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探讨用ＡＶＨＲＲ／ＬＡＣ资料导出的多时相标准化差异植被指数（ＮＯＶＩ）监测干旱和估计冬麦产量的可能性。对甘肃省１９９１～１９９２年的干旱和造成小麦严重减产的原因进行了分析。结果表明，植被指数的相对变率分布与相应时期的２０ｃｍ土壤相对湿度和降水量的偏差场基本相似，但线性相关系数不高。如果取冬麦生育期的累积植被指数和累积降水量的相对变率则其间的相关系数将提高。冬麦整个生育期全县平均累积ＮＤＶＩ和相应县的冬麦平均每亩产量之间的线性相关已达较高的准确度。
The possibility of monitoring drought and estimating yield of winter wheat using the multi-temporal standardized difference vegetation index (NOVI) derived from the AVHRR / LAC data was discussed. The causes of drought and the serious decrease of wheat yield in Gansu from 1991 to 1992 were analyzed. The results showed that the relative variability of vegetation index was basically similar to that of 20 cm soil relative humidity and precipitation in the corresponding period, but the linear correlation coefficient was not high. The correlation coefficient between the cumulative vegetation index and the cumulative precipitation in the winter wheat growing period will increase. The linear correlation between the average accumulated NDVI of the county and the average yield per mu of winter wheat in the corresponding county during the whole growth period of winter wheat has reached a higher accuracy.