文章基本信息

标题：Tree-ring δ 13C tracks flux tower ecosystem productivity estimates in a NE temperate forest
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作者：Soumaya Belmecheri ; R Stockton Maxwell ; Alan H Taylor 等
期刊名称：Environmental Research Letters
印刷版ISSN：1748-9326
电子版ISSN：1748-9326
出版年度：2014
卷号：9
期号：7
页码：074011
DOI：10.1088/1748-9326/9/7/074011
语种：English
出版社：IOP Publishing Ltd
摘要：We investigated relationships between tree-ring δ¹³C and growth, and flux tower estimates of gross primary productivity (GPP) at Harvard Forest from 1992 to 2010. Seasonal variations of derived photosynthetic isotope discrimination (Δ¹³C) and leaf intercellular CO₂ concentration (c_i) showed significant increasing trends for the dominant deciduous and coniferous species. Δ¹³C was positively correlated to growing-season GPP and is primarily controlled by precipitation and soil moisture indicating that site conditions maintained high stomatal conductance under increasing atmospheric CO₂ levels. Increasing Δ¹³C over the 1992–2010 period is attributed to increasing annual and summer water availability identified at Harvard Forest and across the region. Higher Δ¹³C is coincident with an enhancement in growth and ecosystem-level net carbon uptake. This work suggests that tree-ring δ¹³C could serve as a measure of forest GPP and be used to improve the calibration and predictive skill of ecosystem and carbon cycle models.