Radial Growth Responses to Climate of Pinus yunnanensis at Low Elevations of the Hengduan Mountains, China

Forests

卷:11

Fernando Jaramillo¹  BjörnE. Gunnarson¹  Yesi Zhao²  Shiyuan Shi²  Yanpeng Cai³  Yang Zhou³  Lian Sun³ 

[1] Department of Physical Geography, Stockholm University, 10691 Stockholm, Sweden;

[2] School of Geography and Ocean Science, Nanjing University, Nanjing 210023, China;

[3] State Key Laboratory of Water Environment Simulation, School of Environment, Beijing Normal University, Beijing 100875, China;

关键词: tree ring;    chronology;    radial growth;    climate;    dry valley;    Hengduan Mountains;   

DOI  :  10.3390/f11101066

来源: DOAJ

【 摘 要 】

The relationship between climate and forest is critical to understanding the influence of future climate change on terrestrial ecosystems. Research on trees at high elevations has uncovered the relationship in the Hengduan Mountains region, a critical biodiversity hotspot area in southwestern China. The relationship for the area at low elevations below 2800 m a.s.l. in the region remains unclear. In this study, we developed tree ring width chronologies of Pinus yunnanensis Franch. at five sites with elevations of 1170–1725 m in this area. Monthly precipitation, relative humidity, maximum/mean/minimum air temperature and the standardized precipitation evapotranspiration index (SPEI), a drought indicator with a multi-timescale, were used to investigate the radial growth—climate relationship. Results show that the growth of P. yunnanensis at different sites has a similar response pattern to climate variation. Relative humidity, precipitation, and air temperature in the dry season, especially in its last month (May), are critical to the radial growth of trees. Supplemental precipitation amounts and reduced mean or maximum air temperature can promote tree growth. The high correlations between chronologies and SPEI indicate that the radial growth of trees at the low elevations of the region is significantly limited by the moisture availability. Precipitation in the last month of the previous wet season determines the drought regime in the following dry seasons. In spite of some differences in the magnitudes of correlations in the low-elevation area of the Hengduan Mountains region, chronologies generally matched well with each other at different elevations, and the differences are not evident with the change in elevation.

【 授权许可】

Unknown