CHEMICAL COMPOSITION OF RIVERS AND LAKES 



G51 



seem to contain about 0.1 ppb, but it would not take 

 many like the Danube to raise the world average to 

 Koczy's (1954) estimate of 1 ppb, which seems to be a 

 reasonable figure. 



Table 91. — Uranium content of lakes and rivers 



Locality 



Allegheny River, Pa 



Allegheny River, Pa 



Ohio River, Pa 



Chartiers Creek 



Monongahela River, Pa 



Great Salt Lake, Utah 



Hudson River, N.Y 



St. Lawrence River 



Mississippi River.. 



Various United States rivers: 

 Dissolved 



Total 



Rivers, North America, range.. 



Rivers, world average 



Rivers, central Europe 



Danube at Vienna 



Surface waters, Wisconsin, mi 



nois, and Texas. 

 Lake Mendota, Wis 



Uranium 

 (ppb) 



50 



<25 

 5 



<2.5 

 <25 

 <2. 5 



.022 

 .016 

 .040 



.6 



. 016-. 040 



47 



. 13-3. 5 

 .4 



Author 



Lynch, f?iLowderand Solon (1956). 



Do. 



Do. 



Do. 



Do. 

 Kohman and Saito (1954). 

 Ronaand Urry (1952). 



Do. 



Do. 



Adams, in Holland and Kulp 

 (1954). 



Do. 

 Kohman and Saito (1954). 

 Koczy (1954). 

 Hoflman (1942). 



Do. 



Jndson and Osmond (1955). 

 Do. 



RADIOACTIVE ISOTOPES 



The uranium and radium content of lakes and rivers 

 has been dealt with previously (see p. 45, 50). The 

 other elements in the radium and thorium series which 

 have been investigated are thorium, for which Koczy 

 (1954) gives a figure of 0.02 ppb, and radon, for which 

 Jacobi (1949) gives a range from 1.4 XIO -12 to 2.1 XIO" 12 

 ppb. Protactinium-231, which has the next longest 

 half-life, does not seem to have been detected; the same 

 is true of the elements of the actinium series, which are 

 very scarce. 



Lowder and Solon (1956, p. 13) have summarized 

 the information about naturally occurring radioisotopes 

 other than those of the series discussed above. Their 

 table, abbreviated to those elements which may be 

 reasonably expected to be present in measurable 

 amounts in lake and river waters, is reproduced in table 

 92. Isotopic compositions are not, of course, constant, 

 but will depend on the history of the material analyzed. 

 Marguez and Costa (1955) have detected naturally 

 produced phosphorus-32 and Goel and others (1959) 

 have measured phosphorus-32, phosphorus-33, beryl- 

 lium-17, and sulfur-35 in rain water, so these isotopes 

 probably are to be expected in some lake and river 

 waters also. Data on the tritium content of lakes and 

 rivers have already been presented in table 3. 



Some additional information on radioactivity can be 

 found in Hess (1943 and Love (1951). 



STABLE ISOTOPES 



Apart from hydrogen and oxygen, isotopic ratios are 

 seldom computed for lakes and rivers. It is evident 

 that most, and probably all, chemical elements in the 

 hydrosphere may be expected to show variations in 

 isotopic proportions. Thode, Wanless, and Wallough 



Table 92. — Some singly occurring natural radioisotopes of elements 

 that are chemically delectable in lakes or rivers 



(1954) have demonstrated bacterial fractionation of 

 sulfur isotopes. Such fractionation must produce im- 

 portant hetereogenities in the isotopic composition of 

 sulfur, especially in deep meromictic lakes. To take 

 another example from the hydrosphere, Cameron 

 (1953) has reported significant variations in the Br 79 /Br 81 

 ratio of a number of water samples from various sources. 



ORGANIC MATTER 



The organic content of lake and river waters has 

 been reviewed recently by Hutchinson (1957) and by 

 Vallentyne (1957). Most of what follows is taken from 

 their reviews. 



There does not appear to be any standard method for 

 the determination of the total dissolved-organic content 

 of lake waters, although Hutchinson suggests that loss 

 on ignition of a vacuum-dried sample of filtered water 

 with suitable corrections for loss of chloride and of 

 carbon dioxide from alkaline earth carbonates would 

 provide reasonably accurate figures. The prevalent 

 methods of wet oxidation yield values of the total 

 dissolved-organic material that are about 60 percent too 

 low, to judge from one case that has been critically 

 examined (Hutchinson, 1957, p. 879). 



Birge and Juday (1934) have provided data on the 

 proximate composition of the dissolved organic matter 

 of lake waters from Wisconsin, and have found a steady 

 increase in the C/N ratio with increasing total and 

 dissolved organic carbon content. Some of their data 

 are summarized in table 93. 



From a theoretical analysis of Birge and Juday's 

 results, Hutchinson concluded that the dissolved 

 organic matter in lake waters consists of two fractions, 

 an autochthonous fraction containing about 24 percent 

 crude protein with a C/N ratio of about 12:1, and an 

 allochthonous fraction containing about 6 percent 

 crude protein, with a C/N ratio of 45-50:1. 



Vallentyne (1957) believes that there is substantial 

 evidence for the presence of biotin, glucose, sucrose, 

 thiamin, niacin, and vitamin B 12 dissolved in lake water. 

 In hydrolyzates of dissolved organic matter the amino 

 acids a-alanine, aspartic acid, cystine, glutamic acid, 

 glycine, histidine, tryptophane, and tyrosine have been 



