Interactions between Fine Wood Decomposition and Flammability

Forests

Weiwei Zhao¹  Luke G. Blauw¹  Richard S. P. van Logtestijn¹  William K. Cornwell¹ 

[1] Systems Ecology, Department of Ecological Science, Faculty of Earth and Life Sciences, VU University Amsterdam, 1081 HV Amsterdam, The Netherlands; E-Mails:

关键词: carbon cycle;    cellulose: lignin ratio;    forest functioning;    fine woody fuels;    fire;    plant functional traits;    tree;    water dynamics;    wood decay;   

DOI  :  10.3390/f5040827

来源: mdpi

【 摘 要 】

Fire is nearly ubiquitous in the terrestrial biosphere, with profound effects on earth surface carbon storage, climate, and forest functions. Fuel quality is an important parameter determining forest fire behavior, which differs among both tree species and organs. Fuel quality is not static: when dead plant material decomposes, its structural, chemical, and water dynamic properties change, with implications for fuel flammability. However, the interactions between decomposition and flammability are poorly understood. This study aimed to determine decomposition’s effects on fuel quality and how this directly and indirectly affects wood flammability. We did controlled experiments on water dynamics and fire using twigs of four temperate tree species. We found considerable direct and indirect effects of decomposition on twig flammability, particularly on ignitability and burning time, which are important variables for fire spread. More decomposed twigs ignite and burn faster at given water content. Moreover, decomposed twigs dry out faster than fresh twigs, which make them flammable sooner when drying out after rain. Decomposed fine woody litters may promote horizontal fire spread as ground fuels and act as a fuel ladder when staying attached to trees. Our results add an important, previously poorly studied dynamic to our understanding of forest fire spread.

【 授权许可】

CC BY   
© 2014 by the authors; licensee MDPI, Basel, Switzerland.