Periphyton Samples Research Articles

Ciliates as bioindicators of environmental pressure in a karstic river

Ciliates (protozoa) are a very large and diverse group of microeukaryotes that occupy a central position in the trophic web of freshwater ecosystems. Ciliates exhibit high ecological sensitivity and have tremendous bioindicator potential, but they are largely ignored in routine biomonitoring, mainly due to limitations in morphological diagnosis, which is both time-consuming and costly. In this study, we combined molecular (Illumina sequencing of the hypervariable V9 region of the SSU rRNA gene) and morphological approaches to get a detailed insight into the periphytic ciliate community structure and function within a karst, tufa-precipitating hydrosystem (National Park Krka, Croatia). Periphyton (biofilm) was sampled from light- and dark-exposed lithified tufa/stones at four representative locations within the Krka River, including upstream, midstream, and downstream river sections. We identified hydrological parameters and saprobiological classification of the sampling locations as the main structuring factors for ciliate communities. The molecular approach showed a clear separation of sampling locations in beta diversity analyses, as confirmed by PERMANOVA test. In contrast, alpha diversity was mostly affected by light exposition of the lithified tufa/stones, as confirmed by morphological approach. Environmental conditions consistently affected ciliate community composition at all locations, resulting in clear separation of periphyton samples. Our results indicate that ciliates should be considered as important bioindicators in monitoring tufa-forming rivers and streams, and the molecular approach (V9 region) proved to be applicable because as it efficiently captured the diversity of ciliates in periphyton. Validation of such an approach would lead to significant progress in extending monitoring to a broader range of indicator organisms than those now included in standard monitoring.

Ciliates (Alveolata, Ciliophora) as bioindicators of environmental pressure: A karstic river case

Ciliates are single celled eukaryotes recognized as key players in the microbial loop of aquatic ecosystems. The present study was carried out on the Krka River (Croatia), a karst freshwater ecosystem characterized by tufa barriers, biomineralization and highly diverse aquatic communities. The main aims of the study were to investigate ciliate community structure in the biofilm (i.e. periphyton) samples collected from light- and dark-exposed lithified tufa/stones. Furthermore, by establishing links between ciliate community patterns and environmental parameters, we aimed to assess the bioindicator potential of specific ciliate taxa for environmental monitoring of freshwater habitats. The periphyton sampling was performed at four representative sites of the river source, upstream, middle and downstream river sections. Ciliate community was investigated via traditional microscopy analyses and environmental DNA (eDNA) metabarcoding (Illumina sequencing of the hypervariable V9-region of the SSU rRNA gene). The molecular approach recorded a substantially higher number of ciliate taxa, most of which taxonomically belonging to genera typically occurring in tufa barriers. The results from microscopy analyses did not show any links between ciliate community structure and sampling location. However, eDNA approach indicated significant differences among the sampling locations regarding the ciliate community structure. Thereby, hydrological parameters and saprobiological classification of the sampling sites were the main structuring factors for ciliate community. The coupling of eDNA metabarcoding with the morphological approach provides a robust, in-depth analytical system in elucidating the bioindicator potential of ciliated protists.

Influence of temporal changes on a diatom species in a floodplain lake: paleolimnological and biomonitoring approach

Long term anthropogenic and natural impacts may result in effects on hydrological and environmental variables in aquatic ecosystems, as floodplain lakes, causing changes in diatom populations and community composition. We hypothesized that temporal abiotic factors over time favoured the establishment and increase in relative abundance of the Achnanthidium minutissimum complex. For a greater understanding of variation in species abundance, we used biomonitoring and paleolimnological data, combining 18 years of data from periphyton samples and more than 60 years from sediment samples. To test the relationships between the environmental parameters and relative abundance of A. minutissimum from biomonitoring data, we used generalized linear models (GLM). Based on GLM, the relative abundance of A. minutissimum increased with lower water depth, lower temperature, higher turbidity, and high pH. These conditions coincide with periods of drought in the floodplain, which were more frequent and longer after the construction of dams near Lake Garças. Additionally, the paleolimnological data suggest that climatic and anthropogenic influences on abiotic factors, such as water level and turbidity may have been responsible for the increased abundance of A. minutissimum in Lake Garças, as well as its dominance in the periphytic community from 2000, after the last dam construction near the lake. This shows how the modification of an aquatic environment can change diatom populations, and highlights the importance of combining historical information, paleolimnological analyses and biomonitoring data to understand population and ecosystem processes over time.

Evaluating the periphyton as a bioreactor for removal of nutrients in a shallow hypereutrophic reservoir

Abstract: Aim We evaluated the periphyton on artificial substrate in the treated sewage effluent, effluent patch, inside and after the macrophyte stand in a shallow hypereutrophic reservoir. Specifically, we investigated the relationship between N and P contents and algal biomass in the periphyton with N and P availability, focusing on nutrient retention. Methods Periphyton sampling was performed at the effluent inlet, effluent path, inside, and two sites after macrophyte stand. Periphyton sampling was performed after 30 days of colonization. Abiotic variables were determined in the sewage effluent and in the reservoir water. Results Biomass and N and P contents in the periphyton were significantly different among sampling sites. The highest nutrient concentrations were found in the sampling sites with effluent. The highest periphyton chlorophyll-a were found inside and after the macrophyte stand, while N and P contents were the highest in the effluent inlet and effluent. Conclusions In conclusion, N and P contents in the periphyton were associated with N and P availability, evidencing the ability of nutrient retention of the community. Our findings suggest that periphyton on artificial substrate can as a potential tool for removing N and P from the effluent from the sewage treatment system, contributing to minimizing the nutrient load discharged in a shallow reservoir.

The role of macrozoobenthos and periphyton in bioindication of water resources quality in Uzbekistan

The material was collected during the open water period from March to the end of November 2019. In the period of our research in the basin of the Chirchik river (Boshkizylsay river, Ugam river (pre-settlement site), Chirchik river) were discovered several types of zoobenthos and periphyton. The monitoring was carried out on 8 stations, in total of 64 quantitative samples of macrozoobenthos and periphyton were taken. Anthropogenic pollution causes changes in the composition and structure of aquatic communities, expressed in the change of dominant complexes of organisms, the simplification of the ecological structure, the appearance of highly saprobic species in the composition of the dominants.

Analisis Kelimpahan Dan Keanekaragaman Perifiton Rawa Bangkau Kabupaten Hulu Sungai Selatan Kalimantan Selatan

Periphyton group are biota communities that be able adapt and grow well in lentic waters. Their habits are adhere to a permanent location. Aquatic vegetation in Bangkau can influenced the periphyton abundance and diversity as natural food in the food chain. The purpose of this study was to analyzed abundance and diversity of Periphyton from different aquatic vegetation. The research was conducted in three stations by purposive sampling. The method used was quantitative explored. The data that has been taken were epiphythic periphyton samples. Periphyton sampling procedures, preservation, and analysis were carried out based on Indonesian National Standard methods. Bangkau’s peatland had the highest abundance of phytoplankton-periphyton (9982 sel/liter) in inlet, but low at middle station (778 sel/liter). Zooplankton-periphyton (553 sel/liter) in middle station was the highest abundance whereas in outlet station (153 sel/liter) was the lowest. Bacillariophyceae had predominant and always attendanced Oscillatoria, Closterium, Planktonella, Diatom, meanwhile zooplankton-periphyton dominated Ciliophora in all stations and sampling. Diversity index of phytoplankton-periphyton in inlet station (1,55) was the highest and in inlet (0,77) was the lowest. Zooplankton-periphyton in middle (1,76) and outlet (0,94) was different based on Shannon wiener’s Index. The abundance index of Bangkau were mesotrophic categorized for phytoplankton-periphyton and oligotrophic for zooplankton-periphyton. Due to the low level of species diversity (H’≤ 3) showed moderate stability and for the water quality conditions was moderate polluted.

Using diatoms to assess river restoration: A pilot study in Whychus Creek, Oregon, USA

AbstractA primary goal of river restoration is to reestablish lost ecological functions. Yet the impact of restoration on diatom assemblages and algal biomass in a stream is rarely addressed in the scientific literature reporting the outcomes of restoration projects aimed at improving riverine habitat. To investigate the potential for using benthic diatoms as indicators of the benefits to habitat associated with river restoration, we conducted a pilot diatom study in Whychus Creek, a headwater tributary of the Deschutes River in Oregon, USA. As part of a work study project for college students, we collected periphyton samples in a restored reach, a restored transition reach and an unrestored reach (control) and compared diatom assemblages and algae biomass of these reaches. Diatom assemblages and traits differed substantially between the control and restored reaches and the median percentage of chlorophyll a in the periphyton biomass increased from 9% in the control reach to 12% in the restored reach. The results of this pilot study suggest that benthic diatom assemblage may be useful indicators of river restoration success, particularly for approaches that aim to reconfigure channels and increase floodplain connectivity and habitat complexity.

Increasing anthropogenic salinisation leads to declines in community diversity, functional diversity and trophic links in mountain streams

Anthropogenic salinisation is becoming an increasing global issue for freshwater ecosystems, leading to serious biodiversity loss and ecosystem degradation. While the effect of anthropogenic salinisation on freshwater ecosystems has been intensively studied in recent years, most studies focus on salinisation effects on the individual or single groups of organisms without considering the effect on the ecosystem levels, such as diversity and trophic links. Therefore, we conducted a long-term field survey from May 2009 to August 2016 at 405 sites in northeast China to investigate the effect of a gradient of salinisation on community diversity, functional diversity and trophic links in mountain streams. Samples of water chemistry, periphyton, macroinvertebrates and fish were collected. Our results showed that as anthropogenic salinisation increased, Ca2+, Mg2+, HCO3− and SO42− exhibited significant increases (p < 0.05). These increased ions caused decreases in taxonomic evenness and biotic integrity, but an increase in the beta diversity for periphyton and macroinvertebrates, and a slight increase in the evenness of fish. The increased salinisation resulted in the extirpation of salt-sensitive taxa and declines in macroinvertebrate functional richness and functional redundancy, which consequently led to simplified trophic links. Our results implied that if salt-tolerant taxa in high salinisation sites were not functionally redundant with less tolerant taxa, alterations of their functional composition probably decrease the stability of ecosystem functions. Overall, our study suggests that the ongoing anthropogenic salinisation is posing serious threats to biodiversity and trophic links in river ecosystems, and should be considered in future river restoration and biodiversity conservation.

Assessment of the ecological health of Geumchon stream using fish, benthic macroinvertebrate, and periphyton

An urban stream is currently being reconstructed as an ecological stream in Paju City, Korea. The diversity of fish, benthic macroinvertebrates, and periphyton in Geumchon stream was investigated, and the condition of the ecological health was assessed using the physicochemical condition of the water system. The goal is to use the data from this investigation to contribute to the establishment of policy for the conservation of Korea’s water environment. Samples of fish, benthic macroinvertebrates, and periphyton were collected from three sampling sites along the river a total of five times during the period October 2015 to June 2018 to determine the ecological structure of the Geumchon stream and its need for restoration. Samples of water and sediment were collected five times from five sampling sites for analysis of the physiochemical properties of the stream. Four families and ten species of fish were found with a total of 339 individuals. The fish found in the stream included the Carassius auratus, the Pseudorasbora parva, and the Oryzias sinensis, most of which are tolerant of water pollution. The relative richness index for Carassius auratus, Oryzias sinensis, Hemiculter eigenmanni, and Pseudorasbora parva was 52.5, 16.5, 12.7, and 12.4%, respectively. The predominant benthic macroinvertebrates observed at most sites were the Chironomidae sp. The dominant periphyton from 2015 to 2017 was the Nitzschia palea and in 2018 the Oscillatoria sp. Using the benthic macroinvertebrates index (BMI), the fish assessment index (FAI) and the trophic diatom index (TDI), the environmental condition ranged from moderate (C grade) to bad (D grade). The predominant species caught reflect the turbulent condition of the urban stream due to its reconstruction and the pollution. The biological indices (BMI, FAI, and TDI) and the physicochemical water items (BOD) were assessed separately to identify the quality of the water in the stream. The application of these biological assessments together with the chemical properties of the water can be used to provide a composite picture of the ecological health of a water system and to identify disturbances to its current condition.

Metal(loid) contamination in water, sediment, epilithic periphyton and fish in three interconnected ecosystems and health risk assessment through intake of fish cooked in Indian style.

Samples of water, sediment and epilithic periphyton (EP) were collected from a lake (Dimna, DL), an intermediate canal (IC), and a river (Subarnarekha River, SR) to compare the pollution status of an urban ecosystem, and the concentrations of metal(loid) s were determined. Water characteristics were analysed by the water quality index (WQI). Sediment pollution was assessed using the ecological risk index (ERI). Accumulation of metal(loid) s in EP was determined by using bioaccumulation factor (BAF) and biota-sediment accumulation factor (BSAF). The result showed that the DL was least polluted (WQI = 30.39) and SR (WQI = 90.13) was the most polluted ecosystem. Sediment analysis revealed that Ni, Cr and Cd are the significant pollutants, especially in SR. The THQ value for fish dishes cooked in Indian style was found higher than that of raw fish, suggesting calculations considering the cooking process can provide better results. Health risk assessment shows that people inhabiting DL are vulnerable to Cr and Cu exposure, whereas people inhabiting IC and SR are susceptible to As and Co exposure due to the consumption of cooked fish. Moreover, for a developing country like India, it is important to upgrade the assessment methods and include regular monitoring of interconnecting ecosystems for the safeguard of human and ecological health.

Depth-distribution of lake benthic diatom assemblages in relation to light availability and substrate: implications for paleolimnological studies

We analyzed the depth distributions of benthic diatoms in two adjacent, but hydrologically distinct subalpine lakes (Lakes Soiernseen, S-Germany). Lake Unterer Soiernsee is affected by marked water-level fluctuations and is light-penetrated to the bottom most of the year, while Lake Oberer Soiernsee provides more stable conditions and an extended aphotic zone. Mixed samples of epiphytic, epilithic, epipsammic and epipelic periphyton were taken in one-meter depth steps by scuba divers. Most of the common benthic diatoms occurred in distinct depth-areas. RDA analyses showed that depth was strongly correlated with species distribution in both lakes. Depth-constrained cluster analyses indicated three distinct diatom community zones in each lake. A shallow littoral zone hosting mainly epiphytic and epilithic species and a deeper littoral zone with mainly epipsammic and epipelic taxa existed in both lakes. Additionally, a highly disturbed near-shore littoral zone with diatoms adapted to unstable conditions (aerophilic taxa, pioneer species) was found in Lake Unterer Soiernsee, and a deep-water pelagic zone with mainly planktonic taxa in Lake Oberer Soiernsee. Light availability, substrate, physical stressors and nutrient concentrations were linked closely with water depth. While light availability affected the ratio of benthic and planktonic diatoms, substrate type influenced benthic diatom assemblage structures. Diatoms occurring in surficial sediments of the aphotic zone represent an ideal cross-section of the recent diatom assemblage of the lake, including benthic and planktonic species. However, sediment samples taken in light-flooded depths are inappropriate for studies based on shifts between benthic and planktonic taxa, because in situ benthic species dominate the surface-sediment assemblages, while settled tychoplanktonic and planktonic species occur less frequently. A diatom-inferred depth model was created for each lake to prove the usability for down-core studies using weighted-averaging approaches. For both lakes these models are highly appropriate to reconstruct past fluctuations in water-transparency or lake-level. With regard to the development of diatom-based TP-transfer-functions for Bavarian mountain lakes, we found it is highly important to consider lake depth and transparency. Based on the findings of this study we recommend the creation of two different training-sets, one for deep or low-transparency lakes with an aphotic zone including both benthic and planktonic diatoms, and another one for shallow, clear water lakes solely using benthic diatoms.

Distribution of Periphyton in the Upstream Section of Citarum River, West Java, Indonesia

Periphyton indeed plays an undeniably vital role as primary producers in the food web within aquatic ecosystems such as rivers. The existence of periphyton will affect the populations of the aquatic organisms at higher trophic level, thus it is interesting to be explored, especially in big rivers like Citarum. This study aimed to explore the distribution of periphyton, including its types and abundance at several stations in the upstream part of Citarum River based on the land use in the riverbanks, in the dry season of 2018. Samples were taken at nine stations, namely Gunung Wayang Springs, Outlet Cisanti at the valley of Mount Wayang, and the connecting tributaries as follows: Cihejo, Cibuni, Cirasea, Cikaro, Cisangkuy, Cikapundung, and Ciwidey. Samples of periphyton were taken from the substrate of stone, wood, plastic, and macrophytes at three sampling points of each station. Periphyton samples were then scraped off from the surface of the substrate, where the deposit would then be filtered using plankton net No.20, preserved with Lugol 1% and subsequently identified. The results showed there were 83 species from 58 genera of both phytoperiphyton and zooperiphyton, classified as periphyton found on the sites. The total abundance of phytoperiphyton ranged between 2.3 x 104 ind/m2 and 1.3 x 108 ind/m2 where the total abundance of zooperiphyton covered from 4.7 x 102 ind/m2 to 3.7 x 105 ind/m2. The highest and the lowest numbers of total abundance of periphyton were shown at stations of Gunung Wayang Spring and Cirasea tributary, respectively.

A practical device for evaluating periphyton colonization dynamics in tropical shallow wetlands

Here, we have presented a field device for sampling periphyton in lentic systems, with a tropical lowland wetland in Colombia as the model system. The periphyton sampler (PS) is composed of a central soft iron pole to which rectangular woody boxes and glass slides are attached to lateral iron axes, which can be distributed at different depths. Our PS can be used to evaluate changes in the richness and density of algal communities at different scales as well as in water quality studies.

Multiple cyanotoxin congeners produced by sub-dominant cyanobacterial taxa in riverine cyanobacterial and algal mats

Benthic cyanobacterial proliferations in rivers are have been reported with increasing frequency worldwide. In the Eel and Russian rivers of California, more than a dozen dog deaths have been attributed to cyanotoxin toxicosis since 2000. Periphyton proliferations in these rivers comprise multiple cyanobacterial taxa capable of cyanotoxin production, hence there is uncertainty regarding which taxa are producing toxins. In this study, periphyton samples dominated by the cyanobacterial genera Anabaena spp. and Microcoleus spp. and the green alga Cladophora glomerata were collected from four sites in the Eel River catchment and one site in the Russian River. Samples were analysed for potential cyanotoxin producers using polymerase chain reaction (PCR) in concert with Sanger sequencing. Cyanotoxin concentrations were measured using liquid chromatography tandem-mass spectrometry, and anatoxin quota (the amount of cyanobacterial anatoxins per toxigenic cell) determined using droplet digital PCR. Sequencing indicated Microcoleus sp. and Nodularia sp. were the putative producers of cyanobacterial anatoxins and nodularins, respectively, regardless of the dominant taxa in the mat. Anatoxin concentrations in the mat samples varied from 0.1 to 18.6 μg g-1 and were significantly different among sites (p < 0.01, Wilcoxon test); however, anatoxin quotas were less variable (< 5-fold). Dihydroanatoxin-a was generally the most abundant variant in samples comprising 38% to 71% of the total anatoxins measured. Mats dominated by the green alga C. glomerata contained both anatoxins and nodularin-R at concentrations similar to those of cyanobacteria-dominated mats. This highlights that even when cyanobacteria are not the dominant taxa in periphyton, these mats may still pose a serious health risk and indicates that more widespread monitoring of all mats in a river are necessary.

Rare diatom Stauroneis balatonis Pantocsek recorded in Lake Savsko, Serbia

Abstract Although well represented in the fossil diatom flora throughout Europe and Asia, from the early-middle Miocene to the Quaternary, Stauroneis balatonis is considered a very rare diatom with a contemporary distribution limited to two ancient lakes – Ohrid and Prespa. The objective of this study was to describe the first finding of S. balatonis in Serbia in Lake Savsko and to update information on the distribution and ecology of this rare species. Periphyton samples were collected from artificial substrates incubated at three depths (0.5 m, 0.8 m and 1.4 m) in Lake Savsko and the epilithic community was sampled in the littoral zone. Samples were collected weekly in summer 2014, from mid-July to mid-September. Diatom permanent slides were prepared and small numbers of S. balatonis specimens were observed only in samples collected in September from artificial substrates incubated at the greatest depth (1.4 m). Our results significantly contribute to the information on the contemporary distribution and the ecology of this rare diatom taxon, especially considering the fact that S. balatonis specimens were observed in our study in diatom communities developed on artificial substrates and in an urban reservoir, i.e. Lake Savsko.

Diversity and abundance of periphyton in the seagrass ecosystem Pulau Matahari, Pulau Banyak Aceh Singkil

Periphyton has a high primary productivity that enhances the primary productivity of seagrass ecosystem through food web. The objective of this study was to analyse the diversity and abundance of periphyton on seagrass leaf of Pulau Matahari, Pulau Banyak Aceh Singkil District. The research was conducted at four stations with five repetitions in August 2014. Samples of periphyton were collected by scrapping the surface of seagrass leaf with the swept area 5cm x 5cm. Samples were identified using the field of view method at Marine Biology Laboratory, Syiah Kuala University. Result of the research was found that the index values of diversity (H’) ranged from 0.85 − 1.94 (low). Abundance of periphyton ranged from 234.556 − 879.585 ind/cm2, it was found 22 species of periphyton belonged to class of Bacillariophyceae, Chlorophyceae, Rhodophyceae, Rotatoria dan Crustaceae. The highest abundance of periphyton belonged to class Bacillariophyceae (361607 ind/cm2), while the dominant species was Synedra sp. (55%).

Impact of Water Pollution on Trophic Transfer of Fatty Acids in Fish, Microalgae, and Zoobenthos in the Food Web of a Freshwater Ecosystem.

This research work was carried out to determine the effects of water contamination on the fatty acid (FA) profile of periphyton, zoobenthos, two Chinese carps and a common carp (Hypophthalmichthys molitrix, Ctenopharygodon idella and Cyprinus carpio), captured from highly polluted (HP), less polluted (LP), and non-polluted (NP) sites of the Indus river. We found that the concentration of heavy metals in the river water from the polluted locations exceeded the permissible limits suggested by the World Health Organization (WHO) and the US Environmental Protection Agency (EPA). Fatty acid profiles in periphyton, zoobenthos, H. molitrix, C. idella, and C. carpio in the food web of river ecosystems with different pollution levels were assessed. Lauric acid and arachidic acids were not detected in the biomass of periphyton and zoobenthos from HP and LP sites compared to NP sites. Alpha-linolenic acid (ALA), eicosadienoic acid and docosapentaenoic acid were not recorded in the biomass samples of periphyton and zoobenthos in both HP and LP sites. Caprylic acid, lauric acid, and arachidic acid were not found in H. molitrix, C. idella, and C. carpio captured from HP. In this study, 6 and 9 omega series FAs were identified in the muscle samples of H. molitrix, C. idella and C. carpio captured from HP and LP sites compared to NP sites, respectively. Less polyunsaturated fatty acids were observed in the muscle samples of H. molitrix, C. idella, and C. carpio collected from HP than from LP. The heavy metals showed significant negative correlations with the total FAs in periphyton, zoobenthos, and fish samples.

Cyanobacteria as regulators of methylmercury production in periphyton

Biotic mercury (Hg) methylation appears to depend on factors such as microbial activity and the concentration and bioavailability of Hg2+ to the Hg-methylating organisms. Recently, the presence of cyanobacteria has been linked with high methylmercury (MeHg) concentrations. The aim of this work was to test MeHg production in microcosms, in relation to the amount of periphytic cyanobacteria, dissolved organic matter (DOM) and phosphorus concentrations, as well as periphytic primary production rates. Water and periphyton samples were collected for cultivation and isolation of cyanobacteria from the Guaporé River floodplain, Brazil. We cultivated the periphyton in microcosms with different concentrations of cyanobacteria, total phosphorus and DOM. The highest net MeHg production (6.8 to 24.6% of added Hg d−1) occurred in the microcosm with added cyanobacteria, followed by microcosms with added phosphorus (6.1 to 11.4%) and added DOM (6.4 to 9.1%). Positive correlations were found between MeHg production, addition of cyanobacteria, phosphorus and DOM and periphytic primary productivity. Our results bring the first direct experimental evidence of the relevance of cyanobacteria and primary production as regulators of MeHg production in periphyton. These findings have numerous implications for the management of natural and engineered wetlands.

Periphython Epilithic Community Structure in Cikamal Estuary and Cirengganis Estuary, Pananjung Pangandaran, West Java

Nailah S, Rosada KK. 2018. Periphython Epilithic Community Structure in Cikamal Estuary and Cirengganis Estuary,Pananjung Pangandaran, West Java. Pros Sem Nas Masy Biodiv Indon 4: 236-241. Periphyton is one of the biotic communities that canlive well in the waters. Epilithic periphyton is cosmopolitan and allows standardization for spatial or temporal comparisons, therefore itis often used to determine the quality status of a water. The purpose of this research is to know the structure of epilithic periphytoncommunity in Estuary of Cikamal River and Estuary of Cirengganis River Pananjung Pangandaran. The method used is exploration. Ineach study site, samples of periphyton and water were taken. At the time of sampling, physicochemical parameters measured weretemperature, brightness, depth, light intensity, salinity, current velocity, pH, and DO. The results showed that the periphyton in bothestuaries consisted of phytoplankton, zooplankton, and microbenthos. In general, the abundance of phytoplankton is higher compared tothe other two groups. Periphyton in Estuary of Cikamal River found 19 species of phytoplankton, one type of zooplankton, and one typeof microbenthos, while in Estuary of Cirengganis River found 24 types of phytoplankton, nine types of zooplankton, and three types ofmicrobenthos. Periphyton density at Estuary of Cirengganis River is higher than periphyton at Estuary of Cikamal River. The higherdiversity of periphyton species is found in Estuary of Cirengganis River. The periphyton at the Estuary of Cirengganis River has ahigher evenness than the periphyton at the Estuary of Cikamal River. One species that dominates on both estuaries is Navicula sp. Basedon the Sorensen similarity index, both estuaries have a moderate level of community similarity. The water quality of Estuary of CikamalRiver is included into the heavily polluted waters whereas the Estuary of Cirengganis River belongs to the medium contaminated waters.

Relationship among carnivorous macrophyte Utricularia foliosa L. and species composition and life forms of periphytic algae community

Abstract Aim Present study evaluated the life forms and taxonomic structure of the periphytic algae community on Utricularia foliosa L. (modified leaf and stem) and artificial substrate during the four seasons in a tropical shallow reservoir. Methods We evaluated the periphyton on natural and artificial substrate in order to evaluate the influence of substrate type on the taxonomic structure of algal community. Monospecific stands of U. foliosa were selected. Water and periphyton sampling were performed within U. foliosa stands in the autumn (April/2010), winter (July/2010), spring (November/2010) and summer (February/2011). Nylon thread was used as the artificial substrate. The community structure was evaluated through life forms, species richness, diversity and species composition. Results Species diversity was significantly different only among seasons. The life forms and species richness were different between substrate types and seasons. Entangled filamentous algae had higher biovolume in the periphyton on artificial substrate and unicellular flagellated algae had higher biovolume on natural substrate. Species composition changed among the seasons and species descriptors differed among substrates types. Species-level taxonomic classification responded clearly to the substrate type. Conclusions We concluded that the taxonomic structure and life forms of periphytic algae on artificial substrate poorly represented the natural periphyton on U. foliosa. The type of substrate strongly influenced the periphyton–Utricularia relationship.