Spatial Distribution of Rice Sowing and Heading Dates in Southern China

摘要

In this paper, we analyzed the spatial distribution of rice key phenology (sowing and heading) dates and the effect of critical temperature (10°Cand 20°C). Agricultural critical temperature was extracted from daily climate data. Spatial distribution characteristics of rice sowing and heading dates were analyzed with ArcGIS. Results showed that the popular dates of rice key phenology changed obviously in space, as well as that of critical temperature. The occurrence of 10°C was more closely related with rice sowing dates, and 20°C with heading dates. The dates of rice sowing and heading stages had similar spatial patterns with that of critical temperature, which meant agricultural critical temperature had great influence on rice development. Climatic gradients along the longitude and longitude directions were associated with that of rice development stages. Rice sowing and heading became late from south to north and also from inland to coast. There was also a large spatial difference in the response of rice phenology to critical temperature changes across the study region. The northwest Sichuan was mainly hilly region, so in this region rice phenology had strikingly different spatial patterns and also different response to critical temperature. The results of our research will provide scientific information for reasonable farming system arrangements and give guidance for future crop breeding.