Terrestrial ecosystems currently sequester around a third of anthropogenic carbon emitted each year, slowing the pace of climate change. However, the future of this sink under rising atmospheric CO2 concentrations remains uncertain, in part due to the impact that nutrient limitation may have on plant biomass. Here, we review plant nutrient acquisition strategies and evidence of the enhanced utilization of these strategies under experimental and real-world elevated CO2 (eCO2). Many of the strategies that are key to nutrient limitation alleviation under eCO2 are not yet well represented in Earth System Models (ESMs). A simple, data-driven analysis implies that ESMs without nutrient acquisition strategies could underestimate the land sink.