Small Watercourses Research Articles

Implementation of the EU Water Framework Directive in monitoring of small water bodies in Hungary, I. Establishment of surveillance monitoring system for physical and chemical characteristics for small mountain watercourses

The EU Water Framework Directives (WFD) prescribes to achieve a good status of surface waters by 2015. To keep this deadline of a new three level (surveillance, operational and investigative) monitoring system is required, including hydro-morphological, biological and chemical elements. The status of a water body should be related to the reference conditions, depending on surface water types. In Hungary, the standard monitoring network for surface water quality has been operated for rivers and large lakes; however no satisfactory information is available for small water bodies. Therefore, there is an urgent need to design a methodology to develop a monitoring network for small watercourses. For this purpose a slightly impacted mountain stream (Nagy Stream in Mátra Mountains), was selected and intensively monitored during three years (May 2002 → May 2005). Hydrological, biological and chemical parameters required by WFD were monitored in this program. Variability of parameters vs. time and space was also investigated. The minimum frequency of sampling was determined for chosen physico-chemical components to meet the WFD standards for confidence. It was found that the minimum frequency of sampling suggested by WFD in space and time may not be adequate for precise and accurate characterization of water quality.

Water quality of flatland small watercourses on the Hungarian Upper-Tisza Region

Water quality of flatland small watercourses on the Hungarian Upper-Tisza Region

Causes and effects of morphological changes of the regulated channel of the river Toplica

The regulation of small torrential watercourses outside the urbanized areas is often based on the so-called field type of regulation. In the selection of this concept, after the regulation works, the new channel is left to the natural process of the morphological formation of the water cross-section taking care not to disturb the general stability of the regulated channel. We present the process of morphological development of the regulated channel of the river Toplica, tributary of the river Kolubara, in the period 1982-2004 i.e. from immediately after the regulation works to the present day.

Water Quality changes in the Elbe River Basin

In the course of the 90s, the Czech part of the Elbe river basin underwent a significant change in the quality of surface water. After a long period of intensified pollution hitting the peak at the end of the 80s, reduced amount of emissions from main industrial and municipal sources led to a lower pollution load of the Elbe and its principal tributaries. The scope and speed of such water quality changes is unprecedented in the Czech as well as in the European perspective. Decrease in the pollution level is however spatially limited to the Elbe river and its main tributaries. Further reduction of emission load will not result in corresponding decline of water pollution. This is due to different evolution of rivers of different sizes, but mainly to insufficient decrease of pollution load in the he ad stream areas of the river basin. It is this area of small watercourses that has to be in the centre of attention because without its radical changes it isn't possible to ensure permanent improvement of water quality in the Elbe and its tributaries.

Effect of wastewater treatment plant discharges on the functional nitrifying communities in river sediments

Sediments were collected in three small water courses upstream and downstream a water treatment plant discharge, in one highly fertilized eutrophic pond, and from one oligotrophic brook. They were analysed for ammonium oxidation activity, for nitrite oxidation activity and for their respective nitrifying community size. The relationships between variables was investigated by a principal components analysis of the physicochemical and biological data. Upstream sites of treatment plant discharges looked similar to an oligotrophic river, but the downstream sites have certain similarities with a highly eutrophic pond. Globally, whatever the hydrosystem, the organic carbon and organic nitrogen content of the sediments were highly correlated with nitrifying activity and nitrifiers number (significance level α = 0.001), but there was no significant correlation between the nitrifiers number and the related activity. The hypothesis of a role of the grain size on the nitrification communities was tested. A Mann-Withney U test (α = 0.05) indicated that, whatever the sediment, the two fractions of sand (500–200 μm and 200–50 μm) were non significantly different for nitrification. Conversely, the silt-clay fraction was significantly different from sands for all the nitrification's parameters. This silt-clay fraction exhibited the highest functional nitrifying community per mass unit indicating that the silt fraction is a main contributor to the nitrification process in river sediment. Finally, for each river, there were significant differences (at α = 0.05) between the nitrifiying communities in downstream and upstream sediments. In the 3 studied rivers, upstream sites were significantly higher in terms of activity and in terms of number of nitrifying bacteria. The effect of wastewater effluents discharge seems to be site specific.

Did the diverson of a small water course change the course of the history?

The 600th anniversary of the Battle of Ankara between the Mongol and Ottoman armies—the subject of this article—was observed on 28 July.Throughout history, water has played an important role in military camgaigns and battles.

Anthropogenic changes in the freshwater fish fauna of Italy, with reference to the central region and Barbus graellsii, a newly established alien species of Iberian origin

In a survey of the west‐central Italian rivers Ombrone, Fiora, Albegna and Bruna, among established exotic species, the Iberian barbel Barbus graellsti was recorded in Italian fresh waters for the first time. Morphological identification was supported by comparison of cytochrome b sequences with those from related barbel species. Other exotics of particular note were Barbus barbus, Pseudorasbora parva and Leuciscus cephalus, together with the Padano‐Venetian Chondrostoma genei and Padogobius bonelli. Native species still present included Leuciscus lucumonis, Telestes muticellus, Rutilus rubilio and Padogobius nigricans, but were now more restricted to upper reaches and smaller watercourses. The deleterious effect of alien species on native forms is discussed with particular reference to probable competition between C. genei and L. lucumonis, and between the two gobies. The checklist of species introduced to the fresh waters of Italy is now updated to 34. For the Italian freshwater fish fauna in general, the conservation status of three native species (Acipenser naccari, Salmo marmoratus and Knipowitschia punctatissima) has been improved but five species are believed to be at risk (Salmo carpio, L. lucumonis, Scardinius scardafa, Gobio benacensis and P. nigricans) and four anadromous species (Petromyzon marinus, Lampetra fluviatilis, Acipenser sturio and Huso huso) no longer breed in Italian fresh waters. The processes of change in the composition of the Italian freshwater fish fauna as a whole may be summarized as successively ‘padanization’, ‘danubization’ and now ‘globalization’.

Impact assessment of drought mitigation measures in two adjacent Dutch basins using simulation modelling

The impact of two mitigation measures on groundwater and streamflow droughts in two lowland basins was investigated by applying the comprehensive transient model SIMGRO. Catchment behaviour was simulated with meteorological data from 27 yrs. Raising the water levels in the primary watercourses and raising the beds of the small watercourses was found to mitigate groundwater droughts. Surprisingly, the river discharges during low flow periods were also reduced, indicating that streamflow drought lasts longer and total discharge deficit increases. The simulation modelling also shows that urban expansion in two adjacent basins where all the storm water on the paved surfaces is directed to a sewage treatment plant in one of the basins mitigates the streamflow droughts there. However, if the storm water on the paved surfaces infiltrates into the ground within the city limits, the total drought duration and total discharge deficit increase. In the adjacent basin with no treatment plant, urban expansion combined with storm water infiltration mitigates the droughts.

Toxicity and Accumulation of Al in the Acid Water of Small Lakes and Watercourses in Finnish Lapland

On the basis of a study of the hydrochemical regime and the status of benthic acidophobic species in the acidified watercourses and small lakes of Finnish Lapland, humic compounds are demonstrated to be the principal factors controlling both pH and the proportions of different forms of Al in water. It is found that the concentration of labile aluminum, i.e., that form of aluminum which is most toxic for aquatic organisms, increases only in acid water (pH 4.8–6.5) with a low and extremely low humic content of water (with a color of 5–60 mg Pt/l). Humic and other organic substances that fix Al in an inert or another stable form are demonstrated to be able to decrease the toxic properties of aluminum for acidophobic species and the capacity of aluminum to be accumulated in the bodies of aquatic organisms. Aluminum is shown to have no tendency to an increased rate of accumulation in the bodies of aquatic organisms that form the highest trophic level of secondary predators.

Heavy metals in rivers of Latvia

Total heavy metal concentrations in waters and sediments (HNO 3 digestible Pb, Cu, Co, Ni, Mn, Zn) and their speciation forms in sediments (exchangeable, carbonate bound, iron–manganese oxide bound, organic matter bound and residual) in major and common small watercourses (31 sampling stations) along their flow in Latvia were determined. The metal loads entering the Baltic Sea from Latvia were calculated. Increased metal concentrations were found only in lower reaches of the largest rivers and locally around known industrial pollution sources. Differences in metal concentrations and loads in rivers from different regions of Latvia were related to natural geochemical processes. Metal speciation analysis showed that the dominant metal species are residual metals and those bound to organic matter. Residual and carbonate-bound metal dominated only in rhitral regions of rivers. The concentrations of exchangeable metals increased below pollution sources.

千川上水における水路の改修とその効果

The Senkawa-josui irrigation canal is a small artificial watercourse of treated wastewater from a sewage plant. The simple structure of the channel (linear flowing, concrete banks and uniform riverbed) and the presence of a large number of carp seemed to prohibit distribution of diverse species. In order to improve the situation, the concrete bank (80 m long) was removed and two semi-stagnant sections which large carp could not enter were made in April 1996. Aquatic plants were also planted in the area. The aquatic fauna and flora were researched for three years after the channel improvement.Many species were found soon after the improvement. Juvenile fish and tadpoles grew in the stagnant sections. Male dragonflies also created their territories in the stagnant sections and the females laid eggs in them. The number of species of benthic macroinvertebrates increased. Spotbill ducks and little egrets were also found in the improved area. Diverse relations between aquatic plants and insects were observed. Species diversity of aquatic organisms was successfully raised in the imprgved area, showing that changing simple channel structures to complicated ones can help increase the number of species in artificial watercourses and urban streams.

Microbial organic-nitrogen transformations along the Swale–Ouse river system, Northern England

Organic-nitrogen transformations (extracellular aminopeptidase activity and bacterial assimilation of amino acids) were measured in river water, at 1 or 2-monthly intervals from May 1995 to May 1996, at six sites along 148 km of the Swale–Ouse and at sites on two tributaries, the River Wiske and Cod Beck. The aminopeptidase activity and amino-acid assimilation increased with distance downstream, as did bacterioplankton and phytoplankton chlorophyll a. These were usually straight-line increases rather than being stepwise in immediate response to sewage-works discharges. Rates of downstream increase, per unit length of river, were greatest in summer. Aminopeptidase activity and amino-acid assimilation varied seasonally, with highest values in summer. Correlation coefficients and forced-entry multiple-regression analysis suggested that organic-nitrogen transformations were potentially controlled by both microbial abundance and environmental variables, especially temperature and flow. The inorganic nitrogen regime apparently had little effect. The ratios, V max for aminopeptidase activity/V max for amino-acid uptake, and turnover rate for aminopeptidase activity/turnover rate for amino-acid assimilation, were used as indicators of the balance between supply and demand of organic nitrogen to bacterioplankton. Low values of these ratios, potentially indicating limited supply of amino-acid nitrogen, were recorded at the more downstream sites in the summer months. Since, however, ammonium-N was abundant at the downstream sites, there might have been a switch, with change in distance downstream and season, in the relative importance of amino acids and ammonium as nitrogen source. The specific growth rate (SGR) of planktonic bacteria from upstream sites increased with addition of leucine or glucose, thus organic nitrogen or carbon may have been limiting. For a downstream site, however, only leucine promoted increased SGR, hence organic-N might have been limiting. Addition of NH 4-N did not increase SGR hence inorganic nitrogen appeared not to be of equal value to bacterioplankton. Rates of organic-nitrogen transformations in the River Wiske and Cod Beck resembled those in the middle and lower main river, as did bacterioplankton and phytoplankton abundance, inorganic-nitrogen concentrations and the composition of the aquatic macrophyte community. Thus, these tributaries, although they were small watercourses, were very different from the headstream of the main river, essentially being enriched lowland streams.

WIDENING THE WATERCOURSE WIDTH IN THE URBAN AREA

Widening the width is necessary to improve the water environment of the small watercourses in the urban area, besides the augmentation of the water flow or the improvement of the water quality.At least 7m width of watercourse is found to be necessary, if most people regard this watercourse has enough width. Many streams in Japanese urban area have only less than 3-5m width, and footpath and greens along the watercourses are also needed to see it. Then widening the watercourse width in the urban area often becomes an urgent task.

Variation in composition of stream bed sediments in a small watercourse

We investigated the regional and temporal variation of the composition stream of bed sediments of the Langbroekerwetering, The Netherlands, in particular the effect of effluent discharges of sewage treatment plants on the sediment composition. Before we could map the chemistry of the bed sediments we had to examine two aspects which might obscure regional variation, namely variation due to differences in clay and organic matter content and short range variation. To remove the effect of clay and organic matter, the concentrations in the bed sediment were normalized to a standard sediment with 7% clay and 5% organic matter. By means of a nested sampling we ascertained that the sediments were highly variable within short distances. By increasing the effective support size by collecting composite samples, the regional differences can be mapped. The number of subsamples needed for a composite sample was established at 25. From the mapping of the study area it appears that the two existing effluent discharges affect the sediment composition locally. In particular, concentrations of N, P, K, Na, Zn, and Cu are raised due to the discharge of effluent. Inlet of water from the River Rhine and the occurence of flood waves are the main sources of temporal variation in the bed sediment composition in the Langbroekerwetering.

Grasshoppers (Orthoptera, Saltatoria) on alpine and dealpine riverbanks and their use as indicators for natural floodplain dynamics

AbstractGravel banks with sparse vegetation are typical habitats of braided alpine and dealpine floodplains. They are not only habitats for semiaquatic or hygrophilous organisms, but include also xerophilous elements: 17 species of grasshoppers were recorded in the floodplain of the Upper Isar (Bavaria, FRG). In the alpine region, two species (Bryodema tuberculata, Chorthippus pullus) occur only in floodplains, colonizing young gravel banks with sparse vegetation. Population dynamics and habitat selection of Bryodema tuberculata, studied on the Upper Isar for several years, are characterized by small scale movements of marked individuals between neighbouring gravel banks and fluctuations of the abundance on different sections of the gravel banks. Furthermore, the periodic desiccation of small watercourses is important for the dispersal of the females by walking. Historically widespread, today its distribution corresponds to the few remaining inundation areas. The main causes of decrease and extinction in most localities are man‐made changes in floodplain dynamics. The building of retention reservoirs and the diverting of streams for hydropower influenced succession in the downstream floodplains. Most of the gravel banks with sparse vegetation changed into willow thickets or pine forests. All remaining inundation areas should be protected. Bryodema tuberculata is a good indicator for the balance between progressing succession and the reorganization of gravel banks by floods.

Hydraulic resistance of sand ripples

1. The results obtained (Figs. 1, 2, and 3) make it possible, without relating the calculation to the dimensions of the sand ripples, to determine λ, H, and v by the method of selection using Chezy's relationship, if i, the flow rate Qa and the water temperature, the fineness of the sand, and the cross section of the water course are known (i is equated to the slope of the free surface). In this case, the average value of the exponent N in relationship (22) (N=1.05 for small water courses and hydraulic flumes, H≤1.0 m, and N=1.08 for large water courses, \s>1.0 m) can be assigned as its value. The calculation should be performed within the above-indicated limits of variation in λ and the relative start-off velocities in accordance with the following sequence: a) based on the fineness of the sand, n* can be established from the curve presented in Fig. 3; b) a number of values of the average depth H can be assigned, and the corresponding values ofω determined — the area of the active section, v*, R, Re*d, and λ from (22),\(C = \sqrt {2g/\lambda } \), and the flow rate\(Q = \omega C\sqrt {Ri} \); and, c) the Q=f(H) curve from which the computed depth values Hc corresponding to the assinged flow rate Qa, and then the velocity of the flow vc can be constructed. The error associated with the accuracy of the λ determination is within 5%. 2. The v and H in hydraulic flumes and small water courses (H≤1.0 m, d50≤0.38−0.37 mm) are also calculated by selection using the Chezy relationship and (24) for the region Re=103−3.2·104 and from $$\lambda = 10^{0,5511g^2 \operatorname{Re} - 5,131g Re + 11} $$ for the region Re=3.2·104−106. The error is within the range of 20%.

Development of a Two-Stage Treatment Plant for Extensive Nitrogen and Phosphorus Elimination

The report describes low-cost development and design of a two-stage wastewater treatment plant for 90,000 PE to achieve the highest possible degree of phosphorus and nitrogen elimination. The receiving water body of the treatment plant is a small watercourse fed almost exclusively by treated wastewater. A significant improvement in the water quality of this watercourse is planned. In particular, the performance of the wastewater treatment plant will need to be enhanced. The plant operator, the Erft River Board, organized a competition to attract solutions for an appropriate development of the plant from several consultants. Apart from embodying the concept of extensive wastewater treatment, designs were expected to preserve the existing infrastructure of the two-stage treatment plant as far as possible. Following selection of the most suitable design, the intended process technology is currently being tested in a pilot-scale plant. Planning envisages advanced wastewater treatment processes, including enhanced biological phosphorus removal, chemical precipitation/flocculation, nitrification and denitrification and combined coagulation/filtration. The pilot-scale investigations are carried out in close co-operation between the water authorities, the plant operators, the consultant, and a university institute of sanitary engineering. The paper presents the design and first results of the pilot-scale investigations in terms of the parameters BOD5, COD, phosphorus, ammonia and nitrate.

Leuctra apenninicolaa new species of stonefly (Plecoptera: Leuctridae) from the apennines (Italy)

Leuctra apenninicola sp. n. is described and compared with the closely related L. insubrica Aubert, including figures of the abdomens of both species. L. apenninicola occurs in small watercourses, mainly between 600 and 1500 m, and emerges from spring to summer. It occurs in the Apennines from Lombardia to Toscana.

TRANSPORT OF ROAD‐SURFACE SEDIMENT THROUGH EPHEMERAL STREAM CHANNELS1

ABSTRACT: Since the majority of road drainage points in western Washington and Oregon enter small, often ephemeral streams rather than large, fish‐bearing waters, impact of road‐surface sediment on biota in permanent streams depends, to a large extent, on transport through these small watercourses. A series of experimental additions of road‐surface sediment was made to two ephemeral streams to examine the downstream transport of this material as a function of discharge and channel characteristics. These small streams were found to store large amounts of sediment washed from road surface. In no instance did either stream transport more than 45 percent of the added material to their mouths, distances of 95 and 125 m. Larger‐sized sediment particles were delivered at a lower rate than finer material. Added sediment <0.063 mm in size was transported efficiently through the systems at all but the lowest flows tested. Material between 0.5 and 0.063 mm and from 2.0 to 0.5 mm in size were retained at progressively higher rates, with sediment in the coarser size category never exceeding a delivery of 10 percent of the added material. There were significant differences in the transport of sediment in the two larger size categories between the two streams. These differences were due to a much greater amount of woody debris in the stream with the lower delivery rates, which acted to trap and hold sediment, as well as a slightly longer and less steep channel.

Decomposition of Ocotillo (Fouquieria splendens) Wood in the Colorado Desert of California

The weight loss of stem sections of ocotillo (Fouquieria splendens) was determined for 11 years in the Colorado Desert of California. Weight of a stem section was a function of original weight, time in the field and presence or absence of termites. A section weighing 10 g is estimated to have a half-life of 29 years without termites and 17 years if termites find the section. Small sections of stem decayed slightly more rapidly than larger sections. INTRODUCTION Decomposition in desert ecosystems is considered to be a slow process and, because of this, there can be more dead than live aboveground biomass (Hadley and Szarek, 1981). There are few measurements of natural rates of decomposition in deserts; however, examples of such studies include Haverty and Nutting (1975), who measured loss in wood due to termites over a period of one year; Comanor and Staffeldt (1978), who documented loss of weight by creosote bush (Larrea tridentata) parts over 5 months, and Fowler and Whitford (1980), who examined L. tridentata litter in bags over a period of 1-2 months. The purpose of this note is to report results of a study of weight loss in pieces of ocotillo (Fouquieria splendens) stem over 11 years. The study was prompted by a question about the stability of ocotillo populations: dead ocotillos are common in the western Colorado Desert of California, but small living individuals are very rare. Either dead ocotillos take a very long time to decay and, hence, the rarity of small living individuals reflects stationary recruitment or the population in the Colorado Desert of California is in a state of decline, with high rates of death and decomposition and a low rate of recruitment. This work was conducted at the southern end of the Anza-Borrego State Park, California (33 N lat, 116 W long). The area is a bajada between the Coyote Mountains to the N and the Jacumba Mountains to the W. The substrate is recent alluvium made up of locally derived andesitic volcanic rock mixed with granite and sedimentary rocks from the surrounding hills. The area is finely dissected with a microtopography of small water courses. The elevation is 275 m above sea level. In addition to Fouquieria splendens, Larrea tridentata, Ambrosia dumosa, Opuntia echinocarpa, 0. bagelovii and Encelia farinosa are abundant. METHODS Stems of living ocotillo were collected in January 1971 at the study site, cut into sections ca. 8.5 cm long (range 8.0-9.5 cm), dried at 85 C for 2 weeks, and then weighed to the nearest milligram. Average weight of the dried sections was 15.1 g 4 7.8 SD (range 5.0-30.9 g, n = 22). A wire was fastened around 15 sections together with a numbered metal tag. In the field, wires were fastened to wooden stakes and sections were left on the soil surface. Two sections were collected in 1972, 1973, 1974, 1977 and 1978. Five sections were collected in 1982. All sections were randomly selected. Sand was brushed from the sections, they were dried at 85 C and then weighed to determine loss. Analysis is based on a simple model in which the final weight is related to original weight by an allometric function: