Most problematic are the greatly increased runoff volumes and the ensuing erosion and sediment loadings to surface waters that accompany these changes to the landscape.
(Most problematic; are; the greatly increased runoff volumes and the ensuing erosion and sediment loadings to surface waters) (surface waters; accompany; these changes; to the landscape)
Most problematic surface waters
are accompany
the greatly increased runoff volumes and the ensuing erosion and sediment loadings to surface waters
these changes to the landscape