Production by Hexagenia limbata in a warm-water reservoir and its association with chlorophyll content of the water column

Hydrobiologia ◽  
1989 ◽  
Vol 185 (3) ◽  
pp. 183-193 ◽  
Author(s):  
Cindi L. Welch ◽  
Darrell S. Vodopich
Keyword(s):  
Water Column ◽  
Chlorophyll Content ◽  
Water Reservoir ◽  
Warm Water ◽  
Hexagenia Limbata

scholarly journals Vertical and temporal dynamics of cyanobacteria in the Carpina potable water reservoir in northeastern Brazil

2011 ◽  
Vol 71 (2) ◽  
pp. 451-459 ◽  
Author(s):  
AN Moura ◽  
EW Dantas ◽  
HSB Oliveira ◽  
MC Bittencourt-Oliveira
Keyword(s):  
Water Column ◽  
Potable Water ◽  
Temporal Dynamics ◽  
Water Reservoir ◽  
Optical Microscope ◽  
Temporal Variations ◽  
Northeastern Brazil ◽  
Cyanobacterial Blooms ◽  
Cylindrospermopsis Raciborskii

This study analysed vertical and temporal variations of cyanobacteria in a potable water supply in northeastern Brazil. Samples were collected from four reservoir depths in the four months; September and December 2007; and March and June 2008. The water samples for the determination of nutrients and cyanobacteria were collected using a horizontal van Dorn bottle. The samples were preserved in 4% formaldehyde for taxonomic analysis using an optical microscope, and water aliquots were preserved in acetic Lugol solution for determination of density using an inverted microscope. High water temperatures, alkaline pH, low transparency, high phosphorous content and limited nitrogen content were found throughout the study. Dissolved oxygen stratification occurred throughout the study period whereas temperature stratification occurred in all sampling months, with the exception of June. No significant vertical differences were recorded for turbidity or total and dissolved forms of nutrients. There were high levels of biomass arising from Planktothrix agardhii, Cylindrospermopsis raciborskii, Geitlerinema amphibium and Pseudanabaena catenata. The study demonstrates that, in a tropical eutrophic environment with high temperatures throughout the water column, perennial multi-species cyanobacterial blooms, formed by species capable of regulating their position in the water column (those that have gas vesicles for buoyancy), are dominant in the photic and aphotic strata.

Unmanned arial system imaging and refined geologic modelling of the Waiwera geothermal Reservoir

2020 ◽  
Author(s):  
Melissa Präg ◽  
Ivy Becker ◽  
Thomas R. Walter ◽  
Michael Kühn
Keyword(s):  
Heat Transfer ◽  
New Zealand ◽  
Water Reservoir ◽  
Reservoir Management ◽  
Geothermal Reservoir ◽  
Reservoir Rock ◽  
Warm Water ◽  
Rock Properties ◽  
Hydrogeology Journal ◽  
First Time

<p>The utilization of geothermal reservoirs as alternative energy source is becoming increasingly important worldwide. Details of rock properties, structures, heat transfer and resulting interactions are the basis for the implementation of a sustainable reservoir management, but are often not well enough understood. The investigated warm water reservoir in Waiwera, New Zealand, has been known for many centuries. Triggered by overproduction in the third quarter of the 20th century, the reservoir pressure dropped significantly and in the 1970s the natural seeps on the beach dried up [1]. However, the shutdown of the main user's pumps (Waiwera Thermal Pools) in 2018 led to renewed temporary and location-specific artesian activity. The question now is whether the seeps on the beach will also reappear?</p><p>Hydrogeological models are the basis for a sustainable management of groundwater resources. The key point for the Waiwera reservoir is the amount of geothermal water which is permanently available. However, models are also used to describe the current hydraulic and thermal situation of the study area [2].</p><p>An expedition was carried out in 2019 to investigate the artesian activity of the reservoir, which has been observed again since 2018, and to build a new geological model. For the first time, thermal cameras carried by unmanned aerial systems (UAS) show the emergence of warm water at the beach and photogrammetric analyses carried out allow structural and lithological mapping on exposed cliffs where localized thermal anomalies were identified for the first time. The Waitemata formation found there is considered as analogue of the reservoir rock and thus serves for an improved understanding of the subsurface reservoir properties. The analyses show individual water and heat conducting lithologies and thus provide details about geological units that also constitute the geothermal reservoir at depth.</p><p>Based on the field exploration and the associated structural interpretations, a geological and thermal 3D model is now available for the first time, which will be employed to improve calibration of the hydraulic conditions of the warm water reservoir. Further, the model will be applied in the context of a sustainable reservoir management to clarify the question about the natural seeps on the beach. The reappearance of artesian activity in the Waiwera area due to significant adaptation of production rates is unique but the improved understanding of the interaction between rock properties, existing structures and heat transfer will also enable other reservoirs to be better understood.</p><p>[1] Kühn M., Stöfen H. (2005) A reactive flow model of the geothermal reservoir Waiwera, New Zealand. Hydrogeology Journal 13, 606-626</p><p>[2] Kühn M., Altmannsberger C., Hens C. (2016) Waiwera’s warm water reservoir – What is the significance of models? Grundwasser 21, 107-117</p>

Sedimentary record of water column trophic conditions and sediment carbon fluxes in a tropical water reservoir (Valle de Bravo, Mexico)

2014 ◽  
Vol 22 (6) ◽  
pp. 4680-4694 ◽  
Author(s):  
Vladislav Carnero-Bravo ◽  
Martín Merino-Ibarra ◽  
Ana Carolina Ruiz-Fernández ◽  
Joan Albert Sanchez-Cabeza ◽  
Bassam Ghaleb
Keyword(s):  
Water Column ◽  
Water Reservoir ◽  
Carbon Fluxes ◽  
Sedimentary Record ◽  
Trophic Conditions ◽  
Tropical Water ◽  
Sediment Carbon

scholarly journals Assessment of Seasonal Changes in Water Chemistry of the Ridracoli Water Reservoir (Italy): Implications for Water Management

Water ◽  
2020 ◽  
Vol 12 (2) ◽  
pp. 581 ◽  
Author(s):  
Simone Toller ◽  
Beatrice M. S. Giambastiani ◽  
Nicolas Greggio ◽  
Marco Antonellini ◽  
Ivo Vasumini ◽  
...  
Keyword(s):  
Heavy Metals ◽  
Water Quality ◽  
Water Column ◽  
Seasonal Changes ◽  
Water Resource Management ◽  
Water Reservoir ◽  
Mixing Processes ◽  
Reservoir Water ◽  
Reservoir Water Level ◽  
Anoxic Conditions

The Ridracoli artificial basin is the main water reservoir of the Emilia-Romagna region (Northeast Italy). The reservoir was made by construction of a dam on the Bidente River in 1982. It is used as the main drinking water supply of the region and for hydropower production. The physical and chemical parameterseters (temperature, pH, electrical conductivity, and dissolved oxygen) of shallow water are continuously monitored whereas vertical depth profiles of water chemical data (major anions and cations, as well as heavy metals) are available on a bimonthly base. The dataset used in this research is related to the years 2015 and 2016. Data show that the reservoir is affected by an alternation of water stratification and mixing processes due to seasonal change in water temperature, density, and the reservoir water level. In late summer and winter months, the water column is stratified with anoxic conditions at the bottom. During the spring, on the other hand, when storage is at its maximum, water recirculation and mixing occur. The reservoir is characterized by a dynamic system in which precipitation, dissolution, and adsorption processes at the bottom affect water quality along the reservoir depth column. The temperature stratification and anoxic conditions at the reservoir bottom influence the concentration and mobility of some heavy metals (i.e., Fe and Mn) and, consequently, the quality of water that reaches the treatment and purification plant. This study is relevant for water resource management of the reservoir. Assessing the seasonal changes in water quality along the reservoir water column depth is fundamental to plan water treatment operations and optimize their costs. The reservoir assessment allows one to identify countermeasures to avoid or overcome the high concentrations of heavy metals and the stratification problem (i.e., artificial mixing of the water column, new water intakes at different depths operating at different times of the year, blowers, etc.).

Distribution of polyaromatic hydrocarbons in the water column and sediments of a drinking water reservoir with respect to boating activity

1994 ◽  
Vol 28 (11) ◽  
pp. 2353-2366 ◽  
Author(s):  
Trina A. Mastran ◽  
Andrea M. Dietrich ◽  
Daniel L. Gallagher ◽  
Thomas J. Grizzard
Keyword(s):  
Drinking Water ◽  
Water Column ◽  
Polyaromatic Hydrocarbons ◽  
Water Reservoir ◽  
Drinking Water Reservoir

scholarly journals Spatiotemporal distribution of planktonic ciliates in the Kuybyshev water reservoir in the area of Klimovskaya narrowing

2021 ◽  
pp. 146-162
Author(s):  
S. V. Bykova ◽  
V. A. Andreeva
Keyword(s):  
Vertical Distribution ◽  
Water Column ◽  
Water Reservoir ◽  
Regulated River ◽  
Individual Species ◽  
Hydroelectric Power Station ◽  
Kuibyshev Reservoir ◽  
Free Living ◽  
Planktonic Ciliates ◽  
Wide Range

The paper attempts to link changes in quantitative characteristics of the community of free-living planktonic ciliates and the nature of their vertical distribution with the operation mode of the hydroelectric power station in the reservoir. Low values of the abundance (8–1,560 thousand cells / m3) and biomass (0.1–66.9 mg / m3) of ciliates in the water column, and a fairly wide range of their variation in the reservoir are probably due to the oscillatory nature of the hydrological regime in the regulated river conditions. The vertical distribution of free-living planktonic ciliates of the near-dam section of the Kuibyshev reservoir was studied at all times of the day on all days of the week. The species were distributed throughout the water column to the bottom with some preference for the surface (0–2 m) and medium (4–10 m) layers. There was no clear attachment of individual species to certain layers in the conditions of homothermy. The preference for certain horizons is due to some biological characteristics of the species (for example, peritriches on the coenobia of algae in the surface layers), departure from “blooming spots”, etc. No data in favor of vertical migrations or “turbulent transport” has yet been revealed. The influence of the weekly regime of regulation of the Zhigulevskaya HPS, in which at the end of the working week, the fluctuation amplitude of many hydrological parameters probably decreases, is manifested in an increase in the abundance and biomass of planktonic ciliates at this time.The nature of the daily change in the average ciliates abundance in the water column was the same for a variant of the community in working days and was in antiphase with the change in the community abundance on weekends, namely: the maximum number on working days and on weekends was recorded in the evening (20.00) and in the daytime (14.00), respectively.

Chlorophyll content of Plešné Lake phytoplankton cells studied with image analysis

Biologia ◽  
2006 ◽  
Vol 61 (20) ◽  
Author(s):  
Jiří Nedoma ◽  
Linda Nedbalová
Keyword(s):  
Image Analysis ◽  
Water Column ◽  
Chlorophyll Content ◽  
Phytoplankton Biomass ◽  
Conversion Factor ◽  
Single Cells ◽  
Chlorophyll Concentration ◽  
Vertical Profiles ◽  
Total Chlorophyll ◽  
Chlorophyll Autofluorescence

AbstractUsing image analysis, chlorophyll autofluorescence was measured in single cells of green alga Monoraphidium dybowskii and in filaments of cyanobacteria (Pseudanabaena sp. and Limnothrix sp.) in the vertical profile of small acidified mountain lake Plešné jezero (Plešné Lake) from May to November of 2003. Cell chlorophyll autofluorescence was converted to cell chlorophyll content using a conversion factor determined by comparing the total autofluorescence of phytoplankton in a microscope field with spectrophotometrically determined total chlorophyll concentration; the conversion factor did not differ between epilimnion (0.5 m depth) and hypolimnion (9 m depth). Vertical patterns of chlorophyll concentration and of cellular chlorophyll content depended on water column mixing: during the period of stable thermal stratification, a metalimnetic peak in total chlorophyll concentration was present and cellular chlorophyll contents in the metalimnion and hypolimnion were notably elevated compared to the surface. Monotonous vertical profiles of both total chlorophyll concentration and cell chlorophyll content were typical for the period of water column overturn. During the stratification period, hypolimnetic Monoraphidium cell chlorophyll content was on average twice as high (maximum difference 2.7-fold) compared to surface values (of 3.2–12.9 fg µm−3), while in filamentous cyanobacteria (surface cell chlorophyll content of 2.2–13.3 fg µm−3), the difference was much higher — six-fold on average, with an 11.6-fold maximum value. The values measured with image analysis in 2003 were compared to unpublished values of total phytoplankton biomass-specific chlorophyll concentrations obtained using manual phytoplankton biomass determination and spectrophotometric chlorophyll measurement in 1998 at the same locality. Good agreement was found in seasonal patterns and vertical profiles of chlorophyll between both seasons.

Formation of well-mixed warm water column in central Bohai Sea during summer: Role of high-frequency atmospheric forcing

2017 ◽  
Vol 16 (6) ◽  
pp. 945-952
Author(s):  
Weiwei Ma ◽  
Xiuquan Wan ◽  
Zhankun Wang ◽  
Yulong Liu ◽  
Kai Wan
Keyword(s):  
Water Column ◽  
High Frequency ◽  
Bohai Sea ◽  
Warm Water ◽  
Atmospheric Forcing

scholarly journals Changes in Oxygen Conditions in Pławniowice Reservoir as a Result of Restoration with Hypolimnetic Withdrawal Method

2014 ◽  
Vol 40 (2) ◽  
pp. 53-63 ◽  
Author(s):  
Maciej Kostecki
Keyword(s):  
Coordinate System ◽  
Water Column ◽  
Layer Thickness ◽  
Oxygen Concentration ◽  
Water Reservoir ◽  
Water Layer ◽  
The Third ◽  
Oxygen Conditions ◽  
Oxygen Profiles ◽  
Whole Water

Abstract The restoration of the anthropogenic Pławniowice water reservoir with the hypolimnion withdrawal method (the Olszewski's tube) began in December 2003. The decision to restore the reservoir had been taken due to its terrible condition resulting from the hypertrophy, which had been indicated by the research from the years 1993–1998. The following paper presents the results of eight-year-long research into the formation of oxygen conditions and restoration settings. They were compared with the data obtained from the research before the restoration. Positive changes were witnessed. It was showed that grasping the changes in oxygen conditions enables the comparison of oxygen profiles in the same months in subsequent years. The ratio of anoxic water layer thickness to the oxygenated layer thickness was suggested as a factor characterizing oxygen conditions. The area described with an izooxa in the xy coordinate system was suggested as a factor [O2 mg/m2] allowing researchers to understand and describe occurring changes. It was observed that the oxygen solved in water as a result of the restoration occurred in the whole water column in the third decade of July. The oxygen concentration in the hypolimnion gradually rose in May, June and July each year. It was showed that the improvement in oxygen conditions stemmed from progressing oligotrophy of the reservoir.

Sign in / Sign up

Export Citation Format

Share Document