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Terrestrial ecosystems in low-productivity areas often support biocrusts: plant-like communities composed of cyanobacteria, lichen, and bryophytes. Though diminutive, biocrusts appear to play a crucial role in regulating carbon and nitrogen fluxes on a local scale. However, their biogeochemical contributions on the global scale are poorly understood, and existing estimates are at least a decade-old. In the present study, we examine over 400 previously published biocrust carbon and nitrogen flux values from varying ecosystems. Using bootstrapped geometric mean distributions, we estimate carbon influx to biocrusts at a rate of 3.7 Pg per annum. We also derive a nitrogen influx of 102 Tg per annum, a larger contribution than previously predicted; prior values significantly underestimate flux from plant biocrusts in tropical forests and ground cover in dryland ecosystems. Subsequent sensitivity analysis reveals that employing different temporal, magnitude, respiration, and coverage scaling factors results in upto 86 percent discrepancy between global estimates. Moreover, flux sampling is not geographically diverse, and different ecosystem maps lead to further significant differences. To better refine global estimates of carbon and nitrogen flux from biocrusts, we suggest two directions for future research: sampling flux data from understudied ecosystems and standardizing C and N flux measurement protocol.