War-Related Changes in Agricultural Land Condition Revealed by Multi-Temporal NDVI, GNDVI and NDMI Analysis

Abstract

Elina Zakharchenko*, Oleksii Bozhonok, Ihor Kovalenko, Viktor Onychko, Stanislav Krokhin and Viacheslav Frolov

War-related disturbance of agricultural land can alter crop development by changing soil physical conditions and surface structure. This study used a nine-year sentinel-2 time series (2017-2025) to examine vegetation responses in farmer-managed fields affected by military activity. Normalized Difference Vegetation Index (NDVI), Green Normalized Difference Vegetation Index (GNDVI), and Normalized Difference Moisture Index (NDMI) were analyzed to characterize changes in canopy development and moisture conditions and to identify spatially persistent anomalies within the fields (Kherson region). The analysis showed that the strongest departures from earlier spatial patterns occurred in 2024-2025, when localized areas of reduced vegetation and moisture indices became more pronounced. These patterns were associated with sectors exposed to military disturbance, including vehicle movement and surface damage, indicating that remote sensing can help delineate zones requiring targeted ground verification. NDVI and NDMI provided the most complementary information for identifying war-related changes in agricultural fields. NDVI effectively reflected changes in vegetation vigor and spatial heterogeneity, whereas NDMI provided additional information on vegetation moisture status and possible alterations in the soil-plant water regime. GNDVI showed generally similar spatial patterns to NDVI and therefore provided more limited additional information in this case. Consequently, combining NDVI and NDMI may be a sufficient and efficient approach for rapid screening of mechanically disturbed agricultural fields, while GNDVI can serve as a supplementary indicator when chlorophyll-related changes are of particular interest.