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Drought is one of the most common natural threats to agricultural production worldwide. Few studies have studied the effects of agricultural practices on drought mitigation at a regional scale over a long period. This paper analyzes the spatiotemporal characteristics in the agricultural drought-affected area change index (ADAC), which was developed to assess the drought mitigation. The linear regression method was used to investigate the impact factors on the change of ADAC in the three main winter wheat provinces of northern China. The results showed that the average ADAC during the main growing season in the study area was approximately −61.5% over the past 38 years, which indicated a great decrease of the agricultural drought-affected area. The significant decreasing trends of ADAC values across the study area during 1981–2000 could be explained by the area percentage equipped for irrigation (APEI) by 49.2–89.7%. There was a lack of pronounced change trends of ADAC during 2001–2018, implying that the positive effects of irrigation infrastructure in the plain area might reach a plateau under the constraints of available water resources, and other agricultural practices need to be investigated in the future. This research provides helpful decision information on drought adaptation management and water conservation project planning. [ABSTRACT FROM AUTHOR]

Drought is considered one of the key barriers influencing wheat production, and various adaptation schemes are practiced globally to mitigate drought impacts. However, it is difficult to precisely assess the performances of drought mitigation measures, especially when multiple measures are implemented simultaneously. Here, a remote sensing-based agricultural drought-affected area change index (ADAC) was applied to assess the performance of drought mitigation schemes, which separates and avoids confusion between performances of drought mitigation and wheat yield improvement. The results revealed the historical performance changes and regional differences under drought mitigation measures in 12 major wheat-growing regions (WGRs) of the world. The drought mitigation efforts have steadily succeeded, with a reduction in the drought-affected area of approximately 14.5 % in the 1980s and 28.5 % in the last decade, relatively 55 % of drought-affected areas are alleviated in the 12 WGRs. However, there are significant regional differences ranging from 28 % to 79 % in the 12 WGRs. The drought mitigation measures implemented in the WGRs of China and India, followed by France and Ukraine, are more effective than other regions, while a few are still declining. By further evaluating the effects of short-term and long-term drought mitigation strategies taken in the WGRs, we found that irrigation is the main drought mitigation measure in dryland, while measures such as conservation tillage are of great value for yield stability for both dry and wet areas. The results of this study improve the understanding of the regional performance of drought mitigation schemes and will help stakeholders to select appropriate measures. 1. Relatively 55 % area of drought-affected wheat growing regions are alleviated. 2. Significant regional differences exist in wheat growing regions from 28 % to 79 %. 3. China, India, France and Ukraine are the top 4 countries mitigating wheat drought. 4. Irrigation is the main drought mitigation measure in dryland. 5. Measures of conservation tillage is effective for both dry and wet area. [ABSTRACT FROM AUTHOR]

Droughts can cause tremendous losses to agricultural and economic development; humans have explored many anti-drought measures to mitigate the influence of drought and accordingly altering the characteristics of actual agricultural drought. In this study, a method is proposed to detect the spatiotemporal changes in drought characteristics, which show the effects of anti-drought measures on drought mitigation. Two agricultural drought mitigation evaluation indices are proposed, the agricultural drought frequency change (ADFC) and agricultural drought area change (ADAC), which are calculated by combining the Palmer drought severity index (PDSI) and vegetation health index (VHI), two widely used drought monitoring indices. The PDSI and VHI represent the natural and actual agricultural drought severity under natural and actual conditions respectively, and their differences in drought frequency and affected area reflect the level of anti-drought measures in mitigating agricultural drought. The feasibility of using ADFC and ADAC to quantify the effects of anti-drought measures for agriculture is explored using data from six typical agricultural provinces in the North China Plain and Northeast China. The results show that ADFC and ADAC could reflect both the spatiotemporal changes in agricultural drought characteristics and the influence of anti-drought measures on agricultural drought. The trend of the drought mitigation index is consistent with agricultural activity statistics. These two indices could be further used to evaluate the effects of different anti-drought methods and aid in defeating agricultural drought across many countries. • Assessing drought mitigation performance with changes in drought characteristics • Two drought mitigation indices (ADFC and ADAC) are proposed and tested. • ADAC has the ability to assess mitigation performances to extreme drought event. • PDSI and VHI detect natural and actual agricultural drought separately. [ABSTRACT FROM AUTHOR]