Impacts of temperature on rice yields of different rice cultivation systems in southern China over the past 40 years

摘要

The impact of climate change on rice yield in China remains highly uncertain. We examined the impact of the change of maximum temperature (T-max) and minimum temperature (T-min) on rice yields in southern China from 1967 to 2007. The rice yields were simulated by using the DSSAT3.5 (Decision Support System for Agro-technology Transfer)-Rice model. The change of T-max and T-min in rice growing seasons and simulated rice yields as well as their correlations were analyzed. The simulated yields of middle rice and early rice had a decreasing trend, but late rice yields showed a weak rise trend. There was significant negative correlation between T-max and the early rice yields, as well as the late rice yields in most stations, but non-significant negative correlation for the middle rice yields. An obviously negative relationship was found between T-min and the early and middle rice yields, and a significant positive relationship was found between T-min and the late rice yields. It indicated that under the recent climate warming, the increased T-max brought strong negative impacts on early rice yields and late rice yields, but a weak negative impact on the middle rice yields; the increased T-min had a strong negative impact on the middle rice yields and the early rice yields, but a significant positive impact on the late rice yields. It suggested that it is necessary to adjust rice planting date and adapt to higher T-min. (C) 2015 Elsevier Ltd. All rights reserved.