Analisis temporal pola sebaran eceng gondok di danau Tondano menggunakan indeks NDVI berbasis citra sentinel 2A sebagai upaya dalam pengelolaan danau

Abstract

Lake Tondano has experienced uncontrolled water hyacinth growth, which has negatively affected water quality and aquatic ecosystems. This study aimed to analyze the distribution and density of water hyacinth and its relationship with environmental factors, particularly wind direction and nutrient availability. The study was conducted using a quantitative descriptive approach with the NDVI method based on multi-temporal Sentinel-2A satellite imagery from 2023 to 2025. The results show that the area of water hyacinth fluctuates over time, covering 324.58 ha in April 2023, decreasing in September, increasing again in October, and reaching the highest extent of 371.82 ha in April 2024, while the lowest area of 205.94 ha occurs in October 2024. Spatially, a distribution shift occurs in 2023, whereas a relatively stable pattern with dominance in the eastern part of Lake Tondano is observed during 2024–2025. These patterns indicate that dominant wind direction and nutrient availability play important roles in controlling the spatial dynamics of water hyacinth in Lake Tondano