Page 58 - 《高原气象》2026年第2期

高 原 气 象 45 卷
358

Vegetation Growth Simulations of CLM5.0 in Southwest China

under the 2009 --2010 Drought

1， 2
BING Jiawei ， WANG Lihuan ， LÜ Yaqiong 1
1， 2
（1. Institute of Mountain Hazards and Environment， Chinese Academy of Sciences， Chengdu 610041， Sichuan， China；
2. University of Chinese Academy of Sciences， Beijing 100049， China）

Abstract： Under the influence of global change， drought events have occurred frequently in the originally humid
Southwest region since the 21st century， which has inhibited the growth of vegetation in the region to variable de‐
grees and threatened the security of ecological barriers. In this study， we used the Standardized Precipitation
Evapotranspiration Index （SPEI） to analyze the frequency and characteristics of extreme drought events in South‐
west China from 2001 to 2016. We focused on the 2009 -2010 extreme drought event， which had the longest du‐
ration and the widest spatial impact. The Community Land Model version 5 （CLM5. 0） was employed to numeri‐
cally simulate vegetation growth during this extreme drought event. The applicability of the CLM5. 0 model for
assessing vegetation responses to drought in Southwest China was validated by comparing the simulation results
with three remote sensing datasets （GLASS， GIMMS， and GLOBMAP）. Our results revealed that between
2001 and 2016， there were three extreme drought events lasting more than six months in Southwest China， with
the most prolonged and severe event occurring in 2009 -2010. The CLM5. 0 simulation indicated that during
2009 -2010 extreme drought， CLM5. 0 effectively captured the correlation between vegetation and drought， in‐
cluding lagged responses， cumulative effects， as well as resistance and resilience. The intensity of vegetation re‐
sponse to drought decreased from southeast to northwest， with 68. 66% of regional vegetation exhibiting a
lagged response. Moreover， the lagged response （78. 02%） and cumulative effect （89. 17%） showed large-area
positive correlations with drought， which were consistent with observations from multi-source remote sensing. In
terms of simulating the resistance and resilience of different vegetation types to drought， CLM5. 0 performed rea‐
sonably. Forests exhibited stronger drought resistance compared to shrubs and grasslands， and forests displayed
an inverse trend in resistance and resilience. The validation of CLM5. 0 model simulations with multi-source re‐
mote sensing validation in this study offers a complementary perspective for understanding the multifaceted re‐
sponses of vegetation to drought in Southwest China， contributing to a more comprehensive assessment and pre‐
diction of the impacts of drought on vegetation activities in the region.
Key words： CLM5. 0； extreme drought； drought response； leaf area index； gross primary productivity