Filterable organic phosphorus

Clark etal. (1999) Marine water, filterable organic phosphorus Solid Pacific Ocean... 

We noted earlier that mass spectrometry had not been used to any extent in speciation studies of organic phosphorus in natural environments. Here we define phosphorus speciation as the determination of actual molecular formulas and structures of molecules containing phosphorus, and not the more commonly accepted, broad classes of phosphorus such as filterable reactive phosphorus, total filterable phosphorus, filterable organic phosphorus, etc. While a few studies have focused on particular classes of organic phosphorus, such as the inositol phosphates, we are not aware of any attempt to broadly speciate... 

Filterable organic phosphorus isolated from several sites in and adjacent to the ENR were analysed by this method, using off-line phosphorus-specific mass spectrometry detection. The organic phosphorus was isolated and concentrated by tangential ultrafiltration and lyophilization to produce concentration factors of —25 and final total organic phosphorus concentrations of —1 mg P/1. Column effluent was collected in 1 ml fractions after ultraviolet detection at 214 nm. The chromatographic fractions, along with a matrix blank and 1 and 10 mg/1... 

Figure 3.19 contains phosphograms of filterable organic phosphorus isolated from the outlet of the ENR and from within Water Conservation Area 2A. Clearly, the filterable organic phosphorus from the ENR, which is presumably formed within the wetland and is younger , is different from that in Water Conservation Area 2A. In the next section we describe additional mass spectrometry experiments that attempt to qualitatively identify these different organic phosphorus compounds. 

Dissolved organic matter concentration and isolation of filterable organic phosphorus from surface waters at four sites in the ENR were carried out and the resulting concentrates analysed by ultrahigh-resolution FT-ICR with electrospray ionization. These sites represent a gradation in water residence time within the wetland and include the inflow, the conveyance linking Cells 1 and 3, the output from Cell 4, and the integrated ENR outflow (see Fig. 3.9 for reference). Detailed mass analysis of each peak in these spectra allowed several... 

Differences in the intensity of management clearly influence the relative concentrations and importance of organic phosphorus, which is reflected in stream and river water. As an example, Christmas and Whitton (1998) reported that filterable organic phosphorus concentrations in the... 

Speciation of filterable organic phosphorus compounds in drainage water... 

Florida rivers of contrasting trophic status (Paul et al., 1991), while a variety of filterable organic phosphorus compounds were detected in water from a treatment wetland by capillary-electrophoresis separation and detection by mass-spectrometry (Llewelyn et al., 2002 Cooper et al.. Chapter 3, this volume). Similarly, enzymatic hydrolysis techniques have yielded information on functional organic phosphorus classes in natural waters (e.g. Herbes et a/., 1975 Shan et al., 1994). However, it is difficult to infer terrestrial origins for organic phosphorus compounds measured in aquatic environments, because they are equally likely to be derived from autochthonous sources such as algal or bacterial cells. 

During the last decade, information on the organic phosphorus composition of soil solutions and water extracts has been obtained by phosphatase hydrolysis. This technique not only gives structural information on filterable organic phosphorus, but also indicates its potential biological availability. In solution from Scottish upland soils, up to 64% of the filterable organic phosphorus was hydrolysed by non-specific phosphatases (Shand and Smith, 1997), while hydrolysable unreactive phosphorus in water extracts of Australian pasture soils was dominated by phosphate diesters and myo-inositol hexakisphosphate (Turner et al., 2002a). Only small concentrations of labile monoesters were detected in the latter study, possibly due to the rapid hydrolysis of labile compounds by soil phosphatase enzymes. 

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