关键词: 燕麦, 播期, 需水量, 水分盈亏指数, 降水耦合度

Abstract: To investigate the water demand characteristics of oat in North and Northeast China, the water requirement, moisture loss index, and coupled rainfall degree of early sowing oat (April to July) and late sowing oat (May to August) throughout the whole growing period from 1960 to 2014 were estimated by using SIMETAW model. The results indicated that average water requirement of late sowing oat was less than that of early sowing oat, but average effective rainfall was greater than that of early sowing oat. There were differences in spatial distribution characteristics of water requirement, and the spatial distribution of effective rainfall increased from south to north and from west to east. The moisture loss index of each site was less than 0, showing the effective rainfall of oat during the growth period couldnot meet the water requirement if irrigation is not carried out. The water requirement situations during the growth season of oat did not match the coupled rainfall degree, which caused precipitation to be insufficiently utilized. What’s more, coupled rainfall degree of late sowing oat was greater compared to early sowing oat. Consequently, it was approved to postpone oat date of seeding in time under appropriate soil and climate conditions, which was helpful to make full use of precipitation and reduce irrigation. The results provided reference for rational utilization of water and scientific planting of oat in study areas.

Key words: oat, sowing date, water requirement, moisture loss index, coupled rainfall degree