Analisis Zona Pengelolaan Nitrogen Spesifik Lokasi Berbasis Indeks Vegetasi NDVI, NDRE, dan SAVI dari Citra Satelit Sentinel 2A pada Lahan Pertanian Kecamatan Sumbersari

Abstract

Nitrogen is an essential macronutrient that plays an important role in plant growth and productivity. This study aimed to analyze the spatial distribution of vegetarian indices and determine site-specific nitrogen management zones based on NDVI, NDRE, and SAVI derived from Sentinel-2A satellite imagery in Sumbersari District, Jember Regency. This research employed a quantitative descriptive approach using 33 soil samples collected through purposive sampling. Vegetation indices were generated using ArcGIS, while total soil nitrogen was analyzed in the laboratory. Multiple linear regression was applied to evaluate the relationship between vegetation indices and soil nitrogen, whereas nitrogen distribution was mapped using the Inverse Distance Weighted (IDW) interpolation method and classified into five management zones using the Quantile method. The results showed that NDVI, NDRE, and SAVI exhibited spatial variability across the study area, while total soil nitrogen ranged from 0.091% to 0.470%. The regression analysis produced the equation N = 0.213 − 6.031(NDVI) − 0.768(NDRE) + 4.487(SAVI) with an R² value of 0.078 and a significance value of 0.493, indicating a weak relationship between vegetation indices and total soil nitrogen. Nevertheless, the spatial analysis successfully classified the study area into five site-specific nitrogen management zones that can support precision fertilization.