Establishment and characteristics analysis of a crop–drought vulnerability curve: a case study of European winter wheat

摘要

As an essential component of drought risk, crop–droughtvulnerability refers to the degree of the adverse response of a crop to adrought event. Different drought intensities and environments can causesignificant differences in crop yield losses. Therefore, quantifying droughtvulnerability and then identifying its spatial characteristics will helpunderstand vulnerability and develop risk-reduction strategies. We selectthe European winter wheat growing area as the study area and 0.5°?×?0.5° grids as the basic assessment units. Winter wheatdrought vulnerability curves are established based on theerosion–productivity impact calculator model simulation. Their loss changeand loss extent characteristics are quantitatively analysed by the keypoints and cumulative loss rate, respectively, and are then syntheticallyidentified via K-means clustering. The results show the following. (1)?Theregional yield loss rate starts to rapidly increase from 0.13 when thedrought index reaches 0.18 and then converts to a relatively stable stagewith the value of 0.74 when the drought index reaches 0.66. (2)?In contrastto the Pod Plain, the stage transitions of the vulnerability curve lagsbehind in the southern mountain area, indicating a stronger tolerance todrought. (3)?According to the loss characteristics during the initial,development, and attenuation stages, the vulnerability curves can be dividedinto five clusters, namely low-low-low, low-low-medium,medium-medium-medium, high-high-high, and low-medium-high loss types,corresponding to the spatial distribution from low latitude to high latitudeand from mountain to plain. The paper provides ideas for the study of theimpact of environment on vulnerability and for the possible application ofvulnerability curve in the context of climate change.