Fire dominates in determining the distribution of species and guilds. However, the mechanisms driving fire prevalence and activity are still relatively poorly understood, especially over extended timescales.
Researchers from Xishuangbanna Tropical Botanical Garden (XTBG) conducted a study to explore how fire regimes can be studied across long time periods. They used a combination of palynological data, charcoal analysis and integrated that with predictive approaches to understand how the fire regimes have changed over time in a highly heterogeneous region in Northern Southeast Asia.
The researchers used microscopic charcoals from Miocene (23.03 to 5.332 million years ago) sediments in Wenshan Basin (Yunnan, southwestern China) to reconstruct fire dynamics in deep time. Palaeoclimatic data were obtained from the previous quantitative reconstruction using pollen samples from a sedimentary sequence.
Based on the relationships between the charcoals and climatic parameters, the researchers showed that the temperature of the dry/cold period in a year was the main factor in controlling fire frequency during the Miocene. There was significant fire-temperature relationship under the monsoonal climate in Yunnan.
The results of the Maxent (modeling technique) tests showed that temperature in the dry season i the most important parameters and dry season temperature related parameters are the most important factors influencing fire occurrence.
The Maxent also predicted the high probability of active fire mainly located in southern Yunnan. Future increases in fire risk are predicted for most areas across Yunnan.
The study entitled “Fire dynamics under monsoonal climate in Yunnan, SW China: past, present and future” has been published online in Palaeogeography, Palaeoclimatology, Palaeoecology.
Contact
ZHOU Zhekun, Ph.D Principal Investigator
Key Laboratory of Tropical Forest Ecology, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Mengla, Yunnan 666303, China
Tel: 86-871-65109223
E-mail: zhouzk@xtbg.ac.cn
