Abdelrahim Nasser A M, Jin Shuanggen
Shanghai Astronomical Observatory, Chinese Academy of Sciences, Shanghai, 200030, China.
School of Astronomy and Space Science, University of Chinese Academy of Sciences, Beijing, 100049, China.
Environ Monit Assess. 2025 Feb 4;197(3):242. doi: 10.1007/s10661-025-13686-3.
Drought poses a significant threat to agricultural productivity in Africa due to climate variability and water scarcity. To improve drought monitoring using high-resolution remote sensing data, this paper proposes a novel Agricultural Remote Sensing Drought Index (ARSDI). Imagery from Sentinel-1(S-1), Sentinel-2 (S-2), and Landsat 8 was utilized to develop a drought monitoring system for 2017-2023, during which Egypt and Kenya experienced significant drought events. In Kenya, particularly from 2021 to 2023, recurrent droughts severely affected agricultural output, necessitating the evaluation of ARSDI's efficiency in capturing drought severity. Similarly, in Egypt, drought-like conditions linked to reduced Nile River flow and rainfall variability posed significant challenges. ARSDI exhibited strong correlations with traditional drought indicators, such as the Soil Moisture Condition Index (SMCI), ranging from 0.64 to 0.88 in Egypt and 0.74 to 0.85 in Kenya. It also correlated well with the Vegetation Health Index (VHI), with values (0.96 to 0.98) in Egypt and (0.53 to 0.98) in Kenya. Furthermore, ARSDI aligned with Standardized Precipitation Index (SPI), ranging (0.44 to 0.71) in Egypt and (0.47 to 0.60) in Kenya. By integrating Sentinel-1 radar data, ARSDI mitigated the limitations of cloud cover, providing more reliable vegetation monitoring. Compared to other indices, such as the Normalized Difference Vegetation Index (NDVI), ARSDI exhibited superior performance, particularly during the drought events 2019 in Egypt and 2020 in Kenya, demonstrating its robustness in assessing soil moisture and vegetation health.
由于气候多变和水资源短缺，干旱对非洲的农业生产力构成了重大威胁。为了利用高分辨率遥感数据改进干旱监测，本文提出了一种新型的农业遥感干旱指数（ARSDI）。利用哨兵-1（S-1）、哨兵-2（S-2）和陆地卫星8的图像，开发了一个2017-2023年的干旱监测系统，在此期间埃及和肯尼亚经历了重大干旱事件。在肯尼亚，特别是从2021年到2023年，反复出现的干旱严重影响了农业产量，因此有必要评估ARSDI在捕捉干旱严重程度方面的效率。同样，在埃及，与尼罗河流量减少和降雨变化相关的干旱状况带来了重大挑战。ARSDI与传统干旱指标，如土壤湿度状况指数（SMCI）表现出很强的相关性，在埃及范围为0.64至0.88，在肯尼亚为0.74至0.85。它与植被健康指数（VHI）也有很好的相关性，在埃及的值为（0.96至0.98），在肯尼亚为（0.53至0.98）。此外，ARSDI与标准化降水指数（SPI）相符，在埃及范围为（0.44至0.71），在肯尼亚为（0.47至0.60）。通过整合哨兵-1雷达数据，ARSDI减轻了云层覆盖的限制，提供了更可靠的植被监测。与其他指数，如归一化差异植被指数（NDVI）相比，ARSDI表现出卓越的性能，特别是在埃及2019年和肯尼亚2020年的干旱事件期间，证明了其在评估土壤湿度和植被健康方面的稳健性。
