Granulometricheskiy sostav pochv i rykhlykh osadochnykh porod, yavlyayas" fundamental"noy velichinoy, predstavlyaet bol"shuyu vazhnost" dlya ryada zadach pochvovedeniya, melioratsii, a takzhe smezhnykh distsiplin, imeyushchikh otnoshenie k pochve. Problema opredeleniya GMS na protyazhenii poslednikh sta let reshalas" putyem razdeleniya chastits pri ikh sedimentatsii s posleduyushchim raschyetom ikh diametrov po formule Stoksa, odnako v poslednie gody v pochvovedenii, kolloidnoy khimii, drugikh naukakh i praktike stal shiroko vnedryat"sya metod, osnovannyy na yavlenii difraktsii elektromagnitnykh voln, pozvolyayushchiy identifitsirovat" diametr i chislo chastits v analiziruemoy probe nezavisimo ot ikh plotnosti - lazernaya difraktometriya. V rabote privoditsya sravnenie i otsenka rezul"tatov primeneniya metodov pri analize glinistoy fraktsii lesostepnykh pochv, vyyavlyayutsya raskhozhdeniya mezhdu razmerami chastits, opredelyennymi metodom lazernoy difraktometrii i raschitannykh po formule Stoksa, a takzhe otmecheno otsutvie differentsiatsii profilya po soderzhaniyu tonkodispersnykh fraktsiy. Rabota vyzovet interes u nauchnykh rabotnikov, aspirantov i studentov, spetsializiruyushchikhsya v oblasti pochvovedeniya, sedimentologii, okhrany i ratsional"nogo ispol"zovaniya okruzhayushchey sredy.