Phosphorus dynamics in the water of tropical semiarid reservoirs in a prolonged drought period

Abstract Aim To verify the vertical distribution of phosphorus in the water and to identify the predominant forms of P in the water column for understand the phosphorus dynamics in tropical semiarid reservoirs during a prolonged drought period. Methods Two reservoirs from the semiarid region of Rio Grande do Norte were analysed during the period from May 2015 to June 2016. Were analysed: Suspended solids (SS), chlorophyll a (Chl-a), dissolved oxygen (OD) and temperature. Vertical profiles were plotted for total phosphorus (PT), total dissolved phosphorus (PTD), particulate phosphorus (PP), dissolved organic phosphorus (POD) and soluble reactive phosphorus (FRS). Results The phosphorus values distributed in the water column were high for both reservoirs, presenting the highest values during the periods with lower depth. Gargalheiras presented greater predominance of PT and PP, while Cruzeta had the highest values of FRS. Chl-a and SS values were also consistent with phosphorus values: Chl-a was higher in Gargalheiras, while SS, mainly inorganic, were higher in Cruzeta. Gargalheiras presented anoxic conditions close to the sediment from May 2015 to December 2015, which may induce the release of phosphorus from the sediment to the water column. Values that are too high during the shallower months, especially in Cruzeta, may have been influenced by the release of P from sediment through wind resuspension. Conclusions The amounts and predominant types of phosphorus in the water column are of great importance to understand the phosphorus dynamics and will support restoration plans for the studied environments. In this study it was possible to verify that the reservoirs are susceptible to the release of P from the sediment due to the environmental conditions, mainly low depths, resuspension of the wind and anoxia in the hypolimnion.

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Phytoplankton responses to an extreme drought season: A case study at two reservoirs from a semiarid region, Northeastern Brazil

Journal of Limnology ◽

10.4081/jlimnol.2019.1869 ◽

2019 ◽

Vol 78 (2) ◽

Cited By ~ 1

Author(s):

Carlos Y. B. Oliveira ◽

Cicero D. L. Oliveira ◽

Ayanne J. G. Almeida ◽

Alfredo O. Gálvez ◽

Danielli M. Dantas

Keyword(s):

Electrical Conductivity ◽

Phytoplankton Biomass ◽

Inorganic Nitrogen ◽

Abiotic Factors ◽

Soluble Reactive Phosphorus ◽

Extreme Drought ◽

Northeastern Brazil ◽

Semiarid Region ◽

Drought Period ◽

Reactive Phosphorus

The temporal phytoplankton biomass variation at two Neotropical reservoirs during an extreme drought season were analyzed. Here we sought to evaluate the main abiotic factors involved in dynamics of phytoplankton during this drought period. The main difference between the reservoirs was the intensive fish and shrimp farming in one of the reservoirs. For quantitative analysis, sampling with bottles were carried out at an average depth of 0.5m. Water temperature, pH and electrical conductivity parameters were measured in situ and water samples were collected for dissolved inorganic nitrogen and soluble reactive phosphorus analyses. Aquaculture was probably one among the causes for the reservoirs were so different in the physical and chemical variables, as shown by the principal components analysis. The results showed specific groups dominance in both reservoirs. In the Cachoeira II reservoir, an invasive dinoflagellate, Ceratium furcoides, was present in all analyzed months, while, in the Saco I reservoir, cyanobacteria group represented more than 50% of phytoplankton biomass, mainly Microcystis aeruginosa and Dolichospermum sp. In two reservoirs precipitation, soluble reactive phosphorus and electrical conductivity were positively related with phytoplankton. Phytoplankton biomass was considerably larger in the Cachoeira II reservoir, due to the greater size and biovolume of the dominant dinoflagellate. These findings suggest that species dominance in extreme drought events may be favored.

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Spatial–Temporal Distribution of Phosphorus Fractions and Their Relationship in Water–Sediment Phases in the Tuojiang River, China

Water ◽

10.3390/w14010027 ◽

2021 ◽

Vol 14 (1) ◽

pp. 27

Author(s):

Dandan Liu ◽

Xueying Li ◽

Yue Zhang ◽

Zhibo Lu ◽

Lu Bai ◽

...

Keyword(s):

Organic Phosphorus ◽

Anthropogenic Activities ◽

Soluble Reactive Phosphorus ◽

Temporal Distribution ◽

Principal Component ◽

Phosphorus Fractions ◽

Primary Data ◽

Particulate Phosphorus ◽

Overlying Water ◽

Water And Sediment

Understanding the distribution and transportation of phosphorus is vital for the sustainable development of aquatic environmental protection and ecological security. The spatial–temporal distribution of phosphorus fractions in water–sediment phases in river systems and their relationships remain unclear in Southwest China. In this study, the spatial and temporal distribution of phosphorus fractions in water–sediment phases in the Tuojiang River, a primary tributary of the Yangtze River which plays important roles in the economy and ecology of the region, and the relationships among the different phosphorus fractions were analyzed. These fractions were soluble reactive phosphorus (SRP), dissolved organic phosphorus (DOP), and total particulate phosphorus (PP) fractions in water, and exchangeable phosphorus (Ex-P), organic phosphorus (Or-P), phosphorus bound by Fe oxides (Fe-P), authigenic phosphorus (Ca-P), detrital phosphorus (De-P), and refractory phosphorus (Res-P) fractions in sediment. The SPR and Fe-P were the dominant phosphorus fractions in the water and sediment, respectively. The TP content was greater in the lower reaches than in the middle and upper reaches. The average abundances of most phosphorus fractions in water–sediment phases showed significant seasonal variations. The Fe-P, Org-P, and TP in sediments were released to the water interface, resulting in the increase of phosphorus in the overlying water. Redundancy analysis (RDA) indicated that the physicochemical properties of water and sediment have a certain influence on the spatial–temporal distribution of the phosphorus fractions. Principal component analysis (PCA) revealed that the main phosphorus source was anthropogenic activities. These results provide primary data regarding phosphorus fractions and contribute to understanding phosphorus cycling and controlling phosphorus pollution in the Tuojiang River.

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The Integrated Catchments model of Phosphorus dynamics (INCA-P), a new approach for multiple source assessment in heterogeneous river systems: model structure and equations

Hydrology and Earth System Sciences ◽

10.5194/hess-6-583-2002 ◽

2002 ◽

Vol 6 (3) ◽

pp. 583-606 ◽

Cited By ~ 109

Author(s):

A. J. Wade ◽

P. G. Whitehead ◽

D. Butterfield

Keyword(s):

Water Quality ◽

Total Phosphorus ◽

Management Practices ◽

Soluble Reactive Phosphorus ◽

Particulate Phosphorus ◽

Model Structure ◽

River Systems ◽

Soil System ◽

Phosphorus Dynamics ◽

Reactive Phosphorus

Abstract. A new model has been developed for assessing the effects of multiple sources of phosphorus on the water quality and aquatic ecology in heterogeneous river systems. The Integrated Catchments model for Phosphorus (INCA-P) is a process-based, mass balance model that simulates the phosphorus dynamics in both the plant/soil system and the stream. The model simulates the spatial variations in phosphorus export from different land use types within a river system using a semi-distributed representation, thereby accounting for the impacts of different land management practices, such as organic and inorganic fertiliser and wastewater applications. The land phase of INCA-P includes a simplified representation of direct runoff, soilwater and groundwater flows, and the soil processes that involve phosphorus. In addition, the model includes a multi-reach in-stream component that routes water down the main river channel. It simulates Organic and Inorganic Phosphorus concentrations in the land phase, and Total Phosphorus (dissolved plus particulate phosphorus) concentrations in the in-stream phase. In-stream Soluble Reactive Phosphorus concentrations are determined from the Total Phosphorus concentrations and the macrophyte, epiphyte and algal biomasses are simulated also. This paper describes the model structure and equations, the limitations and the potential utility of the approach. Keywords: modelling, water quality, phosphorus, soluble reactive phosphorus, basin management

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Spatial and Temporal Distribution of Particulate Phosphorus and Their Correlation with Environmental Factors in a Shallow Eutrophic Chinese Lake (Lake Taihu)

International Journal of Environmental Research and Public Health ◽

10.3390/ijerph15112355 ◽

2018 ◽

Vol 15 (11) ◽

pp. 2355 ◽

Cited By ~ 5

Author(s):

Ming Kong ◽

Jianying Chao ◽

Wei Zhuang ◽

Peifang Wang ◽

Chao Wang ◽

...

Keyword(s):

Particulate Matter ◽

Lake Water ◽

Organic Phosphorus ◽

Lake Taihu ◽

Large Fraction ◽

Soluble Reactive Phosphorus ◽

Particulate Phosphorus ◽

Dominant Form ◽

Important Indicator ◽

Chinese Lake

Spatial and seasonal variations of particulate phosphorus (PP) in a large shallow, eutrophic Lake Taihu with different ecotypes (including a phytoplankton-dominated zone, lake center zone, estuary zone and macrophyte-dominated zone) were investigated. The results showed that particulate organic phosphorus (POP) was the dominant form of PP (>88.0%). The concentration of POP showed higher levels in the bloom-sensitive northwestern zone (phytoplankton-dominated zone and estuary zone) during warm seasons, phytoplankton blooms and input of exogenous particulate matter were the main sources of POP in the lake water. Based on 31P nuclear magnetic resonance (31P NMR) analysis, orthophosphate (Ortho-P) was the dominant molecular species of PP and positively correlated with soluble reactive phosphorus (SRP) (p < 0.01). This suggested that the release of Ortho-P from suspended particulate matter (SPM) was the main source of SRP in the lake water. Pyrophosphate (Pyro-P), which is regarded as a highly labile species of P compounds, represented a large fraction of PP, and its significant positive correlations with chlorophyll a (Chl a), indicated that the concentration of Pyro-P could be used as an important indicator for the degree of eutrophication of Lake Taihu. These results proved that PP in lake water was a significant factor supporting lake eutrophication and must be controlled.

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Spatial Variations in the Abundance and Chemical Speciation of Phosphorus across the River–Sea Interface in the Northern Beibu Gulf

Water ◽

10.3390/w10081103 ◽

2018 ◽

Vol 10 (8) ◽

pp. 1103 ◽

Cited By ~ 3

Author(s):

Bin Yang ◽

Zhen-Jun Kang ◽

Dong-Liang Lu ◽

Solomon Dan ◽

Zhi-Ming Ning ◽

...

Keyword(s):

Total Phosphorus ◽

Coastal Waters ◽

Organic Phosphorus ◽

Inorganic Nitrogen ◽

Inorganic Phosphorus ◽

Particulate Phosphorus ◽

Beibu Gulf ◽

Phosphorus Species ◽

Dissolved Phosphorus ◽

Dissolved Inorganic Phosphorus

Water samples were collected to measure dissolved and particulate phosphorus species in order to examine the dynamics of phosphorus in the water column across the river–sea interface from the lower Dafengjiang River to the open Beibu Gulf. Dissolved inorganic phosphorus concentrations were as high as 0.90 ± 0.42 μM in river water but decreased dramatically to as low as 0.02 ± 0.01 μM in open coastal waters. Total dissolved phosphorus was largely measured in the form of dissolved inorganic phosphorus in river waters (58% ± 18%), whereas dissolved organic phosphorus became the predominant species (>90% on average) in open coastal waters. Total dissolved phosphorus was the dominant species, comprising 76% ± 16% of the total phosphorus, while total particulate phosphorus only comprised 24% ± 16% of the total phosphorus pool. Riverine inputs, physical and biological processes, and particulate phosphorus regeneration were the dominant factors responsible for the dynamic variations of phosphorus species in the study area. Based on a two-end-member mixing model, the biological uptake resulted in a dissolved inorganic phosphorus depletion of 0.12 ± 0.08 μM in the coastal surface water, whereas the replenishment of dissolved inorganic phosphorus in the lower river from particle P regeneration and release resulted in an increase (0.19 ± 0.22 μM) of dissolved inorganic phosphorus in the estuarine mixing region. The molar ratios of dissolved inorganic nitrogen to dissolved inorganic phosphorus and dissolved silicate to dissolved inorganic phosphorus in the open surface waters were >22, suggesting that, although the lower Dafengjiang River contained elevated concentrations of dissolved inorganic phosphorus, the northern Beibu Gulf was an overall P-limited coastal ecosystem.

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The Relationship of Lake Morphometry and Phosphorus Dynamics of a Tropical Highland Lake: Lake Tana, Ethiopia

Water ◽

10.3390/w12082243 ◽

2020 ◽

Vol 12 (8) ◽

pp. 2243 ◽

Cited By ~ 1

Author(s):

Mebrahtom G. Kebedew ◽

Aron A. Kibret ◽

Seifu A. Tilahun ◽

Mulugeta A. Belete ◽

Fasikaw A. Zimale ◽

...

Keyword(s):

Water Quality ◽

Water Resources ◽

Water Column ◽

Available Phosphorus ◽

Lake Morphometry ◽

Lake Tana ◽

Dissolved Phosphorus ◽

Phosphorus Dynamics ◽

Water Hyacinths ◽

The Relationship

Lakes hold most of the world’s fresh surface water resources. Safeguarding these resources from water quality degradation requires knowledge of the relationship between lake morphometry and water quality. The 3046-km2 Lake Tana in Ethiopia is one of the water resources in which the water quality is decreasing and water hyacinths have invaded. The objective of this study is to understand the interaction between the lake morphometry and water quality and specifically the phosphorus dynamics and their effect on the water hyacinths. A bathymetric survey was conducted in late 2017. Various morphometric parameters were derived, and both these parameters and sediment available phosphorus were regressed with the dissolved phosphorus. The results show that, with a wave base depth that is nearly equal to a maximum depth of 14.8 m, the bottom sediments were continuously suspended in the water column. As a result of the resuspension mixing, we found that the dissolved phosphorus in the water column decreased with lake depth and increased with sediment available phosphorus (R2 = 0.84) in the northern half of the lake. This relationship is not as strong in the south due to a large flow of Gilgel Abay to the outlets. Water hyacinths were found where the lake was shallow and the available phosphorus was elevated. The large reservoir of sediment phosphorus will hamper any remedial efforts in removing the water hyacinths.

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Effects of Lanthanum Modified Bentonite and Polyaluminium Chloride on the Environmental Variables in the Water and Sediment Phosphorus Form in Lake Yanglan, China

Water ◽

10.3390/w13141947 ◽

2021 ◽

Vol 13 (14) ◽

pp. 1947

Author(s):

Ling Su ◽

Chen Zhong ◽

Lei Gan ◽

Xiaolin He ◽

Jinlei Yu ◽

...

Keyword(s):

Suspended Solids ◽

Soluble Reactive Phosphorus ◽

Particulate Phosphorus ◽

Modified Bentonite ◽

Combined Application ◽

Water And Sediment ◽

Phosphorus Form ◽

Labile P ◽

Reactive Phosphorus ◽

Polyaluminium Chloride

The application of lanthanum modified bentonite (Phoslock®) and polyaluminium chloride (PAC) is popular in the restoration of European temperate lakes; however, the effects of the application on the concentrations of phosphorus (P) in both the water and the sediments have been poorly evaluated to date. We studied the effects of the application of Phoslock® + PAC on the concentrations of total phosphorus (TP), particulate phosphorus (PP), soluble reactive phosphorus (SRP), total suspended solids (TSS) and chlorophyll a (Chla) in the water, and different P forms in the sediments, in an isolated part of Lake Yanglan. The results showed that the concentrations of TP, PP, SRP, TSS and Chla decreased significantly after the addition of Phoslock® + PAC. Moreover, the concentrations of labile-P, reductant-soluble-P and organic-P in the sediments were also significantly decreased after the Phoslock® + PAC application. However, the concentrations of both the stable apatite-P and residual-P in the sediments after application of Phoslock® + PAC were much higher than the pre-addition values, while the concentrations of metal-oxide-P did not differ significantly between the pre- and post- application conditions. Our findings imply that the combined application of Phoslock® and PAC can be used in the restoration of subtropical shallow lakes, to reduce the concentrations of P in the water and suppress the release of P from the sediments.

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Seasonal Variations of Phosphorus Species in the Overlying and Pore Waters of the Tuohe River, China

Journal of Chemistry ◽

10.1155/2019/6727239 ◽

2019 ◽

Vol 2019 ◽

pp. 1-9

Author(s):

Qing Xu ◽

Xiaoping Yu ◽

Yafei Guo ◽

Tianlong Deng ◽

Yu-Wei Chen ◽

...

Keyword(s):

Seasonal Variations ◽

Yangtze River ◽

Algal Bloom ◽

Soluble Reactive Phosphorus ◽

Pore Waters ◽

Phosphorus Species ◽

Dissolved Phosphorus ◽

Vertical Distributions ◽

Reactive Phosphorus ◽

Main Factor

Overlying sediment and pore waters were collected in summer and winter at upstream (Jintang) and downstream (Neijiang) sites of the Tuohe River, which is one of the five largest tributaries of the Yangtze River in China. Phosphorus species, including soluble reactive phosphorus (SRP), soluble unreactive phosphorus (SUP), and total dissolved phosphorus (TDP), and some diagenetic constituents including dissolved Fe(II), Mn(II), and sulfide in overlying and pore waters, were measured systematically. The seasonal variations and vertical distributions of phosphorus species in overlying and pore waters at both sampling sites were obtained to elucidate some aspects of the transport and transformations of phosphorus. Based on the profiles of pore and overlying waters as well as the TDN/TDP data during an algal bloom in 2007, it was clearly demonstrated that phosphorus was the main factor limiting the phytoplankton growth in the Tuohe River.

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Particle export fluxes to the oxygen minimum zone of the eastern tropical North Atlantic

Biogeosciences ◽

10.5194/bg-14-1825-2017 ◽

2017 ◽

Vol 14 (7) ◽

pp. 1825-1838 ◽

Cited By ~ 12

Author(s):

Anja Engel ◽

Hannes Wagner ◽

Frédéric A. C. Le Moigne ◽

Samuel T. Wilson

Keyword(s):

Organic Matter ◽

North Atlantic ◽

Organic Phosphorus ◽

Euphotic Zone ◽

Carbon Export ◽

Organic Matter Quality ◽

B Values ◽

Chl A ◽

Tropical North Atlantic ◽

Particle Export

Abstract. In the ocean, sinking of particulate organic matter (POM) drives carbon export from the euphotic zone and supplies nutrition to mesopelagic communities, the feeding and degradation activities of which in turn lead to export flux attenuation. Oxygen (O2) minimum zones (OMZs) with suboxic water layers (< 5 µmol O2 kg−1) show a lower carbon flux attenuation compared to well-oxygenated waters (> 100 µmol O2 kg−1), supposedly due to reduced heterotrophic activity. This study focuses on sinking particle fluxes through hypoxic mesopelagic waters (< 60 µmol O2 kg−1); these represent ∼  100 times more ocean volume globally compared to suboxic waters, but they have less been studied. Particle export fluxes and attenuation coefficients were determined in the eastern tropical North Atlantic (ETNA) using two surface-tethered drifting sediment trap arrays with seven trapping depths located between 100 and 600 m. Data on particulate matter fluxes were fitted to the normalized power function Fz =  F100 (z∕100)−b, with F100 being the flux at a depth (z) of 100 m and b being the attenuation coefficient. Higher b values suggest stronger flux attenuation and are influenced by factors such as faster degradation at higher temperatures. In this study, b values of organic carbon fluxes varied between 0.74 and 0.80 and were in the intermediate range of previous reports, but lower than expected from seawater temperatures within the upper 500 m. During this study, highest b values were determined for fluxes of particulate hydrolyzable amino acids (PHAA), followed by particulate organic phosphorus (POP), nitrogen (PN), carbon (POC), chlorophyll a (Chl a) and transparent exopolymer particles (TEP), pointing to a sequential degradation of organic matter components during sinking. Our study suggests that in addition to O2 concentration, organic matter composition co-determines transfer efficiency through the mesopelagic. The magnitude of future carbon export fluxes may therefore also depend on how organic matter quality in the surface ocean changes under influence of warming, acidification and enhanced stratification.

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Movements of Phosphorus Between its Biologically Important Forms in Lake Water

Journal of the Fisheries Research Board of Canada ◽

10.1139/f73-242 ◽

1973 ◽

Vol 30 (10) ◽

pp. 1525-1536 ◽

Cited By ~ 106

Author(s):

D. R. S. Lean

Keyword(s):

Molecular Weight ◽

Lake Water ◽

Membrane Filtration ◽

Organic Phosphorus ◽

Gel Filtration ◽

Particulate Fraction ◽

Low Molecular Weight ◽

Radioactive Phosphorus ◽

Dissolved Phosphorus ◽

Kinetics Of

A model consistent with the kinetics of phosphorus in epilimnetic lake water was developed. Adding 32PO4 to lake water and separating the major forms of dissolved phosphorus by Sephadex gel filtration showed that the exchange mechanism between inorganic phosphate and the particulate fraction predominates. At the same time, a low-molecular-weight phosphorus compound is excreted which combines with colloids in lake water, releasing phosphate from the colloid and making the phosphate available for "transfer" again. This rapid cycling of phosphorus between the four principal forms — the particulate fraction, the low-molecular-weight P compound, colloidal P, and phosphate — appears to contribute to formation of colloids in lake water. No direct complexing of phosphate to the colloid was observed. Only in the presence of algae, bacteria, and other particulate matter did the radioactive phosphorus move to the low-molecular weight and the colloidal forms. The low-molecular-weight compound is negatively charged, as is the colloidal P, but to a lesser degree. Both are removed by anion exchange materials along with phosphate, but the rate that they move into the fraction removed by membrane filtration is different from that for phosphate. When filtrate is refiltered a large amount of the colloidal P is retained by the filter. This complicates measurements of transfer and makes previous studies on utilization of dissolved organic phosphorus of doubtful value since corrections for filter retention were rarely, if ever, made.

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