Data from: Species-specific effects of biocrust-forming lichens on soil properties under simulated climate change are driven by functional traits

Biocrusts are key drivers of ecosystem functioning in drylands, yet our understanding of how climate change will affect the chemistry of biocrust-forming species and their impacts on carbon (C) and nitrogen (N) cycling is still very limited. Using a manipulative experiment conducted with common biocrust-forming lichens with distinct morphology and chemistry (<i>Buellia zoharyi, Diploschistes diacapsis</i>, <i>Psora decipiens</i> and <i>Squamarina lentigera</i>), we evaluated changes in lichen total and isotopic C and N and several soil C and N variables after 50 months of simulated warming and rainfall reduction. Climate change treatments reduced δ¹³C and C:N ratio in <i>B. zoharyi</i>, and increased δ¹⁵N in <i>S. lentigera</i>. Lichens had species-specific effects on soil dissolved organic N (DON), , β-glucosidase and acid phosphatase activity regardless of climate change treatments, while these treatments changed how lichens affected several soil properties regardless of biocrust species. Changes in thallus δ¹³C, N and C:N drove species-specific effects on DON, , β-glucosidase and acid phosphatase activity. Our findings indicate that warmer and drier conditions will alter the chemistry of biocrust-forming lichens, affecting soil nutrient cycling, and emphasize their key role as modulators of climate change impacts in dryland soils.

生物结皮（biocrust）是旱地生态系统功能的核心驱动因子，但目前学界对气候变化如何影响生物结皮形成物种的化学特征，以及这些物种对碳（C）、氮（N）循环的影响，认知仍十分有限。本研究针对4种具有独特形态与化学特征的常见生物结皮形成地衣——<i>Buellia zoharyi</i>、<i>Diploschistes diacapsis</i>、<i>Psora decipiens</i>和<i>Squamarina lentigera</i>，开展控制实验，评估了50个月模拟增温与减雨处理后，地衣的总碳、总氮及其同位素组成，以及多项土壤碳、氮相关变量的变化。气候变化处理使<i>B. zoharyi</i>的δ¹³C值与碳氮比降低，并使<i>S. lentigera</i>的δ¹⁵N值升高。无论是否施加气候变化处理，地衣对土壤可溶性有机氮（DON）、β-葡萄糖苷酶与酸性磷酸酶活性均具有物种特异性的影响；而气候变化处理则改变了地衣对多项土壤理化性质的影响模式，且该效应不受生物结皮物种类型的制约。地衣体的δ¹³C、氮含量及碳氮比的变化，是导致其对可溶性有机氮、β-葡萄糖苷酶与酸性磷酸酶活性产生物种特异性影响的驱动因素。本研究结果表明，暖干化环境将改变生物结皮形成地衣的化学特征，进而干扰土壤养分循环；同时研究凸显了地衣作为旱地土壤气候变化影响调控者的关键作用。