1. linguistic typology

8. THE DIALECTS OF THE RUSSIAN LANGUAGE
Despite leveling after 1900, especially in matters of vocabulary, a number of dialects exist in Russia. Some linguists divide the dialects of the Russian language into two primary regional groupings, "Northern" and "Southern", with Moscow lying on the zone of transition between the two. Some others divide the language into three groupings, Northern, Central and Southern, with Moscow lying in the Central region. Dialectology within Russia recognizes dozens of smaller-scale variants. The dialects often show distinct and non-standard features of pronunciation and intona­tion, vocabulary and grammar. Some of these are relics of ancient usage now com­pletely discarded by the standard language.
The northern Russian dialects and those spoken along the Volga River typically pronounce unstressed /o/ clearly (the phenomenon called okanye/oKam.e). East of Moscow, particularly in Ryazan Region, unstressed Id and /a/ following palatal­ized consonants and preceding a stressed syllable are not reduced (like in the Moscow dialect), being instead pronounced Id in such positions and many southern dialects have a palatalized final M in 3rd person forms of verbs (this is an unpalatalized sound in the standard dialect) and a fricative where the standard dialect has [r]. However, in certain areas south of Moscow, e.g. in and around Tula, Ivl is pronounced as in the Moscow and northern dialects unless it precedes a voiceless plosive or a pause. In this position /r;/ is lenited and devoiced to the fricative [x], e.g. (drug) (in Moscow's dialect).
The city of Veliky Novgorod has historically displayed a feature called chokanye/ tsokanye , where /tS;/ and /ts/ were confused. Among the first to study Russian dialects was Lomonosov in the eighteenth century. In the nineteenth, Vladimir Dal compiled the first dictionary that included dialectal vocabulary. Detailed mapping of Russian dialects began at the turn of the twentieth century. In modern times, the monumental Dialectological Atlas of the Russian Language, was published in three folio volumes 1986-1989, after four decades of preparatory work.
Most Russians can easily understand any of dialects of the native language, unlike Chinese or Indians. The standard language is based on (but not identical to) the Moscow dialect.