Rehabilitation Strategy for Restoration of Riverbank Protection Function in the Merawu Watershed, Banjarnegara Regency

Abstract

Abstract Riverbank is a buffer zone for the river ecosystem and the surrounding land. The significant land use changes and land cover reduction in the Merawu Watershed had put pressure on the riverbank and threatened the protection function sustainability. Thus, this study aims to 1) identify the riverbank’s ecological status, 2) identify its Protection Carrying Capacity (PCC), 3) determine the indicative location of rehabilitation, and 4) develop a rehabilitation strategy for restoring the riverbank protection function. The Riparian Quality Index (RQI) results indicated riverbank ecological degradation and deviation from natural conditions due to intensive tillage. The entire riverbank PCC status was poor due to less land cover in dryland agriculture and mixed dryland agriculture. Three indicative locations of rehabilitation were prioritized, i.e., Karangkobar (54.86 ha), Kalibening (41.21 ha), and Wanayasa Sub-districts (39.31 ha). Recommended riverbank rehabilitation strategies were 1) constructing bunds and bench terraces in sloping land, 2) implementing trees along the border (hedgerow) pattern and riparian buffer strips to increase land cover on cultivated riverbank lands, and 3) constructing gully plugs and retaining dams to strengthen riverbanks; using organic mulch; and planting the recommended species (Falcataria falcata, Artocarpus altilis, Dendrocalamus asper, and Gigantochloa apus) on degraded critical lands.