SPEI-Based Approach to Agricultural Drought Monitoring in Vojvodina Region

Jovana Bezdan,Atila Bezdan,Emilija Nikolić-Đorić,Dragoslav Pavić,Borivoj Pejić,Minučer Mesaroš,Boško Blagojević,Milica Vranešević

doi:10.3390/w11071481

Abstract

This paper presents the standardized precipitation evapotranspiration index (SPEI)-based approach to agricultural drought monitoring (ADM-SPEI approach) combining well-known methods, expert’ 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-SPEIcrop)) in the Vojvodina region. In the first phase of the proposed approach, analytical hierarchy process (AHP) was used to obtain an experts’ 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 ET0 was replaced by ETc. In the validation phase, the results of the application of AD-SPEIcrop were compared to crop yields and well-known indices and evaluated by the experts’ feedback. The statistically significant correlations were achieved between AD-SPEIcrop 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-SPEIcrop better correlates to the crop yields compared to SPEI. The comparison of AD-SPEIcrop 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-SPEIcrop has shown a good performance for agricultural drought monitoring.

Highlights

Drought is a normal feature of climate that occurs in different parts of the world [1] and it is considered to be the most intricate and insufficiently understood natural hazard [2]
If the proposed ADM-standardized precipitation evapotranspiration index (SPEI) approach is applied in some other region, it is necessary to reselect the suitable methods by consulting relevant literature and local experts
Depending on expert individually the results of thetocomparison the validation phase and confirmed their expertise, each expert has individually inspected the results of the comparison in the validation phase and confirmed the consistency of the availabilityofof reliable input data (AD)-SPEIcrop with the compared drought indices. They have confirmed the performance of the AD-SPEIcrop for agricultural drought monitoring

Summary

Introduction

Drought is a normal feature of climate that occurs in different parts of the world [1] and it is considered to be the most intricate and insufficiently understood natural hazard [2]. The character of drought varies in different climates, and its impact depends on the local environmental and socio-economic characteristics [3]. There is neither a universal definition of drought nor a unique index or indicator that applies to all types of drought, climate regimes, or sectors [4]. Tian et al [6] stress that because of the differences in physical characteristics of the environment and crops responding differently to drought conditions, the performance of drought indices varies regarding the application and specific region.

Objectives

Methods

Results

Conclusion