20世纪末华北地区冬小麦物候期监测及时空格局分析

Analysis of Winter Wheat Phenological Phase Monitoring andSpatio-temporal Pattern in North China at the End of the 20th Century

基于1983—1999年7 d时间分辨率5 km空间分辨率的AVHRR传感器数据,利用曲线特征点的物候监测方法,反演获得华北地区冬小麦关键物候期并分析其时空演变规律。结果表明:1)冬小麦的拔节期、抽穗期和成熟期主要集中在60—100、105—125和120—155 d。冬小麦物候期空间格局特征和纬度相关,纬度每升高一度冬小麦的拔节期、抽穗期和成熟期分别推迟了5.2、3.5和3.1 d。2)1983年以来,整个研究区的冬小麦物候期呈现提前趋势,每十年冬小麦的拔节期、抽穗期和成熟期分别提前了0.7、3.1、1.9 d。

Based on the AVHRR sensor data with 7-day time resolution and 5 km spatial resolution from 1983 to 1999,the key phenological period of winter wheat in north China was obtained by inversion using the phenological monitoring method of characteristic points of the curve,and its spatio-temporal evolution was analyzed.The results showed that:(1)The jointing stage,heading stage and maturity stage of winter wheat were mainly concentrated in 60—100,105—125,and 120—155 days.The spatial pattern characteristics of winter wheat phenology are related to latitude.The jointing,heading,and maturity periods of winter wheat are delayed by 5.2,3.5,and 3.1 days,while the latitude is increased by one degree;(2)Since 1983,the jointing,heading,and maturity periods of winter wheat are advanced by 0.7,3.1,and 1.9 days per decade.