Soils can influence climate by sequestering or emitting greenhouse gases (GHG) such as carbon dioxide (CO₂), methane (CH₄), and nitrous oxide (N₂O). We are far from understanding the direct influence of cryptogamic covers on soil GHG fluxes, particularly in areas free of potential anthropogenic confounding factors.

We assessed the role of well-developed cryptogamic covers in soil attributes, as well as in the in-situ exchange of GHG between Antarctic soils and the atmosphere during the austral summer. We found lower values of soil organic matter, total organic carbon, and total nitrogen in bare areas than in soils covered by mosses and, particularly, lichens. These differences, together with concomitant decreases and increases in soil temperature and moisture, respectively, resulted in increases in in-situ CO₂ emission (i.e. ecosystem respiration) and decreases in CH₄ uptake but no significant changes in N₂O fluxes. We found consistent linear positive and negative relationships between soil attributes (i.e. soil organic matter, total organic carbon and total nitrogen) and CO₂ emissions and CH₄ uptake, respectively, and polynomial relationships between these soil attributes and net N₂O fluxes.

Our results indicate that any increase in the area occupied by cryptogams in terrestrial Antarctic ecosystems (due to increased growing season and increasingly warming conditions) will likely result in parallel increases in soil fertility as well as in an enhanced capacity to emit CO₂ and a decreased capacity to uptake CH₄. Such changes, unless offset by parallel C uptake processes, would represent a paradigmatic example of a positive climate change feedback. Further, we show that the fate of these terrestrial ecosystems under future climate scenarios, as well as their capacity to exchange GHG with the atmosphere might depend on the relative ability of different aboveground cryptogams to thrive under the new conditions.

土壤会通过隔离或排放诸如二氧化碳（CO ₂），甲烷（CH ₄）和一氧化二氮（N ₂ O）等温室气体（GHG）来影响气候。我们还远未了解隐秘覆盖对土壤温室气体通量的直接影响，特别是在没有潜在人为混杂因素的地区。

我们评估了发达的隐蔽地被植物在土壤属性中的作用，以及在南半球夏季期间南极土壤与大气之间温室气体原位交换的作用。我们发现，裸露地区的土壤有机质，总有机碳和总氮的价值低于苔藓，特别是地衣覆盖的土壤。这些差异以及随之而来的土壤温度和湿度的降低和升高，分别导致原位CO ₂排放量增加（即生态系统呼吸）和CH ₄吸收量减少，但N ₂没有明显变化。O通量。我们发现土壤属性（即土壤有机质，总有机碳和总氮）与CO ₂排放和CH ₄吸收之间分别具有一致的线性正负关系，这些土壤属性与净N ₂ O通量之间存在多项式关系。

我们的结果表明，陆生南极生态系统中隐孢子虫占据的面积的任何增加（由于生长季节的增加和气候变暖的原因）都可能导致土壤肥力的平行增加以及释放CO _2的能力的增加和减少。吸收CH _4的能力。这些变化，除非被平行的碳吸收过程所抵消，否则将代表积极的气候变化反馈的范例。此外，我们表明，这些陆地生态系统在未来气候情景下的命运以及它们与大气交换温室气体的能力可能取决于不同地上隐球菌在新条件下conditions壮成长的相对能力。