华北地区冬小麦产量预报模式的初步研究

本文提出了一种省级以上尺度的作物-天气产量预报模式。首先,对气候产量进行R-型聚类分析,将全区分成若干亚区;然后,用累加型及阶乘型的多重非线性回归方法组建预报方程。本文提出的模式,原则上可以适用于多种尺度和不同作物,预报时效也可以根据生产需要和作物发育阶段的特点给定。 华北地区冬小麦产量预报的时效,分为冬前、越冬后及黄熟前三个阶段。预报方程的复相关系数,分别可达到0.70,0.90和0.95以上;平均相对剩余误差为15％,8％和4％。

A PRELIMINARY STUDY OF YIELD FORECAST MODEL FOR WINTER WHEAT IN NORTH CHINA

The paper presents a crop-weather model for yield prediction on provincial level and higher. First, North China area is divided into a number of subregions by the R-type cluster analysis of climatic yield. Based on different effective of forecast period (EFP),correlations between climate yield and weather factor for each area are computed to sieve out forecast factors. Finally, forecast equations are established using the method of nonlinear multi-regression of accumulated and factorial type. The model may be applied to different crops, the EFP can be adopted according to characteristics of crops development stage or preduction needs.The EFP of winter wheat yield forecast in Norther China is divided into three phases: before wintering, after wintering and before ripeness. The multiple correlation coefficients are larger than 0.70,0.90 and 0.95 for the forecasts of the three different EFP respectively. The correlation error is below 1500,8% and 4% respectively.