Biological soil crusts (biocrusts) cover ~12% of the global land surface. They are formed by an intimate association between soil particles, photoautotrophic and heterotrophic organisms, and they effectively stabilize the soil surface of drylands. Quantitative information on the impact of biocrusts on the global cycling and climate effects of aeolian dust, however, is not available. Here, we combine the currently limited experimental data with a global climate model to investigate the effects of biocrusts on regional and global dust cycling under current and future conditions. We estimate that biocrusts reduce the global atmospheric dust emissions by ~60%, preventing the release of ~0.7 Pg dust per year. Until 2070, biocrust coverage is expected to be severely reduced by climate change and land-use intensification. The biocrust loss will cause an increased dust burden, leading to a reduction of the global radiation budget of around 0.12 to 0.22 W m⁻², corresponding to about 50% of the total direct forcing of anthropogenic aerosols. This biocrust control on dust cycling and its climate impacts have important implications for human health, biogeochemical cycling and the functioning of the ecosystems, and thus should be considered in the modelling, mitigation and management of global change.

生物土壤结皮（生物结皮）覆盖约 12% 的全球陆地表面。它们是由土壤颗粒、光合自养和异养生物之间的密切结合形成的，它们有效地稳定了旱地的土壤表面。然而，关于生物结壳对风沙尘埃的全球循环和气候影响影响的定量信息尚不可用。在这里，我们将目前有限的实验数据与全球气候模型相结合，以研究生物结壳在当前和未来条件下对区域和全球沙尘循环的影响。我们估计，生物结壳可将全球大气粉尘排放量减少约 60%，从而防止每年释放约 0.7 Pg 粉尘。到 2070 年，预计生物结皮覆盖率将因气候变化和土地利用集约化而严重减少。^-2，相当于人为气溶胶总直接强迫的约 50%。这种对沙尘循环及其气候影响的生物结壳控制对人类健康、生物地球化学循环和生态系统的功能具有重要意义，因此应在全球变化的建模、缓解和管理中加以考虑。