Tree-ring growth and stable isotopes (13C and 15N) detect effects of wildfires on tree physiological processes in Pinus sylvestris L. |
| |
Authors: | Rachele Beghin Paolo Cherubini Giovanna Battipaglia Rolf Siegwolf Matthias Saurer Giovanni Bovio |
| |
Institution: | (1) WSL Swiss Federal Research Institute, Z?rcherstrasse 111, 8903 Birmensdorf, Switzerland;(2) Department of AgroSelviTer, Universit? di Torino, Via Leonardo da Vinci, 44, 10095 Grugliasco, Italy;(3) ENEA, via Anguillarese 301, 00123 Rome, Italy;(4) PSI Paul Scherrer Institute, 5232 Villigen, Switzerland; |
| |
Abstract: | Forest fires may alter the physiological and growth processes of trees by causing stress in trees and modifying the availability
of soil nutrient. We investigated if, after a high-severity fire, changes in tree-ring growth can be observed, as well as
changes in the nitrogen and carbon isotope composition of tree rings of surviving trees. Two wildfires that occurred in Pinus sylvestris L. stands in Northern Italy, one at the beginning and one at the end of the vegetative season, were chosen as the focus of
this study. After the fires, the surviving trees showed growth suppression with very narrow tree rings or locally absent rings.
The carbon isotope ratio was more negative in tree rings formed in the 5 years following fire, indicating better water supply
in a situation of less competition. The nitrogen isotope ratio followed opposite trends in the two wildfire stands. In trees
cored in the stand where the fire happened at the beginning of the vegetative season, there was no change in the nitrogen
isotope ratio, whereas in samples collected in the other fire site, higher nitrogen isotope ratios were observed in the tree
rings formed after the fire, reflecting changes in the soil nitrogen supply. Modifications in the growth and isotope composition
of the fire-stressed trees disappeared from 6 to 10 years after the fire. By studying trees before and after fire, we were
able to show that fire affects not only the growth of surviving trees, but also their physiological processes. |
| |
Keywords: | |
本文献已被 SpringerLink 等数据库收录! |
|