Trends in planktonic copepod diversity in reservoirs and lotic stretches in a large river basin in South America

2014 ◽  
Vol 65 (8) ◽  
pp. 727 ◽  
Author(s):  
Gilmar Perbiche-Neves ◽  
Geoffrey A. Boxshall ◽  
Marcos G. Nogueira ◽  
Carlos E. F. da Rocha
Keyword(s):  
Species Richness ◽  
South America ◽  
River Basin ◽  
Retention Time ◽  
Water Retention ◽  
Negative Impact ◽  
High Water ◽  
Large River ◽  
Copepod Species ◽  
Water Retention Time

Copepod assemblages were analysed across La Plata River basin, the second largest in South America. High values of species richness and Shannon–Wiener diversity were found in the lower Paraná River, the main and largest river of the basin, and in eutrophic reservoirs located in the upper basin. The species richness was negatively correlated with turbidity, probably because of the negative impact on filtration rates in calanoids. There was a trend of decreasing richness correlated with high water flow in reservoirs with short water-retention time (<40 days) and simple morphometric shape, and also in deeper oligo-mesotrophic reservoirs with very long water-retention time and dendritic shape (variables that occurred in combination in the present study). The number of copepod species (46) found in our study is only about half of the gamma diversity estimated using Jack1 non-parametric analysis for the basin (86 species). There are groups of copepod species typical of reservoirs and rivers, and others that can occur in both of these habitat types. Reservoir and lentic species are favoured by a deeper water column, higher temperatures and higher transparency, whereas the opposite is the case of typical riverine species. There is also a group of species that occur in both sets of conditions.

The effects of water retention time and watershed features on the limnology of two tropical reservoirs in Brazil

2008 ◽  
Vol 13 (4) ◽  
pp. 257-269 ◽  
Author(s):  
Maria Carolina S. Soares ◽  
Marcelo M. Marinho ◽  
Vera L. M. Huszar ◽  
Christina W. C. Branco ◽  
Sandra M. F. O. Azevedo
Keyword(s):  
Retention Time ◽  
Water Retention ◽  
Tropical Reservoirs ◽  
Water Retention Time

scholarly journals Experiment in infiltration studies as a water treatment process

2018 ◽  
Vol 59 ◽  
pp. 00015
Author(s):  
Sylwia Kołaska ◽  
Joanna Jeż-Walkowiak ◽  
Zbysław Dymaczewski
Keyword(s):  
Water Treatment ◽  
Temperature Variation ◽  
Retention Time ◽  
Research Methodology ◽  
Water Retention ◽  
Treatment Process ◽  
Water Infiltration ◽  
Infiltration Process ◽  
Water Treatment Process ◽  
Water Retention Time

This article contains the concept of research methodology of the water infiltration process. The described research was conducted at Dębina intake in Poznan, Poland. Based on the temperature variation curves, it was possible to determine the water retention time in the ground during the flow of water from the infiltration pond through piezometers to the collecting well

scholarly journals Morphometry Dynamical of Siombak Lake, Medan Indonesia

Omni-Akuatika ◽  
2017 ◽  
Vol 13 (2) ◽  
Author(s):  
Ahmad Muhtadi ◽  
Zulham Apandy Harahap ◽  
Rusdi Leidonald
Keyword(s):  
Physical Characteristic ◽  
Retention Time ◽  
Water Retention ◽  
Average Depth ◽  
Lake Morphometry ◽  
Dynamical Study ◽  
Maximum Width ◽  
Lake Volume ◽  
First Impression ◽  
Water Retention Time

Siombak lake (28 ha area) was a salty lake located in Medan coastal, Indonesia. Water fluctuation influenced by the sea tide. Therefore, it needed to do morphometry dynamical study as the first impression of lake physical characteristic. The purpose of this study was to understand the dynamical of Siombak lake morphometry. The research was done in September 2016. Lake mapping was done by making 100 line zig zag and draw with ArcMap. Bathymetry showed that the bottom of the lake was sloping at the center part of west and southeast of the lake, and steeping at north, south and east. Siombak Lake has shoreline length 2,535.78 m, with SDI value 2.70. Maximum length 756 m, with maximum width 246.15 m. Lake maximum depth was 17.7 m at MSL, 18.98 m at highest tide and 16.71 m at lowest tide, with average depth 5.33 m at MSL, 6.30 m at highest tide and 4.30 m at lowest tide. Lake volume was 783,607.16 m3 at MSL, 829,395.52 m3 at highest tide and 355,544.14 m3 at lowest tide, with water debit around 32.50 – 50.17 m3s-1. Water retention time was ± 4.33 – 6.75 hours

Riverine water transformation during retention in small lowland reservoirs

2009 ◽  
Vol 38 (4) ◽  
Author(s):  
Tomasz Suchowolec ◽  
Andrzej Górniak
Keyword(s):  
Retention Time ◽  
Water Retention ◽  
Riverine Water ◽  
Dam Reservoirs ◽  
Water Retention Time ◽  
Lowland Reservoirs ◽  
Northeastern Poland ◽  
Phosphorus Sedimentation ◽  
Almost All ◽  
Phosphorus Reduction

Riverine water transformation during retention in small lowland reservoirsSix small dam reservoirs in northeastern Poland, with different hydrologic and catchment characteristics were selected for research from March to October (2001-2003). There was a significant correlation between DOC and TP in the reservoirs and the water retention time (WRT). The highest values of electrical conductivity (EC) were recorded in reservoirs with an agricultural basin. In almost all reservoirs a statistically significant decrease of EC, compared to inflowing waters, was noted. Nitrates were substantially reduced in afforested catchment reservoirs. The highest TP concentration was recorded in a newly flooded reservoir. In reservoirs with long retention time, phosphorus sedimentation takes place more intensively. This caused phosphorus reduction in outflowing waters.

scholarly journals A Novel Statistical Model for Water Age Estimation in Water Distribution Networks

2015 ◽  
Vol 2015 ◽  
pp. 1-9 ◽  
Author(s):  
Wei-ping Cheng ◽  
En-hua Liu ◽  
Jing-qing Liu
Keyword(s):  
Statistical Model ◽  
Retention Time ◽  
Water Distribution ◽  
Water Retention ◽  
Distribution Networks ◽  
Water Distribution Networks ◽  
Residual Chlorine ◽  
Water Age ◽  
Important Indicator ◽  
Water Retention Time

The water retention time in the water distribution network is an important indicator for water quality. The water age fluctuates with the system demand. The residual chlorine concentration varies with the water age. In general, the concentration of residual chlorine is linearly dependent on the water demand. A novel statistical model using monitoring data of residual chlorine to estimate the nodal water age in water distribution networks is put forward in the present paper. A simplified two-step procedure is proposed to solve this statistical model. It is verified by two virtual systems and a practical application to analyze the water distribution system of Hangzhou city, China. The results agree well with that from EPANET. The model provides a low-cost and reliable solution to evaluate the water retention time.

Regulation of the abundance and turnover of copepod species by temperature, turbidity and habitat type in a large river basin

2015 ◽  
Vol 40 (6) ◽  
pp. 718-725 ◽  
Author(s):  
Gilmar Perbiche-Neves ◽  
Geoffrey Allan Boxshall ◽  
Daniel Previattelli ◽  
Danilo Augusto Oliveira Naliato ◽  
Marcio Roberto Pie ◽  
...  
Keyword(s):  
River Basin ◽  
Habitat Type ◽  
Large River ◽  
Copepod Species

Influence of pine bark and gravel on degradation of isoxaben in retention basins

Weed Science ◽  
2004 ◽  
Vol 52 (1) ◽  
pp. 158-165 ◽  
Author(s):  
Gretchen L. Jameson ◽  
Jeanne A. Briggs ◽  
Ted Whitwell ◽  
R. Thomas Fernandez ◽  
Melissa B. Riley
Keyword(s):  
Retention Time ◽  
Water Retention ◽  
Field Studies ◽  
Pine Bark ◽  
Runoff Water ◽  
Time Treatment ◽  
Model Flow ◽  
Water Retention Time ◽  
Retention Basins ◽  
Flow Through

Herbicides applied to container plants in nurseries are transported in runoff water to on- and off-site ponds and retention basins. This study was conducted to determine biotic and abiotic effects on isoxaben dissipation in model flow-through retention basins to maximize aqueous isoxaben degradation. Field studies were conducted in 1999 and 2000 to evaluate the effects of gravel and pine bark amendments and water retention times on isoxaben persistence in holding basins. In 1999, total isoxaben discharge into flow-through gravel-filled basins was greater than isoxaben losses from gravel and nongravel basins in which water was retained. Photodegradation appeared to be greater in basins without gravel, indicating that gravel protected isoxaben from photolysis. Further studies determined the effect of water retention time and the presence of aged pine bark amendment on isoxaben discharge from basins. Isoxaben discharge level was reduced when water retention time was increased from 3 to 5 d. In the 3-d retention time treatment, added pine bark reduced peak isoxaben discharge by 45% and total isoxaben by 53% at 14 d after treatment. In treatments containing pine bark within the retention basins, isoxaben was released over a longer period of time. No differences were observed in 5-d water retention time treatments with and without pine bark. Analysis of gravel from isoxaben-treated retention basins indicated the presence of several genera of bacteria includingPseudomonas, Arthrobacter, andCellulomonas. Some isolates ofPseudomonas, Rahnella, Methobacterium, andPaenibacillusfrom the basins grew on M9 medium with isoxaben as the sole carbon and energy source, indicating their ability to metabolize isoxaben. Results indicate that retention basins are helpful in reducing isoxaben levels before release or reuse of runoff water from a container nursery, and that retention time of runoff water in basins is the most important factor in reducing isoxaben discharge.

Phytoplankton structure in two contrasting cascade reservoirs (Paranapanema River, Southeast Brazil)

Biologia ◽  
2011 ◽  
Vol 66 (6) ◽  
Author(s):  
Gilmar Perbiche-Neves ◽  
Rosa Ferreira ◽  
Marcos Nogueira
Keyword(s):  
Retention Time ◽  
Environmental Variables ◽  
Water Retention ◽  
Major Influence ◽  
Storage Reservoir ◽  
Southeast Brazil ◽  
River Reservoir ◽  
Phytoplankton Structure ◽  
Water Retention Time ◽  
Run Of River

AbstractA series of eleven reservoirs was constructed in the Paranapanema River, southeast Brazil, for hydropower production. The phytoplankton structure and its relations with the environmental variables were studied in two of these reservoirs: a large upstream located storage system (high water retention time) and a small run-of-river system (short water retention time). The samples were collected quarterly for two consecutive years, at four sampling stations in each reservoir. Higher phytoplankton richness was observed in the semi-lotic compartments. Higher values of diversities were observed in the upper region of the run-of-river reservoir, under the influence of the larger storage reservoir discharges, and lower values were observed in deeper layers of this same reservoir. The pronounced variation on seasonal rain precipitation and operational water releases, retention time and quota had major influence in the phytoplankton assemblages. The influence of other environmental variables was also indicated by a canonical correlation analysis. Chlamydophyceae, Dinophyceae, Zygnemaphyceae, Chrysophyceae, Chlorophyceae, Bacillariophyceae and Cyanobacteria were positively correlated with higher transparency and depth; Euglenophyceae with temperature and Cryptophyceae with total phosphorus, dissolved oxygen, conductivity, turbidity, total nitrogen and total suspended solids. The influence of the storage reservoir on the phytoplankton of the downstream run-of-river reservoir was more evident in the dry period. During the rainy period the lateral tributaries effects seems to have a higher influence, especially on the smaller studied reservoir.

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