Declining Potential Yield and Rain-fed Yield of Corn in the Corn Belt of Northeastern China during the Past Three Decades

摘要

In the past three decades,corn yield in the Corn Belt of North-eastern China(CBNC)have increased under changing in climate and crop management.Quantifying the changes in crop potential production and rain-fed production is essential to determine the yield-contributing and yield-limiting factors and enhance crop productivity.In this paper we conducted correlation and regression analyses of climate and simulated corn yield over the period 1980 to 2011 in CBNC.It was found that the daily minimum temperature and solar radiation were the dominant factor to corn potential production,especially the climate in the post-silking period;the rain-fed production was susceptible to maximum temperature,precipitation,and relative humidity,and the result was showed that relative humidity had a stronger effect than precipitation.According to a regression analysis of the com potential yield and the climate factors,the results indicate that corn potential yield decreased 1010 and 1314 kg ha-1 for each 1°C increase growing season mean and minimum temperature,respectively;rain-fed yield declined 2819 and 2437 kg ha-1 for each increase 1°C growing season mean and maximum temperature,respectively.