In addition to carrying salt to the ocean, rivers also carry fresh water, which lowers the salinity of seawater near river mouths.
(rivers; also carry; fresh water, which lowers the salinity of seawater near river mouths) (fresh water; lowers; the salinity of seawater near river mouths)
rivers fresh water
also carry lowers
fresh water, which lowers the salinity of seawater near river mouths
the salinity of seawater near river mouths