Spatiotemporal characteristics and risk assessment of agricultural drought disasters during the winter wheat-growing season on the Huang-Huai-Hai Plain, China

Abstract

Agricultural drought (AGD) is one of the most impactful natural disasters for rain-fed agricultural regions worldwide, including those in China. Spatiotemporal characteristics of the winter wheat drought season on the Huang-Huai-Hai (HHH) Plain, China, were studied by employing the Penman-Monteith (P-M) equation and a crop coefficient model based on daily meteorological datasets from 57 stations from 1980 to 2011. The crop water deficit index (CWDI) was employed as an index of AGD appraisal to depict the spatiotemporal changes in drought during the winter wheat growth stages in the HHH Plain, China. Besides, this study also intends to develop a drought disaster risk index (DDRI) of winter wheat for various growth stages based on risk formation theory. The spatial distribution patterns indicated higher CWDI values in the northern and middle parts of the HHH Plain and lower in the southern region throughout the wheat growth stages. Of the winter wheat growth stages on the northern HHH Plain, the drought frequency was the highest during the heading-mature stage, when it reached up to 80–100%. The high drought hazard was obvious during the heading-mature growth stage, with a more severe high drought hazard in the northern region of the HHH Plain than in the southern region. Spatially, the high DDRI values were distributed in the northern and central regions of the HHH Plain. The outcomes suggest that the DDRI model provides accurate spatiotemporal appraisals in both temporal and spatial scales, and these findings are important for enhancing the adaptability and mitigation ability of AGD risk on the HHH Plain.