Effects of temperature and precipitation on litterfall phenology in four evergreen broad‐leaved forests of southern China

Abstract Vegetative and reproductive growth of subtropical and tropical forests plays an important role in regulating carbon cycle and maintaining food web dynamic balance. Here, we used litterfall and climatic data during 1998–2017 at four evergreen forest sites in southern China to analyze temporal variations of community phenology and their climate drivers. Results show that two southwest forests have unimodal patterns with leaf litterfall peaks during dry season, while two southeast forests have bimodal patterns with the first peaks during rainy season and the second peaks during rainy and dry seasons respectively. Peaks of flower litterfall for the four forests occurred during the transitional period between dry and rainy seasons, while peaks of fruit litterfall appeared either at the end of the rainy season at the two southern sites or in the dry season at the two northern sites. Leaf litterfall correlates significantly positively with preseason maximum temperature at the four sites, but significantly negatively with preseason precipitation at two southwest sites. By contrast, flower and fruit litterfall correlates significantly positively with preseason temperature and precipitation at only three and two sites. Moreover, leaf, flower, and fruit litterfall exhibits a 12‐month cycle, which is consistent with the 12‐month cycle of monthly temperature and precipitation. Flower and fruit litterfall displays also multiyear cycles between 18 and 48 months, however, it is inconsistent with the multiyear cycles of monthly temperature and precipitation. Our study highlights that temperature and precipitation are key factors affecting litterfall variations in different time scales in southern China. Abstract in Chinese is available with online material.