Nov.4. I9I8 Soil Factors Affecting the Toxicity of Alkali 



313 



added and the quantity that was determined by the freezing-point method 

 to be actually in the soil solution. In the case of the added sodium 

 chlorid it was noticeable that there is more salt shown than was added, 

 which indicates either that there was more water than salt adsorbed by 



DqCI Inp-pm- (Sf dry soil 



2P00 J.OOO 



fftOO 



moisture V^Y. 



moisture'^*!. 



• = one plont 



= o.iam. dry matter 



flOjCOt itip.p.mcfdry^oj/ 



SOQ 1.000 iOOO SOOO 1000 lOPOO 



20% ~ 

 moisture 



23% 

 moisture 



2Jf, 



moisture 



27% 



moisture 



moisture "^^^^^^^y^^^A^A^^^I^V^^^ 



* '^ one plant ^*^^ = c.i^m-dry motlcr 



floj 5Qf in pp. m- of dry £oif 

 joo 1.000 sjjooo 5.000 7,000 10000 



moisture ^^vj^jvjfe't^^y^.^^ 



moisture 



25% 



moisture ' 



27"!: 



moisture ' 



21 "7. 



moisture^ _ _ _ 



• = or)e plant ^"^^ = o-iqm ary matter 



Fig. a4.— Diagram showing the number of wheat plants up and the dry matter produced m 21 days in 

 sand and peat maintained at different concentrations and containing sodium clilorid, sodium carbonate, 

 and sodium sulphate added in various concentrations. 



the soil or that other substances were brought into solution from the soil 

 by adding the sodium chlorid. This effect reached a maximum at 2,500 

 p. p. m. of salt. There was no regular difference with the different 

 soil types. In the case of the sulphates, apparently not all of the salt 

 remained in solution except in the lowest concentrations. This was to 



