Running Water Bodies Research Articles

Nitrates in Turkish waters: sources, mechanisms, impacts, and mitigation.

Intensive technological developments, rapid population growth and urbanization, and excessive use of nitrogen fertilizers have caused water resources to be contaminated substantially by nitrates in Turkey. The accumulated information should be evaluated to draw a nationwide attention to the problem. The aim of this review article was to highlight the importance of nitrate (NO3) contamination and to discuss the measures to be taken to mitigate the contamination across the nation. Agriculture, especially chemical fertilizers used in irrigated agriculture, was the most important source of NO3 in groundwater. Also, the industrial and domestic discharges substantially contributed to NO3 in both groundwater and surface waters in many cases. The most severe and widespread groundwater (e.g., 344 mg NO3 L-1 in İzmir, 476 mg L-1 in Afyon, 477 mg L-1 in Antalya, and 948.0 mg L-1 in Konya) and surface water contaminations (e.g., 293.8 mg NO3 L-1 in İzmir, 63.3 mg L-1 in Eskişehir, 89.8 mg L-1 in Edirne, and 90.6 mg L-1 in Sakarya) occurred in the regions where intensive agriculture, industrial development, and rapid urbanization were clustered. Well-established irrigation and fertilizer management plans are critical for reducing fertilizer-related NO3 contaminations in the irrigated agriculture. Special attention should be given to the regions where industrially and domestically contaminated running water bodies are in contact with groundwater. Discharge of wastewaters to the streams, creeks, rivers, and lakes should be prevented. Well-designed studies are needed to evaluate potential health effects, including the risk of cancer, of NO3 in drinking water.

What you sample is what you get: ecomorphological variation in Trithemis (Odonata, Libellulidae) dragonfly wings reconsidered

BackgroundThe phylogenetic ecology of the Afro-Asian dragonfly genus Trithemis has been investigated previously by Damm et al. (in Mol Phylogenet Evol 54:870–882, 2010) and wing ecomorphology by Outomuro et al. (in J Evol Biol 26:1866–1874, 2013). However, the latter investigation employed a somewhat coarse sampling of forewing and hindwing outlines and reported results that were at odds in some ways with expectations given the mapping of landscape and water-body preference over the Trithemis cladogram produced by Damm et al. (in Mol Phylogenet Evol 54:870–882, 2010). To further explore the link between species-specific wing shape variation and habitat we studied a new sample of 27 Trithemis species employing a more robust statistical test for phylogenetic covariation, more comprehensive representations of Trithemis wing morphology and a wider range of morphometric data-analysis procedures.ResultsContrary to the Outomuro et al. (in J Evol Biol 26:1866–1874, 2013) report, our results indicate that no statistically significant pattern of phylogenetic covariation exists in our Trithemis forewing and hindwing data and that both male and female wing datasets exhibit substantial shape differences between species that inhabit open and forested landscapes and species that hunt over temporary/standing or running water bodies. Among the morphometric analyses performed, landmark data and geometric morphometric data-analysis methods yielded the worst performance in identifying ecomorphometric shape distinctions between Trithemis habitat guilds. Direct analysis of wing images using an embedded convolution (deep learning) neural network delivered the best performance. Bootstrap and jackknife tests of group separations and discriminant-function stability confirm that our results are not artifacts of overtrained discriminant systems or the “curse of dimensionality” despite the modest size of our sample.ConclusionOur results suggest that Trithemis wing morphology reflects the environment’s “push” to a much greater extent than phylogeny’s “pull”. In addition, they indicate that close attention should be paid to the manner in which morphologies are sampled for morphometric analysis and, if no prior information is available to guide sampling strategy, the sample that most comprehensively represents the morphologies of interest should be obtained. In many cases this will be digital images (2D) or scans (3D) of the entire morphology or morphological feature rather than sparse sets of landmark/semilandmark point locations.

COMPARISONS OF MORPHOMETRIC CHARACTERISTICS AND LENGTH-WEIGHT RELATIONSHIP OF EUROPEAN EEL (ANGUILLA ANGUILLA L., 1758) IN TURKISH INLAND WATERS

European eels are found in all European rivers draining to seas. Comparisons of some morphometric characteristics and length-weight relationship parameters of European eel “Anguilla anguilla” collected from inland waters of Turkey were performed in this work. The 108 fish samples used in the current work were taken from the museum of Faculty of Fisheries, Ege University; they were captured from different running water bodies. Morphometric features like total length, weight, head length, head height, maximum body height, eye diameter, inter-orbital distance, snout length, dorsal fin length, anal fin length, pectoral fin length, predorsal distance, and preanal distance of the fish were measured. In addition, head length/maximum body height, head length/snout length, head length/head height, head length/total length, eye diameter/head length, eye diameter/inter-orbital distance, eye diameter/snout length and predorsal distance/preanal distance ratios were calculated. The analysed specimens ranged in total length from 12.70 to 64.10 cm, and in weight between 3.21 and 416.14 g. The length-weight relationship parameters were estimated as a=0.011, b=3.154; while r2 was calculated as 0.956.

Determination of trophic weight and indicator values of diatoms in Turkish running waters for water quality assessment

This study, the first such attempt in Turkey, aimed to investigate the distribution of diatom species related to the variation of total phosphorus (TP) in eight basins to determine trophic weight and indicator values of diatom species and to develop the Trophic Index-Turkey (TIT) for assessing the ecological status of freshwaters. The distribution of the diatom species in 225 running water bodies from 8 basins of Turkey was determined in 2014 (summer and fall) and 2015 (spring and summer) in association with TP variation. Trophic values for 219 species were determined during this study and many of these are presented for the first time. Optima and tolerance TP values were calculated for each species in the different aquatic ecosystems using weighted average regression. Diatom species such as Clevamphora ovalis , Caloneis amphisbaena , Gyrosigma acuminatum , Navicula tripunctata , and Nitzschia umbonata showed high trophic weight values, while Achnanthidium minutissimum , Cymbella excisa , Didymosphenia geminata , Hannaea arcus , and Meridion circulare had low trophic weight values. These findings provide supplementary information about the biotic integrity of the water bodies and could be used to develop the TIT for the bioassessment of freshwater ecosystems, especially running water bodies.

Predicting current and future background ion concentrations in German surface water under climate change.

Salinization of surface waters is a global environmental issue that can pose a regional risk to freshwater organisms, potentially leading to high environmental and economic costs. Global environmental change including climate and land use change can increase the transport of ions into surface waters. We fit both multiple linear regression (LR) and random forest (RF) models on a large spatial dataset to predict Ca2+ (266 sites), Mg2+ (266 sites), and [Formula: see text] (357 sites) ion concentrations as well as electrical conductivity (EC-a proxy for total dissolved solids with 410 sites) in German running water bodies. Predictions in both types of models were driven by the major factors controlling salinity including geologic and soil properties, climate, vegetation and topography. The predictive power of the two types of models was very similar, with RF explaining 71-76% of the spatial variation in ion concentrations and LR explaining 70-75% of the variance. Mean squared errors for predictions were all smaller than 0.06. The factors most strongly associated with stream ion concentrations varied among models but rock chemistry and climate were the most dominant. The RF model was subsequently used to forecast the changes in EC that were likely to occur for the period of 2070 to 2100 in response to just climate change-i.e. no additional effects of other anthropogenic activities. The future forecasting shows approximately 10% and 15% increases in mean EC for representative concentration pathways 2.6 and 8.5 (RCP2.6 and RCP8.5) scenarios, respectively.This article is part of the theme issue 'Salt in freshwaters: causes, ecological consequences and future prospects'.

Comparison of trophic structure of the benthic macroinvertebratesin three Bulgarian riverine water bodies

The trophic structure of benthic macroinvertebrates in three different types of running water bodies subjected to varying degrees of anthropogenic pressure was analyzed. A seasonal survey was conducted at three Bulgarian rivers in 2011. An adapted version of the multihabitat sampling method was applied along with measuring physical and chemical variables. The ecological status was defined by means of biotic and trophic indexes. Distribution of the functional feeding groups shows that the most sensitive groups, shredders and scrapers, dominate the trophic structure of the mountain river types. In contrast, groups of deposit feeders and filterers prevail at the foothill and plain rivers. Multidimensional scaling plot and redundancy analysis demonstrated that anthropogenic impact and altitude are the main factors determining the distribution of the benthic macroinvertebrates by different functional groups. Seasonality has no leading role in the trophic structure formation of the benthic communities. Our results showed a difference between the trophic composition of the macrozoobenthos found in the mountain sections and those found in the foothill/plain stretches of the rivers. A comparison between the last two areas demonstrated that there was no clear distinction between the trophic composition of the functional feeding groups.

A new diatom index to assess ecological quality of running waters: a case study of water bodies in western Anatolia

Diatoms are an important part of aquatic biodiversity and the main component of phytobenthos. They play a key role in aquatic ecosystems and indicate water quality. The European Union Water Framework Directive requires that phytobenthos be used for the ecological quality assessment of water. This study evaluated the ecological status of various watercourses in the western Mediterranean basin of Turkey using a multivariate approach and presents a new trophic index Turkey (TIT) based on diatom assemblages. Twenty-five running water bodies were seasonally monitored for biological and physicochemical analyses from summer 2014 to summer 2015. A total of 102 species belonging to 22 genera were recorded. Cymbella excisa Kützing, Gomphonella parvula (Kützing) Rabenhorst, Ulnaria ulna (Nitzsch) Compère, and Cocconeis communis f. placentula (Ehrenberg) Chmielevski were the most commonly found species. A canonical correspondence analysis was used to examine the relationship between species and environmental factors. The most effective explanatory factors, including nitrate nitrogen, electrical conductivity, altitude, total nitrogen, orthophosphate, and calcium carbonate significantly influenced the ecological preferences of diatom species in the ecosystems. TIT values ranged between 1.53 in Kaya creek and 2.73 in Dalaman stream (A8). Ecological status of water bodies was assessed using an ecological quality ratio based on trophic index Turkey (EQR-TIT) for each of the stations. EQR-TIT ranged from 0.44 in Dalaman stream (A8) to 0.99 in Kocabük creek during the study period. TIT had a high correlation coefficient (R2=0.77) with log total phosphorus and may be an appropriate diatom metric to assess the ecological status of water bodies.

Alternative ways to use and evaluate Kohler's ordinal scale to assess aquatic macrophyte abundance

To assess numerical information on the aquatic vegetation of running water bodies, the ‘Kohler method’, a five-level descriptor scale estimating the relative abundance of species in river sections as survey units has been frequently used. Although this scale is ordinal without any information on differences between the states, data are often evaluated by arithmetic operations as if they were on the ratio scale. Metrizing ordinal information may facilitate correct data evaluation; however, the outcome highly depends on mathematical procedures applied to the data set.This paper demonstrates that if ordinal data are analyzed by ordination methods suited to this scale type, then results primarily reflect presence/absences. To the contrary, additional information was added to Kohler's scale when the applied analyses used values on ratio scales; therefore they provided inappropriate data evaluation.Four different conversion methods (the use of 1–5 values, the third power, the mean values of Braun-Blanquet cover classes and the replacement of ordinal states by ranks) were applied to reveal how the conversion procedures determine the intervals between the substituting metric values and the level of importance given to species frequency and abundance. When ordinal scale was substituted by numbers 1–5 and ranks, frequency of species was taken greatly into account. After cubic conversion the large values became considerably overemphasized, therefore species occurring in a few (or very few) survey units with high abundance values were considered more dominant than less abundant but frequently present ones. The mean values of Braun-Blanquet's cover classes gave large ordinal scores and the frequent species to have substantive representation.The results demonstrate that conscious choice of intervals between the scores is inevitable; otherwise one generates unknown or misleading differences in species abundance. Although every researcher assessing aquatic macrophytes by Kohler's method surely has an idea on the differences between the applied scores, the use of identical, widely accepted scale substitution is prerequisite for reliable comparison.

Key to the larval stages of common Odonata of Hindu Kush Himalaya, with short notes on habitats and ecology

The order Odonata is one of the most widely studied groups among insects from the oriental region. They colonize in both stagnant and running water bodies of wide water quality. Hitherto, the existing literature on the Odonata contained numerous publications with coloured figures of adults, helpful for identification. Identification key with figures on larval stages, using their coloration as distinguishing characters are largely missing. The current work attempts to provide an identification key to aquatic larvae of the most common families of Zygoptera, Anisoptera and Anisozygoptera with colour illustrations. The specimens were collected from Nepal and India (northern part). Each family is represented by several examples to demonstrate the range of morphological variability. This key helps determination of aquatic larvae Odonata up to family level without enormous efforts in field and laboratory.

Interim Report on Studies of the Blackfly Fauna (Diptera, Simuliidae) of the ‘Waldviertel’ (Austria) along the Czech border

The northern ‘Waldviertel’ (the southern part of the geographical region ‘Bohemian Forest’), situated along the border with the Czech Republic, differs from all other Austrian ecoregions with respect to its climate, the geological and limnological situation. Studies of the Diptera family (fam. Culicidae) communities conducted in previous years showed that a greater part of the species are common in the alpine region or are distributed in northern Europe. The 2007/2008 investigation of Simuliidae larvae and pupae in several running water bodies of the northern Waldviertel was undertaken in order to verify whether the findings of the Culicidae studies hold true for Simuliidae. The early spring fauna of Simuliidae is dominated by Simulium rostratum and S. morsitans, whereas during the rest of the season mainly larvae and pupae of S. ornatum, S. reptans, S. (B.) erythrocephalum, S. (N.) vernum and S. (N.) carthusiense- Gr. were found. In early spring the collectors of samples were severely bitten by Simuliida...

Evaluation of the potential of various aquatic eco-systems in harnessing bioelectricity through benthic fuel cell: Effect of electrode assembly and water characteristics

Six different types of ecological water bodies were evaluated to assess their potential to generate bioelectricity using benthic type fuel cell assemblies. Experiments were designed with various combinations of electrode assemblies, surface area of anode and anodic materials. Among the 32 experiments conducted, nine combinations evidenced stable electron-discharge/current. Nature, flow conditions and characteristics of water bodies showed significant influence on the power generation apart from electrode assemblies, surface area of anode and anodic material. Stagnant water bodies showed comparatively higher power output than the running water bodies. Placement of cathode on algal mat (as bio-cathode) documented several folds increment in power output. Electron-discharge started at 1000 Ω resistance in polluted water bodies (Nacaharam cheruvu, Hussain Sagar lake Musi river), whereas, in relatively less polluted water bodies (Uppal pond/stream, Godavari river) electron-discharge was observed at low resistances (500/750 Ω).

Molecular identification, description, and phylogenetic implications of the tadpoles of 11 species of Malagasy treefrogs, genus Boophis

Based on specimens identified by DNA barcoding, we describe the tadpoles of 11 species of treefrogs (Boophis) in the Malagasy family Mantellidae. All tadpoles belong to species of the stream‐breeding clade within Boophis. Based on these and other published descriptions of Boophis tadpoles which develop in running water bodies, we tentatively distinguish three ecomorphological guilds for these larvae. Guild A, in which we describe the larvae of B. boehmei, B. reticulatus, B. pyrrhus, B. tasymena, and B. viridis which have few lotic adaptations, their oral disc width being 31–43% of body width, with a single row of 48–81 marginal papillae, and the first upper keratodont row having 58–144 keratodonts. Guild B, in which we describe the tadpoles of B. albilabris, B. madagascariensis, B. luteus, and of an undescribed species here named B. sp. aff. elenae, is intermediate, with an enlarged oral disc, an increasing number of keratodont rows and a lower height of the caudal fin. In these tadpoles, oral disc width is 43–63% of body width, they have one or two rows of 69–164 marginal papillae, and the first upper keratodont row has 164–238 keratodonts. Guild C contains tadpoles with a very large oral disc, living on submerged rocks and stones in stream sections of strong current. In this guild we describe the tadpoles of B. marojezensis and B. sibilans. Their oral disc width is 63–89% of body width, there are multiple rows of many marginal papillae, and the first upper keratodont row has many small keratodonts which are difficult to count, but consistently amount to over 200. In B. marojezensis, the dorsal gap in the marginal papillae rows, apparent in all other species, is closed. These larval morphologies show a rather good fit with recently published molecular phylogenetic data: species groups that were confirmed to be monophyletic in most cases have similar larval morphologies, and, in contrast, where species of the same group have disparate larval morphologies the monophyly of the group is questionable (e.g. the B. majori group). Nevertheless, some cases of convergent evolution are apparent, such as the highly specialized Guild C morphology, which may have evolved separately in the B. albipunctatus group, B. mandraka group, and in some species of the B. majori group.

Does habitat use explain large scale species richness patterns of aquatic beetles in Europe?

Regularities in species richness are widely observed but controversy continues over its mechanistic explanation. Because richness patterns are usually a compound measure derived from taxonomically diverse species with different ecological requirements, these analyses may confound diverse causes of species numbers. Here we investigate species richness in the aquatic beetle fauna of Europe, separating major taxonomic groups and two major ecological types, species occurring in standing and running water bodies. We collated species distributions for 800+ species of water beetles in 15 regions across western Europe. Species number in any of these regions was related to three variables: total area size, geographic connectedness of the area, and latitude. Pooled species numbers were accurately predicted, but correlations were different for species associated with either running or standing water. The former were mostly correlated with latitude, while the latter were only correlated with the measure of connectedness or with area size. These differences were generally also observed in each of the four phylogenetically independent lineages of aquatic Coleoptera when analysed separately. We propose that effects of habitat, in this case possibly mediated by different long term persistence of running and standing water bodies, impose constraints at the population or local level which, if effective over larger temporal and spatial scales, determine global patterns of species richness.