Analisis Spasial Dampak Lingkungan Akibat ASGM Menggunakan Indeks NDVI dan Fe-Oxide dari Citra Landsat-9 di Kecamatan Lantung, Sumbawa, Indonesia

Ari Nuryaddin Putra; Joni Syafaat; Sukuryadi Sukuryadi

doi:10.59086/jti.v4i3.976

Authors

Ari Nuryaddin Putra Universitas Muhammadiyah Mataram
Joni Syafaat Universitas Muhammadiyah Mataram
Sukuryadi Sukuryadi Universitas Muhammadiyah Mataram

DOI:

https://doi.org/10.59086/jti.v4i3.976

Keywords:

NDVI, Fe Oxide, Pengindraan Jauh, Landsat-9, ASGM

Abstract

Artisanal and Small-Scale Gold Mining (ASGM) di Kecamatan Lantung, Kabupaten Sumbawa, memberikan dampak signifikan terhadap lingkungan, khususnya terhadap kondisi vegetasi dan mineralisasi permukaan. Penelitian ini bertujuan untuk mendeteksi indikasi degradasi lingkungan akibat aktivitas ASGM menggunakan data penginderaan jauh dari satelit Landsat-9. Analisis dilakukan dengan memanfaatkan indeks vegetasi seperti NDVI (Normalized Difference Vegetation Index serta indeks oksida besi (Fe-Oxide) melalui rasio spektral band 4/2 dan 4/3. Hasil penggabungan spasial menunjukkan bahwa zona dengan nilai NDVI ≤ 0.1 dan rasio Fe-oxide tinggi terkonsentrasi pada lokasi pertambangan aktif. Temuan ini mengindikasikan tekanan lingkungan kuat terhadap vegetasi, yang dapat digunakan sebagai indikator awal untuk delineasi wilayah risiko. Total area yang teridentifikasi sebagai zona tekanan lingkungan mencapai ±65,33 hektar dari total area studi ±2.278 hektar. Metodologi ini terbukti efektif untuk pemetaan awal dampak ASGM, khususnya di wilayah minim data laboratorium.

Artisanal and Small-Scale Gold Mining (ASGM) activities in Lantung District, Sumbawa Regency, have significantly impacted the environment, particularly in terms of vegetation condition and surface mineralization. This study aims to detect early signs of environmental degradation caused by ASGM using remote sensing data from the Landsat-9 satellite. The analysis employed vegetation indices such as NDVI (Normalized Difference Vegetation Index) along with an iron oxide index derived from spectral band ratios (Band 4/2 and 4/3). Spatial penggabungan results revealed that zones with NDVI values ≤ 0.1 and high Fe-oxide ratios were concentrated around active mining areas. These findings indicate strong environmental pressure on vegetation, which can serve as an early indicator for delineating risk-prone areas. A total of approximately 65.33 hectares out of the 2,278-hectare study area was identified as environmentally stressed. This methodology proves effective for preliminary ASGM impact mapping, especially in data-scarce regions.

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