DETEKSI DAN PREDIKSI SPASIO-TEMPORAL INTRUSI AIR LAUT MENGGUNAKAN INTEGRASI DATA SATELIT DAN MODEL NUMERIK DI KOTA PEKALONGAN (JAWA TIMUR)

• Main Author: Wido Primadipta, Indira
• Format: Theses
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/87257
• Institution: Institut Teknologi Bandung

Soil salinization is the accumulation of soluble salts in soil, which harms agricultural productivity and disrupts ecosystem stability. Globally, about 20% of agricultural land is affected by salinization—a figure projected to reach 50% by 2050 without effective mitigation. In Indonesia, this issue mainly affects coastal regions vulnerable to seawater intrusion and tidal flooding. Pekalongan, a coastal city in Central Java with shallow groundwater systems, is especially susceptible to salinization, shown by increasing groundwater salinity across the city. This study uses an integrative approach, analyzing soil properties including soil type, electrical conductivity (EC), and total soluble salts. We assessed soil salinity levels using Landsat 8 OLI/TIRS satellite imagery, processing it with modified salinity indices calibrated against field data. We conducted spatial-temporal analysis to track salinity trends from 2014 to 2024 and predict future levels up to 2030 using the CA-Markov numerical model (Cellular Automata-Markov Chain), which simulates salinity dynamics based on transition probabilities and environmental factors. Analysis of 44 soil samples revealed significant variations in salinity levels. The northern part of Pekalongan City showed extreme salinity levels (EC 25.9 dS/m, total salts 2,118.26 meq/L), while southern areas remained predominantly nonsaline to slightly saline (EC 0.036 dS/m, total salts 2.74 meq/L). The modified Vegetation Soil Salinity Index (mVSSI) from satellite imagery achieved high accuracy (R² = 0.81 for EC; R² = 0.80 for total salts), confirming the models' reliability in predicting soil salinity. Temporal analysis from 2014-2024 showed fluctuating salinity levels, with significant increases in coastal areas due to tidal flooding and seawater intrusion. The CA-Markov model predicts that by 2030, about 3.04 km² of non-built-up area in Pekalongan City will experience extreme salinity. Areas predicted to have high salinity levels (1.01 to 4.00 dS/m) will cover 1.91 km².