Altıkat (2025) Satellite-Driven Evaluation of Moisture Dynamics for Irrigation Management in a Semi-Arid Apple Orchard

Identification

• Journal: Journal of Agriculture
• Year: 2025
• Date: 2025-12-29
• Authors: Alperay Altıkat
• DOI: 10.46876/ja.1700703

Research Groups

Iğdır University, Faculty of Agriculture, Department of Biosystems Engineering, Iğdır, Türkiye

Short Summary

This study evaluated moisture dynamics and water stress in a semi-arid apple orchard over six years (2020-2025) using integrated satellite-derived spectral (NDWI, NDMI) and thermal (ET) indices to inform precision irrigation management. It revealed critical water stress periods and spatial variability, advocating for data-driven, adaptive strategies to enhance water-use efficiency and drought resilience.

Objective

• To evaluate moisture variability and hydrological stress in a semi-arid apple orchard using integrated satellite-derived spectral (NDWI, NDMI) and thermal (ET) indices over a six-year period (2020-2025) to support data-driven irrigation management.

Study Configuration

• Spatial Scale: A commercial apple orchard covering 63,107 square meters.
• Temporal Scale: Six-year analysis from 2020 to 2025, focusing on the May–October plant growth season annually.

Methodology and Data

• Models used: Normalized Difference Water Index (NDWI), Normalized Difference Moisture Index (NDMI), and satellite-based Evapotranspiration (ET) models.
• Data sources: Remote sensing data obtained from the Farmonaut® Crop Health Monitoring platform, processing Sentinel-2 Level-2A surface reflectance products.

Main Results

• The orchard experienced critical water stress in 2020 and 2022, characterized by low canopy and surface moisture (e.g., 94% of the orchard area had NDWI values between -1 and 0.1 in 2022) coinciding with intensified atmospheric water loss (e.g., over 40,000 square meters affected by high ET in 2020).
• 2025 represented a year of partial hydrological recovery, with improved spectral responses (e.g., 57% of the field in 0.2–0.3 NDWI range, 91% in 0.2–0.3 NDMI range) aligning with significantly lower evapotranspiration intensity (over 46,000 square meters in Low and Very Low ET zones).
• The year 2024 exhibited a notable anomaly where, despite low moisture indicators (over 72% of the field had NDMI values below 0.1), vegetation performance was sustained, suggesting localized water-use efficiency or unobserved subsurface retention mechanisms.
• Spatial mapping revealed distinct dry zones recurring across years, primarily in the northern and eastern sectors of the orchard, highlighting the need for spatially adaptive irrigation practices.
• The combined index approach provided a more nuanced understanding of water distribution patterns and hydrological dynamics than any single metric alone, effectively differentiating periods of decline and recovery.

Contributions

• Provides a replicable and scalable remote sensing framework for precision irrigation management in semi-arid orchard systems.
• Enhances field-level decision-making by integrating spectral moisture indices (NDWI, NDMI) with thermal water loss metrics (ET) to assess soil-plant-atmosphere interactions.
• Supports the reduction of irrigation inefficiencies and enhances resilience to climate-induced water challenges in fruit production.
• Contributes to the operational use of remote sensing in precision agriculture by demonstrating the diagnostic potential of synchronized multi-index evaluation for monitoring climatic fluctuations and informing regional irrigation strategies.

Funding

The study was supported under the 2209-A University Students Research Projects Support Program, conducted by the TÜBİTAK (BİDEB).

Citation

@article{Altıkat2025SatelliteDriven,
  author = {Altıkat, Alperay},
  title = {Satellite-Driven Evaluation of Moisture Dynamics for Irrigation Management in a Semi-Arid Apple Orchard},
  journal = {Journal of Agriculture},
  year = {2025},
  doi = {10.46876/ja.1700703},
  url = {https://doi.org/10.46876/ja.1700703}
}