Noormets, AskoBracho, RosvelWard, Eric J.Seiler, John R.Strahm, Brian D.Lin, WenMcElligott, Kristin M.Domec, Jean-ChristopheGonzález-Benecke, CarlosJokela, Eric J.Markewitz, DanielMeek, CassandraMiao, GuofangMcNulty, Steve G.King, John S.Samuelson, LisaSun, GeTeskey, Robert O.Vogel, Jason G.Will, Rodney E.Yang, JinyanMartin, Timothy A.2021-07-012021-07-012021-04-160094-8276e2020GL092366http://hdl.handle.net/10919/104081Net primary productivity (NPP) and net ecosystem production (NEP) are often used interchangeably, as their difference, heterotrophic respiration (soil heterotrophic CO2 efflux, R-SH = NPP-NEP), is assumed a near-fixed fraction of NPP. Here, we show, using a range-wide replicated experimental study in loblolly pine (Pinus taeda) plantations that R-SH 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-SH (-7%) to fertilization combined such that NEP increased nearly threefold in ambient control and 43% under drought treatment. A 13% decline in R-SH 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.application/pdfenPublic Domaincarbon sequestrationdroughtfertilizationheterotrophic respirationnet ecosystem productionnet primary productionArticle - Refereedhttps://doi.org/10.1029/2020GL0923664871944-8007