The role of the soil microbiome in the colonisation of glacier forefields by Antarctic pearlwort (Colobanthus quitensis) under current and future climate change scenarios
The role of the soil microbiome in the colonisation of glacier forefields by Antarctic pearlwort (Colobanthus quitensis) under current and future climate change scenarios
复制标题
DOI：
10.1016/j.soilbio.2023.109249
复制
发表时间：
2023-11-28
影响因子：
9.7
通讯作者：
Molina-Montenegro，Marco A.
中科院分区：
文献类型：
--
作者：
Acuna-Rodriguez，Ian S.;Newsham，Kevin K.;Molina-Montenegro，Marco A.
寒冷地区的冰川消退为植物殖民提供了新的地形。然而，土壤微生物群在新暴露的前田植物建立和表现中的作用很少被评估。在这里，我们比较了在灭菌和未灭菌的土壤中生长了三年的南极珍珠藻(Colobantus Quitensis)个体的存活率，这些土壤最初来自南极三个正在消退的海洋冰川，海拔分别为30米、100米和300米。我们还在一个FOREFIELD上安装了开顶室(OTC)，它使气温提高了∼1.8℃，土壤水势降低了≤-4 kpa，以测试变暖对ONC的影响。对生存和土壤微生物群的敏感。植物表现的主要驱动力是距离冰川锋面的距离，土壤水势下降32千帕，显然解释了300米处植物存活率下降的原因，而冰川则减少了30千帕斯卡。土壤消毒对30米和100米的植物存活几乎没有影响，但在300米的时候减少了存活，这可归因于有益的植物-微生物相互作用的减少。OTCs对植物存活的影响随着距离冰川和消毒的距离而放大，三年后植物在300米的密闭和消毒的土壤中无法存活。土壤细菌功能从30米处的光营养群落转变为100-300米处的专门化异养群落。真菌同源类群在30米处表现出转移RNA和核糖体生物合成的丰富，剪接体和信使RNA的合成在300米处更为频繁。通过增强生理性能，提高存活率，促进物种在新暴露的冰川土壤中的定居。随着未来几十年南极洲海洋气候的变化，这些植物与微生物的相互作用可能会变得越来越重要。
Glacier retreat in cold regions exposes new terrain for plant colonization. However, the roles of soil microbiomes in plant establishment and performance on newly-exposed forefields have rarely been assessed. Here, we compared the survival of Antarctic pearlwort (Colobanthus quitensis) individuals grown for three years in sterilised and unsterilised soils at sites initially at 30 m, 100 m and 300 m from three retreating Maritime Antarctic glaciers. We also installed open top chambers (OTCs), which increased air temperatures by ∼1.8 °C and reduced soil water potential by ≤ 4 kPa, on one forefield to test the effects of warming onC. quitensissurvival and the soil microbiome. The main driver of plant performance was distance from glacier fronts, with a 32 kPa reduction in soil water potential apparently explaining reduced plant survival at 300m compared with 30 m from glaciers. Soil sterilisation had few effects on plant survival at 30 m and 100 m, but reduced survival at 300 m, which was attributable to reductions in beneficial plant-microbial interactions. Effects of OTCs on plant survival were amplified with distance from glacier and sterilisation, with plants not surviving in chambered and sterilised soil at 300 m after three years. Soil bacterial functionality altered from a phototrophic community at 30 m to a more specialized chemoheterotrophic community at 100–300 m. Fungal ortholog groups showed transfer RNA and ribosome biogenesis to be enriched in soil at 30 m, with spliceosomes and messenger RNA synthesis being more frequent at 300 m. We propose that soil microbiomes improve the environmental tolerance ofC. quitensisthrough enhanced physiological performance, which in turn improves survival and facilitates the species’ colonization of newly-exposed glacier forefield soils. These plant-microbe interactions are likely to become increasingly important as the climate of Maritime Antarctica changes over future decades.