Evenness Index Values Research Articles

CATCHABILITY AND DIVERSITY OF FISH SPECIES CAPTURED BY GILL NET IN NEW CALABAR RIVER, NIGERIA

The aim of this study was to analyze fish species caught by gill nets and fish diversity of the New Calabar River. Three sampling stations were set based on the coverage situation of the river and ichthyofauna associated with gill nets were sampled twice monthly from February to July 2018. A total of 3,251 fish specimens, representing 11 orders, 15 families, and 28 species, were captured. The order Perciformes was identified as the most abundant representing five families while the remaining had one family each. The fish family Cichlidae was the most represented with seven species, and other notable families were Alestidae, Clupeidae, and Mugilidae, representing three species each. Prominent among the fish caught monthly included Liza falcipinnis, Mugil cephalus, Sarotherodon melanotheron, Sarotherodon galilaeus, Coptodon guineensis, and Sardinella maderensis. The mean catch per unit effort (CpUE) ranged from 3.15±0.2 to 4.85±0.2 kg unit-1 day11. Results of diversity indices revealed that Shannon-Wiener index values varied between 2.64 and 2.82, Simpson diversity ranged from 0.07 to 0.10, and Pielou’s evenness index values ranged from 0.85 to 0.95. The values obtained in this study showed that the status of fish diversity in New Calabar River was stable.

DIVERSITY OF FISH LARVAE AROUND THE ESTUARY OF THE BANYUASIN RIVER, SOUTH SUMATERA PROVINCE

The initial phase of the fish life cycle is a critical phase associated with high mortality due to sensitivity to predators, food availability, and also environmental changes that occur in nature. Disruption of the initial stages of fish life has a negative impact on fish populations. Until now there has been no information about fish larvae around the Banyuasin River Estuary. Therefore, research is needed on the diversity of fish larvae around the Banyuasin River Estuary, South Sumatra Province. This research were used purposive sampling method, sampling technique in the form of Cruise Track Design with continuous parallel survey trajectory. Based on the results of the study found as many as 10 families consisting of 1483 individuals of fish larvae in March and 1013 individuals of fish larvae in May consisting of Engraulidae 1,601 individuals of fish larvae, Mungiloidei as many as 109 individuals, Leiognathidae 50 individuals, Chanidae 453 individuals, Scatophagidae 20 individuals , Belonidae 39 individuals, Gobioididae 5 individuals, Chandidae 183 individuals, Syngnatihidae 6 individuals, and Gobiidae 30 individuals fish larvae. The index value of fish larvae diversity is classified as medium category (March 1.02 and May 1.12), Morisita index shows the distribution pattern of fish larvae classified as a group (March 0-14.17 and May 2.43-10.40 ), and the evenness index value is in the medium category (March 0.437 and May 0.521).

Exogenously applied ferulic acid and p-coumaric acid differentially affect cucumber rhizosphere Trichoderma spp. community structure and abundance

Continuous monocropping can cause the buildup of autotoxins (e.g., phenolic compounds) in the soil, which can alter soil microbial community and inhibit plant growth. However, how different phenolic compounds affect certain soil microbiota is unclear. Here, we studied the response of cucumber rhizosphere Trichoderma spp. community to exogenously applied ferulic and p-coumaric acids by polymerase chain reaction denaturing gradient gel electrophoresis (PCR-DGGE) and real-time PCR techniques. Results showed that ferulic acid, but not p-coumaric acid, increased the Trichoderma spp. abundance, and this increase were positively correlated with ferulic acid concentration. Moreover, ferulic acid changed the community structure, increased the number of DGGE bands, Shannon wiener, and evenness index values, while p-coumaric acid had no effect on all these parameters of Trichoderma spp. community. These results suggest that these two phenolic acids affected Trichoderma spp. differentially at the community level.

Zooplankton diversity of three dam lakes in Turkey

Abundance, community composition, diversity and density of zooplankton were analysed in Tercan, Kuzgun and Demirdoven Dam Lakes between January-December 2014 seasonally. During the study period a total of 38 zooplankton species have been observed, with 25 species of Rotifera, and 8 species of Cladocera and 5 species of Copepoda. 28 species in Tercan Dam Lake, 26 species in Kuzgun Dam Lake and 27 species in Demirdoven Dam Lake were identified. Rotifers were the dominant group among zooplankton community, constituting 65.7% of the total zooplankton population. The highest (H′=2.75) and the lowest (H′=0.68) Shannon diversity index values were recorded at Demirdoven Dam Lake. And also the highest value of Simpson index (D=11.63) was recorded in Demirdoven Dam Lake indicating low species dominance in spring. Pielou evenness (J) index value was showed its maximum value with 0.98 indicating uniformity in zooplankton community.

Community structure analysis of soil insects and their potential role as bioindicators in various ecosystem types in Lombok, West Nusa Tenggara, Indonesia

Abstract. Rohyani IS. 2020. Community structure analysis of soil insects and their potential role as bioindicators in various ecosystem types in Lombok, West Nusa Tenggara, Indonesia. Biodiversitas 21: 4221-4227. Various types of ecosystems can be found in Lombok, with the dominant ecosystems are natural forest, mangrove, mixed garden, rice field, and mining. These ecosystems have a high level of biodiversity and unique flora and fauna communities, including soil insects that partake in the process of ecosystem energy flow. This study aimed to analyze the community structure of soil insects and their potential role as bioindicators in five types of dominant and unique ecosystems in Lombok island. The data collection was done using pitfall traps, yellow pan traps, baited pitfall traps, soil sampling, and litter collection. The findings revealed that there are 60,439 individuals, 79 families, and 16 orders of insects in various types of ecosystems. Diversity ​​(H') and evenness (E) index values ​​for family level in all ecosystem types are low on average (H'=0.76 and E=0.10). Cerambycidae (Coleoptera), Trichogrammatidae (Hymenoptera), and Cicindelidae (Coleoptera) are a potential bioindicator in the forest, in the mangrove, and in the rice field ecosystems, respectively. However, the potential bioindicator could not be found since the distribution of the family is almost even in the garden ecosystem. The Tenebrionidae (Coleoptera) and the Acroceridae (Diptera) are soil insects with relatively high abundance and are found only in the mining ecosystems.

Spatial variation in assemblages of Odonata (Insecta) within habitat gradients in large, pristine peat bogs in Belarus

The variation in environmental conditions in peat bogs can be expressed by odonate assemblage composition among habitats or by differences in species richness, abundance and diversity among study sites in a regional context. The adult Odonata of large, pristine peat bogs in Belarus were examined. Adult Odonata were counted along fixed transects in main peat bog habitats under favorable weather conditions. The odonate diversity showed clear differences, affected by distance to the water body, wind speed, and bog water level. The highest diversity was recorded along lakeshores. This study detected distinct odonate assemblage variations among habitats such as lagg zones, lakeshores and hollows. The large areas occupied by pine bogs and open bogs had a very similar species composition and lower diversity. On the other hand, the Shannon diversity index (H′ = 1.433–2.295) and Pielou’s evenness index (J’ = 0.468–0.507) values were relatively high compared to those of terrestrial insects. The main differences among adult odonate assemblages were driven by cold-adapted, highly specialized species such as Leucorrhinia albifrons, Leucorrhinia dubia, Sympetrum danae and two abundant generalist species such as Sympetrum sanguineum and Sympetrum vulgatum. Peat bog specialists are among the most rapidly declining insects and, therefore, relatively intact Belarusian peat bogs are refuges for many threatened species and have considerable conservation potential.

Diversity Index of Insect Species on Sorghum Plantations in Kolam Village, Percut Sei Tuan District, Deli Serdang

This research aimed to know the diversity of insects of sorghum plantations and the status of insect functions in sorghum plants. The purposive sampling method were done, which used 4 traps, consist of yellow sticky trap, sweep net, pitfall trap and light trap for 8 observations research were done from May to September 2019 at Kolam Village, Percut Sei Tuan District of Deli Serdang Regency, then continue to identified in Pest Laboratory Faculty of Agriculture University of Sumatera Utara, Medan. The results showed that there were 117 individuals insects which consist of 10 orders and 33 families. The highest relative density was 14.74% and the lowest was 0.42% sere recorded, while the highest relative frequency was 4.08% and the lowest was 1.53%. The value of insect diversity index was 3.115 (High), it is mean the diversities of insects varied and the habitat was good for growth of insects. The value of evenness index was 0.891 (high) and richness index was 4.15 (high). The dominant insects recorded from Order of Hymenoptera (Family of Formicidae), continued to Coleoptera (Family of Scarabaeidae; Coccinellidae) are quite diverse in the sorghum plantations. The function status of insects was recorded as herbivores, parasitoids, predators, pollinators and decomposer were determined.

Floristic composition and distribution pattern of herbaceous plant diversity in fallow lands of the central districts of Punjab, India

This study explores the change in composition of herbaceous plants with change in season and site in the fallow lands of central districts of Punjab, India. Overall 41 plant species were reported from studied sites. Poaceae and Asteraceae were recorded as dominant families with seven and six plant species, respectively. Density and IVI values of perennial plant species were recorded to be the maximum from July to September and for annuals maximum values were from February to March and from July to September. Diversity indices like Shannon Wiener index, evenness index, Menhinick index, and Simpson diversity index values showed variation with season and site. Similarity index value between studied sites was recorded to be the minimum in July (0.45) which indicates a maximum value of dissimilarity index in this month. The information generated in this study can be exploited by researchers for conservation of natural plant diversity and timely assessments of such areas help to study climate change.
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KEANEKARAGAMAN JENIS IKAN FAMILI CYPRINIDAE DI SUNGAI ARIUNG KECAMATAN PUTUSSIBAU UTARA KABUPATEN KAPUAS HULU

The cyprinidae family is a true freshwater fish that dominant in Indonesian fresh waters and the main in habitant of the most population in several rivers in Kalimantan. One of river that found cyprinidae family is Ariung river in Mendalam Village, North Putussibau District, Kapuas Hulu Regency, West Kalimantan. This study aims to obtain data on the fish diversity of the cyprinidae in Ariung River. The method used in this research is survey method and direct observation in the field. Determination of sampling points with purposive sampling and followed systematically based on environmental conditions. The results showed as many as 5 observation stations found 187 individuals belonging to 15 types, among them are Barbichthys laevis, Barbodes schwanenfeldii, Cyclocheilichtys apogon, Hampala macrolepidota, Labiobarbus ocellatus, Osteochilus hasselti, Osteochilus kappenii, Osteochilus microcephalus, Osteochilus pleurotaenia, Osteochilus waandersii, Puntioplites bulu, Rasbora caudimaculata, Rasbora sp, Thynnichthys polylepis dan Thynnichthys thynnoides. Based on the results of data analysis, the dominant index of fish in the Ariung river shows low dominance. Values (C) from the five observation stations ranged from 0.135 - 0.284. The index of fish species diversity in the Ariung river shows moderate species diversity. Diversity index (H ') values for the five stations ranged from 1.322 - 2.130. Evenness index (E) values at the five stations are at 0.912 – 0.953 and a wealth index (R) at the five stations has a high wealth of R > 4.Keywords: Ariung Rivers, Cyprinidae Family, Fish Diversity

Abundance of Macrozoobenthos in the Seagrass Field Ecosystem in Cemara Besar Island, Karimunjawa Islands

Seagrass has several important ecological functions which protected some species of invertebrates such as crustaceans, bivalves, gastropods, echinoderms, and other marine organism. Seagrass have ecological processes, where any interaction of several biotic and environment components. One of the biotic components associated with seagrass is macrozoobenthos. This study aims to determine the type and abundance of macrozoobenthos, the value of ecological index and covering percentage of seagrass at Cemara Besar Island, Karimunjawa. This study was conducted at Cemara Besar Island, Karimunjawa. The method used in this study was survey method with descriptive data analysis. Measurement of seagrass and macrozoobenthos using transect quadrant size of 1 x 1 meter. Macrozoobenthos living on the surface susbtrat (epifauna) was taken directly, while macrozoobenthos living within the substrate (infauna) using a corer was inserted into the substrate to a depth of 25cm. After conducting the samples were treated, the sediment sample sieved using benthos filter with a pore diameter of 1 mm and put macrozoobenthos into a sample bottle which has been given a 4% formalin solution and dye rose bengal, then identification of macrozoobenthos using a microscope and magnifying glass. Macrozoobenthos samples were analyzed using the calculation of abundance, the diversity index, the evenness index and the domination index. The result show that, in seagrass ecosystems in Cemara Besar Island Karimunjawa was found 4 classes macrozoobenthos consisting of Bivalve 3 species, Polychaeta 5 speseies, Echinoidea 4 species, and Gastropoda 25 species. The value of abundance in marine protection zone ranging from 6.32 to 8.42 ind/dm3 and the value of abundance in utilization zone marine ranging from 6.85 to 7.37 ind/dm3. The value of diversity index in the marine protection zone ranging from 1.42 to 2.57 are included in the category of low to moderate, while in the Marine Utility Zone ranging from 3.26 to 3.47 are included in the high category. The value of evenness index in the marine protection zone (E = 0.61 to 0.74) and utility zone (E = 0.77 to 0.82) were included in the high category (E > 0.6) in the second zone. The value of domination index in the marine protection zone (C = 0.20 - 0.48) and utility zone (C = 0.13 - 0.17) indicates that there are not macrozoobenthos species dominates. The Percentage cover of seagrass in marine protection zone from 68.75 to 76.04%, while the percentage cover of seagrass in utility zone ranging from 59.38 to 65.63%.

Makrozoobentos Diversity in Various Substrates Type in Way Sindalapai River, Liwa Botanical Garden

The study of macrozoobenthos diversity in Way Sindalapai River can be used as one of the basic concepts in sustainable resource management in Liwa Botanical Garden area. Macrozoobenthos has an important role in the aquatic ecosystem, such as a food source for aquatic biota and as a detritivore. This study aims to determine the diversity of macrozoobenthos based on different sediment substrates in Way Sindalapai River, Liwa Botanical Garden, West Lampung. This study uses a purposive sampling method based on differences in the sediment substrates: muddy, sandy, rocky, and scrub with 3 replications. Sampling was carried out using a stratified filter and tweezers to separate the organism from the substrate. Samples were preserved in 70% alcohol and were identified by identification books at the Ecology Laboratory, FMIPA Universitas Lampung. The results of the study found 10 macrozoobenthos orders with a total of 155 individuals included in 13 families. The results of the calculation of diversity index values (H ') macrozoobenthos for all types of 2.26 (medium category). The highest macrozoobenthos dominance index (D) of the four substrates is in the rocky substrate that is 0.41 (low category). While the evenness index value (E) of macrozoobenthos in the Sindalapai Way River was 0.44 (medium category).

KEANEKARAGAMAN KEPITING BIOLA PADA KAWASAN HUTAN MANGROVE DESA KARIMUNTING KECAMATAN SUNGAI RAYA KEPULAUAN KABUPATEN BENGKAYANG

Karimunting Village is a coastal area that has a mangrove with contained several faunas in it, one of which is a fiddler crab. The fiddler crab is a Decapoda ordo and it is included in the Ocypodidae family. This study aims to collect data on the diversity of fiddler crabs in Karimunting Village. The method used in this study is a survey, while the sample is collected by applying the transect line with a purposive sampling technique. The transect line is 500 m length, with a total of three lanes. There are ten plots of 1x1 meter in size in each transect lines to pick up fiddler crabs. Fiddler crabs species were found in 6 species, namely Uca paradussumieri, Uca annulipes, Uca forcipata, Uca rosea, Uca crassipes and Uca tetragonon. The Shannon-Winner species diversity index (H') of fiddler crabs in 1st and 2nd lanes both are categorized medium, while in the 3rd lane is categorized low. The range of values H'=0,3-1,5. The value of species abundance index (Xi) ranges from 3-16.6 ind/m2. The value of evenness index (e) ranges from 0,72 to 0,84. The dominance index value (C) ranges from 0,3 to 0,5 categorized as the absence of the dominant species of fiddler crab. Comparison of species similarity index (IS) for each lane is categorized differently, for the 1st and 2nd lane the index is 91% and categorized as having high species similarity, then in 2nd and 3rd lane the index is 75% and categorized as having a medium species similarity, whereas the index for 1st and 3rd is 60%, therefore it is categorized as having low species similarity.Keyword: Diversity, Fiddler Crab, Karimunting Village

Multivariate analysis of phytoplankton community structure in Changli Gold Coast National Nature Reserve of Hebei Province in Spring, 2019

In order to research the characteristics of phytoplankton community structure in Changli Gold Coast National Nature Reserve, China, 14 survey stations were set up in this area in May 2019. The basic characteristics of phytoplankton community composition, cell abundance and community diversity were analyzed, and the Multi-Dimensional Scaling (MDS) was used to divide the structure of phytoplankton community. The results showed that a total of 30 species of phytoplankton were identified in this area, mainly diatoms, and the main ecological types were temperate inshore wide temperature and wide salt species. The average cell abundance of phytoplankton in May was 54.38×104 cells/m3, and the main dominant species were Nitzschia sp., Skeletonema costatum and Noctiluca scientillans. The average value of Shannon-Wiener index was 2.26, The average value of evenness index was 0.75. The average of richness index was 0.73. The phytoplankton divided into 6 zones with significant differences by CLUSTER Analysis (P<0.001).

Richness, Diversity And Evenness Of Birds In Small Island

Birds play an important role as bioindicators of climate change. For this reason, it is important to know the species richness, diversity and evenness of birds found on small islands. The location of the study was in Haruku Island Maluku. Bird data collected included all bird species, taking into account certain bird species that are sensitive to environmental changes. Bird data collected by the Line Transect method is to use work lines on rectangular data plots in the specified location. This method was chosen because it can trace the plot area of data in a short time and allow repetition of data collection in one day according to the desired time. This method of analysis is to determine the level of diversity in the form of diversity indices, then to scale up the species abundance and then to calculate the estimated population density. The results of the study found 23 species of birds. There were 2 large families recorded, namely: Family Columbidae of 4 types, and Family Psittacidae as many as 5 types, while the other Family groups only had 2 or 1 types.The overall value of the bird species wealth index in 5 data transects is MEDIUM with the value of the Type Wealth Index 3.975863. Then the five Diversity Index of data transects is Medium with the Diversity Index value 2.710911452. Furthermore, the evenness index on five data transects has a fairly good value, which is included in the High Equity Index category with the Evenness Index value of 0.864588 which approaches the number one. From the analysis simulation results, it was found that the temperature aspect, in this case the temperature range at the study location when the data collection did not affect the number of bird species at all, while the estimated altitude aspect has the potential to influence the bird species encounter rate. This condition is quite reasonable because if we look at the data on the number of bird species collected on different transects of data placed in different segment elevations, there seems to be a tendency to increase altitude, so the number of species recorded tends to decrease.

Butterfly as bioindicator for development of conservation areas in Bukit Reban Kambing, Bukit Belading and Bukit Tukau, Johor, Malaysia

Abstract. Ismail N, Rahman A A A, Mohamed M, Abu Bakar M F, Tokiman L. 2020. Butterfly as bioindicator for development of conservation areas in Bukit Reban Kambing, Bukit Belading and Bukit Tukau, Johor, Malaysia. Biodiversitas 21: 334-344. Butterflies are often used as indicator surrogates to evaluate the quality of ecosystems. This is made possible due to their sensitive responses toward environmental fluctuations and habitat changes. Butterflies were collected opportunistically using aerial nets at three hill dipterocarp forests; Bukit Reban Kambing (BRK), Bukit Belading (BB) and Bukit Tukau (BT) of Johor, Malaysia from 8th to 11th March 2016. The objectives of this study are to provide a checklist of butterflies of the hills and evaluate habitat suitability in an effort to support the proposal to gazette the hills as part of the Gunung Ledang protected area. A total of 60 individuals belonging to 23 species, 21 genera, and five families were recorded. Comparing the three hills, BRK recorded the greatest individual and species numbers, followed by BT and BB. BRK recorded the highest Shannon diversity index, H’ (2.272) value, whereas BB presented the highest value of species evenness index, E’ (0.945). MaxEnt modeling of the butterflies in BRK, BB, and BT showed a network of high habitat suitability areas connecting Gunung Ledang and our sampling locations. Despite limited sampling effort, this baseline data could possibly strengthen the effort for gazettement and prevent further pressure from mining activity and land conversion.

Marmara Denizi biyoçeşitliliği ve Derinsu pembe karidesi av miktarı

In this study indicated that biodiversity and catch composition of the beam trawl shrimp fishery in the Sea of Marmara. Sampling was carried out between October 2011 and February 2014 with beam trawler vessel operating in the Marmara Sea as seasonal. The Sea of Marmara were examined in 6 regions: Erdek, Tekirdag, Marmara Island, Kapidag and Yalova. In total, the catch consisted of 91 species belonging to 6 groups of marine fauna, including Osteichthyes (42 species), Chondrichthyes (7), Crustacea (12) Bivalvia (8), Cephalopoda (5), Echinodermata (10) and other invertebrates (7). Margalef species richness index (d), Shannon diversity index (H’), Pielou’s evenness index were calculated. Cruscal valis similarity diagrams were drawn by seasonal, regional and depth. According to seasons maximum species richness, diversity and evenness index values were in the winter periods. According to the regions maximum species richness, diversity and evenness index values were in the 1. (Erdek) and 4. (Kapidag) regions and minimum values of the indexes were in the 6. (Silivri) region. And the Cruscal valis similarity diagram shows % 57 similarity between the regions.

Diversity of coral reef fish in the coastal water of Spelman Straits, Southeast Sulawesi

Spelman Strait is one of the potential reef fisheries. This study aims to examine the potential of reef fisheries in the Spelman Strait. The data used in this study are primary data to determine the abundance of reef fish and the use of PaST (Paleontological Statistics) tools to assess diversity, Evenness, wealth, and dominance indices. The results showed that live coral cover from all observation stations was 37.71%. The abundance of reef fish has been under pressure, the diversity index still has good but some families experience threats, the Evenness index value also still shows an even distribution but there are several families threatened, the wealth index still describes good species wealth, but the distribution is uneven, while the dominance index value illustrates that the condition of the coral reef ecosystem is under pressure. This condition is caused by destructive fishing so that the existence of some economically important targeted fish is threatened.

Tree Diversity, Stand Structure, and Community Composition in an Island Forest of Pulau Perhentian Besar, Terengganu

The Perhentian Island Archipelago comprising of 11 small islands is located in the state of Terengganu are among the biodiversity rich localities in Peninsular Malaysia. Perhentian Besar with approximately 867 hectares is one of the inhabited island and become the centre of tourism besides Perhentian Kecil. Island is well known as a place for many endemic and endangered living organism as previously demonstrated on other similar forested islands in Southeast Asia. However, there is little attention and effort of protection has been received by the terrestrial ecosystems that reside nearby the coastal. Thus, the present study investigates on tree diversity, stand structure and community composition in the island of Perhentian Besar, Terengganu. Forest plot of 0.5 hectare was established to analyze the floristic composition of tree taxa. The plot was divided into 10 subplots of 25m x 20m. All trees with 5cm diameter breast height (dbh) and above were tagged, measured for dbh size, recorded and identified. Voucher specimens were taken for further verification purposes. A total of 102 tree species were recorded comprising of 28 families and 65 genera. Rubiaceae had the highest number of species (11 species) and with regards to relative dominance, Shorea leprosula (Dipterocarpaceae) gave the highest importance value index (IVi) for species with a value of 8.45%. The Shannon-Weiner Diversity Index (H’) was considered high in the present study with 3.94 (H’max = 4.62) and the Evenness Index (E) value of 0.85 indicated that all species in the present study are almost equally abundant. The forest stand structure had a reverse J-shaped curve for tree size-class distributions as frequently observed in many natural forests, which indicated that the forest stand in the study site had a good recruitment patterns and also a main feature of matured forest in Peninsular Malaysia. The present study will help us to understand the pattern of tree species composition, diversity and forest ecosystem dynamic in Pulau Perhentian Besar.

The Dominance of Tramps Ants in The Settlement Area of Semarang, Central Java

The high rate of urbanization in Semarang have caused the land conversion from forest into various human need spaces. The land conversion is not only affect the life of humans but also the animals, including ants. The objectives of this study were to examine the dominance of tramp ants in the settlement area of Semarang City. The method used was the bait trap method using chicken intestine as a bait. Samples of ants were collected from four habitats, i.e., waste disposal area, traditional markets, house area, and urban parks. This study found four dominant ants, i.e., Anoplolepis gracilipes, Paratrechina longicornis, Solenopsis geminata and Monomorium pharaonis. Two of them were categorized as tramp ants (Anoplolepis gracillipes and Paratrechina longicornis). The highest diversity of ants was found in house (H'= 2.72). The waste area tends to be an ideal habitat for particular species, which was proved by the low value of Simpson's dominance index (iD = 0.06) and a high value of evenness index (E=0 0.89). This study provides new information about tramp ants population as pest in urban area. The findings would be beneficial for controlling the population of tramp ants, which are disturbing humans in the settlement area.

Variations in bacterial community during bioclogging in Managed Aquifer Recharge (MAR): A laboratory study

Understanding evolution of bacterial community diversity, composition, and structure is of great importance for targeted prophylaxis and treatment of bioclogging of reclaimed water after Managed Aquifer Recharge (MAR). Based on laboratory percolation experiments, temporal variations in bacterial 16S rRNA gene copy number and community diversity, composition, and structure were investigated using real-time quantitative polymerase chain reaction (qPCR) and high-throughput sequencing in this study. During the percolation experiments, the relative saturated hydraulic conductivity (Ks') decreased from 1.0 to 0.011 at 588.3 h, indicating that a complete clogging occurred in the sand columns. Correspondingly, the bacterial 16S rRNA gene copy numbers reached a maximum of 3.9 × 109 copies per gram of sand at 180.5 h, and then decreased to 6.2 × 108 copies per gram of sand at the end of the test. Four microbial samples were collected in situ from the reclaimed water (SRW), and the clogged sand columns, namely SK0.52, SK0.08 and SK0.011, of which the Ks’ values decreased to 0.52, 0.08 and 0.011, respectively. The Chao richness index values of the bacterial community were 352, 207, 205, and 197 for SRW, SK0.52, SK0.08, and SK0.011, respectively, revealing lower species richness in the sand columns. The Shannon index values were 3.27, 2.84, 3.51, and 3.21 for SRW, SK0.52, SK0.08, and SK0.011, respectively. Meanwhile, the Evenness index values were 0.56, 0.54, 0.67, and 0.61 for the four samples in turn. This result implied that the changes in bacterial diversity and evenness were not obvious. The principal coordinate analysis (PCoA) results showed major differences in bacterial community composition between the four samples. A variety of bacterial phyla were found, among which Proteobacteria were predominant. For the non-Proteobacterial phyla, Parcubacteria, Acidobacteria, Chlamydiae, Gracilibacteria, Chloroflexi, and Saccharibacteria disappeared when moving from the raw reclaimed water to the solid porous media. Instead, Bacteroidetes and Actinobacteria were detected in the sand samples. Although some differences existed, a core group of bacteria persisted and might play a critical role during MAR bioclogging.