Uncertainty assessment of a dominant-process catchment model of dissolved phosphorus transfer

Abstract. We developed a parsimonious topography-based hydrologic model coupled with a soil biogeochemistry sub-model in order to improve understanding and prediction of soluble reactive phosphorus (SRP) transfer in agricultural headwater catchments. The model structure aims to capture the dominant hydrological and biogeochemical processes identified from multiscale observations in a research catchment (Kervidy–Naizin, 5 km2). Groundwater fluctuations, responsible for the connection of soil SRP production zones to the stream, were simulated with a fully distributed hydrologic model at 20 m resolution. The spatial variability of the soil phosphorus content and the temporal variability of soil moisture and temperature, which had previously been identified as key controlling factors of SRP solubilization in soils, were included as part of an empirical soil biogeochemistry sub-model. The modelling approach included an analysis of the information contained in the calibration data and propagation of uncertainty in model predictions using a generalized likelihood uncertainty estimation (GLUE) "limits of acceptability" framework. Overall, the model appeared to perform well given the uncertainty in the observational data, with a Nash–Sutcliffe efficiency on daily SRP loads between 0.1 and 0.8 for acceptable models. The role of hydrological connectivity via groundwater fluctuation and the role of increased SRP solubilization following dry/hot periods were captured well. We conclude that in the absence of near-continuous monitoring, the amount of information contained in the data is limited; hence, parsimonious models are more relevant than highly parameterized models. An analysis of uncertainty in the data is recommended for model calibration in order to provide reliable predictions.

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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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Vertical phosphorus migration in biosolids-amended soils : concentrations in soils and leachates.

10.32920/ryerson.14644857.v1 ◽

2021 ◽

Author(s):

Yulia Markunas

Keyword(s):

Vertical Migration ◽

Organic Phosphorus ◽

Soil Phosphorus ◽

Soluble Reactive Phosphorus ◽

Land Application ◽

Soil Leachate ◽

Different Depths ◽

Receiving Waters ◽

Reactive Phosphorus ◽

Biosolids Application

The impacts of biosolids land application on soil phosphorus and subsequent transfer to aquatic ecosystems in the condition of the minimal slope were assessed. Soil, representing typical "Non response" Ontario soil, was amended with anaerobically digested biosolids at a rate of 8 tonnes/ha. Over five months, soil samples from two different depths were sequentially fractionated to determine various inorganic and organic phosphorus pools in order to evaluate phosphorus vertical migration within a soil profile. Soil leachate was analyzed for soluble reactive phosphorus and added to the aquariums mimicking receiving surface waters. Water from aquariums was tested for the presence of eutrophication. The results indicated that biosolids application did not significantly affect phosphorus concentrations in soil and did not cause phosphorus vertical migration. The concentrations of soluble reactive phosphorus also were not affected by biosolids. No signs of eutrophication were observed in receiving waters.

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Vertical phosphorus migration in a biosolids-amended sandy loam soil in laboratory settings: concentrations in soils and leachates

10.32920/14638197 ◽

2021 ◽

Author(s):

Yulia Markunas ◽

Vadim Bostan ◽

Andrew Laursen ◽

Michael Payne ◽

Lynda McCarthy

Keyword(s):

Vertical Migration ◽

Sandy Loam ◽

Organic Phosphorus ◽

Soil Phosphorus ◽

Soluble Reactive Phosphorus ◽

Dry Weight ◽

Land Application ◽

Soil Leachate ◽

Laboratory Setup ◽

Reactive Phosphorus

The impacts of biosolids land application on soil phosphorus and subsequent vertical migration to tile drainage were assessed in a laboratory setup. Soil, representing typical “nonresponse” Ontario soil as specified by Ontario Ministry of Agriculture, Food, and Rural Affairs (OMAFRA), was amended with anaerobically digested biosolids at a rate of 8Mgha−1 (dry weight). Over five months, these amended soil samples from two different depths were sequentially fractionated to determine various inorganic and organic phosphorus pools in order to evaluate phosphorus vertical migration within a soil profile. Soil leachate was analyzed for soluble reactive phosphorus.The results indicated that biosolids application did not significantly affect phosphorus concentrations in soil and did not cause phosphorus vertical migration. The concentrations of soluble reactive phosphorus also were not significantly affected by biosolids.

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Vertical Phosphorus Migration in a Biosolids-Amended Sandy Loam Soil in Laboratory Settings: Concentrations in Soils and Leachates

Applied and Environmental Soil Science ◽

10.1155/2016/3460939 ◽

2016 ◽

Vol 2016 ◽

pp. 1-8

Author(s):

Yulia Markunas ◽

Vadim Bostan ◽

Andrew Laursen ◽

Michael Payne ◽

Lynda McCarthy

Keyword(s):

Vertical Migration ◽

Sandy Loam ◽

Organic Phosphorus ◽

Soil Phosphorus ◽

Soluble Reactive Phosphorus ◽

Dry Weight ◽

Land Application ◽

Soil Leachate ◽

Laboratory Setup ◽

Reactive Phosphorus

The impacts of biosolids land application on soil phosphorus and subsequent vertical migration to tile drainage were assessed in a laboratory setup. Soil, representing typical “nonresponse” Ontario soil as specified by Ontario Ministry of Agriculture, Food, and Rural Affairs (OMAFRA), was amended with anaerobically digested biosolids at a rate of 8 Mg ha−1 (dry weight). Over five months, these amended soil samples from two different depths were sequentially fractionated to determine various inorganic and organic phosphorus pools in order to evaluate phosphorus vertical migration within a soil profile. Soil leachate was analyzed for soluble reactive phosphorus. The results indicated that biosolids application did not significantly affect phosphorus concentrations in soil and did not cause phosphorus vertical migration. The concentrations of soluble reactive phosphorus also were not significantly affected by biosolids.

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Vertical phosphorus migration in biosolids-amended soils : concentrations in soils and leachates.

10.32920/ryerson.14644857 ◽

2021 ◽

Author(s):

Yulia Markunas

Keyword(s):

Vertical Migration ◽

Organic Phosphorus ◽

Soil Phosphorus ◽

Soluble Reactive Phosphorus ◽

Land Application ◽

Soil Leachate ◽

Different Depths ◽

Receiving Waters ◽

Reactive Phosphorus ◽

Biosolids Application

The impacts of biosolids land application on soil phosphorus and subsequent transfer to aquatic ecosystems in the condition of the minimal slope were assessed. Soil, representing typical "Non response" Ontario soil, was amended with anaerobically digested biosolids at a rate of 8 tonnes/ha. Over five months, soil samples from two different depths were sequentially fractionated to determine various inorganic and organic phosphorus pools in order to evaluate phosphorus vertical migration within a soil profile. Soil leachate was analyzed for soluble reactive phosphorus and added to the aquariums mimicking receiving surface waters. Water from aquariums was tested for the presence of eutrophication. The results indicated that biosolids application did not significantly affect phosphorus concentrations in soil and did not cause phosphorus vertical migration. The concentrations of soluble reactive phosphorus also were not affected by biosolids. No signs of eutrophication were observed in receiving waters.

Download Full-text

Vertical phosphorus migration in a biosolids-amended sandy loam soil in laboratory settings: concentrations in soils and leachates

10.32920/14638197.v1 ◽

2021 ◽

Author(s):

Yulia Markunas ◽

Vadim Bostan ◽

Andrew Laursen ◽

Michael Payne ◽

Lynda McCarthy

Keyword(s):

Vertical Migration ◽

Sandy Loam ◽

Organic Phosphorus ◽

Soil Phosphorus ◽

Soluble Reactive Phosphorus ◽

Dry Weight ◽

Land Application ◽

Soil Leachate ◽

Laboratory Setup ◽

Reactive Phosphorus

The impacts of biosolids land application on soil phosphorus and subsequent vertical migration to tile drainage were assessed in a laboratory setup. Soil, representing typical “nonresponse” Ontario soil as specified by Ontario Ministry of Agriculture, Food, and Rural Affairs (OMAFRA), was amended with anaerobically digested biosolids at a rate of 8Mgha−1 (dry weight). Over five months, these amended soil samples from two different depths were sequentially fractionated to determine various inorganic and organic phosphorus pools in order to evaluate phosphorus vertical migration within a soil profile. Soil leachate was analyzed for soluble reactive phosphorus.The results indicated that biosolids application did not significantly affect phosphorus concentrations in soil and did not cause phosphorus vertical migration. The concentrations of soluble reactive phosphorus also were not significantly affected by biosolids.

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Trends in dissolved phosphorus in Gray Luvisol soil profiles after forest harvest

Canadian Journal of Soil Science ◽

10.4141/s04-030 ◽

2005 ◽

Vol 85 (1) ◽

pp. 89-101 ◽

Cited By ~ 7

Author(s):

I. R. Whitson ◽

S. Abboud ◽

E. E. Prepas ◽

D. S. Chanasyk

Keyword(s):

Forest Floor ◽

Soil Phosphorus ◽

Soluble Reactive Phosphorus ◽

Water Soluble ◽

Phosphorus Concentration ◽

Negative Consequences ◽

Forest Harvest ◽

Dissolved Phosphorus ◽

P Concentration ◽

Gray Luvisol

Forest disturbances that increase P export from hillslopes will have negative consequences for site productivity and regional water quality. We studied P behavior in Gray Luvisols to understand the soil profile’s influence on P export from typical hillslopes of the Boreal Plain ecozone. We hypothesized that (1) P concentration is highest in upper horizons, (2) solution P is primarily in the dissolved and organic form, and (3) forest harvest will increase solution P concentration. We analyzed the soil solution, with emphasis on P, and determined P sorption properties of key soil horizons. Mean soluble reactive phosphorus concentration decreased with depth, ranging from 64 mg L-1 in the forest floor to 0.01 mg L-1 in the groundwater zone; solution P was mostly orthophosphate. Water soluble phosphorus decreased from 74 ± 9 to 41 ± 9 mg L-1 and extractable phosphorus was reduced in the forest floor only on two of four sampling occasions after harvest. Dissolved organic carbon may indirectly promote orthophosphate dominance in solution by complexing metal cations that would otherwise precipitate metal-P from solution. Gray Luvisols probably export P to soils lower on the hillslope catena, such as those of the Gleysolic and Organic Orders, both commonly associated with wetlands. Key words: Forest soil, phosphorus, orthophosphate, Gray Luvisol, biogeochemistry, sorption

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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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