干旱强度及发生时间对华北平原五省冬小麦产量影响

余慧倩,张强,孙鹏,宋长青

Impacts of drought intensity and drought duration on winter wheat yield in five provinces of North China plain

YU Huiqian,ZHANG Qiang,SUN Peng,SONG Changqing

研究区地形、水系、灌区及各省位置与省界示意图

Study area (topography, river system, irrigation and provincial boundary)