Crespo Nazaret, Pádua Luís, Paredes Paula, Rebollo Francisco J, Moral Francisco J, Santos João A, Fraga Helder
Centre for the Research and Technology of Agro-Environmental and Biological Sciences (CITAB), Institute for Innovation, Capacity Building, and Sustainability of Agri-Food Production (Inov4Agro), Universidade de Trás-os-Montes e Alto Douro (UTAD), 5000-801 Vila Real, Portugal.
Department of Agronomy, School of Agrarian and Veterinary Sciences, University of Trás-os-Montes e Alto Douro, 5000-801 Vila Real, Portugal.
Sensors (Basel). 2025 Mar 18;25(6):1894. doi: 10.3390/s25061894.
This study investigates the spatial-temporal dynamics of vegetation indices in olive orchards across two traditionally rainfed regions of the Iberian Peninsula, namely the "Trás-os-Montes" (TM) agrarian region in Portugal and the Badajoz (BA) province in Spain, in response to drought conditions. Using satellite-derived vegetation indices, derived from the Harmonized Landsat Sentinel-2 project (HLSL30), such as the Normalized Difference Moisture Index (NDMI) and Soil-Adjusted Vegetation Index (SAVI), this study evaluates the impact of drought periods on olive tree growing conditions. The Mediterranean Palmer Drought Severity Index (MedPDSI), specifically developed for olive trees, was selected to quantify drought severity, and impacts on vegetation dynamics were assessed throughout the study period (2015-2023). The analysis reveals significant differences between the regions, with BA experiencing more intense drought conditions, particularly during the warm season, compared to TM. Seasonal variability in vegetation dynamics is clearly linked to MedPDSI, with lagged responses stronger in the previous two-months. Both the SAVI and the NDMI show vegetation vigour declines during dry seasons, particularly in the years of 2017 and 2022. The findings reported in this study highlight the vulnerability of rainfed olive orchards in BA to long-term drought-induced stress, while TM appears to have slightly higher resilience. The study underscores the value of combining satellite-derived vegetation indices with drought indicators for the effective monitoring of olive groves and to improve water use management practices in response to climate change. These insights are crucial for developing adaptation measures that ensure the sustainability, resiliency, and productivity of rainfed olive orchards in the Iberian Peninsula, particularly under climate change scenarios.
本研究调查了伊比利亚半岛两个传统雨养地区的橄榄园植被指数的时空动态，这两个地区分别是葡萄牙的“Tras-os-Montes”（TM）农业区和西班牙的巴达霍斯（BA）省，以响应干旱条件。利用来自协调陆地卫星哨兵 - 2 项目（HLSL30）的卫星衍生植被指数，如归一化差异水分指数（NDMI）和土壤调整植被指数（SAVI），本研究评估了干旱时期对橄榄树生长状况的影响。专门为橄榄树开发的地中海帕尔默干旱严重指数（MedPDSI）被选来量化干旱严重程度，并在整个研究期间（2015 - 2023 年）评估对植被动态的影响。分析揭示了各地区之间的显著差异，与 TM 相比，BA 经历了更强烈的干旱条件，特别是在温暖季节。植被动态的季节性变化与 MedPDSI 明显相关，在前两个月滞后响应更强。SAVI 和 NDMI 都显示在旱季植被活力下降，特别是在 2017 年和 2022 年。本研究报告的结果突出了 BA 雨养橄榄园对长期干旱诱导压力的脆弱性，而 TM 似乎具有略高的恢复力。该研究强调了将卫星衍生植被指数与干旱指标相结合对于有效监测橄榄园以及改善应对气候变化的用水管理实践的价值。这些见解对于制定确保伊比利亚半岛雨养橄榄园可持续性、恢复力和生产力的适应措施至关重要，特别是在气候变化情景下。
