Degraded landscape dynamics in Gorontalo: implications of land cover change for sedimentation and watershed ecosystem functioning

Abstract

Rapid land cover change in Gorontalo over the past two decades has intensified landscape degradation and accelerated sedimentation processes within watershed ecosystems, particularly in the Lake Limboto catchment. The conversion of forests and riparian vegetation into dryland agriculture, shrublands, and settlements has significantly altered hydrological regimes, increased surface runoff, and exacerbated slope erosion, leading to elevated sediment loads in rivers and lacustrine systems. This study synthesizes empirical evidence through a narrative literature review to examine the relationship between land cover transformation, sediment production, and watershed ecosystem functioning. The review identifies upstream river segments—including the Alo, Biyonga, Batulayar, and Molamahu rivers—as major sediment sources contributing to the accelerated infilling of Lake Limboto. The resulting sediment accumulation has reduced water storage capacity, disrupted hydrological regulation, and degraded aquatic and benthic habitats. The synthesis further highlights that vegetative conservation practices, agroforestry systems, check dams, and integrated watershed management grounded in ecological principles represent the most effective strategies for mitigating sedimentation and restoring ecosystem functions. These findings underscore the urgent need for comprehensive and spatially coordinated landscape management policies to prevent further ecological degradation and ensure long-term watershed sustainability in Gorontalo.