbial roles in element cycling and nutrient providing are crucial for mangrove ecosystems and serve as important regulators for climate change in Earth ecosystem. However, some key information about the spatiotemporal influences and abiotic and biotic shaping factors for the microbial communities in mangrove sediments remains lacking. Methods In this work, 22 sediment samples were collected from multiple spatiotemporal dimensions, including three locations, two depths, and four seasons, and the bacterial, archaeal, and fungal community structures in these samples were studied using amplicon sequencing. Results The microbial community structures were varied in the samples from different depths and locations based on the results of LDA effect size analysis, principal coordinate analysis, the analysis of similarities, and permutational multivariate ANOVA. However, these microbial community structures were stable among the seasonal samples. Linear fitting models and Mantel test showed that among the 13 environmental factors measured in this study, the sediment particle size (PS) was the key abiotic shaping factor for the bacterial, archaeal, or fungal community structure. Besides PS, salinity and humidity were also significant impact factors according to the canonical correlation analysis (p ≤ 0.05). Co-occurrence networks demonstrated that the bacteria assigned into phyla Ignavibacteriae, Proteobacteria, Bacteroidetes, Chloroflexi, and Acidobacteria were the key biotic factors for shaping the bacterial community in mangrove sediments. Conclusions This work showed the variability on spatial dimensions and the stability on temporal dimension for the bacterial, archaeal, or fungal microbial community structure, indicating that the tropical mangrove sediments are versatile but stable environments. PS served as the key abiotic factor could indirectly participate in material circulation in mangroves by influencing microbial community structures, along with salinity and humidity. The bacteria as key biotic factors were found with the abilities of photosynthesis, polysaccharide degradation, or nitrogen fixation, which were potential indicators for monitoring mangrove health, as well as crucial participants in the storage of mangrove blue carbons and mitigation of climate warming. This study expanded the knowledge of mangroves for the spatiotemporal variation, distribution, and regulation of the microbial community structures, thus further elucidating the microbial roles in mangrove management and climate regulation.

scholarly journals STUDI EKOLOGI SUMBERDAYA TERIPANG DI NEGERI PORTO PULAU SAPARUA MALUKU TENGAH

2014 ◽  
Vol 1 (1) ◽  
pp. 32-42
Author(s):  
Yona Aksa Lewerissa
Keyword(s):  
Sea Cucumber ◽  
Water Environment ◽  
Turbidity Current ◽  
Line Transect ◽  
Community Structures ◽  
Sea Cucumbers ◽  
Environment Factors ◽  
Line Transect Method ◽  
Environment Measurement

Background: Decreasing of sea cucumber resources on numbers and size of fishing capture in Negeri Porto waters influenced its community structures. Further, water environment steadiness will questionable. For this reason, study was done to analyzed community structures of sea cucumbers include of numbers species found, density, potency, species presence frequency, distribute pattern, ecology index and environment measurement. Method: Research done on February to May, 2008 at Negeri Porto used Line Transect Method. Result: showed there were eight species of sea cucumbers found (potency as much as 12.286 individuals). Bohadschia marmorata got highest in numbers species found, density, potency and species presence frequency. There were three distribute pattern of sea cucumbers found wich are uniform, random and group. Conclusion: Sea cucumbers diversity was in lower, species are closed to compatible. B. marmorata and Holothuria edulis are tends to dominate this water. Environment factors such temperature, pH, salinity, DO, turbidity, current and sediment distribute showed that Porto waters was suitable to sea cucumbers growth.

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