SOILS — FEBTILIZERS. 717 



Influence of soils and their water contents on nitrogen transformation, 

 F. .MtJNTEB and W. P. Robson (Caitbl. Bakt. [etc.], 2. Abt., 39 {1913), No. 15- 

 17, pp. Jfl9-Jf40; abs. in Internat. Inst. Agr. [Rome], Mo. Dul. Agr. Intel, and 

 Plant Diseases, 5 (1914), No. 2, pp. 192-194; Jour. Che^n. 8oc. [London], 106 

 (1914), No. 616, I, p. 244). — Investigations are reported on the effect of variable 

 water contents and the addition of organic substances on the transformation 

 of organic and inorganic nitrogenous fertilizers in sand, clay, and loam soils. 



Horn meal decomposed more rapidly in dry sand soil than in clay or loam, 

 while with higher water contents there was little difference. Annuonium sul- 

 phate transformation and nitrate formation increased with a higher water con- 

 tent in all of the soils. This was more rapid in clay and loam than in sand 

 when wet. With dry soils the reverse was true. Horn meal ammonia disap- 

 peared rapidly in all of the soils when wet but was retained longer in dry soil, 

 reaching its maximum amount more rapidly the lighter the soil. The fixed 

 absorption of ammonia salts was greater the heavier the soil. The best nitrate 

 formation from horn meal in all cases occurred in the sand soils and was best 

 in clay and loam, with a medium water content. Ammonium sulphate yielded 

 greater quantities of nitrates and more available plant food than horn meal 

 with two exceptions. In general, the largest nitrate formation occurred be- 

 tween the third and sixth weeks except in wet clay. A high water content 

 caused a marked loss of nitrogen from ammonium sulphate in loam and espe- 

 cially from horn meal in clay and loam. 



A liberal addition of sugar so decreased the soluble nitrogen compounds as 

 to cause a deficiency in nitrogen for crops, and caused an increase in nitrate 

 assimilation in all of the soils and a loss of gaseous nitrogen from the sand 

 and loam soils. 



Ammonium sulphate decomposed more rapidly in all of the soils when sugar 

 was added, but there was no corresponding increase in nitrate formation. 



Effect of CS2 and toluol upon nitrification, P. L. Gainey (Centhl. Bakt. 

 [etc.], 2. Abt., 39 {1914), No. 23-25, pp. 584-595, figs. 2; abs. in Jour. Chem. 

 iS'oc. [Lo7idon], 106 {1914), No. 616, I, p. 236). — A previous article on this subject 

 by the same author has already been noted (E. S. R., 30, p. 219). The results 

 of the investigations by the author and other investigators are summarized as 

 follows: 



" The detrimental or beneficial effect of toluol or CS- upon nitrate accumu- 

 lation in soils depends (a) upon acting strength of the chemical in question; 

 and (b) upon whether the soil is exposed for the chemical to evaporate. 



" Toluol, in strengths approximating 0.1 cc. per 100 gm. soil, exerts no appre- 

 ciable effect upon nitrification. If the strength exceeds this it may, and usually 

 does, exert a detrimental or even inhibitory effect upon the process for short 

 periods of incubation. However, if the periods of incubation are extended 

 this harmful effect, which may last as long as 150 days, is overcome with 

 strengths up to and including 1 cc. per 100 gm. soil, the strongest tested. 



" In strengths of less than approximately 1 cc. per 100 gm. soil CS:, even for 

 short periods of incubation, does not exert an appreciable effect upon nitrate 

 accumulation. If the strength exceeds approximately i cc. per 100 gm. soil, 

 CS2 may, and usually does, exert a temporary retarding effect which, however, 

 is soon overcome even with as strong a treatment as 5 cc. per 100 gm. soil. 



" Samples of soil treated with either chemical In sufficient quantity to entirely 

 inhibit nitrification for a period of 4 to 20 weeks may entirely recover from 

 the effect without reinoculation, 



" So far as the results thus far reported from laboratory experimentation 

 can be applied to experimental field practice, it would seem that neither toluol 



