River Catchment Area Research Articles

Shallow alluvial aquifers for drinking and agricultural purposes: a case study from Jia Bharali River Basin, North Brahmaputra Plain, India

A preliminary assessment of groundwater quality for drinking and irrigational purposes in the lower Jia Bharali river catchment and adjoining areas of North Brahmaputra Plain, India, was carried out with respect to major cations, anions, and trace elements. Water samples from 50 shallow alluvial dug wells were collected in wet and dry seasons for a period of 3 hydrological years (2008–2011). Seasonal analysis showed major cation and anion contents in a definite trend across the basin as Ca: 4.2–68.9 mg/L > Na 1.9–62.5 mg/L > Mg:1.0–29.2 mg/L > K (1.3–26.1 mg/L) and HCO3 (16–118 mg/L) > Cl (2.8–138.3 mg/L) > SO4 (1.2–99.5 mg/L) > PO4 (BDL—1.50 mg/L) > NO3 (BDL—1.20 mg/L) within WHO acceptable limit for drinking water in all the seasons. Low SAR ( 60% and Kelly’s Index > 1. However, majority of the wells were found not suitable for drinking as well as irrigational purposes due to the presence of trace elements Cd (BDL—0.070 mg/L), Cr (BDL—0.24 mg/L), Fe (0.10–11.76 mg/L), Mn (BDL—1.37 mg/L), Ni (BDL—0.18 mg/L), and Pb (BDL—0.22 mg/L) beyond their respective standard limits. Piper trilinear diagram identified the major hydrochemical facies of the groundwater as alkaline earths (Ca, Mg) and weak acids (HCO3) over alkalis (Na, K) and strong acids (SO4, Cl).

Regeneration Patterns of Tree Species Along an Elevational Gradient in the Garhwal Himalaya

This study assessed the regeneration status of tree species at different elevations in Himalayan forests. For this purpose, we assessed the densities of seedlings, saplings, and adult trees of various forest-forming species to understand their population structure and regeneration patterns. Five elevational ranges—<2000, 2000–2500, 2500–3000, 3000–3500, and >3500 m above sea level—were selected in various ranges in the Bhagirathi River catchment area in the Garhwal Himalaya. The highest species richness was recorded at the lowest elevational range, and the lowest species richness was recorded at the highest elevational range. Species diversity, measured using the Simpson and Shannon–Wiener diversity indices, was highest at the lowest elevations and lowest at the highest elevations. Abies spectabilis, Cedrus deodara, Rhododendron arboreum, Pinus roxburghii, and Quercus oblongata were dominant and widely adapted with appropriate regeneration potential at various elevations, whereas Aesculus indica, Juglans regia, and Sorbus cuspidata showed less ability to regenerate, indicating a threat to their survival in the near future. Tree species of subalpine forests Abies pindrow, A. spectabilis, Acer acuminatum, Betula utilis, and R. arboreum were observed to expand their upper limits into alpine meadows. Weak regeneration by some dominant tree species, and expansion by a few less-dominant or even rare species, indicate likely future compositional changes in Himalayan forests.

Environmental assesment of surface waters based on monitoring data and neuro-evolutive modelling

Abstract The surface water quality highly depends on the natural conditions and on the industrial, agricultural and other anthropogenic activities in the river catchment areas. The quality of the surface water is the key factor in the water quality management. The monitoring of the water quality indicators is requested to follow up (in time and space) the changes in the water quality, providing healthy water for the people. The water quality indicators (physical-chemical specific parameters such as: pH, electrical conductivity, dissolved oxygen, turbidity etc.) provide information about the pollution degree of different waters (stemming from wastewater treatment plants, precipitation, sewer lines, tributaries, etc.). The main aim of the research was to demonstrate the efficiency of artificial intelligence techniques for the water quality prediction. Consequently, the considered system was modelled using a neuro-evolutive technique, combining artificial neural networks (ANN) with differential evolution (DE) algorithm. The neural network acts as a system model, while the differential evolution algorithm is the optimizer with the function to determine the optimal parameters of the model. The simulation results pointed out that the approach is suitable to set up adequate models for the three parameters, pH, electrical conductivity, dissolved oxygen, respectively. For the fourth parameter (turbidity), an average absolute error of 30% was obtained, which indicates a more complex relation in rapport to the other parameters of the system. The DE-ANN approach can, thus, be further used in decision making solutions for water quality management.

Distribution and contamination status of phthalic acid esters in the sediments of a tropical monsoonal estuary, Cochin – India

Phthalic acid esters (PAEs) are a group of endocrine-disrupting chemicals listed as priority pollutants by United States Environmental Protection Agency (USEPA, 2009). This study provides baseline information on seasonal distribution and contamination status of six phthalic acid esters (∑6PAEs) in sediments of a tropical estuary (Cochin-India). In general, the sediments accumulated more PAEs during the post monsoon (mean 2325 ngg−1; between 1402 and 3121 ngg-1) and monsoon (mean 1372 ngg−1; between 331 and 4015 ngg−1) periods indicating land run off as the major transport pathway. Moderate run off and comparatively high residence time lead to effective sorption and settling of PAEs in the surface sediments during post monsoon season. Despite a high discharge of PAEs in to the water column, their deposition on to the sediments occurs at a lower rate during monsoon than that post monsoon season. PAEs were (mean 810 ngg−1; between 44 and 1722 ngg-1) lowest in pre monsoon season. The pre monsoon season is characterized by a minimal runoff consequent to the trapping of these organic pollutants in the river catchment area. The mid and high molecular PAEs (DEHP-Di ethylhexyl phthalate, BBP-Benzyl butyl phthalate and DnBP-Di-n-butyl phthalate) were the dominant congeners relative to the low molecular weight congeners (DMP-Dimethyl phthalate and DEP-Diethyl phthalate). DEHP and BBP levels exceeded permissible risk levels indicating a serious ecological hazard to the estuarine ecosystem.

Effect of Present-Day Climate Changes and Agricultural Activities on Spring Overland Runoff in Forest-Steppe and Steppe Regions of the Russian Plain

Space and time analysis of the formation of spring overland runoff in forest-steppe and steppe regions of the Russian Plain has been carried out. It has been shown that, in addition to zonal climate conditions, its distribution over the area is largely determined by the agricultural load on river catchment areas, primarily, the structure of agricultural lands—the proportions of areas under winter tillage and consolidated tillage. The character of overland runoff response to present-day climate changes and agricultural activity has been identified, and quantitative estimates have been given to the manifold hydrological role of these factors.

Evaluación del efecto sobre el metabolismo hídrico de la ciudad Bogotá como respuesta al cambio en el modelo de gestión del agua en los años 90

Durante la decada de los noventa, Colombia y, en particular, la ciudad de Bogotá ha experimentado cambios en sus modelos de la gestión del recurso hídrico. En este artículo se calculó la huella hídrica de Bogotá para evaluar la incidencia de los cambios de modelo de gestión sobre el consumo del líquido y los vertimientos de aguas en la capital de la república. Como resultado, se obtuvo que la ciudad, entre 1993 y 2008, logró disminuir sus consumos en un 40% a pesar de su progresivo crecimiento y de que el decrecimiento de la presión sobre el recurso hídrico es una respuesta a los cambios administrativos, legislativos y culturales adelantados en Bogotá durante el periodo de tiempo mencionado. No obstante, el tema de manejo de vertimientos resultó ser un eslabón crítico, ya que la huella hídrica gris representa el 55,8% de la huella total de la capital, en la cual los aportes de vertimientos en la cuenca del río Tunjuelo resaltan como el mayor contaminante.

The influence of the deep seated geological structures on the landscape morphology of the Dunajec River catchment area, Central Carpathians, Poland and Slovakia

Abstract The area of the Dunajec river basin includes several geological units in the Central Carpathian region at the Polish-Slovakian borderland. The paper focuses on the geomorphometric parameters of the drainage system to recognize the influence of the deep seated geological structures on the morphology of the Dunajec river basin (Central Carpathians). The study were enriched with analysis of the geological maps and lineaments extracted from Digital Elevation Model. According to the obtained results, the massive NW-SE trending fault zones play a vital role in the geological architecture of the researched area. The development of the secondary fault structures has been determined by these dislocations and the manifestation of their activity can be observed as deformations of some of the other tectonic structures along the main fault zones, especially at the folds’ axes. Additionally, the geometric and morphometric features of the drainage system have also been influenced by the activity of these deep structures. The tectonic activity represented by the level of morphological rejuvenation, visible in the light of the morphometric parameters of the streams and the drainage basins, varies greatly between the tectonic units. This diversity is caused by both the lithological and structural features of these geological units.

Investigating the metal contamination of sediment transported by the 2016 Seine River flood (Paris, France)

Fine sediment transport in rivers is exacerbated during flood events. These particles may convey various contaminants (i.e. metals, pathogens, industrial chemicals, etc.), and significantly impact water quality. The exceptional June 2016 flood of the Seine River (catchment area: 65 000 km2, France), potentially mobilized and deposited contaminated materials throughout the Paris region. Flood sediment deposits (n = 29) were collected along the Seine River and its main tributaries upstream (Yonne, Loing and Marne Rivers) and downstream of Paris (Oise and Eure Rivers). Fallout radionuclides (137Cs, 7Be) were measured to characterize the sources of the material transiting the river, while trace elements (e.g. Cr, Ni, Zn, Cu, As, Cd, Sb, Pb, Tl, Ag) and stable lead isotopes (206Pb/207Pb) were analyzed to quantify the contamination of sediment transported during the flood. In upper sections of the Seine River, sediment mainly originated from the remobilization of particles with a well-balanced contribution of surface and subsurface sources. In the upstream tributaries, sediment almost exclusively originated from the remobilization of subsurface particles. In Paris and downstream of Paris, recently eroded particles and surface sources dominated, suggesting particles were mainly supplied by urban runoff and the erosion of agricultural soils. The highest metal concentrations and Enrichment Factors (EF) were found in the sediment collected in the Loing, Orge and Yvette upstream tributaries. Although these inputs were diluted in the Seine River, an increase in elemental concentrations was observed, progressing downstream through Paris. However, EFs in sediment collected along the Seine River were lower or in the same range of values sampled over the last several decades, reflecting the progressive decontamination of the urbanized Seine River basin.

HEC-RAS Hydraulic Model for Floodplain Area in Sembrong River

The study of floodplain is significant to human life and social economy. It can be seen that by using most computer models, locations of structures affected by floodwaters, such as bridges and roads cannot be effectively compared to the floodplain location in stream floodplain analysis. The purpose of this study is to develop an output of Hydrologic Engineering Center’s River Analysis System (HEC-RAS) hydraulic model and to enable one dimensional steady flow analysis. This study is applied to Sembrong river catchment area, located in Batu Pahat. Floodplain data features such as length of streams, bank position, streamline and cross-sections were used to produce river flow and its cross-sectional shape for each station along the study area. Total of 7 flow rate values were used to indicate an increase in the water level in order to accommodate the additional amount of water that flow into river. The results show that water will overflow into the floodplain at maximum flow rate of 24 m3/s. The hydraulic model had indicated that 33 out of 65 stations were unable to accommodate the maximum flow rate and thus will led to flooding. By developing the hydraulic model, it clearly shows that the results are more reliable and the affected area can be easily identified. The developed flood model can be a very useful tool in flood management of Sembrong river in terms of river development planning, flood mitigation measures, flood evacuation planning and addressing public awareness. This study proved that HEC-RAS is one of effective instrument for analysis and modeling

Segmenting tourism in rural area by emphasizing on motivational factors: Case study of Kolan river catchment area

Segmenting tourism in rural area by emphasizing on motivational factors: Case study of Kolan river catchment area

Analysis of potential future droughts limiting maize production, in the Luvuvhu River catchment area, South Africa

Recurring droughts associated with global warming have raised major concern for the agricultural sector, particularly vulnerable small-scale farmers who rely on rain-fed farming such as in the Luvuvhu River catchment. The Standardized Precipitation Evapotranspiration Index (SPEI) and Water Requirement Satisfaction Index (WRSI) were calculated to assess drought on a 120-day maturing maize crop based on outputs of the CSIRO-Mk3.6.0 under RCP 4.5 emission scenario, for the period 1980/81–2089/90. Results by SPEI show that 40–54% of the agricultural seasons during the base period experienced mild drought conditions (SPEI 0 to −0.99), equivalent to a recurrence of once in two seasons. However, WRSI results clearly indicated that stations in the drier regions (annual rainfall <600 mm) of the catchment experienced mild drought (WRSI 70 - 79) corresponding to satisfactory crop performance every season. Results further showed overall mild to moderate droughts in the beginning of the near-future climate period (2020/21–2036/37) with SPEI values not decreasing below −1.5. These conditions are then expected to change during the far-future climate period (2055/56–2089/90), whereby results on the expected crop performance predicted significantly drier conditions (p < 0.05). This study provided information on how farmers in the area can prepare for future agricultural seasons, while there is sufficient time to implement strategies to reduce drought risk potential. Thus, integrated interventions could provide best options for improving livelihoods and building the capability of farmers to manage climate change-related stresses.

Assessment of Potentially Toxic Elements as Non-Point Sources of Contamination in the Upper Crocodile Catchment Area, North-West Province, South Africa.

The concentration of potential toxic elements (PTEs) in the Upper Crocodile river catchment area in North-west Province, South Africa, was investigated. Water and sediment samples were collected among different land uses in the upper Crocodile River catchment area and analysed using inductively-coupled plasma–mass spectrometry (ICP–MS). Several guidelines were used to gauge the level of contamination and possible toxic effect of PTEs. The physicochemical analysis showed that electrical conductivity (EC), pH, and total dissolved solids (TDS) values complied with the recommended values of Department of Water and Forestry (DWAF) guidelines for South Africa. The average concentration of Cu, Pb, Cd, Zn, As, Cr, Al, and Mn in the water samples were lower than the recommended levels for water-quality guidelines for aquatic environments except for Fe, which exceeded the recommended values of DWAF of 0.1 mg/L and EPA (US) of 0.3 mg/L. The level of contamination was measured using the enrichment factor, contamination factor, and geoaccumulation index. The level of Cr was above the stipulated threshold limit of the sediment quality guideline for adverse biological effects, suggesting an ecotoxicology risk of anthropogenic origin, which was confirmed by statistical analysis. The non-point sources of PTEs are spatially distributed according to land-use types and are strongly correlated to land use.

An Evaluation of Aquifer Characteristics of the Idemili River Catchment Area of Southeast, Nigeria

An Evaluation of Aquifer Characteristics of the Idemili River Catchment Area of Southeast, Nigeria

Riverine flood assessment in Jhang district in connection with ENSO and summer monsoon rainfall over Upper Indus Basin for 2010

Pakistan has experienced severe floods over the past decades due to climate variability. Among all the floods, the flood of 2010 was the worst in history. This study focuses on the assessment of (1) riverine flooding in the district Jhang (where Jhelum and Chenab rivers join, and the district was severely flood affected) and (2) south Asiatic summer monsoon rainfall patterns and anomalies considering the case of 2010 flood in Pakistan. The land use/cover change has been analyzed by using Landsat TM 30 m resolution satellite imageries for supervised classification, and three instances have been compared, i.e., pre-flooding, flooding, and post-flooding. The water flow accumulation, drainage density and pattern, and river catchment areas have been calculated by using Shutter Radar Topography Mission digital elevation model 90 m resolution. The standard deviation of south Asiatic summer monsoon rainfall patterns, anomalies and normal (1979–2008) has been calculated for July, August, and September by using rainfall data set of Era interim (0.75° × 0.75° resolution). El Nino Southern Oscillation has also been considered for its role in prevailing rainfall anomalies during the year 2010 over Upper Indus Basin region. Results show the considerable changing of land cover during the three instances in the Jhang district and water content in the rivers. Abnormal rainfall patterns over Upper Indus Basin region prevailed during summer monsoon months in the year 2010 and 2011. The El Nino (2009–2010) and its rapid phase transition to La Nina (2011–2012) may be the cause of severity and disturbances in rainfall patterns during the year 2010. The Geographical Information System techniques and model based simulated climate data sets have been used in this study which can be helpful in developing a monitoring tool for flood management.

EFFECT OF HETEROGENEITY OF RIVERBED ON GROUNDWATER DISCHARGE IN SMALL RIVER BASIN UNDER NATURAL AND STRESSED CONDITIONS

A regional model of catchment of small river (catchment area is about1000 km2) is discussed. Model was developed to evaluate possible influence of hypothetical groundwater intake on river flow. The model was calibrated to measured groundwater heads and river flows. Geophysical and hydrometric survey allowed to characterize a heterogeneity of riverbed along the channel. River flow reduction, calculated on model with riverbed heterogeneity is greater by 25% compared to that calculated without heterogeneity. Thus it is shown that accounting for riverbed heterogeneity is advisable for more reliable prediction of impact of water intakes on environment.

Determination of oestrogen hormones in raw and treated water samples by reverse phase ultra-fast liquid chromatography mass spectrometry – a case study in Johannesburg South, South Africa

Hormones in water samples have been classified as ‘emerging pollutants’ and may pose a potential risk for humans. Hormones can be found in both surface and ground water at low concentrations. These compounds enter water streams through wastewater treatment plants (WWTP) and may elicit endocrine disruption to organisms. As a result of the low concentrations, a suitable analytical methodology is essential for their determination. In the past, residues of oestrogens in aqueous and solid environmental samples have commonly been analysed by gas chromatography (GC) equipped with mass spectrometry (MS). However, the necessary derivatisation steps are not only time consuming and laborious but also tedious. The first part of this case study was to develop a method to determine trace concentrations of the estrone (E1), 17α-estradiol (E2α), 17-β-estradiol (E2β) and 17-α-ethinylestradiol (EE2) hormones using reverse phase ultra-fast liquid chromatography mass spectrometry (RP-UFLC). Using the developed method, the second part of the case study was to determine the concentrations of the hormones in raw and treated potable water samples from the Vaal River catchment area in the south of Johannesburg, South Africa. Analytes were extracted by solid phase extraction (SPE C18 sorbent) cartridges and subsequently injected into ultra-fast liquid chromatography with the reverse phase column coupled to mass spectrometry (UFLC-MS) for analyte determinations. The limits of quantification were in the range of 0.24 to 0.32 ng·L-1 for the analytes. Accuracy was 95.6, 93.8, 97.6 and 100.9% for EE2, E2α, E2β and E1, respectively. In raw water samples taken during the rainy wet season, estrone was detected at concentrations of 0.90 and 4.43 ng·L-1. However, treated potable water samples did not contain detectable levels of hormones. This is potentially due to the ability of a water treatment process to remove endocrine disruptors during water purification.

Patterns of spatial distribution and migration phenology of common pochardsAythya ferinain the Western Palearctic: a ring‐recoveries analysis

We used ringed‐recoveries to assess: 1) the connectivity (movements of individuals) between the three putative flyways (north–west Europe, central Europe, south–west Asia) of common pochards in the Western Palearctic, 2) possible spatio‐temporal variations in the distribution of the species, and, 3) temporal evolution in spring and autumn migration dates. Based on winter counts of common pochards in the north–west European flyway, we distinguished three periods in the analyses (1960–1990, 1991–2000 and 2001–2016), which correspond to successive periods of population increase, peak and decline, respectively. Whatever the season (wintering or breeding) and period of ringing, large probabilities of ring‐recoveries outside the flyway of origin (ringing) were recorded, suggesting a high connectivity between the three putative flyways. There was a significant trend towards an earlier departure from the wintering area, and an eastward shift of spring recoveries over periods. In contrast, neither autumn/winter recovery locations, nor departure dates from the breeding area in Latvia and Russia changed over periods. The latter results do not support the hypothesis that short‐stopping (i.e. a reduction of fall migration distances/delaying of departure dates from the breeding area) could explain the observed decline of wintering common pochards in the north–west European flyway. Indirect recoveries support that large proportions of individuals wintering in western Europe may originate from the south–west Asia flyway and more particularly from a region in Siberia located in the Ob river catchment area. Considering trends in numbers for the three flyways together confirmed the “vulnerable” IUCN status of common pochard in the Western Palearctic as a whole, with a 35% decline over the last decade. The important connectivity between the northwest, central European and southwest Asian flyways call for considering such conservation problems at a much broader scale than the regional flyway.

Mycobacterium ulcerans DNA in Bandicoot Excreta in Buruli Ulcer-Endemic Area, Northern Queensland, Australia.

To identify potential reservoirs/vectors of Mycobacterium ulcerans in northern Queensland, Australia, we analyzed environmental samples collected from the Daintree River catchment area, to which Buruli ulcer is endemic, and adjacent coastal lowlands by species-specific PCR. We detected M. ulcerans DNA in soil, mosquitoes, and excreta of bandicoots, which are small terrestrial marsupials.

Assessment of Anthropogenic Impact on River Basins in Southern Kuzbass Mining Areas

The total pollution caused by spreading and fallout of atmospheric aerosols in river catchment areas of a coal-mining region is estimated. The contribution of the emission produced by a coal mine to the total fallout in the territory is assessed. Different types of water pollution in the coal-mining region are analyzed, the principal pollutants are identified, and their contribution to river water quality is assessed.

Model predictions of long-lived storage of organic carbon in river deposits

Abstract. The mass of carbon stored as organic matter in terrestrial systems is sufficiently large to play an important role in the global biogeochemical cycling of CO2 and O2. Field measurements of radiocarbon-depleted particulate organic carbon (POC) in rivers suggest that terrestrial organic matter persists in surface environments over millennial (or greater) timescales, but the exact mechanisms behind these long storage times remain poorly understood. To address this knowledge gap, we developed a numerical model for the radiocarbon content of riverine POC that accounts for both the duration of sediment storage in river deposits and the effects of POC cycling. We specifically target rivers because sediment transport influences the maximum amount of time organic matter can persist in the terrestrial realm and river catchment areas are large relative to the spatial scale of variability in biogeochemical processes.Our results show that rivers preferentially erode young deposits, which, at steady state, requires that the oldest river deposits are stored for longer than expected for a well-mixed sedimentary reservoir. This geometric relationship can be described by an exponentially tempered power-law distribution of sediment storage durations, which allows for significant aging of biospheric POC. While OC cycling partially limits the effects of sediment storage, the consistency between our model predictions and a compilation of field data highlights the important role of storage in setting the radiocarbon content of riverine POC. The results of this study imply that the controls on the terrestrial OC cycle are not limited to the factors that affect rates of primary productivity and respiration but also include the dynamics of terrestrial sedimentary systems.