Tree-Ring-Recorded Drought Variability in the Northern Daxing’anling Mountains of Northeastern China

• Main Authors: Jian Yu, Sher Shah, Guang Zhou, Zhenzhao Xu, Qijing Liu
• Format: Article
• Language: English
• Published: MDPI AG 2018-10-01
• Series: Forests
• Subjects: paleoclimatic change; <i>Pinus sylvestris</i> var. <i>mongolica</i>; tree-ring width; PDSI reconstruction; Daxing’anling Mountains
• Online Access: https://www.mdpi.com/1999-4907/9/11/674

We developed two tree-ring width chronologies of Mongolian Scots pine (<i>Pinus sylvestris</i> var. <i>mongolica</i>) from the low elevation forest of the northern Daxing&#8217;anling Mountains of Inner Mongolia. Although the two chronologies come from different sampling sites, significant correlations existed among the chronologies (<i>r</i> = 0.318), and the first principal component (PC1) accounted for 65.9% of total variance over their common period 1792&#8315;2016. Climate-growth correlation analysis revealed that the previous June and July Palmer drought severity index (PDSI_p6-7) was the main climatic factor controlling tree-ring growth. Using a linear regression model, we reconstructed the PDSI_p6-7 for the past 225 years (1792&#8315;2016). The reconstruction satisfied required statistical calibration and validation tests, and represented 38.6% of the PDSI variance recorded by instruments over the period 1955&#8315;2016. Six wet and five dry periods were revealed during these 225 years. The drought of 1903&#8315;1927 was the most severe drought in the study area in the last 225 years. Comparison with other tree-ring-based moisture-sensitive sequences from nearby regions confirmed a high degree of confidence in our reconstruction. The results of a spatial climate correlation analysis with a gridded PDSI dataset revealed that our reconstructions contained strong regional drought signals for the southern Stanovoy Range and the northern Daxing&#8217;anling Mountains. The power spectrum revealed the existence of significant frequency cycles, which may be linked to large-scale atmospheric-oceanic variability, such as the El Ni&#241;o-Southern Oscillation, solar activity, and the North Atlantic Oscillation.