Concentrations and Kinetics of Phosphorus Fractions in Water from Streams Entering Lake Memphremagog

1978 ◽  
Vol 35 (3) ◽  
pp. 315-328 ◽  
Author(s):  
Robert Henry Peters
Keyword(s):  
Molecular Weight ◽  
River Water ◽  
Weight Fraction ◽  
Water Soluble ◽  
Organic P ◽  
P Fractions ◽  
P Concentration ◽  
Large Molecular Weight ◽  
Soluble P ◽  
Total P

This study examines the possibility that the proportions of different P fractions may vary among rivers, and hence, that the P supplied to lakes may differ in its availability for algae regardless of any similarities in the total P concentration of river waters. Surface water from eight streams and groundwater was collected at roughly monthly intervals from June 1975 to September 1976 and analyzed to determine the concentrations of P fractions and the interrelations between these forms and orthophosphate. Despite differences in total P concentration, (18–64 μg/L) the proportions of P in different fractions were relatively constant seasonally and geographically. Soluble P formed about one third and PO4 < 10% of the total P. These values were not greatly affected by urban drainage but both were increased in small headwater streams during periods of low water. Soluble P was divided into two roughly equal fractions by gel filtration: a large molecular weight fraction (> 5000 mol wt) which eluted at void volume and a small molecular weight fraction (< 400 mol wt) which eluted with 32P-PO4. This latter fraction also included some small organic phosphates. Soluble reactive phosphate consistently overestimated PO4. The exchange of P between PO4 and suspended material was slow in winter and more rapid in summer, although only rivers draining lakes, embayments, or bogs reached the very rapid values reported from lakes. As in lakes, soluble organic P entered into the short-term P dynamics of streams as indicated by the labeling of large molecular weight P during equilibration of river water with radioactive phosphate. This exchange shows that at least a portion of the soluble organic and particulate P is available to the plankton once the river water enters a lake. The uncertainty as to the size of this portion leads to uncertainty in predicting the impact of P loading on lakes. Key words: nutrient budget, P loading, orthophosphate, soluble organic P, drainage basins

Concentrations and Kinetics of Phosphorus Fractions Along the Trophic Gradient of Lake Memphremagog

1979 ◽  
Vol 36 (8) ◽  
pp. 970-979 ◽  
Author(s):  
Robert Henry Peters
Keyword(s):  
Molecular Weight ◽  
Total Phosphorus ◽  
Gel Filtration ◽  
Soluble Reactive Phosphorus ◽  
Small Molecular Weight ◽  
P Deficiency ◽  
Large Molecular Weight ◽  
Soluble P ◽  
Phosphorus Production ◽  
Total P

Published relationships between chlorophyll and total phosphorus concentrations show that the amount of chlorophyll developed per unit of total P increases as total P increases. If the availability of phosphorus changes with lake trophy, this should be reflected in the proportion of total P found in different analytical fractions. From June 1975 to September 1976, the concentrations of total phosphorus, soluble phosphorus, orthophosphate, large molecular weight phosphorus (> 5000 mol wt) and small molecular weight phosphorus (< 400 mol wt) were measured at six sites along the phosphorus-production gradient of Lake Memphremagog; 32P-PO4 was used to follow short-term exchanges between available orthophosphate and other fractions. Total P declined threefold among sites but the proportion of different fractions remained relatively constant which suggests that any disproportionate loss from one compartment is made good by exchanges with the others. On average, soluble P formed\of total P, soluble reactive phosphorus formed 14%, and PO4 8%; gel filtration showed that ~40% of soluble P was associated with large molecular weight phosphorus and ~40% with small molecular weight phosphorus. Within this basic similarity, was a trend to decreased PO4 concentrations and increased concentrations of soluble P and soluble unreactive phosphorus at more oligotrophic sites. Tracer experiments showed that all fractions exchanged some P with 32P-PO4, although soluble fractions, especially large molecular weight phosphorus, interacted more slowly with orthophosphate than did particulate P. Faster orthophosphate turnover suggested greater P deficiency in more oligotrophic sites. This deficiency may promote the formation of a refractory soluble P which may explain a part of the reduced ratio of chlorophyll to phosphorus when total P is reduced. Key words: orthophosphate, phosphorus, turnover, availability, lakes, gel fitration, soluble organic P

scholarly journals Effects of exogenous phytase supplementation on phosphorus metabolism and digestibility of beef cattle

2017 ◽  
Vol 1 (2) ◽  
pp. 168-178
Author(s):  
C. J. Long ◽  
L. B. Kondratovich ◽  
M. F. Westphalen ◽  
H. H. Stein ◽  
T. L. Felix
Keyword(s):  
Beef Cattle ◽  
Latin Square ◽  
Water Soluble ◽  
Experimental Unit ◽  
Water Soluble P ◽  
P Concentration ◽  
Fecal Output ◽  
P Utilization ◽  
Soluble P ◽  
Total P

Abstract Objectives were to determine interactions between phytase inclusion and dietary P concentration on P utilization by beef cattle fed a starch-based diet. Six ruminally-fistulated steers (BW = 750 ± 61 kg) were allotted to a 6 × 6 Latin square design with a 3 × 2 factorial arrangement of treatments. Factors included phytase inclusion, at 0, 500, or 2,000 phytase units (FTU)/kg of diet DM, and dietary P concentrations, at 0.10% and 0.30% of total diet DM. Feed ingredients, fecal samples, and orts were composited within period, lyophilized and ground. Samples were analyzed for NDF, ADF, CP, fat, ash, total P, and other minerals. Data were analyzed using the MIXED procedure of SAS with animal as the experimental unit. The CORR procedure was used to compare blood and urinary P concentrations. There were no treatment interactions (P ≥ 0.30) for any parameter measured. There were no main effects (P ≥ 0.45) of phytase inclusion on DMI, total fecal output, apparent DM digestibility, water intake, or urinary output. Steers fed 0.10% P had decreased (P &lt; 0.01) DMI and total fecal output, but increased (P &lt; 0.01) apparent DM digestibility compared with steers fed 0.30% P. Although N intake and retention were not affected by treatment, steers fed the 0.10% P diet tended (P = 0.10) to absorb more N compared with steers fed 0.30% P; and, steers fed the 0.10% P diets excreted more N in the urine (P = 0.02) and less N in the feces (P &lt; 0.01) compared with steers fed the 0.30% P diets. Steers fed the 0.10% P diets also consumed 70.1% less (P &lt; 0.01) total P each day, and excreted 51.9% less (P &lt; 0.01) P in feces and 94.6% less P in the urine (P &lt; 0.01) compared with steers fed 0.30% P. Excretion of water-soluble P in the feces was greater (P &lt; 0.01) on a g/d basis for steers fed 0.30% P when compared with steers fed 0.10% P. However, the proportion of total fecal P excreted as water-soluble P increased (P &lt; 0.05) by 23.0% in steers fed 0.10% P compared with steers fed 0.30% P, regardless of phytase inclusion level. There was no effect of dietary phytase concentration on blood or urinary (P ≥ 0.27) P concentrations. Blood P concentration was positively correlated (r = 0.60; P &lt; 0.01) to urinary P concentration when steers were fed 0.10% P; however, when steers were fed 0.30% P, there was no correlation (r = 0.36; P = 0.16) between blood and urine P. Regardless of dietary P concentration, phytase supplementation did not increase calculated P absorption or retention.

scholarly journals Genetic variation of seed phosphorus concentration in winter oilseed rape and development of a NIRS calibration

Euphytica ◽  
2021 ◽  
Vol 217 (4) ◽  
Author(s):  
Jakob Eifler ◽  
Jürgen Enno Wick ◽  
Bernd Steingrobe ◽  
Christian Möllers
Keyword(s):  
Genetic Variation ◽  
Field Experiments ◽  
Seed Quality ◽  
Rapeseed Meal ◽  
Quality Analysis ◽  
Phosphorus Concentration ◽  
Genotypic Differences ◽  
Organic P ◽  
P Concentration ◽  
Total P

AbstractPhytic acid is the major organic phosphorus storage compound in rapeseed. Following oil extraction, the defatted meal is used in feed mixtures for livestock. However, monogastric pigs and chickens can only poorly metabolize phytate. Hence, their excrements are rich in phosphorus (P), which when applied as manure may lead to eutrophication of surface waters. The aim of the present study was to analyze the genetic variation for total and organic P concentration (i.e. mainly phytate) in rapeseed and to compare the results with soybean. Two sets of rapeseed material were tested in field experiments in different environments with varying soil P levels and harvested seeds were used for seed quality analysis. Results revealed significant genotypic differences in total seed P concentration, which ranged from 0.47 to 0.94%. Depending on the experiment, the heritability for total P concentration ranged from 52 to 93%. The organic P portion of total P concentration was above 90% for current rapeseed hybrids. In both sets, there was a significant positive correlation between seed protein and P concentration. A NIRS calibration for total P concentration in intact seeds showed in cross validation a standard error of 0.05% and a coefficient of determination of R2 = 0.83. Total P concentration of soybean seeds and meal was between 0.55 and 0.65%, and around 1.1% for rapeseed meal. Rapeseed meal had a twofold higher ratio of total P to nitrogen concentration as compared to soybean which could be considered adverse when the meal is used for feeding livestock.

STUDY OF PROTEIN FRACTIONS OF HIGH-TEMPERATURE HYDROLYZATES OBTAINED FROM SMOKED SPRAT HEADS

Fisheries ◽  
2020 ◽  
Vol 2020 (2) ◽  
pp. 113-117
Author(s):  
Olga Mezenova ◽  
Vladimir Wolkov ◽  
Larisa Baydalinova ◽  
Natalia Mezenova ◽  
Svetlana Agafonova ◽  
...  
Keyword(s):  
Molecular Weight ◽  
Chemical Composition ◽  
Raw Materials ◽  
Weight Fraction ◽  
Water Soluble ◽  
Protein Fractions ◽  
Raw Material ◽  
Organoleptic Characteristics ◽  
Pre Treatment ◽  
Peptide Fractions

The authors study three fractions obtained as a result of hydrolysis of smoked sprat heads (under temperature of 130oC and presser of 0.25 MPa) – fat, protein water-soluble, and protein-and-mineral ones. Waste from sprat production of two fish canning complexes of the Kaliningrad Region - “RosCon” and “Kolkhoz for the Motherland” - was used as raw material. Hydrolysis was carried out in an aqueous medium in two ways - with preliminary separation of fat and without this operation. The protein fraction was sublimated and its quantitative and qualitative indices were examined - mass yield, solubility, chemical composition and molecular fractional composition of the obtained peptide fractions were determined. The output of sublimated protein fractions is practically independent of the type of raw material and the method of pre-treatment and is 6.47.9% of the mass of raw materials. The chemical composition of protein fractions varies widely in terms of fat (1.4–8.3%), minerals (9.8–13.4%) and proteins (72.1–80.2%). The solubility of the peptide fractions ranged from 91-98%. The molecular weight assessment results showed a high content of a low molecular weight fraction of peptides with an MM of less than 10 kDa in all experimental samples (about 38%). This indicates a high digestibility and biological value of the obtained peptide compositions. Sublimated peptide compositions had typical organoleptic characteristics, pleasant aroma and taste of smoked fish. Ключевые

scholarly journals Effect of Low-Molecular-Weight Fraction of Susabi-nori Water-Soluble Extract on HL-60 Cell Proliferation

2007 ◽  
Vol 54 (5) ◽  
pp. 241-246 ◽  
Author(s):  
Keisuke Tsuge ◽  
Yayoi Watanabe ◽  
Norihide Maeda ◽  
Shin-ichi Abe ◽  
Toru Tsuruhashi ◽  
...  
Keyword(s):  
Molecular Weight ◽  
Cell Proliferation ◽  
Weight Fraction ◽  
Water Soluble ◽  
Low Molecular Weight ◽  
Soluble Extract ◽  
Water Soluble Extract

Phosphate distribution in animal waste slurries

1984 ◽  
Vol 102 (1) ◽  
pp. 159-161 ◽  
Author(s):  
R. G. Gerritse ◽  
R. Vriesema
Keyword(s):  
Molecular Weight ◽  
High Molecular Weight ◽  
Animal Waste ◽  
Organic P ◽  
Veal Calves ◽  
Total P

SummaryResults obtained previously on distribution and behaviour of phosphate between organic and inorganic forms in pig slurries are extended to slurries from wastes of hens, cows and calves. Organic P in the slurries varied from about 1 to 15% of total P, with slurries from veal calves having the lowest content of organic P. In all slurries roughly half of organic P in solution had a high molecular weight (50000 and higher) and is therefore potentially mobile in soils.

A Comparison of Different Phosphorus Fractions as Predictors of Particulate Pigment Levels in Lake Memphremagog and its Tributaries

1982 ◽  
Vol 39 (5) ◽  
pp. 785-790 ◽  
Author(s):  
Robert Henry Peters ◽  
Martin Bergmann
Keyword(s):  
Molecular Weight ◽  
Soluble Reactive Phosphorus ◽  
Particulate Material ◽  
Phosphorus Fractions ◽  
Particulate Phosphorus ◽  
Small Molecular Weight ◽  
Large Molecular Weight ◽  
Reactive Phosphorus ◽  
Lake Waters ◽  
Total P

The amounts of colored particulate material (measured by reflectance) in surface waters of Lake Memphremagog and its tributaries were regressed against concentrations of total phosphorus and several of its component fractions: soluble phosphorus, particulate phosphorus, soluble reactive phosphorus, orthophosphate, large molecular weight phosphorus (> 5000 mol wt) and small molecular weight phosphorus (< 400 mol wt). The correlations were examined to see if one of these fractions was a better predictor of seston concentration, and presumably of other biologically related lake properties, than total P, and to determine if riverine samples differed from lake waters in the relation between concentrations of P and suspended particulates. Total P correlated with colored particulates in both lotic and lentic samples as well as or better than any other fraction. Although river samples showed greater variation than lake samples, the regression lines describing the relations were similar in both lakes and rivers.Key words: phosphorus fractions, lakes, rivers, empirical models, particulate concentration, seston

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