Coupled controls of climate, lithology and land use on dissolved trace elements in a karst river system

Abstract. Flood risk is impacted by a range of physical and socio-economic processes. Hence, the quantification of flood risk ideally considers the complete flood risk chain, from atmospheric processes through catchment and river system processes to damage mechanisms in the affected areas. Although it is generally accepted that a multitude of changes along the risk chain can occur and impact flood risk, there is a lack of knowledge of how and to what extent changes in influencing factors propagate through the chain and finally affect flood risk. To fill this gap, we present a comprehensive sensitivity analysis which considers changes in all risk components, i.e. changes in climate, catchment, river system, land use, assets, and vulnerability. The application of this framework to the mesoscale Mulde catchment in Germany shows that flood risk can vary dramatically as a consequence of plausible change scenarios. It further reveals that components that have not received much attention, such as changes in dike systems or in vulnerability, may outweigh changes in often investigated components, such as climate. Although the specific results are conditional on the case study area and the selected assumptions, they emphasize the need for a broader consideration of potential drivers of change in a comprehensive way. Hence, our approach contributes to a better understanding of how the different risk components influence the overall flood risk.

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Evaluating and Predicting the Effects of Land Use Changes on Hydrology in Wami River Basin, Tanzania

Hydrology ◽

10.3390/hydrology7010017 ◽

2020 ◽

Vol 7 (1) ◽

pp. 17 ◽

Cited By ~ 2

Author(s):

Sekela Twisa ◽

Shija Kazumba ◽

Mathew Kurian ◽

Manfred F. Buchroithner

Keyword(s):

Land Use ◽

Water Resources ◽

Assessment Tool ◽

Swat Model ◽

Land Use Changes ◽

Management Strategies ◽

River System ◽

Least Squares Regression ◽

Natural Forests ◽

The Impact

Understanding the variation in the hydrological response of a basin associated with land use changes is essential for developing management strategies for water resources. The impact of hydrological changes caused by expected land use changes may be severe for the Wami river system, given its role as a crucial area for water, providing food and livelihoods. The objective of this study is to examine the influence of land use changes on various elements of the hydrological processes of the basin. Hybrid classification, which includes unsupervised and supervised classification techniques, is used to process the images (2000 and 2016), while CA–Markov chain analysis is used to forecast and simulate the 2032 land use state. In the current study, a combined approach—including a Soil and Water Assessment Tool (SWAT) model and Partial Least Squares Regression (PLSR)—is used to explore the influences of individual land use classes on fluctuations in the hydrological components. From the study, it is evident that land use has changed across the basin since 2000 (which is expected to continue in 2032), as well as that the hydrological effects caused by land use changes were observed. It has been found that the major land use changes that affected hydrology components in the basin were expansion of cultivation land, built-up area and grassland, and decline in natural forests and woodland during the study period. These findings provide baseline information for decision-makers and stakeholders concerning land and water resources for better planning and management decisions in the basin resources’ use.

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Occurrence and distribution of dissolved trace elements in the surface waters of the Yakima River basin, Washington

10.3133/wri024177 ◽

2003 ◽

Keyword(s):

Trace Elements ◽

River Basin ◽

Surface Waters ◽

Yakima River ◽

Dissolved Trace Elements

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Effects of land use and water quality on greenhouse gas emissions from an urban river system

10.5194/bg-2020-311 ◽

2020 ◽

Author(s):

Long Ho ◽

Ruben Jerves-Cobo ◽

Matti Barthel ◽

Johan Six ◽

Samuel Bode ◽

...

Keyword(s):

Water Quality ◽

Land Use ◽

Urban Areas ◽

Anthropogenic Activities ◽

Ghg Emissions ◽

Flow Characteristics ◽

River System ◽

Urban River ◽

Polluted Water ◽

Land Use Types

Abstract. Rivers act as a natural source of greenhouse gases (GHGs) that can be released from the metabolisms of aquatic organisms. Anthropogenic activities can largely alter the chemical composition and microbial communities of rivers, consequently affecting their GHG emissions. To investigate these impacts, we assessed the emissions of CO2, CH4, and N2O from Cuenca urban river system (Ecuador). High variation of the emissions was found among river tributaries that mainly depended on water quality and neighboring landscapes. By using Prati and Oregon Indexes, a clear pattern was observed between water quality and GHG emissions in which the more polluted the sites were, the higher were their emissions. When river water quality deteriorated from acceptable to very heavily polluted, their global warming potential (GWP) increased by ten times. Compared to the average estimated emissions from global streams, rivers with polluted water released almost double the estimated GWP while the proportion increased to ten times for very heavily polluted rivers. Conversely, the GWP of good-water-quality rivers was half of the estimated GWP. Furthermore, surrounding land-use types, i.e. urban, roads, and agriculture, significantly affected the river emissions. The GWP of the sites close to urban areas was four time higher than the GWP of the nature sites while this proportion for the sites close to roads or agricultural areas was triple and double, respectively. Lastly, by applying random forests, we identified dissolved oxygen, ammonium, and flow characteristics as the main important factors to the emissions. Conversely, low impact of organic matter and nitrate concentration suggested a higher role of nitrification than denitrification in producing N2O. These results highlighted the impacts of land-use types on the river emissions via water contamination by sewage discharges and surface runoff. Hence, to estimate of the emissions from global streams, both their quantity and water quality should be included.

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The occurrence and distribution of antibiotics in the Karst river system in Kaiyang, Southwest China

Water Science & Technology Water Supply ◽

10.2166/ws.2018.026 ◽

2018 ◽

Vol 18 (6) ◽

pp. 2044-2052 ◽

Cited By ~ 4

Author(s):

Shengzhang Zou ◽

Fuyang Huang ◽

Liang Chen ◽

Fei Liu

Keyword(s):

Southwest China ◽

River Flow ◽

Wastewater Treatment Plants ◽

River System ◽

Contamination Source ◽

Antibiotic Concentration ◽

Detection Frequency ◽

Karst River ◽

Flow Quantity ◽

Total Concentrations

Abstract To our knowledge, this was the first study to investigate the occurrence and distribution of antibiotics in the Karst river system in Kaiyang, Southwest China. Ten water samples were collected from the Karst river in Kaiyang, Southwest China. Thirty-five antibiotics, including nine sulfonamides, four tetracyclines, five macrolides, sixteen quinolones and chloramphenicol, were analyzed. The results suggest that antibiotics are widely prevalent in the Karst river, with macrolides and quinolones being the most dominant and occupying 47% and 43% of total antibiotic concentration, respectively. The maximum total concentrations of sulfonamides, tetracyclines, macrolides, and quinolones were 30.4, 421, 884, and 1,807 ng/L, respectively. Lincomycin, roxithromycin, nalidixic acid, ofloxacin, and norfloxacin were detected in all samples with a detection frequency of 100%. The main sources of antibiotics were wastewater treatment plants (WWTPs) and rural dumps that did not contain sanitary treatment, which accounted for 33% and 40% of the total antibiotics present in the Karst river. Due to an increase in river flow quantity, the presence of WWTPs and rural dumps did not affect the concentration and distribution of antibiotics in the Karst river; however, the mass flux of antibiotics were significantly affected by the contamination source and the poor natural attenuation.

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Drainage history and land use pattern of a Swedish river system — their importance for understanding nitrogen and phosphorus load

Nutrient Dynamics and Retention in Land/Water Ecotones of Lowland, Temperate Lakes and Rivers ◽

10.1007/978-94-011-1602-2_31 ◽

1993 ◽

pp. 285-296

Author(s):

Andreas Krug

Keyword(s):

Land Use ◽

River System ◽

Phosphorus Load ◽

Nitrogen And Phosphorus ◽

Land Use Pattern ◽

Nitrogen And Phosphorus Load ◽

Use Pattern

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Assessing the impacts of hydrologic and land use alterations on water temperature in the Farmington River basin in Connecticut

Hydrology and Earth System Sciences ◽

10.5194/hess-23-4491-2019 ◽

2019 ◽

Vol 23 (11) ◽

pp. 4491-4508 ◽

Cited By ~ 5

Author(s):

John R. Yearsley ◽

Ning Sun ◽

Marisa Baptiste ◽

Bart Nijssen

Keyword(s):

Land Use ◽

Water Temperature ◽

River Basin ◽

Land Surface ◽

Canopy Cover ◽

River System ◽

Stream Temperature ◽

Hydrologic Model ◽

Riparian Buffers ◽

Connecticut River

Abstract. Aquatic ecosystems can be significantly altered by the construction of dams and modification of riparian buffers, and the effects are often reflected in spatial and temporal changes to water temperature. To investigate the implications for water temperature of spatially and temporally varying riparian buffers and dam-induced hydrologic alterations, we have implemented a modeling system (DHSVM-RBM) within the framework of the state-space paradigm that couples a spatially distributed land surface hydrologic model, DHSVM, with the distributed stream temperature model, RBM. The basic modeling system has been applied previously to several similar-sized watersheds. However, we have made enhancements to DHSVM-RBM that simulate spatial heterogeneity and temporal variation (i.e., seasonal changes in canopy cover) in riparian vegetation, and we included additional features in DHSVM-RBM that provide the capability for simulating the impacts of reservoirs that may develop thermal stratification. We have tested the modeling system in the Farmington River basin in the Connecticut River system, which includes varying types of watershed development (e.g., deforestation and reservoirs) that can alter the streams' hydrologic regime and thermal energy budget. We evaluated streamflow and stream temperature simulations against all available observations distributed along the Farmington River basin. Results based on metrics recommended for model evaluation compare well to those obtained in similar studies. We demonstrate the way in which the model system can provide decision support for watershed planning by simulating a limited number of scenarios associated with hydrologic and land use alterations.

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