Rosvel Bracho Eric Ward John Seiler Brian Strahm Wen Lin Kristin McElligott Jean-Christophe Domec Carlos Gonzalez-Benecke Eric J. Jokela Daniel M. Markewitz Cassandra Meek Guofang Miao Steve G. McNulty John S. King Lisa Samuelson Ge Sun Robert Teskey Jason R. Vogel Rodney E. Will Jinyan Yang Timothy A. Martin Asko Noormets 2021 <p><span>Net primary productivity (NPP) and net ecosystem production (NEP) are often used interchangeably, as their difference, heterotrophic respiration (soil heterotrophic CO</span>₂<span>&nbsp;efflux, R</span>_SH<span>&nbsp;=&nbsp;NPP−NEP), is assumed a near-fixed fraction of NPP. Here, we show, using a range-wide replicated experimental study in loblolly pine (</span><i>Pinus taeda</i><span>) plantations that R</span>_SH<span>&nbsp;responds differently than NPP to fertilization and drought treatments, leading to the divergent responses of NPP and NEP. Across the natural range of the species, the moderate responses of NPP (+11%) and R</span>_SH<span>&nbsp;(−7%) to fertilization combined such that NEP increased nearly threefold in ambient control and 43% under drought treatment. A 13% decline in R</span>_SH<span>&nbsp;under drought led to a 26% increase in NEP while NPP was unaltered. Such drought benefit for carbon sequestration was nearly twofold in control, but disappeared under fertilization. Carbon sequestration efficiency, NEP:NPP, varied twofold among sites, and increased up to threefold under both drought and fertilization.</span></p> application/pdf 10.1029/2020GL092366 en American Geophysical Union Heterotrophic respiration and the divergence of productivity and carbon sequestration article