Importance of Terrestrially-Derived, Particulate Phosphorus to Phosphorus Dynamics in a West Coast Estuary

Estuaries ◽  
1995 ◽  
Vol 18 (3) ◽  
pp. 518 ◽  
Author(s):  
R. M. Chambers ◽  
J. W. Fourqurean ◽  
J. T. Hollibaugh ◽  
S. M. Vink
2018 ◽  
Vol 30 (0) ◽  
Author(s):  
Herika Cavalcante ◽  
Fabiana Araújo ◽  
Vanessa Becker

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.


1988 ◽  
Vol 45 (2) ◽  
pp. 210-215 ◽  
Author(s):  
Yves T. Prairie ◽  
Jacob Kalff

We examined the dynamics of particulate phosphorus (PP) in seven headwater streams of southern Quebec draining catchments differing in size, extent of forest cover, and stream channel gradient. The extent of forest cover can be used to predict average [PP]. The magnitude of the temporal fluctuations (variance) in [PP] was strongly related to mean levels. While most streams showed positive relationships between discharge and [PP] in rain events, inverse relations were observed in two streams and possibly the result of the rapid exhaustion of PP. Inverse relationships were also seen in these two streams for samples collected outside rain events. We present a model based on channel gradient and extent of forest cover to predict the slope coefficient of [PP]–discharge relationships and also the occurrence of very rapid exhaustion. We then extend this model to include the influence of precipitation history and catchment size on [PP] in headwater streams. This model accounted for 60% of the variation of the pooled observations from all seven streams and is comparable in predictive power with stream-specific models published elsewhere in the literature.


2002 ◽  
Vol 6 (3) ◽  
pp. 583-606 ◽  
Author(s):  
A. J. Wade ◽  
P. G. Whitehead ◽  
D. Butterfield

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


1959 ◽  
Vol 14 (9) ◽  
pp. 596-597
Author(s):  
Francis H. Palmer
Keyword(s):  

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