Watershed ecosystem monitoring and evaluation indicators need to factor in land cover/use change rationally and adaptively. Vegetation canopy greenness can be utilized to seek an accurate solution to various land cover/use change issues, for example, by applying the Normalized Difference Vegetation Index (NDVI) algorithm. This research set out to analyze the relationship between the spatial pattern of canopy greenness and small island watersheds’ hydrological characteristics. It used NDVI algorithm extraction and BFLOW+ 3.0 filter in the HydroOffice 12.0 program and then examined the two resulting datasets using correlation analysis. The results showed that the spatial pattern of canopy greenness derived from NDVI changed significantly near the river mouth. The densely populated settlements in the coastal stretch continued to sprawl towards mountainous regions, which naturally function as recharge zones. Meanwhile, the hydrological characteristics displayed a fluctuating trend during the observation period (2015-2019). Based on the correlation analysis, canopy greenness patterns and hydrological features form a positive and relatively strong relationship (38.8%). For this reason, ecological shifts in small island watersheds require climate change mitigation and adaptation measures.

The spatial pattern of canopy greenness tends to experience significant changes in the estuary or river mouth, and in 2019, the densely populated settlements in the coastal stretch had also sprawled into the adjacent mountainous area.

Visualization of hydrological characteristics that shows a fluctuating trend during the study period (2015-2019).

Variations in the spatial pattern of canopy greenness have a positive relationship with the hydrological characteristics of small island watersheds.

Land and water resources management and planning in small islands need to incorporate mitigation and adaptation to any changes in the watershed ecosystems.