SOILS FERTILIZERS. 621 



The moisture of typical semiarid and alkali soils in relation to their stage 

 of formation, S. K. Chaianov {Zhur. Opijin. Agron. {Russ. Jour. Expt. 

 Landw.), 12 (1911), No. 3, pp. 321-3J,8, figs. 6).— This article reports the results 

 of observations during 1908, 1909, and 1910 on the moisture of a virgin soil. 

 The vFork is divided into a description of the morphology, mechanical and 

 chemical composition, and flora of the soil, and determinations of the moisture, 

 soluble salts, and carbon dioxid of loam and alkali soils at different depths 

 and seasons of the year. 



It was found that all changes in moisture of alkali soils occurred in the 

 upper layers, not exceeding a depth of 25 cm. (9.85 in.). The water almost 

 never penetrated beyond these layers. 



The moisture of typical semiarid soils varied to a depth of 150 cm. (59.1 in.). 

 There was a pronounced increase in depth of penetration of moisture in spring, 

 and it extended still deeper in summer. During dry years the moisture of 

 typical semiarid and alkali soils was substantially the same, the former being 

 slightly more moist in spring. The moisture content and permeability of alkali 

 soils are determined by the characteristics of the 25 to 35 cm. (9.85 to 13.79 in.) 

 layers. 



The salt content of semiarid loam soils may be decreased by the movement of 

 water in the soil, whereas the salt content of alkali soils continually increases. 



Carbon dioxid in ground air, G. I. Joukow (Khozidlstvo, 6, (1911), No. 2, 

 pp. 37-^6; abs. in Internal. Inst. Agr. [Rome^, Bui. Bur. Agr. Intel, and Plant 

 Diseases, 1911, No. 3, pp. 510, 511). — From a study of factors influencing the car- 

 bon dioxid of soil air the following conclusions were reached : 



" Fallows treated with dry-farming methods of frequent cultivation, in order 

 to maintain moisture and a high temperature in the soil, contain more carbon 

 dioxid than those less cultivated. In April fallows the content of carbon dioxid 

 increases during summer and reaches a maximum in August. This content 

 varies according to depth between a maximum at 30 cm. and a minimum at 

 10 cm. Farmyard manure increases the content of carbon dioxid in the soil. . . . 

 Carbon dioxid accumulates in greater quantity in the air of soils where lucerne, 

 beets, clover, and potatoes are grown than in uncultivated soils. Sandy soils 

 are much less rich in carbon dioxid than those containing organic matter, 

 especially peaty soils." 



On carbon dioxid in ground air, A. Suprunenko (Zap. Novo-Alexsandri. 

 Inst. Selsk. Ehoz. i Lfesov., 21 (1910), No. 1, pp. 59-63; abs. inlnternat. Inst. Agr. 

 \Rome'i, Bui. Bur. Agr. Intel, and Plant Diseases, 1911, No. 3, pp. 511, 512). — 

 The author concludes from his investigations that " the quantity of carbon 

 dioxid contained in the air of the soil is never enough to injure vegetation; it 

 varies according to the nature of the soil. . . . The content of carbon dioxid. 

 in proportion to the depth can only be ascertained on fallow soils, the position 

 and development of roots in cultivated soils causing irregularities. . . . Light 

 rains after a long period of drought increase the carbon dioxid in soils, which 

 shows that they awaken the activity of plants and micro-organisms. Abundant 

 rains produce a contrary effect." 



The production of plant food in the soil, E. J. Russell (Jour. Roy. Agr. 

 Soo. England, 71 (1910), pp. 9-26, figs. 7).— This article is based upon investi- 

 gations on the effect of partial sterilization of soils already noted (E. S. R., 

 22, p. 121), and upon observations as to the growth of various crops in untreated 

 and partially sterilized soils in pots. 



The increased productiveness observed in the partially sterilized soils is 

 ascribed, as in previous papers, primarily to the increased production of am- 

 monia in the treated soils, and this in turn to the destruction by partial steriliza- 



