Lower Tunguska vs Nizhnyaya Tunguska River

Lower Tunguska and Nizhnyaya Tunguska River both are nouns.

Word	Noun	Adjective	Verb	Adverb
Lower Tunguska	Yes	No	No	No
Nizhnyaya Tunguska River	Yes	No	No	No

As nouns, Lower Tunguska and Nizhnyaya Tunguska River are synonyms defined as:

Lower Tunguska and Nizhnyaya Tunguska River: a river that arises to the north of Lake Baikal and flows north and west to the Yenisei River

Other synonyms of Lower Tunguska include Tunguska.

Lower Tunguska (noun)	Nizhnyaya Tunguska River (noun)
a river that arises to the north of Lake Baikal and flows north and west to the Yenisei River	a river that arises to the north of Lake Baikal and flows north and west to the Yenisei River