562 ABSTEACTS 



A Detailed Study of Effects of Climate on Important Properties of Soils. 



C. B. LiPMAN and D. D. Waynick. (Soil Science, 1916, 1, 5^8, 5 



plates.) 



A soil block, 5 feet square and 3 feet deep from the fields of each of 

 three state experiment stations (Maryland, Kansas and California) was 

 moved to the two other experiment stations and placed in position as 

 nearly as possible in the original order of layers. A similar block of soil 

 was dug up and replaced in its position at every station. Strips 5 feet 

 wide of untouched field soil surrounded the board frame of every plot 

 which was placed in position. It was then possible to study at Mary- 

 land, at Kansas and at California four soil blocks as follows: First, nat- 

 ural field soil undisturbed; second, natural field soil disturbed and re- 

 placed; third and fourth, soil blocks obtained respectively from each of 

 the other two stations. The chief aim was to show how any given soil 

 in its natural location compares, after seven years, with the same soil 

 under foreign conditions. Unfortunately no studies except brief chemi- 

 cal studies, were made at the initiation of the soil exchange experiment. 



Studies of the hygroscopic coefficient, the moisture equivalent, the 

 wilting point, changes in color and colloidal nature were among the 

 physical studies made. Among chemical studies, complete chemical 

 analyses were made in accordance with the official method, also humus 

 and humus nitrogen determinations, total nitrogen and soil water-ex- 

 tract studies. Among bacteriological studies were: Counts on albu- 

 men agar, ammonifying power for dried blood, nitrifying power for the 

 soil's own nitrogen, for dried blood, for cotton-seed meal, and for sul- 

 fate of ammonia, nitrogen fixing power in mannit solution, and qual- 

 itative tests for cellulose destruction. 



The soils were described as follows: The California soil as "Sacra- 

 mento silt loam," the Kansas soil as a "dark heavy loam," and the Mary- 

 land soil as a "light yellow clay." 



It was found that soils change markedly in color in a period of seven 

 years, and perhaps less, when moved to other climates. The differ- 

 ences are so great that samples of any one original soil from the three 

 different stations today show no outward resemblance among them- 

 selves, but appear to represent three very distinct soil types. 



In general the hygroscopic coefficient, the moisture equivalent, and 

 the wilting point of any of the soils increased when the soil was placed 

 at California. Some exceptions to this rule are noted. 



Generally speaking bacterial numbers increase in arid soils placed 

 under humid conditions. In general, also, the opposite is true for 

 humid soils. 



Ammonification, nitrification and nitrogen fixation follow the general 

 trend of bacterial counts. In the case of nitrification, however, this 

 applies to certain forms of nitrogen only. In the case of other forms 

 of nitrogen very pecuhar conditions exist which are fully explained in 

 the text. 



Cellulose destruction by soils proceeds with greater rapidity under 

 arid than under humid conditions with any given soil type. Cellulose 



