scholarly journals FORAMINIFERA BENTIK TERKAIT DENGAN KONDISI LINGKUNGAN PERAIRAN SEKITAR PULAU DAMAR, KEPULAUAN SERIBU

2016 ◽  
Vol 13 (3) ◽  
pp. 165 ◽  
Author(s):  
Suhartini M. Natsir ◽  
Kresna Tri Dewi
Keyword(s):  
Cluster Analysis ◽  
Community Structure ◽  
Coral Reef ◽  
Hierarchical Cluster Analysis ◽  
Benthic Foraminifera ◽  
Diversity Index ◽  
Good Condition ◽  
Hierarchical Cluster ◽  
Shallow Waters ◽  
Environmental Condition

Secara umum, kondisi lingkungan perairan di bagian Selatan Kepulauan Seribu cenderung lebih rendah dibandingkan dengan bagian Utara karena pengaruh polusi dari daratan. Salah satu pulau yang terletak di bagian selatan tersebut adalah Pulau Damar Besar. Penelitian ini bertujuan untuk mengetahui sebaran foraminifera bentik di perairan Pulau Damar Besar, Kepulauan Seribu terkait dengan kondisi lingkungan setempat. Dari 12 stasiun pengambilan sampel, teridentifikasi 64 spesies dari 10968 individu foraminifera bentik. Beberapa spesies foraminifera yang dijumpai hidup bersimbiosis dengan terumbu karang, seperti Amphistegina lessonii, Amphistegina radiata, Sorites marginalis, Heterostegina sp., dan Calcarina calcar. Berdasarkan indeks keragaman, keseragaman dan dominansi, struktur komunitas di foraminifera bentik di Pulau Damar Besar cenderung seragam. Namun berdasarkan hierarchical cluster analysis diperoleh empat kelompok sebaran dengan penciri masing-masing yang berbeda. Nilai indeks diversitas sekitar 3,48-3,84 yang menunjukkan lingkungan perairan di sekitar pulau ini dalam kondisi bagus. Kata kunci sebaran, Foraminifera bentik, Pulau Damar Besar dan Kepulauan Seribu In general, the marine environment in the southern part of the Seribu Islands is less good condition than the northern part due to the influence of pollution from the mainland. One of the islands in this southern part is Damar Besar Island. The purpose of this study is to recognize foraminiferal distribution from this island related to its environmental condition. From 12 sampling stations, it can be identified 64 species from 10968 individuals of benthic foraminifera. Several species are associated with coral reef such as Amphistegina lessonii, Amphistegina radiata, Sorites marginalis, Heterostegina sp., dan Calcarina calcar. Based on the diversity, evenness and dominance indexes, it seems that the community structure of benthic foraminifera in the study area tends to be equal. However, based on hierarchical cluster analysis, it is resulted four groups of distribution that characterized by their own shallow waters species. The diversity index is 3,48-3,84 that shows good environmental condition in the study area. Keywords: distribution, benthic foraminifera, Damar Besar Island and Seribu Islands.

scholarly journals FORAMINIFERA BENTONIK KAITANNYA DENGAN KUALITAS PERAIRAN DI WILAYAH BARAT DAYA PULAU MOROTAI, MALUKU UTARA

2017 ◽  
Vol 14 (1) ◽  
Author(s):  
Amir Sidiq ◽  
Suwarno Hadisusanto ◽  
Kresna Tri Dewi
Keyword(s):  
Water Quality ◽  
Community Structure ◽  
Coral Reef ◽  
Water Depth ◽  
Diversity Index ◽  
Coral Triangle ◽  
Environmental Condition ◽  
Evenness Index ◽  
Shore Station ◽  
Near Shore

Pulau Morotai, Maluku Utara merupakan salah satu pulau yang terletak di kawasan segitiga terumbu karang  sebagai pusat kenakeragaman biota laut global. Kesehatan ekosistem terumbu karang dapat dipantau dengan menggunakan komposisi foraminifera bentonik. Maksud dan tujuan studi ini adalah untuk mengetahui struktur komunitas foraminifera bentoni terkait dengan kualitas perairan sebelah barat daya Pulau Morotai. Studi ini menggunakan enam sampel sedimen dasar laut dengan tiga kali perulangan yang diambil pada  kedalaman antara 16 dan 36 m. Hasilnya menunjukkan ada 28 spesies foraminifera bentonik, dicirikan oleh kehadiran Amphistegina dan Operculina dalam jumlah sangat melimpah. Amphistegina radiata merupakan spesies dengan densitas tertinggi di stasiun dekat pantai. Nilai indeks keanekaragaman foraminifera antara 1,49 dan 2,31 yang tergolong dalam kondisidengan tingkat keanekaragaman sedang. Indeks keseragaman umumnya lebih besar dari 0,6 yang menunjukkan lingkungan stabil. Nilai indeks FORAM (FI) berkisar dari 6,32 hingga 9,16 yang memperlihatkan  kondisi lingkungan yang kondusif bagi pertumbuhan terumbu karang. Kata kunci: struktur komunitas, foraminifera bentonik, terumbu karang, MorotaiMorotai Island, North Molucca is one of islands that is located in the Coral triangle region as the global centre of marine biodiversity.  The health of this coral ecosystem could be monitored by using benthonic foraminferal composition. The purpose of this study are re recognized community structure of benthic foraminifera related to water quality off southwest Morotai, Island. This study used six marine sediments samples with three times of replication that collected from 16 -36 m water depth. The result shows that there are 28 spesies of benthonic foraminifera characterized by occurences of Amphistegina and Operculina abundantly. Amphistegina radiata is a highest density species that is found in the near shore station. The diversity index is between 1,49 and 2,31 as moderate diversity;  evenness index generally is more than 0,6 that indicates stable environment. FORAM index (FI) is more than 4 (6,32 to 9,16) that shows of  condusif environmental condition for reef growth.Keywords: community structure, benthonic foraminifera, coral reef, Morotai

scholarly journals The study of the transformation of segetal flora richness and diversity in selected habitats of southern Poland over a 20-year interval

2017 ◽  
Vol 70 (2) ◽  
Author(s):  
Teresa Dąbkowska ◽  
Monika Grabowska-Orządała ◽  
Teofil Łabza
Keyword(s):  
Cluster Analysis ◽  
Species Richness ◽  
Hierarchical Cluster Analysis ◽  
Diversity Index ◽  
Hierarchical Cluster ◽  
Habitat Conditions ◽  
Weed Communities ◽  
Mountain Habitats ◽  
Weed Flora ◽  
Segetal Flora

<p>The aim of study was to evaluate diversity of segetal flora and its transformations over a more than 20-year period in 19 field habitats representative for cereal crops of southern Poland. The research hypothesis assumed that: (<em><strong>i</strong></em>) the diversity of habitat conditions determines the abundance of arable land flora, (<em><strong>ii</strong></em>) it also affects farming intensity which is the main cause of the decline in the biodiversity of agrocoenoses.</p><p>Based on 415 phytosociological relevés (sampled using the Braun-Blanquet method), weed species richness (Sr), phytosociological constancy of species (S), cover index (<em>D</em>), Shannon’s diversity index (<em>H</em>) and Simpson’s dominance index (<em>C</em>) were determined. Measurements were done for each habitat during two research periods. The results were subjected to ANOVA analysis. To assess the similarities of the studied habitats’ weed flora in each period and their changes over time, Ward’s hierarchical cluster analysis was used. The distance matrix was calculated from Jaccard’s similarity indices. The results are presented in the form of hierarchical trees.</p><p>The study showed that species richness of the weed communities and their diversity were strongly determined by habitat conditions. Preservation of the value of the diversity index and even its increase (especially in a considerable part of mountain habitats) showed that extensive methods of reducing weed infestation had remained at a similar level of efficacy during the 20-year interval. Hierarchical cluster analysis showed differences between the first and second study period in the weed communities for habitats of lowland soil complexes. The exception were the habitats with the greatest potential for crop cultivation, located on chernozems and rendzinas. In the mountain habitats, there were no significant changes in the segetal flora during the study interval. An increase in weed flora abundance indicates a lack of threats to the diversity of agrophytocoenoses in this part of Poland.</p>

Extraordinary circumstances: Covid-19 – Italian Serie A scenario

2021 ◽  
pp. 175433712110192
Author(s):  
Milan Radojicic ◽  
Aleksandar Djokovic ◽  
Nikola Cvetkovic
Keyword(s):  
Cluster Analysis ◽  
Hierarchical Cluster Analysis ◽  
Hierarchical Cluster ◽  
Round Robin ◽  
The Past ◽  
Novel Approach ◽  
Round Robin Tournaments

Unpredictable and uncontrollable situations have happened throughout history. Inevitably, such situations have an impact on various spheres of life. The coronavirus disease 2019 has affected many of them, including sports. The ban on social gatherings has caused the cancellation of many sports competitions. This paper proposes a methodology based on hierarchical cluster analysis (HCA) that can be applied when a need occurs to end an interrupted tournament and the conditions for playing the remaining matches are far from ideal. The proposed methodology is based on how to conclude the season for Serie A, a top-division football league in Italy. The analysis showed that it is reasonable to play 14 instead of the 124 remaining matches of the 2019–2020 season to conclude the championship. The proposed methodology was tested on the past 10 seasons of the Serie A, and its effectiveness was confirmed. This novel approach can be used in any other sport where round-robin tournaments exist.

scholarly journals Detection of drought events in Greece using daily precipitation

2010 ◽  
Vol 41 (2) ◽  
pp. 126-133 ◽  
Author(s):  
N. Kalamaras ◽  
H. Michalopoulou ◽  
H. R. Byun
Keyword(s):  
Cluster Analysis ◽  
Hierarchical Cluster Analysis ◽  
Daily Precipitation ◽  
Hierarchical Cluster ◽  
Seasonal Distribution ◽  
Drought Severity ◽  
Severe Drought ◽  
Analysis Method ◽  
Cluster Analysis Method ◽  
Insight Into

In this study a method proposed by Byun & Wilhite, which estimates drought severity and duration using daily precipitation values, is applied to data from stations at different locations in Greece. Subsequently, a series of indices is calculated to facilitate the detection of drought events at these sites. The results provide insight into the trend of drought severity in the region. In addition, the seasonal distribution of days with moderate and severe drought is examined. Finally, the Hierarchical Cluster Analysis method is used to identify sites with similar drought features.

An investigation on conceptual understanding about cosmology

2019 ◽  
Vol 15 (S367) ◽  
pp. 397-399
Author(s):  
Arturo Colantonio ◽  
Irene Marzoli ◽  
Italo Testa ◽  
Emanuella Puddu
Keyword(s):  
High School ◽  
Cluster Analysis ◽  
High School Students ◽  
Conceptual Understanding ◽  
Hierarchical Cluster Analysis ◽  
Hierarchical Cluster ◽  
Content Area ◽  
School Students ◽  
Convenience Sample ◽  
Teaching Activities

AbstractIn this study, we identify patterns among students beliefs and ideas in cosmology, in order to frame meaningful and more effective teaching activities in this amazing content area. We involve a convenience sample of 432 high school students. We analyze students’ responses to an open-ended questionnaire with a non-hierarchical cluster analysis using the k-means algorithm.

Hierarchical Cluster Analysis Identifies Distinct Physiological States After Acute Brain Injury

2021 ◽  
Author(s):  
Swarna Rajagopalan ◽  
Wesley Baker ◽  
Elizabeth Mahanna-Gabrielli ◽  
Andrew William Kofke ◽  
Ramani Balu
Keyword(s):  
Cluster Analysis ◽  
Brain Injury ◽  
Hierarchical Cluster Analysis ◽  
Hierarchical Cluster ◽  
Acute Brain Injury
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