Summary of synoptic sampling and tracer-injection tests in the Alamosa River basin during high-flow conditions, June 1999: A sampling analysis report for modeling reactive transport of metals for the Summitville Mine, Colorado

The purpose of the study was to analyze the formation conditions of catastrophic floods in the Iya River basin over the observation period, as well as a long-term forecast of the impacts of future climate change on the characteristics of the high flow in the 21st century. The semi-distributed process-based Ecological Model for Applied Geophysics (ECOMAG) was applied to the Iya River basin. Successful model testing results were obtained for daily discharge, annual peak discharge, and discharges exceeding the critical water level threshold over the multiyear period of 1970–2019. Modeling of the high flow of the Iya River was carried out according to a Kling–Gupta efficiency (KGE) of 0.91, a percent bias (PBIAS) of −1%, and a ratio of the root mean square error to the standard deviation of measured data (RSR) of 0.41. The preflood coefficient of water-saturated soil and the runoff coefficient of flood-forming precipitation in the Iya River basin were calculated in 1980, 1984, 2006, and 2019. Possible changes in the characteristics of high flow over summers in the 21st century were calculated using the atmosphere–ocean general circulation model (AOGCM) and the Hadley Centre Global Environment Model version 2-Earth System (HadGEM2-ES) as the boundary conditions in the runoff generation model. Anomalies in values were estimated for the middle and end of the current century relative to the observed runoff over the period 1990–2019. According to various Representative Concentration Pathways (RCP-scenarios) of the future climate in the Iya River basin, there will be less change in the annual peak discharge or precipitation and more change in the hazardous flow and its duration, exceeding the critical water level threshold, at which residential buildings are flooded.

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Soil microbial inoculation during flood events shapes headwater stream microbial communities and diversity

Microbial Ecology ◽

10.1007/s00248-021-01700-3 ◽

2021 ◽

Author(s):

Florian Caillon ◽

Katharina Besemer ◽

Peter Peduzzi ◽

Jakob Schelker

Keyword(s):

Microbial Diversity ◽

Bacterial Diversity ◽

Soil Water ◽

Headwater Streams ◽

High Flow ◽

Low Flow ◽

Flood Events ◽

Flow Conditions ◽

Soil Microbial ◽

Microbial Inoculation

AbstractFlood events are now recognized as potentially important occasions for the transfer of soil microbes to stream ecosystems. Yet, little is known about these “dynamic pulses of microbial life” for stream bacterial community composition (BCC) and diversity. In this study, we explored the potential alteration of stream BCC by soil inoculation during high flow events in six pre-alpine first order streams and the larger Oberer Seebach. During 1 year, we compared variations of BCC in soil water, stream water and in benthic biofilms at different flow conditions (low to intermediate flows versus high flow). Bacterial diversity was lowest in biofilms, followed by soils and highest in headwater streams and the Oberer Seebach. In headwater streams, bacterial diversity was significantly higher during high flow, as compared to low flow (Shannon diversity: 7.6 versus 7.9 at low versus high flow, respectively, p < 0.001). Approximately 70% of the bacterial operational taxonomic units (OTUs) from streams and stream biofilms were the same as in soil water, while in the latter one third of the OTUs were specific to high flow conditions. These soil high-flow OTUs were also found in streams and biofilms at other times of the year. These results demonstrate the relevance of floods in generating short and reoccurring inoculation events for flowing waters. Moreover, they show that soil microbial inoculation during high flow enhances microbial diversity and shapes fluvial BCC even during low flow. Hence, soil microbial inoculation during floods could act as a previously overlooked driver of microbial diversity in headwater streams.

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Statistical and Data Mining Techniques for Understanding Water Quality Profiles in a Mining-Affected River Basin

International Journal of Agricultural and Environmental Information Systems ◽

10.4018/ijaeis.2018040101 ◽

2018 ◽

Vol 9 (2) ◽

pp. 1-19 ◽

Cited By ~ 1

Author(s):

Jose Simmonds ◽

Juan A. Gómez ◽

Agapito Ledezma

Keyword(s):

Data Mining ◽

Water Quality ◽

River Basin ◽

Suspended Solids ◽

Water Quality Monitoring ◽

High Flow ◽

Quality Monitoring ◽

Low Flow ◽

Inverse Relation

This article contains a multivariate analysis (MV), data mining (DM) techniques and water quality index (WQI) metrics which were applied to a water quality dataset from three water quality monitoring stations in the Petaquilla River Basin, Panama, to understand the environmental stress on the river and to assess the feasibility for drinking. Principal Components and Factor Analysis (PCA/FA), indicated that the factors which changed the quality of the water for the two seasons differed. During the low flow season, water quality showed to be influenced by turbidity (NTU) and total suspended solids (TSS). For the high flow season, main changes on water quality were characterized by an inverse relation of NTU and TSS with electrical conductivity (EC) and chlorides (Cl), followed by sources of agricultural pollution. To complement the MV analysis, DM techniques like cluster analysis (CA) and classification (CLA) was applied and to assess the quality of the water for drinking, a WQI.

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The Impacts of Land Use Patterns on Water Quality in a Trans-Boundary River Basin in Northeast China Based on Eco-Functional Regionalization

International Journal of Environmental Research and Public Health ◽

10.3390/ijerph15091872 ◽

2018 ◽

Vol 15 (9) ◽

pp. 1872 ◽

Cited By ~ 7

Author(s):

Peixuan Cheng ◽

Fansheng Meng ◽

Yeyao Wang ◽

Lingsong Zhang ◽

Qi Yang ◽

...

Keyword(s):

Water Quality ◽

Land Use ◽

River Basin ◽

Natural Environment ◽

Flow Region ◽

High Flow ◽

Land Use Patterns ◽

Use Patterns ◽

The Impact ◽

Degraded Water Quality

The relationships between land use patterns and water quality in trans-boundary watersheds remain elusive due to the heterogeneous natural environment. We assess the impact of land use patterns on water quality at different eco-functional regions in the Songhua River basin during two hydrological seasons in 2016. The partial least square regression indicated that agricultural activities associated with most water quality pollutants in the region with a relative higher runoff depth and lower altitude. Intensive grazing had negative impacts on water quality in plain areas with low runoff depth. Forest was related negatively with degraded water quality in mountainous high flow region. Patch density and edge density had major impacts on water quality contaminants especially in mountainous high flow region; Contagion was related with non-point source pollutants in mountainous normal flow region; landscape shape index was an effective indicator for anions in some eco-regions in high flow season; Shannon’s diversity index contributed to degraded water quality in each eco-region, indicating the variation of landscape heterogeneity influenced water quality regardless of natural environment. The results provide a regional based approach of identifying the impact of land use patterns on water quality in order to improve water pollution control and land use management.

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Prompt Leak Detection for High Pressure Feedwater Heaters

2002 International Joint Power Generation Conference ◽

10.1115/ijpgc2002-26140 ◽

2002 ◽

Cited By ~ 1

Author(s):

Steven A. Kidwell

Keyword(s):

High Pressure ◽

Local Level ◽

High Flow ◽

First Year ◽

Collateral Damage ◽

Flow Conditions ◽

Unit Load ◽

Single Tube ◽

Drain Flow ◽

High Level

I. THE NEED. A. In high pressure feedwater heaters, a tube leak quickly claims several neighboring tubes as collateral victims. B. Prompt detection of the initial leak would save the neighboring tubes from damage and preclude a potential turbine water induction incident. II. EXAMPLE. A. A Midwest generating station replaced 12 old high pressure heaters. The new heaters contained 304N SS tubes. In one of the new heaters, an unknown localized contaminant caused a single tube leak within the first year. This single leak went undetected until several surrounding tubes were lost due to impingement from the initial leak. And even the conservatively sized normal and emergency drains were overwhelmed, causing the heater to trip on high level. III. CAPABILITY OF SMART LEVEL CONTROLS. A. There are three known possibilities that would cause high drain-flow conditions in a feedwater heater. 1. High Unit Load. 2. The upstream feedwater heater is out of service. 3. A tube leak. B. Traditional Local level controls can sense high flow conditions, but cannot tell why. Most systems will alarm the opening of the emergency drain valve, but by that time, the collateral tube damage is usually severe. “Smart” Level Controls have the capability to distinguish between these conditions, thus allowing it to give early notification of a tube leak, before collateral damage becomes severe.

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