Periodically hydrologic alterations decouple the relationships between physicochemical variables and chlorophyll-a in a dam-induced urban lake

Abstract: Aim This article deals with the estimation of a model for CO2 emissions in the Hidrosogamoso reservoir based on the organic matter level and water quality. This is in order to determine the impact of the creation of a tropical reservoir on the generation of greenhouse gases (GHG), and to establish the water quality and emissions dynamics. We hypothesize that the spatial variability of emissions is determined by water quality and carbon cycling in water. Methods Multivariate techniques were applied to determine the relationships between CO2 and certain physicochemical variables measured in the reservoir between February and May 2015, taking samples in 10 stations and measuring 14 variables (water quality parameters and CO2). Factor, cluster, discriminant and regression analysis, as well as the geostatistical technique kriging, were used. Results We observed that all variables except dissolved organic carbon have strong linear relationships. Nitrate, total-P, total solids and total suspended solids are related due to the presence of nutrients in the water; chlorophyll a and biodegradable dissolved organic carbon due to organic carbon; and alkalinity and dissolved solids due to dissolved minerals. The sampling stations can be classified into two homogeneous groups. The first consists of the stations peripheral to the reservoir and the second of stations inside the reservoir. This difference is due mainly to the behavior of chlorophyll a and biodegradable dissolved organic carbon, and these two variables are also the best predictors for CO2, with a maximum adjustment of 70%. Conclusions Our main conclusion is that the production of CO2 is due to decomposition of flooded organic carbon, depends on the soils flooded and the tributary water quality, and that the production of this gas will, based on the literature, continue for 5 to 10 years depending on the nature of the forest flooded.

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The Effects of Limiting Restoration Treatments in a Shallow Urban Lake

Water ◽

10.3390/w12051383 ◽

2020 ◽

Vol 12 (5) ◽

pp. 1383

Author(s):

Katarzyna Kowalczewska-Madura ◽

Joanna Rosińska ◽

Renata Dondajewska-Pielka ◽

Ryszard Gołdyn ◽

Lech Kaczmarek

Keyword(s):

Water Quality ◽

Chlorophyll A ◽

Municipal Wastewater ◽

Cyanobacterial Blooms ◽

Urban Lake ◽

Low Oxygen ◽

Gradual Improvement ◽

Chlorophyll A Concentration ◽

Phosphorus Inactivation ◽

Bottom Zone

Swarzędzkie Lake, directly polluted for many years with municipal wastewater and heavily loaded with nutrient compounds from the catchment area, has become degraded and strongly eutrophicated. Strong cyanobacterial blooms have contributed, among others, to the cessation of recreational use of this urban lake. Its sustainable restoration was started in autumn 2011. These treatments were a combination of three complementary methods: aeration with a pulverizing aerator, phosphorus inactivation with small doses of magnesium chloride and iron sulphate (<15 kg ha−1) and biomanipulation. These treatments were carried out for three years (2012–2014), and in the next two (2015–2016), treatments were limited from three to one method—aeration. The obtained effects (a decrease in the number of cyanobacteria in phytoplankton and at the same time an increase in its biodiversity, decrease in chlorophyll a concentration and improvement of transparency) were lost due to the cessation of phosphorus inactivation and biomanipulation. The biological balance was upset, which resulted in an increase in chlorophyll a concentration, the return of cyanobacteria dominance in the phytoplankton and a deterioration of water quality. Leaving only a pulverizing aerator active, to maintain low oxygen concentrations near the bottom zone was not sufficient to ensure a gradual improvement of water quality with quite a significant external load of nutrients.

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Rapid field estimation of biochemical oxygen demand in a subtropical eutrophic urban lake with chlorophyll a fluorescence

Environmental Monitoring and Assessment ◽

10.1007/s10661-014-4171-1 ◽

2014 ◽

Vol 187 (1) ◽

Cited By ~ 3

Author(s):

Zhen Xu ◽

Y. Jun Xu

Keyword(s):

Chlorophyll A ◽

Biochemical Oxygen Demand ◽

Chlorophyll A Fluorescence ◽

Oxygen Demand ◽

Urban Lake ◽

Field Estimation

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Risk Assessment of Urban Lake Water Quality Based on in-situ Cyanobacterial and Total Chlorophyll-a Monitoring

Polish Journal of Environmental Studies ◽

10.15244/pjoes/60895 ◽

2016 ◽

Vol 25 (2) ◽

pp. 655-661 ◽

Cited By ~ 6

Author(s):

Hazem Kalaji ◽

Oksana Sytar ◽

Marian Brestic ◽

Izabela Samborska ◽

Magdalena Cetner ◽

...

Keyword(s):

Water Quality ◽

Risk Assessment ◽

Chlorophyll A ◽

Lake Water ◽

Total Chlorophyll ◽

Urban Lake ◽

Lake Water Quality

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ESTUDO DA MITIGAÇÃO DA EUTROFIZAÇÃO DO AÇUDE VELHO PELA ELETRÓLISE

Eclética Química Journal ◽

10.26850/1678-4618eqj.v39.1.2014.p107-119 ◽

2014 ◽

Vol 39 (1) ◽

pp. 107

Author(s):

Luciano Nascimento ◽

Lourdes Cristina Lucena Agostinho ◽

Bernadete F. Cavalcanti

Keyword(s):

Chlorophyll A ◽

Nitrate Removal ◽

Urban Lake ◽

Anaerobic Conditions ◽

Algae Bloom ◽

Eutrophic Lakes ◽

Aluminum Sheets ◽

Physical Chemical ◽

Sampling Points ◽

Lakes And Reservoirs

In eutrophic lakes and reservoirs the green – blue algae bloom contributes to increase the chlorophyll “a” concentration, deteriorates the water quality with anaerobic conditions in the deepest waters and provokes scum formation among other impacts. Due to the occurrence of irregular nitrification events in the waters of the polluted urban lake, Açude Velho which is located in Campina Grande, PB during the dry season, it was analyzed the performance of the electrolytic process in treating these waters. For the electrolysis treatment it was built, in laboratory scale, a 2 liters reactor where it was inserted an electrolytical assemblage made of steel and aluminum sheets. Samples were obtained in eight sampling points in the lake. The following physical, chemical and organic parameters were obtained: color, turbidity, pH, Alkalinity, calcium, chloride, nitrate, total phosphorus and chlorophyll “a”. After 15 minutes of electrolysis, it was applied 45 minutes of sedimentation to the effluent. The results showed that the alumen production by ion pairing with the water sulphate concentration provoked the water impurities flotation. It was also observed a total denitrification (100% nitrate removal) with N2 liberation to the environment. Phosphorus and chlorophyll “a” removal was also significant.

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High-Resolution electron crystallography of the light-harvesting chlorophyll-a/b protein complex from chloroplast membranes

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100181816 ◽

1990 ◽

Vol 48 (1) ◽

pp. 610-610

Author(s):

Werner Kühlbrandt ◽

Da Neng Wang ◽

K.H. Downing

Keyword(s):

High Resolution ◽

Electron Diffraction ◽

Chlorophyll A ◽

Protein Complex ◽

Structural Integrity ◽

Light Harvesting ◽

Lhc Ii ◽

Diffraction Patterns ◽

Difference Fourier ◽

2D Crystals

The light-harvesting chlorophyll-a/b protein complex (LHC-II) is the most abundant membrane protein in the chloroplasts of green plants where it functions as a molecular antenna of solar energy for photosynthesis. We have grown two-dimensional (2d) crystals of the purified, detergent-solubilized LHC-II . The crystals which measured 5 to 10 μm in diameter were stabilized for electron microscopy by washing with a 0.5% solution of tannin. Electron diffraction patterns of untilted 2d crystals cooled to 130 K showed sharp spots to 3.1 Å resolution. Spot-scan images of 2d crystals were recorded at 160 K with the Berkeley microscope . Images of untilted crystals were processed, using the unbending procedure by Henderson et al . A projection map of the complex at 3.7Å resolution was generated from electron diffraction amplitudes and high-resolution phases obtained by image processing .A difference Fourier analysis with the same image phases and electron diffraction amplitudes recorded of frozen, hydrated specimens showed no significant differences in the 3.7Å projection map. Our tannin treatment therefore does not affect the structural integrity of the complex.

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