Limnological effects of a large Amazonian run-of-river dam on the main river and drowned tributary valleys

AbstractRun-of-river dams are often considered to have lower environmental impacts than storage dams due to their smaller reservoirs and low potential for flow alteration. However, this has been questioned for projects recently built on large rivers around the world. Two of the world’s largest run-of-river dams—Santo Antônio and Jirau—were recently constructed on the Madeira River, a major tributary to the Amazon River in Brazil. Here we evaluate the effects of the creation of the Santo Antônio dam on the water chemistry and thermal structure of the Madeira River mainstem and back-flooded valleys of tributaries within the reservoir inundated area. In contrast to the mainstem river, some back-flooded tributaries periodically developed thermal stratification, which is associated with higher water residence times. Additionally, biochemical oxygen demand, partial pressure of CO2, and organic carbon all increased in the tributary valleys inundated by the reservoir, possibly due to increased input of allochthonous organic matter and its subsequent mineralization upon back-flooding—a common feature of newly flooded impoundments. The mainstem did not show detectable dam-related changes in water chemistry and thermal structure. Although the majority of the reservoir area maintained riverine conditions, the lateral valleys formed upon back-flooding—corresponding to ~30% of the Santo Antônio reservoir area—developed lake-like conditions akin to a typical reservoir of a storage dam.

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Assessment of the physicochemical variables of a subtropical reservoir in the northwest of Argentina

Acta Limnologica Brasiliensia ◽

10.1590/s2179-975x2014000400005 ◽

2014 ◽

Vol 26 (4) ◽

pp. 367-380 ◽

Cited By ~ 2

Author(s):

Beatriz Concepción Tracanna ◽

Silvia Nelly Martínez De Marco ◽

María de los Ángeles Taboada ◽

Virginia Mirande ◽

María de Lourdes Gultemirian ◽

...

Keyword(s):

Dissolved Oxygen ◽

Physicochemical Parameters ◽

Thermal Stratification ◽

Oxygen Demand ◽

Limiting Factor ◽

Alkaline Ph ◽

A Value ◽

Sodium Calcium ◽

Calcium Bicarbonate ◽

Laboratory Results

AIM: The Escaba dam is located in the south of the Tucumán province, Argentina, at 650 m above sea level. It has an extension of 541 ha. and a depth of 65 m and its tributaries are the Chavarría, Las Moras, El Chorro and Singuil rivers. The climate is mild with dry winters and rainy summers. The objective of this study was to characterize physicochemical parameters in the limnetic zone of the dam and the mouths of the tributaries to determine the water quality. METHODS: Seasonal sampling was carried out between August 2010 and May 2012. Temperature, transparency, pH and electrical conductivity were field measured, whereas dissolved oxygen, biochemical oxygen demand (BOD5), major ion constituents and nitrogen and phosphate compounds were analyzed at the laboratory. RESULTS: The water was classified as sodium-calcium-bicarbonate with neutral to alkaline pH, and thermal stratification during spring and summer. The water assayed was well oxygenated except for the bottom of the limnetic zone during the summer months. Lowest transparency was measured in the El Chorro River in November 2011 (0.12 m) and highest degree of transparency in the Singuil River during the winter of 2010 (4.1 m). The waters assayed showed weak mineralization with conductivities between 83 and 218 µS.cm-1. Maximum BOD5 value (183 mg.L-1) was measured in the Singuil River in spring 2010. Highest values for the different nitrogen compounds were as follows: 7 mg NO3-.L-1 at the bottom of the limnetic zone in August 2010, 0.07 mg NO2-.L-1 in the Las Moras River in May 2011 and 1.8 mg NH4+.L-1 in the Chavarría River in March 2011. During the summer of 2012 orthophosphate reached a value of 0.22 mg.L-1 at the bottom of the limnetic zone. The TN/TP ratio revealed that phosphate was generally the limiting factor and rarely nitrogen. CONCLUSIONS: Considering the TN, TP and transparency parameters the ecosystem was classified as hypertrophic. PCA allowed a seasonal differentiation of the sites, and components 1 and 2 classified the samples according to nutrient gradient, dissolved oxygen, BOD5 and temperature.

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Impact of climate change on Cannonsville Reservoir thermal structure in the New York City water supply

Water Quality Research Journal ◽

10.2166/wqrjc.2012.020 ◽

2012 ◽

Vol 47 (3-4) ◽

pp. 389-405 ◽

Cited By ~ 11

Author(s):

N. R. Samal ◽

D. C. Pierson ◽

E. Schneiderman ◽

Y. Huang ◽

J. S. Read ◽

...

Keyword(s):

Thermal Stratification ◽

Thermal Structure ◽

Meteorological Data ◽

Circulation Model ◽

Future Climate ◽

Structure Stability ◽

Climate Scenarios ◽

Climate Data ◽

Coupled Models ◽

Baseline Conditions

Global Circulation Model values of mean daily air temperature, wind speed and solar radiation for the 2081–2100 period are used to produce change factors that are applied to a 39 year record of local meteorological data to produce future climate scenarios. These climate scenarios are used to drive two separate, but coupled models: the Generalized Watershed Loading Functions-Variable Source Area model in order to simulate reservoir tributary inflows, and a one-dimensional reservoir hydrothermal model used to evaluate changes in reservoir thermal structure in response to changes in meteorological forcing and changes in simulated inflow. Comparisons between simulations based on present-day climate data (baseline conditions) and future simulations (change-factor adjusted baseline conditions) are used to evaluate the development and breakdown of thermal stratification, as well as a number of metrics that describe reservoir thermal structure, stability and mixing. Both epilimnion and hypolimnion water temperatures are projected to increase. Indices of mixing and stability show changes that are consistent with the simulated changes in reservoir thermal structure. Simulations suggest that stratification will begin earlier and the reservoir will exhibit longer and more stable periods of thermal stratification under future climate conditions.

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Temporal fish community responses to two cascade run-of-river dams in the Madeira River, Amazon basin

Ecohydrology ◽

10.1002/eco.1889 ◽

2017 ◽

Vol 10 (8) ◽

pp. e1889 ◽

Cited By ~ 16

Author(s):

Ariana Cella-Ribeiro ◽

Carolina Rodrigues da Costa Doria ◽

Jynessa Dutka-Gianelli ◽

Hellison Alves ◽

Gislene Torrente-Vilara

Keyword(s):

Fish Community ◽

Amazon Basin ◽

Community Responses ◽

Madeira River ◽

Run Of River

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Thermal stratification and fish thermal preference explain vertical eDNA distributions in lakes

10.1101/2020.04.21.042820 ◽

2020 ◽

Cited By ~ 1

Author(s):

Joanne E. Littlefair ◽

Lee E. Hrenchuk ◽

Paul J. Blanchfield ◽

Michael D. Rennie ◽

Melania E. Cristescu

Keyword(s):

Thermal Stratification ◽

Lake Trout ◽

Cold Water ◽

Thermal Structure ◽

Spatial Scales ◽

Habitat Preferences ◽

Environmental Dna ◽

Temporal And Spatial Distribution ◽

Lake Ecosystems ◽

Animal Habitat

AbstractSignificant advances have been made towards surveying animal and plant communities using DNA isolated from environmental samples. Despite rapid progress, we lack a comprehensive understanding of the “ecology” of environmental DNA (eDNA), particularly its temporal and spatial distribution and how this is shaped by abiotic and biotic processes. Here, we tested how seasonal variation in thermal stratification and animal habitat preferences influence the distribution of eDNA in lakes. We sampled eDNA depth profiles of five dimictic lakes during both summer stratification and autumn turnover, each containing warm- and cool-water fishes as well as the cold-water stenotherm, lake trout (Salvelinus namaycush). Habitat use by lake trout was validated by acoustic telemetry and was significantly related to eDNA distribution during stratification. Fish eDNA became “stratified” into layers during summer months, reflecting lake stratification and the thermal niches of the species. During summer months, lake trout, which rarely ventured into shallow waters, could only be detected at the deepest layers of the lakes, whereas the eDNA of warm-water fishes was much more abundant above the thermocline. By contrast, during autumn lake turnover, the fish species assemblage as detected by eDNA was homogenous throughout the water column. These findings contribute to our overall understanding of the “ecology” of eDNA within lake ecosystems, illustrating how the strong interaction between seasonal thermal structure in lakes and thermal niches of species on very localised spatial scales influences our ability to detect species.

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Dynamics of Hg and MeHg in the Madeira River basin (Western Amazon) before and after impoundment of a run-of-river hydroelectric dam

Environmental Research ◽

10.1016/j.envres.2020.109896 ◽

2020 ◽

Vol 189 ◽

pp. 109896 ◽

Cited By ~ 2

Author(s):

Wanderley R. Bastos ◽

José G. Dórea ◽

Luiz D. Lacerda ◽

Ronaldo Almeida ◽

Walkimar Aleixo Costa-Junior ◽

...

Keyword(s):

River Basin ◽

Hydroelectric Dam ◽

Before And After ◽

Madeira River ◽

Madeira River Basin ◽

Run Of River

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Multiyear Links between Water Chemistry, Algal Chlorophyll, Drought-Flood Regime, and Nutrient Enrichment in a Morphologically Complex Reservoir

International Journal of Environmental Research and Public Health ◽

10.3390/ijerph17093139 ◽

2020 ◽

Vol 17 (9) ◽

pp. 3139 ◽

Cited By ~ 2

Author(s):

Jang HaRa ◽

Usman Atique ◽

Kwang-Guk An

Keyword(s):

Water Quality ◽

Water Chemistry ◽

Flood Control ◽

Trophic Status ◽

Oxygen Demand ◽

Drought Severity ◽

Domestic Water ◽

Chl A ◽

Drought And Flood ◽

The Impact

This investigation targeted the largest morphologically complex reservoir (Soyang) in South Korea during 1992–2013. It is a prominent source of domestic water supply, irrigation, flood control, and hydroelectric power generation. Therefore, this investigation focused on regional- to global-scale applications. We revealed the empirical links between chlorophyll (Chl-a) and total nitrogen (TN) and total phosphorus (TP), the impact of the monsoon regime on nutrients, and flood and drought regime. Further, we investigated the trophic status dynamics, tendencies of water chemistry factors, and valuation of zonal water chemistry by the application of a modified multimetric water pollution index (WPI). The physicochemical indicators illustrated significant disparities among the Lacustrine (Lz), Transition (Tz), and Riverine (Rz) zones. The solid contents (TSS) displayed a significant increase in the lake zones in the order of Lz (4.58 ± 13.7 mg/L), Tz (6.16 ± 16.2 mg/L), and Rz (7.38 ± 18.9 mg/L). However, TP and allied chemical species revealed an inverse relationship with the TN:TP ambient ratios. Nevertheless, Chl-a displayed sharp interzonal fluctuations from the Lz (2.90 ± 3.29 µg/L) to Tz (4.61 ± 4.98 µg/L). The seasonal deviations, however, exposed divergent heterogeneities among the TSS, TN, TP, and Chl-a. The regression plot between the observed and predicted Chl-a in the Soyang reservoir displayed a very strong relationship (R2 = 0.997). The seasonal and interannual variations of trophic status displayed a higher impact of precipitation, particularly in the case of TP and Chl-a. The flood years indicated phosphorus limitations, while drought years alluded to the non-algal light limitations (biogenic turbidity). Water temperature (WT), dissolved oxygen (DO), biological oxygen demand (BOD), TSS, TP, and Chl-a displayed decreasing trends in the ambient water. In contrast, pH, chemical oxygen demand (COD), electrical conductivity (EC), and TN displayed increasing tendencies by the application Mann–Kendall trend analysis. The WPI outcomes designated Lz with excellent water quality while Tz an Rz indicated good water quality. It also indicated impending sedimentation tendencies in the Rz. In conclusion, our findings indicated fluctuating rainfall patterns (drought and flood conditions) that significantly impacted the Soyang reservoir water quality, flood and drought severity, and trophic status of the reservoir. This study highlights the requirements of further studies to substantiate the drought and flood dynamics and their impacts on nutrients and overall water quality status.

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Urbanization plays a minor role in the flooding and surface water chemistry of Puerto Rico’s mangroves

10.1101/423434 ◽

2018 ◽

Cited By ~ 2

Author(s):

Benjamin L. Branoff

Keyword(s):

Puerto Rico ◽

Surface Water ◽

Land Cover ◽

Water Chemistry ◽

Oxygen Demand ◽

Minor Role ◽

Urban Landscapes ◽

Surface Water Chemistry ◽

Mangrove Hydrology ◽

Urban Sites

ABSTRACTAlthough hydrology and water chemistry are known to change in proximity to cities, there remains little empirical evidence connecting specific components of urban landscapes to mangrove flooding dynamics or surface water chemistry. This study constructs five-year water level models from tidal harmonics and precipitation inputs to characterize mangrove flooding across urban gradients in three watersheds of Puerto Rico. There was some evidence for an influence of urbanization on both flooding and water chemistry, but this depended on the definition of urbanness, and points instead to geomorphology as the primary culprit. Urban sites exhibited 46% longer hydroperiods and 450% lower depths than non-urban sites. Rainfall importance was explained more by geomorphology than by urbanization and suggested systems with limited tidal connectivity are four times more sensitive to rainfall than systems with full tidal connectivity. There was also evidence for changes in tidal amplitudes along the urban gradient, which may explain the observed differences in flooding. Relationships between surface water chemical metrics and land cover contradicted previous studies by suggesting lower nutrients and biochemical oxygen demand with increasing urbanization. These results reinforce the understanding that the most important drivers of urban mangrove hydrology and water quality in Puerto Rico are likely geomorphology and tidal connectivity, with little but not zero influence from surrounding land cover. Results should be considered alongside the reported errors stemming from inaccuracies in digital elevation and rainfall response models, and will be useful in understanding future ecological censuses on the island.

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Self-Organization of Atmospheric Macroturbulence into Critical States of Weak Nonlinear Eddy–Eddy Interactions

Journal of the Atmospheric Sciences ◽

10.1175/jas3699.1 ◽

2006 ◽

Vol 63 (6) ◽

pp. 1569-1586 ◽

Cited By ~ 111

Author(s):

Tapio Schneider ◽

Christopher C. Walker

Keyword(s):

Surface Temperature ◽

Thermal Stratification ◽

Nonlinear Models ◽

Thermal Structure ◽

Baroclinic Instability ◽

Temperature Gradients ◽

Tropopause Height ◽

Weakly Nonlinear ◽

Critical States ◽

Inverse Energy Cascade

Abstract It is generally held that atmospheric macroturbulence can be strongly nonlinear. Yet weakly nonlinear models successfully account for scales and structures of baroclinic eddies in Earth's atmosphere. Here a theory and simulations with an idealized GCM are presented that suggest weakly nonlinear models are so successful because atmospheric macroturbulence organizes itself into critical states of weak nonlinear eddy–eddy interactions. By modifying the thermal structure of the extratropical atmosphere such that its supercriticality remains limited, macroturbulence inhibits nonlinear eddy–eddy interactions and the concomitant inverse energy cascade from the length scales of baroclinic instability to larger scales. For small meridional surface temperature gradients, the extratropical thermal stratification and tropopause height are set by radiation and convection, and the supercriticality is less than one; for sufficiently large meridional surface temperature gradients, the extratropical thermal stratification and tropopause height are modified by baroclinic eddies such that the supercriticality does not significantly exceed one. In either case, the scale of the energy-containing eddies is similar to the scale of the linearly most unstable baroclinic waves, and eddy kinetic and available potential energies are equipartitioned. The theory and simulations point to fundamental constraints on the thermal structures and global circulations of the atmospheres of Earth and other planets, for example, by providing limits on the tropopause height and estimates for eddy scales, eddy energies, and jet separation scales.

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