Species Dominance Index Research Articles

Analysis of hard coral condition on coral reef ecosystem in Ternate Island

Hard coral is a type of coral building structure in coral reef ecosystems. Hard coral is a coral reef entity that plays an important function in a coral reef ecosystem, especially related to physical and ecological functions in shallow marine waters environment. This study aimed to study percentages of coral cover, species life form, diversity index, dominance index, and distribution clusters of hard corals based on environmental parameters around Ternate Island. Hard coral cover sampling was carried out systematically using the underwater photo transect (UPT) method. The number of sampling stations were 30 location points with 750 photos. The method used for analyzing ecological conditions of hard corals was coral point count with excel extensions (CPCe). Environmental parameters measured included salinity, temperature, pH, brightness level, and dissolved oxygen. The distribution of hard coral clusters was analyzed statistically using the classify-hierarchical cluster. Study results showed that coral cover percentages ranged from 19% to 93% with an average cover of 67%, species diversity range was 7 to 40 species with an average of 19 species, diversity index (H ') with a value of 1.14 to 6.02 with an average of 2.07, dominance index (D) with a value of 0.13 to 0.53 with an average of 0.23. The results of the analysis of the distribution of hard corals consisted of four clusters. The study also found that distribution of hard coral clusters in Ternate Island was related to substrate topography.

Diversity Insects of Spring in Mutis Timau Nature Reserve, TTS District, NTT Province

Insect diversity is believed to be used as a bio-indicator of spring quality, this study aimed at determining the spring insect diversity around the Mutis Timau Nature Reserve. The study was conducted from June to August 2019. Insects were caught by using the yellow pan trap and hand sorting. The diversity of spring insects was determined based on the Shannon-Wiener diversity index (H'), species richness index (R1), species dominance index (D), and evenness index (E). The results showed that 16 species belong to 11 families, and five orders of insects. The families included Gryllidae, Gryllotalpidae, Tetrigidae, Formicidae, Pompilidae, Apidae, Ochteridae, Veliidae, Hydrometridae, Nepidae, Coenagrionidae, Libellulidae, Carabidae, and Coccinellidae. The Shannon-Wiener species diversity index and the wealth index of the species of springs were classified as moderate (H '= 2.12 and R1 = 4.19). There was no type of spring insects dominated (D = 0.23). All springs insects were found to have almost the same level of evenness (E<1), with a value of 0.76. Abiotic factors such as pH and soil temperature were within the tolerance range of spring insects. ÂÂ

Abundance and Diversity of Diatom Class Bacillariophyceae in the Waters of Tanjung Luar Fish Landing Based

Diatom class Bacillariophyceae are world wide distribution and commonly dominated the phytoplankton community. The community of diatom class Bacillariophyceae of the waters Tanjung Luar Fish Landing Based (FLB) has never been reported. This study aims to determine the abundance and diversity of diatom class Bacillariophyceae. The sampling sites were determined by using a systematic random sampling method. Data of diatom class Bacillariophyceae were analyzed for species abundance, species diversity index and species dominance index calculations. The results showed, that the abundance of diatom class Bacillariophyceae species were 322.000 ind/L (low category), the species diversity index of diatom class Bacillariophyceae was 2.162 (moderate category), and the species dominance index was 0.138 (none of species dominance).

Species Composition, Dominance and Similarity Index of Macrobrachium vollehovenii and M. Felicinum in Akor River, Ibere, Ikwuano, Nigeria

Occurrence and abundance of Macrobrachium vollehovenii and Macrobrachium felicinum were studied in Akor river, Ibere, Ikwuano, Nigeria. The area density method of sample collection was employed. The river was delineated into three stations: A, B and C and prawn specimen were collected fortnightly. Sample collection lasted for 24 months. Species composition, dominance and similarity index were calculated using standard methods. Chi square test was used to compare the dominance of both species in the River. Results showed that station A had a total catch composition of 1,407 (29.4%), station B recorded 1,689 (34.73%) and the highest catch was obtained in station C having 1,763 (36.2%). The overall total catch of 4,859 was recorded. Results also showed that M. vollehovenii dominated the river with a total number of 3,620 (75%) while M. felicinum had a total catch of 1,239 (25%). Ponderal index was 53.7 and 44.7 for M. vollehovenii and M. felicinum respectively and a similarity index of 1 for both species was observed. Statistical analysis showed that there was significant difference (p<0.05) between dominance of these species in Akor river. Inference from the results showed that these species are present as non-target organism in this river.
 Keywords: Occurrence, abundance, Macrobrachium species, fresh water, crustacean

The Diversity Of Fish Species In Inland Water Of Kampung (Village) Nasem In Merauke District

Wetland or stagnant swamp refers to an ecosystem of inland water that is vulnerable to population decline. Kampung Nasem in Merauke has quite promising fish resources. This research aimed to determine the diversity of fish species found in Kampung Nasem of Merauke. The fish sampling was performed for three months, from September to November 2017 at three research stations by functioning digital camera, ruler and manual as tools for documentation, while tool for fishing used gill net in the size of 1, 1.5, 2, 2.5, 3 and 4 inches; casting nets and scoop net. Fish found in the field were preserved with 10% formalin for identification purpose in the laboratory. The observed biological parameters were species richness, diversity index (H’), evenness index (E) and dominance index (C). The research finding obtained 15 fish species richness coprising 11 native fish species and 5 introduced fish species. The value of H’ was classified into moderate while the uniformity value was high, hence the fish were spread evenly in each research site and no species was found with domination. In addition, the Tilapia (Oreochromis niloticus) and Glass (Agrammus ambassadors) were species to have sufficient widespread distribution and numerous presence of presentation within the three research stations.

Amphibian Diversity (Order Anura) in Bogor, Indonesia Amphibian Diversity in Cimisblung Bogor West Java

Amphibians play a vital role as bio indicators of environmental health. This study aims to calculate the diversity of species, the abundance and the evenness of amphibians in the area of Cimisblung Resort Cisarua, Gunung Gede Pangrango National Park (TNGGP). Visual Encounter Surveys method was used to determine the species richness of the area, to compile a species list and to estimate the relative abundance of species, by observing the trunks of bush trees in the Cimisblung River flow. Data analysis used Species Diversity Index, Species Evenness Index, Species Abundance Index and Dominance Index. The results showed that the frogs obtained in the Cimisblung area were 151 individuals, 13 species from 5 families, the diversity index (Shannon-Wiener) showed that in the Cimisblung River H’ = 1.780 the evenness index for species E = 0.694 and the dominance index D = 0.286. Amphibian diversity (Order Anura) in the Cimisblung region is moderate.

STRUKTUR KOMUNITAS PADANG LAMUN DI PERAIRAN PANTAI PANDAWA, BALI

This research aimed to determine the types and structure of seagrass community based on species density, species relative density, diversity index, uniformity index, and dominance index of the seagrass. This research was conducted along Pandawa Beach, Kutuh Village, South Kuta District, Badung Regency, Bali from November to December 2019. Data of seagrass were collected from 3 line transects, 3 kuadran transects from each transect, repeated 3 times. Water quality data were collected 3 times within 4 weeks. Eight species of seagrass were identified, namely: Thalassia hemprichii, Cymodocea serrulata, Halodule pinifolia, Halodule uninervis, Halophila ovalis, Halophila decipiens, Syringodium isoetifolium, and Thalassodendron ciliatum. The highest species density found at station I that was Thalassodendron ciliatum, as well as for its relative density, and the lowest was Thalassia hemprichii. At station II and III, the highest species density was found on Cymodocea serrulata and the lowest was on Halophila ovalis. The study found that the species density of seagrasses at Pandawa Beach was categorized as high density, which dominated by Thalassodendron ciliatum at station I and by Cymodocea serrulata at station II and III. Diversity index of seagrass species at station I and II was categorized as medium species diversity and low species diversity for the station III. Dominance index of seagrass species at the three station was categorized as high dominance. Similarity index of seagrass species was categorized as medium or unstable community for the station I and II, and low similarity for the station III.

KEANEKARAGAMAN BINTANG LAUT (Asteroidea) DI PANTAI LAMALAKA KECAMATAN ILE BOLENG KABUPATEN FLORES TIMUR

Sea star is an invertebrate animal that is included in the phylum Echinoderms from the Asteroidea class. Radial symmetry is shaped and generally has five or more arms and does not have a frame that helps movement. This study aims to determine the diversity of sea star (Asteroidea) in Lamalaka Beach, Ile Boleng District, East Flores Regency.This research will be conducted in July-August 2019, the location of the study is on the Lamalaka coast, Ile Boleng District, East Flores Regency.The method used is a survey method, based on the presence of Asteroidea species that are considered to represent the area. The steps in data collection are field survey, observation, identifying species in each plot, observing and recording their marphological characteristics.Sampling uses the technique of determining the location of sampling using Area sampling. To identify based on Human and Deloach identification guidelines, 2010. Analysis of the data used in this research is quantitative descriptive and the composition of Asteroidea species can be stated based on visual observations calculating species density, relative density, and dominance index, diversity.Based on the results of the study, found 4 species of Asteroidea, namely Protoreaster nodulosus, Linckia laevigata, Echinaster luzonicus, Astropecten polyacanthus. The highest species density calculation results were found in P. nodulosus species with a value of 0.78 ind / m2. while the lowest species density was found in L.laevigata species with a value of 0.63 ind / m2. The highest relative density was found in P. nodulosus species with a value of 27.64%, and the lowest relative density found in L.laevigata species with a value of 22.35 %. The index of starfish species dominance in Lamalaka Beach, obtained a value of D <0.5, indicates that there are no species that dominate in Lamalaka Beach. The existence of starfish in Lamalaka Beach, Ile Boleng District, East Flores Regency needs to be preserved. One form of effort to preserve it is to conduct monitoring with routine monitoring to monitor the condition of the sea star population in these waters. Besides that, it is also necessary to increase the utilization of sea stars as one of the natural tourism objects and as an Ecoedutourism tourism object. Thus, the presence of starfish will be felt by the wider community so that awareness to maintain the existence of starfish will be increased.

The Dynamic of Blue-Green Algae (Cyanobacteria) in Eutrophic Tropical Waters, The Cirata Reservoir

The quality of reservoir waters depends on changes in their physical, chemical, and biological components. Changes in these parameters lead to the emerging of many problems in the reservoir, such as eutrophication and changes in the composition of the phytoplankton community in the reservoir ecosystem. This eutrophication impact can trigger an explosion of dangerous phytoplankton population, such as blue-green algae (Cyanobacteria). Research on the relationship between water quality and the community structure of Cyanobacteria has been carried out. This study used secondary data from the water monitoring report of the Cirata Reservoir from 2013-2017. This study aimed to obtain information on the community structure of Cyanobacteria and environmental parameters that affected the abundance of Cyanobacteria in the reservoir. Species abundance, diversity index, and dominance index were analyzed to determine changes in the community structure of Cyanobacteria in each of the years. Cyanobacteria abundances were classified using cluster analysis. Water quality parameters such as temperature, transparency, pH, carbon dioxide, nitrate, nitrite, and zooplankton abundance as independent variables, and levels of Cyanobacteria abundances as the dependent variable was analyzed using discriminant analysis. This study showed that the abundance of Cyanobacteria in the Cirata Reservoir is dominated by the Stanieria (a genus of the Pleurocapsales order) every year and the parameter that significantly affects the level of Cyanobacteria abundance was nitrate (NO3-N).

The Community of Chlorophyta as Bioindicator of Water Pollution in Pandanduri Dam District of Terara East Lombok

The Pandanduri Dam has a function as a support for agricultural irrigation water and also supports community activities so that it will affect the quality of its waters. The quality of the water needs to be analyzed because it can affect the aquatic ecosystem. This study aims to determine the level of water pollution in the Pandanduri Dam based on the phytoplankton community from the Chlorophyta Division. This type of research is descriptive exploratory. Sampling was carried out at 5 stations that were haphazardly selected with ecological representativeness consideration. Phytoplankton data were analyzed using the abundance formula, Shannon-Wiener diversity index, PIELOU uniformity index, and Simpson dominance index. The phytoplankton from the Chlorophyta Division found in the Pandanduri Dam were 14 species that are Pediastrum duplex var. Gracillimum, Gonium sp. 1, Gonium sp. 2, Coelastrum reticulatum, Scenedesmus acuminatus, Cosmarium sp., Chlamydomonas nasuta, Chlamydomonas sp., Selenastrum capricornutum, Monoraphidium dybowskii, Monoraphidium contortum, Monoraphidium irregular, Westella botryoides, and Kirchneriella lunaris consisting of 4 orders (Sphaeropleales, Chlorococcales, Chlamydomonadales and Desmidiales) and 10 genera (Pediastrum, Coelastrum, Scenedesmus, Gonium, Cosmarium, Chlamydomonas, Selenastrum, Monoraphidium, Westella, and Kirchneriella). The species diversity index of 2.21 is classified as moderate diversity, the species uniformity index is 0.83 which indicates even species growth, and the species dominance index indicates that no species dominates with a value of 0.12. The level of water pollution in the Pandanduri Dam was found in the moderate pollution category (oligotrophic).

Species composition, structure and endemicity of flora Malesiana in the Udayana urban forest, Mataram City

Udayana urban forest in Mataram City, West Nusa Tenggara (NTB) province boasts the endemic Flora Malesiana. This research aims to describe the structure, composition and the authenticity of Flora Malesiana in this area. We used a census method (100% measurement) to identify the species and measured the diameter and height of all trees species with the diameter of more than 2 cm. The results showed that the 64 species belong to 27 families. The urban forest is dominated by Fabaceae family (27.39%) with its 18 species (28.13%) of plants being invasive. The species dominance index (C) is in the range of 0.00012-0.24, indicating that there is no concentration of the species in the plant community. The ecology index showed a low level for seedling, a moderate to high level for sapling and pole, and a high level for trees. The horizontal structure is almost in the form of an inverted J-curve, neither a dynamic nor a natural forest. Vertical stand structure shows that the canopy stratification in the Udayana urban forest is mostly in stratum C (91.33%).

Ichthyofauna of Lake Buaya, South Sulawesi

Lake Buaya is one of the lakes located in the central part of South Sulawesi. Information about ichthyofauna biodiversity in this lake does not yet exist. Therefore, this study was conducted to analyze species composition, relative abundance, diversity index, evenness index, and dominance index, fish caught in the waters of Lake Buaya. This research was conducted in March to May 2019. Sampling was carried out four times over two months using a fishing gear with a mesh size of 2 inches. Sample analysis was carried out at the Fisheries Biology Laboratory, Faculty of Marine Sciences and Fisheries, Hasanuddin University. During the study 328 fish were found that belong to 12 species and 9 families. The highest abundance of individuals and relative fish abundance was found in Trichopodus pectoralis (snakeskin gourami). The range of diversity index, evenness index, and dominance index were 2,11–2,35, 0,85–0,95, and 0,10–0,15, respectively.

Phytosociological assessment and carbon stock estimation and valuation in the tropical dry deciduous forest of Bihar

Purpose This study aims to assess the biodiversity of the study area and estimate the carbon stock of two dry deciduous forest ranges of Banka Forest Division, Bihar, India. Design/methodology/approach The phytosociological analysis was performed and C stock estimation based on volume determination through nondestructive methods was done. Findings Phytosociological analysis found total 18,888 [14,893 < 10 cm (diameter at breast height) dbh] and 2,855 (1,783 < 10 cm dbh) individuals at Banka and Bounsi range with basal area of 181,035.00 cm2 and 32,743.76 cm2, respectively. Importance value index was highest for Shorea robusta in both the ranges. Species diversity index and dominance index, 1.89 and 1.017 at Banka and 1.99 and 5.600 at Bounsi indicated the prevalence of biotic pressure. Decreased dbh and tree height resulted in a lowered growing stock volume as 59,140.40 cm3 ha−1 (Banka) and 71,306.37 cm3 ha−1 (Bounsi). Total C stock at Banka and Bounsi range was 51.8 t ha-1 and 12.56 t ha−1, respectively where the highest C stock is recorded for Shorea robusta in both the ranges (9.8 t ha−1 and 2.54 t ha-1, respectively). A positive correlation between volume, total biomass and basal area of tree species with C stock was observed. R2 value for Banka range was 0.9269 (volume-C stock), 1 (total biomass-C stock) and 0.647 (basal area-C stock). Strong positive correlation was also established at Bounsi range with R2 value of 1. Considering the total forest area enumerated, C sequestration potential was about 194.25 t CO2 (Banka) and 45.9 t CO2 (Bounsi). The valuation of C stock was therefore US$2,525.25 (Banka) and US$596.70 (Bounsi). Practical implications The research found the potentiality of the study area to sequester carbon. However, for future, the degraded areas would require intervention of management strategies for restoration of degraded lands and protection of planted trees to increase the carbon sequestration potential of the area. Originality/value Present study is the first attempt to assess the phytosociology and estimate the regulatory services of forest with respect to biomass and carbon stock estimation for the Banka forest division of Bihar.

Taxonomic diversity, size-functional diversity, and species dominance interrelations in phytoplankton communities: a critical analysis of data interpretation

Species diversity, functional diversity, species richness, and dominance are fundamental topics in conservation ecology, but studies on their interrelationship remain underexplored and controversial issues in the literature. This investigation is a critical analysis focusing on the interrelations between species taxonomic diversity (based on the Shannon diversity index), cell size-based functional diversity (as a measure of Rao’sQ), species richness (number of species), and species dominance (as per McNaughton’s dominance index) in marine phytoplankton communities. The results revealed no statistical relationship between Shannon’s and Rao’sQ diversity indices, as well as no correlation between these indices and species richness. The importance of the applied functional diversity metric (Rao’sQ) for data interpretation and the misuse of species richness as a species diversity surrogate in the literature were discussed. The taxonomic composition and cell size of the dominant species and the dominant index over time were described. The species dominance index was related to Shannon’s species diversity and Rao’sQ functional diversity according to a negative linear regression, and the inverse correlation between these properties was statistically significant suggesting the species dominance control over the examined diversity system. Patterns across the data sets of species dominance and total community cell abundance showed resembling temporal fluctuations over a 2-year period, implying that species dominance may be a critical driver affecting temporal variations in total community cell abundance. This work provides a comprehensive critical evaluation of the link between taxonomic and functional diversity, and information on the importance of phytoplankton species dominance in maintaining ecosystem functioning.

Phytoplankton of Inner Ambon bay during east monsoon

The Inner Ambon Bay has a potency for fisheries resources, especially the anchovy of the genus Stolephorus. This species is depended on the abundance of plankton organisms as their food sources. The research was carried out on east monsoon and was aimed to analyze the species composition, abundance, diversity, similarity and spatial distribution of phytoplankton in Inner Ambon Bay. Sampling was done by towing the Kitahara plankton net vertically from the depth of 5 meters to surface water at 10 stations. Sixty-four species of phytoplankton was found during the sampling periods. The phytoplankton abundance varied between 5.4 × 104cells/m3 and 7.7 × 105cells/m3. The average values of species diversity index (H’), evenness index (J’) and dominance index (D) were 1.31, 0.37 and 0.63, respectively. Similarity between stations ranged from 53.4% to 85.5% and can be grouped into three clusters. Spatial distribution showed that station 5, station 6 and station 8 were more abundant compare to other stations.

Vegetation and ecoregion analysis at Sipirok Botanic Gardens, South Tapanuli, North Sumatra, Indonesia

Abstract. Siregar M, Purnomo DW, Siregar HM, Witono JR. 2020. Vegetation and ecoregion analysis at Sipirok Botanic Gardens, South Tapanuli, North Sumatra, Indonesia. Biodiversitas 21: 2526-2535. Botanic Gardens is an ex-situ plant conservation area. Enrichment of plant collections of Botanic Gardens in Indonesia is based on ecoregion types. To find out the type of ecoregion, the existing vegetation, main native species should be known. The research aimed to analyze the existing vegetation and ecoregion type at Sipirok Botanic Gardens. Existing vegetation has been carried out using a separate plot method 20x20 m which is placed on purposively in nine locations considered to have different vegetation types, namely remnant forest, young secondary forests and shrubs, rubber plantation, and grasslands. Around 66 species belonged to 45 genera and 27 families were found in vascular plants (dbh ≥ 10 cm). There were 66 species of sapling belonged to 54 genera and 35 families, and 110 seedlings belonged to 87 genera and 50 families. The tree species that have the highest Importance Value Index are Ficus sumatrana (PU-1), Myristica fatua (PU-3), Hevea brasiliensis (PU-4 and PU-7), Artocarpus elasticus (PU-8), and Knema cinerea (PU-9). No trees were found in young secondary forest/shrub plots and grasslands. Unlike the species dominance index, the species diversity index and species equitability index are higher in natural forest plots. Beta diversity based on Jaccard similarity index and Whittaker's index shows a relatively different species composition among plots. Cluster analysis shows the tendency of grouping in 2 types of communities, namely: a) remnant forest communities, and b) secondary communities. The natural forest community is further divided into two communities consisting of remnant forest tree species and industrial/plantation plant species also secondary tree species. Secondary communities are also further divided into secondary forest communities and grasslands. Based on ecoregion analysis using previous publications, altitude, and diversity of plant species in the study site, Sipirok Botanic Gardens is a transitional zone of the Sumatran lowland rainforest and mountain rainforest.

The effect of Paraquat Dichloride application on diversity and abundance of soil arthropods in the corn field

We investigated the effect of paraquat dichloride herbicide application on diversity and abundance of soil arthropods in a corn field. In addition to control (0 mL/L), four concentrations of paraquat dichloride were applied i.e. 3.33 mL / L, 4 mL / L, 4.66 mL / L and 5.33 mL / L. Sampling was carried out four times, namely at T 0 (before tillage), T 1 (after tillage), T 2 (after spraying herbicides), and T 3 (before harvesting) using a pitfall trap method. Soil arthropod samples were identified to the family level. The total number of individuals was then analyzed to obtain species richness, species dominance index, species diversity index and similarity index of Sorensen. The result showed that paraquat dichloride did not give any significant effect ( p> 0.05) on the number of individuals, species richness, species dominance index, diversity index and Sorensen similarity index of soil arthropods. The composition of soil arthropods in the control and in the treatment with the highest concentration shows a high level of similarity.

Assessment of environmental status of coastal mangrove area using macrobenthic assemblages: a study case at Tapak Mangrove area, Semarang, Central Java

Macrobenthic structure can be used as a bioindicator in determining the level of disturbance in water ecosystem through their composition, presence or absence spatially and temporally as apart of ecological management. Tapak is a coastal area of Semarang City, Central Java, Indonesia that has potency as an ecotourism area for integrated aquaculture at mangrove area. On the other hand, industrial activity around Tapak coastal area may lead to a degradation of the ecological function of that area. This study aims to assess environmental status at Tapak Mangrove Area through the macrobenthic structure in space and time. Purposive random sampling method was applied, consisting five sampling stations with 3 replicates between March to May 2018. Sediment samples were taken by using Ekman grab and were analyzed through the stages of fixation, rinsing, sieving, preservation, sorting, identification, and enumeration. The biotic parameters observed were the macrobenthic community structure, including species composition, abundance, and diversity, evenness, and dominance indices. Physico-chemical parameters of the water and sediment were measured every month. The Early Warning System (EWS-3SWJ) software was used to assess the level of environmental disturbance at each station. The total of 15 species of macrobenthic assemblages were found. The most common species were Telescopium telescopium, Cerithidea cingulata, and Metapenaeus sp.. The diversity of macrobenthos was considered low at all sampling stations (H’ = 0,56 – 1,52), with marked variability in dominant taxa (D = 0,21 – 0,71). Further analysis using the EWS-3SWJ showed that the environmental status of the Tapak Mangrove Area is categorized as slightly disturbed areas.

Ecological Analysis of Pacific White Shrimp (Litopenaeus Vannamei) Cultivation: Rokan Hilir and Dumai Context

The research was aimed to analyzed ecologically feasibility and prospective of Pacific white shrimp (Litopenaeus vannamei) cultivation in Rokan Hilir Regency and City of Dumai. The sudy was conducted from January 2017 to April 2018 in 5 sub-districts; Sungai Sembilan (City of Dumai), Sinaboi, Rimba Melintang, Bangko and Batu Hampar (Rokan Hilir District), Riau Province, Indonesia. Water samples were collected at the Senepis River, Nyamuk River, Sinaboi River, Teluk Dalam River, RKT plot and Camp Pemda in the Diamond Raya Timber concession area. It was noted; pH (5.22-7.0), salinity (5.0 to 22.5), phosphate (0.4-1.263 mg/L), ammonia (0.03-0.352 mg/L), nitrate (0.346-0.379 mg/L), CO2 (15.980-123.685 mg/L) DO (2.7-5.7 mg/L) COD (70.4-114.4 mg/L), BOD (4.85-6.4 mg/L) and number of Coliform bacterial cells (7.0-233.05 cfu/100 ml). The dominant species of fish caught in river waters are common species, as in zooplankton, phytoplankton, benthos, and manngrove community. Based on species data, abundancy index, diversity index, homogenity index and dominance index shows that the waters are still in normal condition. The study conclude the area is still in normal condition and suitable for Pacific white shrimp cultivation.

A comparative study of tree community structure and natural regeneration status in Bontang urban forest and conservation forest of the LNG Industrial Plant Area, East Kalimantan, Indonesia

Abstract. Sudrajat S, Dwiputro M. 2019. A comparative study of tree community structure and natural regeneration status in Bontang urban forest and conservation forest of the LNG Industrial Plant Area, East Kalimantan, Indonesia. Biodiversitas 20: 2841-2847. The objective of this study was to describe and compare the community structure and natural regeneration status of tree species in urban forests within industrial estates. This study was conducted in two types of forests, Bontang urban forests within industrial area and conservation forests in the Industrial buffer zone area. At each forest location, a transect was made, and along the transect, a plot of size 20 x 20 meters was made with a distance between plots of 100 meters. In each plot, several subplots were made with size of 5m x 5m for sapling level, and 2m x 2m for seedling level. The results of this study showed that in urban forest areas there were 32 tree-level species, 21 sapling species and 15 seedling species, belonging of 49 genera and 39 families. The number of species, species richness, species diversity, evenness of sapling and tree-level species was more in urban forests than in conservation forest, and the condition was vice versa for seedling level. The value of species dominance index in conservation forest was greater than urban forest, and conversely, the value of individual density/ha for tree-level was 562.50 individuals/ha, sapling level was 7,933 ind./Ha and for seeding level 80,625 ind./ha. Of the 53 urban forest species, 28 species (52.83%) were in no regeneration category, 3 species (5.66%) were in poor regeneration category, and 22 species (41.50%) were in the new species category. In contrast, among 76 species of the conservation forests, 8 species (10.52%) showed good regeneration status, 13 species (17.10%) showed poor status and 55 species (72.36%) showed no regeneration status. From the results, it can be concluded that the Bontang urban forest in the industrial area shows no regeneration status and the emergence of new species. In the context of conservation, it is recommended to implement special silvicultural techniques to maintain the biodiversity of this urban forest.