SPEI-Based Approach to Agricultural Drought Monitoring in Vojvodina Region

• Main Authors: Jovana Bezdan, Atila Bezdan, Boško Blagojević, Minučer Mesaroš, Borivoj Pejić, Milica Vranešević, Dragoslav Pavić, Emilija Nikolić-Đorić
• Format: Article
• Language: English
• Published: MDPI AG 2019-07-01
• Series: Water
• Subjects: drought; agriculture; crop; SPEI; AHP; drought index
• Online Access: https://www.mdpi.com/2073-4441/11/7/1481

This paper presents the standardized precipitation evapotranspiration index (SPEI)-based approach to agricultural drought monitoring (ADM-SPEI approach) combining well-known methods, expert&#8217; critical opinions, and local agro-climatic specificities. The proposed approach has been described in detail in three phases. This allows its application in any region and modification according to different agro-climatic conditions. The application of the ADM-SPEI approach has resulted in obtaining a modified SPEI for different crops (agricultural drought SPEI (AD-SPEI_crop)) in the Vojvodina region. In the first phase of the proposed approach, analytical hierarchy process (AHP) was used to obtain an experts&#8217; group decision regarding the most suitable method for calculating evapotranspiration for a particular analyzed region. In the second phase, SPEI was modified and adjusted to the conditions in Vojvodina, where <i>ET</i>₀ was replaced by <i>ET</i>_c. In the validation phase, the results of the application of AD-SPEI_crop were compared to crop yields and well-known indices and evaluated by the experts&#8217; feedback. The statistically significant correlations were achieved between AD-SPEI_crop and crop yields. The highest correlations were achieved in the months when the analyzed crops were in the developmental stages when they are most sensitive to drought. The AD-SPEI_crop better correlates to the crop yields compared to SPEI. The comparison of AD-SPEI_crop to the standardized precipitation index (SPI), SPEI, and self-calibrated Palmer drought severity index (SC-PDSI) shows that it can successfully detect dry and wet periods. The results have indicated that the proposed approach can be successfully applied, and AD-SPEI_crop has shown a good performance for agricultural drought monitoring.