Petr Samsonovich Kossovich

Born Sept. 16 (28), 1862, in Gorky, in present-day Mogilev Oblast; died Aug. 13 (26), 1915, in Petrograd. Russian agricultural chemist and agrologist.

Kossovich graduated from Moscow University in 1887 and the Petrov Academy of Agriculture and Forestry in 1889. He worked at Moscow University (1891-94) and became a professor at the St. Petersburg Institute of Forestry in 1902. In 1897, Kossovich organized an agricultural-chemical laboratory to study the chemical properties of Russian soils. In 1900 he founded Zhurnal opytnoi agronomii (Journal of Experimental Agronomy); it continued to appear until 1931. He served as elected director of the St. Petersburg Institute of Forestry (1905-07 and 1909-11). He demonstrated (1889-91) that legumes take up free nitrogen only through roots that have nodules and showed that physiologically acid ammonia fertilizers in combination with rock phosphate act as a solvent. In 1896, Kossovich found (in sterile cultures) that plants can take up ammonium cations without changing them into nitric acid anions. Kossovich was the first in Russia to investigate the sulfur and chlorine cycles in nature (1913). He examined the evolution of soils in relation to change in the conditions of soil formation.