Substantial increase of heat requirement for maturity of early rice due to extension of reproductive rather vegetative growth period in China

Zhang, Yaru; Guo, Yahui; Wang, Shuxin; Wu, Wenxiang; Fu, Yongshuo H.

doi:10.1007/S00704-023-04722-8

Title

Substantial increase of heat requirement for maturity of early rice due to extension of reproductive rather vegetative growth period in China

Author

Zhang, Yaru

Guo, Yahui

Wang, Shuxin

Wu, Wenxiang

Fu, Yongshuo H.

Abstract

Climate change has affected crop phenology, leading to changes in agriculture productivity. Previous studies usually take phenology and agriculture as two parallel aspects that climate change would exert influence on, rarely taking the impacts of phenology on agriculture productivity into account. Heat accumulation refers to the sum of the daily average temperature in a certain period, which is an indicator to study the relationship between temperature and the development rate of biological organisms. It indicates the influence of temperature on the growth and development of biological organisms from the aspects of intensity and action time, and is generally calculated by growing degree days (GDD). In this study, trial data on early rice phenology and in situ meteorological data at 48 national agrometeorological experiment stations during 1981 to 2010 were used to investigate the variability of heat accumulation and its driving factors. Using linear function, piecewise function, and sigmoidal function three methods, shifts in heat accumulation during vegetative growth period (VGP), reproductive growth period (RGP), and the whole growth period (WGP) were calculated. Then, the correlations between changes in GDD and (i) three growth durations and (ii) climatic variables were assessed. Our findings indicated that the heat accumulation for early rice was significantly increased by 20% during the WGP, which was mainly attributed to the increase of GDD during the RGP, while GDD during the VGP showed no significant changes. Changes of early rice GDD were closely related to the variations of the RGP duration, which was prolonged by 6.08 day/decade, while VGP duration did not change significantly. Both simple correlation and partial correlation analyses indicated that the positive impacts of growth duration played a dominant role in determining GDD variability, with the average coefficients of 0.91 during VGP, 0.97 during RGP, and 0.93 during WGP, respectively, while temperature played a secondary role. Our studies revealed the dynamics of individual-specific heat accumulation over the past three decades, and emphasized the importance of phenology to agriculture productivity. Therefore, changes in crop phenology should be sufficiently taken into consideration for the better understanding of agriculture dynamics under climate change, and for improving the accuracy of crop model simulation.

Language

English

Source (journal)

Theoretical and applied climatology. - Wien, 1986, currens

Publication

Vienna : Springer wien , 2024

ISSN

0177-798X [print]

1434-4483 [online]

DOI

10.1007/S00704-023-04722-8

Volume/pages