Postglacial fire history and interactions with vegetation and climate in southwestern Yunnan Province of China
A high-resolution, continuous 18.5 kyr (1 kyr = 1000 cal yr BP) macroscopic charcoal record from Qinghai Lake in southwestern Yunnan Province, China, reveals postglacial fire frequency and variability history. The results show that three periods with high-frequency and high-severity fires occur...
| Main Authors: | , , , , , |
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| Format: | Article |
| Language: | English |
| Published: |
Copernicus Publications
2017-06-01
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| Series: | Climate of the Past |
| Online Access: | http://www.clim-past.net/13/613/2017/cp-13-613-2017.pdf |
| Summary: | A high-resolution, continuous 18.5 kyr (1 kyr = 1000 cal yr BP) macroscopic charcoal
record from Qinghai Lake in southwestern Yunnan Province, China, reveals
postglacial fire frequency and variability history. The results show that
three periods with high-frequency and high-severity fires occurred during the
periods 18.5–15.0, 13.0–11.5, and 4.3–0.8 ka, respectively. This record
was compared with major pollen taxa and pollen diversity indices from the
same core, and tentatively related to the regional climate proxy records with
the aim to separate climate- from human-induced fire activity, and discuss
vegetation–fire–climate interactions. The results suggest that fire was
mainly controlled by climate before 4.3 ka and by the combined actions of
climate and humans after 4.3 ka. Before 4.3 ka, high fire activity
corresponded to cold and dry climatic conditions, while warm and humid
climatic conditions brought infrequent and weak fires. Fire was an important
disturbance factor and played an important role in forest dynamics around the
study area. Vegetation responses to fire after 4.3 ka are not consistent
with those before 4.3 ka, suggesting that human influence on vegetation and
fire regimes may have become more prevalent after 4.3 ka. The comparisons
between fire activity and vegetation reveal that evergreen oaks are flammable
plants and fire-tolerant taxa. <i>Alnus</i> is a fire-adapted taxon and a
nonflammable plant, but density of <i>Alnus </i>forest is a key factor to
decide its fire resistance. The forests dominated by
<i>Lithocarpus/Castanopsis</i> and/or tropical trees and shrubs are not
easy to ignite, but <i>Lithocarpus/Castanopsis</i> and tropical trees and
shrubs are fire-sensitive taxa. Fire appears to be unfavourable to plant
diversity in the study area. |
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| ISSN: | 1814-9324 1814-9332 |