Abstract:

In order to investigate the change rule of cotton phenology under the background of climate change, the parameters of the cotton growth model COSIM were adjusted and verified to achieve localization. Using mathematical statistics and crop model simulation methods, the response and sensitivity of cotton phenological periods to climate change were analyzed. The results showed that from 1980 to 2019, the date of emergence, budding and flowering of cotton in Xinjiang were earlier by 0.5-7.0 d/10a, 0.1-5.8 d/10a, and 0.3-3.9 d/10a, respectively, and the date of boll opening was delayed by 0.1-4.7 d/10a. COSIM was used to simulate phenological changes of cotton, and the results were consistent with the actual changes. The RMSE of the actual and simulated values of the date of emergence, budding, flowering and boll opening was 0.9 d, 0.7 d, 0.6 d and 0.7 d, respectively. Under warmer climate (simulated warming 0.5℃, 1℃, 1.5℃ and 2℃ compared with the base climate condition of 1981—2010), the rate of growth and development of cotton increased and each phenological period became earlier. The date of emergence, budding, flowering and boll opening were earlier by 0-2 d, 1-9 d, 2-12 d and 3-31 d, respectively; the vegetative growth stage and reproductive growth stage were shortened by 0-6 d and 2-22 d, respectively. Therefore, through variety selection and technology adjustment, climate warming can give more potential productivity to cotton by utilizing the advantage of heat and avoiding disaster risk in the key phenological periods, in order to achieve high yield and efficiency of cotton production.

Key words: cotton, climate change, phenology, COSIM model, Xinjiang