Plant phenology refers to long-term adaptation of plant reproduction and growth to changes in light, precipitation, temperature and other conditions, resulting in regular seasonal variability.

Although phenology is a key indicator of climate change, the laws of phenological change of Populus euphratica in arid and semi-arid regions under climate change remain unclear.

Recently, researchers from the Northwest Institute of Eco-Environment and Resources of the Chinese Academy of Sciences (CAS) studied the phenological change of P. euphratica during 1960-2019 to elucidate climate change in the lower reaches of the Heihe River Basin. They also identified the relationship between phenological change and climate change to determine the impact of phenological change on tourism.

Their findings were published in Plant Growth Regulation on Feb. 23.

The results showed that the annual average temperature in the lower reaches of the Heihe River increased significantly over the past 58 years. Thus, the flower bud of P. euphratica opened early, and the time when the leaves turn yellow was delayed.

This proves that temperature is the main environmental factor affecting phenological change, and the length of the growing season was prolonged with the increase of annual average temperature and accumulated temperature.

From 1990 to 2019, the number of frost days for P. euphratica increased, and the number of frost days increased with the length of the growing season.

The results also suggest that the phenological change also affects social economy, especially that the delay of leaf yellow period may has an important impact on tourism since the best viewing period is postponed.