Halbach Laura, Kitzinger Katharina, Hansen Martin, Littmann Sten, Benning Liane G, Bradley James A, Whitehouse Martin J, Olofsson Malin, Mourot Rey, Tranter Martyn, Kuypers Marcel M M, Ellegaard-Jensen Lea, Anesio Alexandre M
Department of Environmental Science, iClimate, Aarhus University, Roskilde, Denmark.
Max Planck Institute for Marine Microbiology, Bremen, Germany.
Nat Commun. 2025 Feb 19;16(1):1521. doi: 10.1038/s41467-025-56664-6.
Blooms of dark pigmented microalgae accelerate glacier and ice sheet melting by reducing the surface albedo. However, the role of nutrient availability in regulating algal growth on the ice remains poorly understood. Here, we investigate glacier ice algae on the Greenland Ice Sheet, providing single-cell measurements of carbon:nitrogen:phosphorus (C:N:P) ratios and assimilation rates of dissolved inorganic carbon (DIC), ammonium and nitrate following nutrient amendments. The single-cell analyses reveal high C:N and C:P atomic ratios in algal biomass as well as intracellular P storage. DIC assimilation rates are not enhanced by ammonium, nitrate, or phosphate addition. Our combined results demonstrate that glacier ice algae can optimise nutrient uptake, facilitating the potential colonization of newly exposed bare ice surfaces without the need for additional nutrient inputs. This adaptive strategy is particularly important given accelerated climate warming and the expansion of melt areas on the Greenland Ice Sheet.
深色微藻的大量繁殖通过降低表面反照率加速了冰川和冰盖的融化。然而，养分有效性在调节冰上藻类生长方面的作用仍知之甚少。在这里，我们研究了格陵兰冰原上的冰川冰藻，在添加养分后，提供了单细胞碳：氮：磷（C:N:P）比率以及溶解无机碳（DIC）、铵和硝酸盐同化率的测量值。单细胞分析揭示了藻类生物量中高C:N和C:P原子比率以及细胞内磷储存情况。添加铵、硝酸盐或磷酸盐并不会提高DIC同化率。我们的综合结果表明，冰川冰藻可以优化养分吸收，有助于在新暴露的裸冰表面潜在地定殖，而无需额外的养分输入。考虑到气候加速变暖和格陵兰冰原融化区域的扩大，这种适应性策略尤为重要。
