Soil Fertility Status and Groundwater Suitability Assessment of Ambach Village(Chikhli Taluka), Navsari District, Gujarat

This study characterized soils and assessed groundwater quality for irrigation in Ambach village, Chikhli taluka, Navsari district. Soil samples from 138 locations at two depths (0-20 cm and 20-40 cm) showed slightly alkaline pH on the surface (6.1-8.9, mean 7.8) and subsurface soils (6.5-8.7, mean 7.9), with 93.78% and 96.94% being non-saline, respectively. The SOC levels in the surface soils were 27.53% low, 36.95% medium, and 35.53% high, while those in the subsurface soils were 40.47% low, 37.70% medium, and 21.83% high. Nitrogen was medium in the surface (284.1-329.5 kg ha⁻¹) and medium to low in the subsurface (239.4-290.2 kg ha⁻¹). The P₂O₅ was high in both layers. K₂O in surface soils was 21.9% low, 24.5% medium, and 53.6% high, whereas the subsurface levels were 26.3% low, 34.0% medium, and 39.6% high. The micronutrients Fe, Mn, Zn, and Cu were mostly high, with the nutrient index indicating high fertility for P₂O₅ and K₂O, however, some areas had medium to low fertility. Groundwater assessment of 60 samples (2023-24) from irrigated fields (417 ha, 57% irrigated) revealed pH 7.4-8.4 (mean 7.8) and EC 0.39-1.74 dS m⁻¹ (mean 0.99 dS m⁻¹), with 71.66% classified as high salinity (C3) and 28.33% as medium salinity (C2). SAR ranged from 0.52 to 3.52 (mean 1.33), indicating safe use, while RSC ranged from -0.86 to 7.26 meq L⁻¹ (mean 2.61 meq L⁻¹), posing moderate to high alkalinity risks. Gypsum is recommended to mitigate high SAR and RSC. The study addressed challenges such as high soil variability, limited farmer adoption of organic amendments, and poor irrigation water quality (high EC, RSC). It contributed to sustainable agriculture by providing site-specific nutrient management strategies, promoting organic matter incorporation, and recommending efficient soil and water management practices to enhance soil fertility and crop productivity.