03/17/2016

Assessing Earthquake-Induced Tree Mortality in Temperate Forest Ecosystems

A case study looks at the impact of earthquakes and forest dynamics in Wenchuan, China.

The Science

Earthquakes represent a significant driver to forest carbon dynamics. Using a newly developed approach for evaluating post-earthquake disturbance, this study estimates how much biomass carbon loss was associated with the 2008 Wenchuan earthquake in China.

The Impact

This study found that the committed forest biomass carbon loss associated with the May 12, 2008, Wenchuan earthquake (M=7.9) in China was 10.9 Tg C, with the highest tree mortality observed along the fault zone. These findings suggest that earthquake-induced biomass carbon loss should be included in estimating forest carbon budgets.

Summary

Earthquakes can produce significant tree mortality and consequently affect regional carbon dynamics. Unfortunately, detailed studies quantifying the influence of earthquakes on forest mortality are rare. This study assesses the committed forest biomass carbon loss associated with the 2008 Wenchuan earthquake in China with a synthetic approach that integrates field investigation, remote-sensing analysis, empirical models, and Monte Carlo simulations. The newly developed approach significantly improved the forest disturbance evaluation by quantitatively defining the earthquake impact boundary and detailed field survey to validate the mortality models. Based on this approach, a total biomass carbon of 10.9 Tg C was lost in the Wenchuan earthquake, which offset 0.23% of the living biomass carbon stock in Chinese forests. Tree mortality was highly clustered at the epicenter, declining rapidly with distance away from the fault zone. These findings suggest that earthquakes represent a significant driver to forest carbon dynamics, and the earthquake-induced biomass carbon loss should be included in estimating forest carbon budgets.

Principal Investigator(s)

Robinson Negron-Juarez
Lawrence Berkeley National Laboratory
[email protected]

Funding

This study was funded jointly by the Strategic Priority Research Program of the Chinese Academy of Sciences (XDA05050407) and the National Natural Science Foundation of China (41371126). Additional support came from the U.S. Department of Energy, Office of Science, Office of Biological and Environmental Research under Contract Number DE-AC02-05CH11231, as part of the Next-Generation Ecosystem Experiments–Tropics project and Regional and Global Climate Modeling program.

References

Zeng, H., et al. “Assessing earthquake-induced tree mortality in temperate forest ecosystems: A case study from Wenchuan, China.” Remote Sens. 8(3), 252 (2016). DOI:10.3390/rs8030252.