Clohesyomyces symbioticus sp. nov., a fungal endophyte associated with roots of water smartweed (Persicaria amphibia)

The widespread aquatic plant Persicaria amphibia (water smartweed, Polygonaceae) occurs in both flooded aquatic habitats and moist terrestrial environments. Its physiological versatility and wide geographic range highlight its resilience to stress and make the species intriguing for the study of fungal endophytes. Endophytes occur within living plant tissues and are known from diverse aquatic, marine, and terrestrial plants, where they often mitigate plant responses to stress. As part of a study evaluating endophyte communities associated with aquatic plants in lentic waters of Arizona, USA, we isolated a distinctive clade of endophytes from healthy, living roots of seasonally inundated P. amphibia, which we describe here on the basis of morphology and evidence from four loci as new species Clohesyomyces symbioticus (Lindgomycetaceae, Pleosporales, Dothideomycetes, Ascomycota). Clohesyomyces has long been considered a monotypic genus comprising the saprobic species C. aquaticus, presently known from submerged wood in freshwater systems in Asia and Australia. Description of Clohesyomyces symbioticus highlights the occurrence of endophytism in this genus and expands its geographic scope to the western hemisphere.

Diversity of Brazilian Troglobitic Fishes: Models of Colonization and Differentiation in Subterranean Habitats

The Brazilian subterranean ichthyofauna is distinguished worldwide by high taxonomic and phylogenetic diversity, involving at least 30 exclusively subterranean (troglobitic) lineages. This may be explained by high native epigean diversty, allied to opportunities for colonization and genetic isolation in the subterranean biotope, thence originating troglobites. An updated list of Brazilian troglobitic lineages and a review of previous hypotheses on modes of colonization and differentiation in subterranean habitats are presented with fresh data and models. Colonization of and isolation in the subterranean biotope are independent processes, usually separate over time. Access to subterranean habitats varies from the (sub)horizontal through sinkholes and resurgences of base-level streams and vadose tributaries to the vertical by shallow and deep phreatic waters through the hyporheic zone. Phenotypic differentiation of subterranean populations originating troglobites may be achieved by various, non-mutually exclusive modes of genetic isolation, e.g., directly in base-level streams and upper tributaries through the extinction of epigean populations, due to drainage discontinuation in dry paleoclimatic phases (or by other causes), by topographic isolation due to a lowering of the regional base level and karst catchments or by parapatric differentiation. Differentiation may also be a consequence of transition from lotic to lentic waters in flooded caves, and from shallow to deep phreatic habitats.

Biodiversity Patterns of Macroinvertebrate Assemblages in Natural and Artificial Lentic Waters on an Oceanic Island

The Azorean islands have been historically affected by human activities, mainly due to the combined effects of habitat degradation and fragmentation, and the introduction of exotic species. We here aim to analyze the role of environmental characteristics and spatial descriptors in supporting regional biodiversity of macroinvertebrates by considering natural ponds and artificial tanks. After the monthly variation of macroinvertebrate assemblages was assessed in three temporary and two permanent ponds in the Azorean island of Terceira during a complete inundation-desiccation annual cycle, the assemblage differences of 12 ponds (three temporary and nine permanent ponds) and 8 closely-located artificial tanks were analyzed across a range of landscape disturbances. Macroinvertebrate assemblages were found to differ according to hydroperiod and sampled months. Although the former explained the highest variance, macroinvertebrate differentiation by hydroperiod was also dependent on the study month. Our results also revealed a consistent monthly pattern of species replacement. However, the contribution of nestedness to the macroinvertebrate β-diversity was notable when temporary ponds were close to desiccation, probably indicating a deterministic loss of species due to the impoverished water conditions of the ponds facing desiccation. When the macroinvertebrate assemblages were analyzed in relation to physico-chemical variations and spatial descriptors, the artificial tanks were not clearly segregated from the natural ponds, and only differentiated by pH differences. In contrast, those natural ponds exhibiting high concentrations of total phosphorous (likely signs of anthropization) also discriminated the ordination of ponds in a distance-based redundancy analysis, and showed impoverished assemblages in comparison with well-preserved ponds. The macroinvertebrate assemblages of the natural ponds showed a significant spatial pattern, but this spatial influence was not significant when tanks and ponds were considered together. Our results suggest that tanks may act as possible reservoirs of biodiversity during the desiccation period of temporary ponds, but are unable to establish successful populations. These fishless permanent tanks can complement the conservation of a biodiversity that is largely maintained by the pristine high-altitude natural ponds. The establishment of a guideline for conservation management that also considers the artificial tanks is necessary to benefit the local and regional Azorean macroinvertebrate diversity.

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.

EVALUASI KUALITAS AIR WADUK BERDASARKAN PARAMETER FISIKA

Reservoir is a large building made by humans by damming a river (Wetzel, 2001). Reservoirs are also an intermediate system between rivers (lotic waters) and lakes (lentic waters). The manufacture of reservoirs generally has objectives and functions, one of which is for raw water needs from drinking water treatment. MG Reservoir is the main source of raw water for PDAM Balikpapan City. MG Reservoir is a very important aquatic resource in terms of its ecological and economic functions. Therefore it must be maintained both in terms of quantity and quality. With the existence of various human activities around MG Reservoir, it will affect the condition of the reservoir. Keywords— evaluation, quality, physics, temperature, transparency, electrical conductivity

Imbabura and Chimborazo at the cradle of Biogeography in the South American Andes

The present contribution is a comprehensive review of the status of biodiversity of freshwater zooplankton of Uttarakhand Himalaya. Uttarakhand harbours a wide diversity in freshwater habitats in terms of rapids, riffles, runs, cascades of falls and pools of rivers and streams and the shallow and swift water of springs and lentic waters of lakes, ponds and reservoirs with varied physico-chemical environmental variables. Freshwater zooplankton of Uttarakhand are composed of the taxa of Protozoa, Rotifera, Copepoda, Cladocera and Ostrocoda. Ritifera contributes maximum (40.50%) with thirty two species followed by Protozoa (22.78%) with eighteen species and Cladocera (22.78%) with eighteen species to the total zooplankton taxa of Uttarakhand. Copepoda contributes 8.86% with seven species, while minimum contribution (5.08%) with only four species is made by Ostracoda to the total zooplankton taxa of Uttarakhand. Seasonal variation in the abundance of zooplankton in addition to diurnal vertical migration in diverse freshwater habitats of Uttarakhand Himalayahas also been reported.

Microplastics in Freshwater: What Is the News from the World?

Plastic has become a “hot topic” for aquatic ecosystems’ conservation together with other issues such as climate change and biodiversity loss. Indeed, plastics may detrimentally affect habitats and biota. Small plastics, called microplastics, are more easily taken up by freshwater organisms, causing negative effects on growth, reproduction, predatory performance, etc. Since available information on microplastics in freshwater are fragmentary, the aim of this review is twofold: (i) to show, analyse, and discuss data on the microplastics concentration in freshwater and (ii) to provide the main polymers contaminating freshwater for management planning. A bibliographic search collected 158 studies since 2012, providing the scientific community with one of the largest data sets on microplastics in freshwater. Contamination is reported in all continents except Antarctica, but a lack of information is still present. Lentic waters are generally more contaminated than lotic waters, and waters are less contaminated than sediments, suggested to be sinks. The main contaminating polymers are polypropylene and polyethylene for sediment and water, while polyethylene and polyethylene terephthalate are mainly found in biota. Future research is encouraged (1) to achieve a standardised protocol for monitoring, (2) to identify sources and transport routes (including primary or secondary origin), and (3) to investigate trophic transfer, especially from benthic invertebrates.

Carbon emission related to thermokarst processes in wetlands of NE European Tundra

<p>Emission of greenhouse gases (GHG) from inland waters is recognized as highly important and understudied part of terrestrial carbon (C) biogeochemical cycle. These emissions are still poorly quantified in permafrost regions containing a vast amount of surface C in frozen peatlands. This is especially true for NE European peatlands, located within sporadic to discontinuous permafrost zone which is highly vulnerable to thaw. For a first quantification of the C emission from lentic waters of the Bolshezemelskaya Tundra (BZT, 200,000 km²), we measured CO2 and CH4 concentrations and fluxes to the atmosphere in 98 depressions, thaw ponds and thermokarst lakes ranging from 0.5 to 5x10<sup>6</sup> m² in size. The CO2 fluxes decreased by an order of magnitude when lake size increased by > 3 orders of magnitude, while CH4 fluxes showed large variability that were not related to lake size By using a combination of Landsat-8 and GeoEye-1 images we found that lakes cover 4% of BZT, and calculated the overall C emission (CO<sub>2</sub>+CH<sub>4</sub>) from the lakes of the territory to 3.8 Tg C y<sup>-1</sup> (99% C-CO<sub>2</sub>, 1% C-CH<sub>4</sub>). Large lakes (> 10,000 m²) dominated GHG emissions whereas small thaw ponds (< 1000 m²) had a minor contribution to overall lake surface area (< 2%) and GHG emission (< 5 % of CO<sub>2</sub>; < 20% of CH<sub>4</sub>). The results suggest that, if permafrost thaw in NE Europe leads to the disappearance of large thermokarst lakes and formation of new small thaw ponds and depressions, this will decrease GHG emission from lentic waters of this region. However, due to temporal and spatial variations of C fluxes, the uncertainties on areal GHG emission are at least one order of magnitude in small thaw ponds and a factor of 3 to 5 in thermokarst lakes.</p><p>This work was supported by the State Task AAAA-A18-118012390200-5, RFBR grant No. 18-05-70087 “Arctic Resources”, 19-07-00282, 18-45-860002, 18-45-703001 and 18-47-700001, and the Swedish Research Council (grant no. 2016-05275).</p>