FTIR Autecological Analysis of Bottom-Ice Diatom Taxa

A recent study demonstrated that a tidal strait, where a shoaled and constricted waterway increases tidally driven sub-ice currents and turbulence, represent ice algal production hotspots due to a hypothesized enhanced ocean-ice nutrient supply. Based on these findings, we sampled the bottom-ice algal community across the same tidal strait between the Finlayson Islands within Dease Strait, Nunavut, Canada in spring 2017. Our objective was to examine sea ice diatom cellular responses to two expected nutrient supply gradients in their natural environment: (1) a spatial gradient across the tidal strait and (2) a vertical gradient up into the bottom-ice matrix. Two diatom taxa, Nitzschia frigida and Attheya spp. within the bottom-ice sections (0-2, 2-5, and 5-10 cm) under thin snow cover (<5 cm) were selected for Fourier Transform Infrared (FTIR) spectrochemical analysis for lipid and protein content. Results from the FTIR technique strongly supported the existence of a spatial nutrient gradient across the tidal strait of the Finlayson Islands, while particulate organic carbon (POC) and chlorophyll a (Chl a) concentration estimates were difficult to interpret. Spatially, the larger N. frigida cells appeared to be more sensitive to the nutrient gradient, significantly increasing (decreasing) in lipid (protein) content towards the outside of the tidal strait. In contrast, the epiphytic diatom, Attheya spp., was more sensitive to the vertical gradient, where above 2 cm into the bottom-ice matrix, the non-motile cells were trapped with a depleted nutrient inventory and evidence of a post-bloom state. Application of the FTIR technique to estimate algal cell biomolecular composition provided new insights on the response of the bottom-ice algal community to the examined nutrient supply gradients that could not be attained from conventional bulk measurements alone. Therefore, future studies are encouraged to employ the use of this technique.

Dataset consists of multiple tabs:

1. Metadata

2. Nitzschia frigida data

3. Attheya spp. data

4. Ice Algae Community

5. Diatom Population

6. FTIR Target Cells

7. Nutrients

8. POC & Chl a

9. PAR

10. Snow & Ice measurements

近期的一项研究表明，潮汐海峡，其中浅滩和狭窄的水道增强了由潮汐驱动的冰下水流和湍流，由于推测的海洋-冰营养供应增强，成为冰藻生产的热点。基于这些发现，我们于2017年春季在加拿大努纳武特地区戴斯海峡的芬利森群岛之间的同一潮汐海峡采集了底冰藻类群落样本。我们的目标是研究海冰硅藻细胞对其自然环境中预期的两种营养供应梯度的反应：一是潮汐海峡的空间梯度，二是垂直梯度，向上延伸至底冰基质。在底冰剖面（0-2、2-5和5-10厘米）中，选择了两个硅藻类群，即Nitzschia frigida和Attheya spp.，在薄雪覆盖（<5厘米）下，用于傅里叶变换红外（FTIR）光谱化学分析，以测定脂质和蛋白质含量。FTIR技术的结果强烈支持了芬利森群岛潮汐海峡存在空间营养梯度的存在，而颗粒有机碳（POC）和叶绿素a（Chl a）浓度估计难以解释。空间上，较大的N. frigida细胞似乎对营养梯度更为敏感，在潮汐海峡的外侧，脂质（蛋白质）含量显著增加（减少）。相反，附着硅藻Attheya spp.对垂直梯度更为敏感，在底冰基质2厘米以上，非游动细胞被困在营养库存耗竭的状态下，并出现后开花的迹象。将FTIR技术应用于估算藻类细胞生物分子组成，为底冰藻类群落对所检查的营养供应梯度的反应提供了新的见解，这些见解无法仅通过传统的总测量获得。因此，鼓励未来的研究采用这种技术。

数据集包含多个标签：

1. 元数据

2. Nitzschia frigida数据

3. Attheya spp.数据

4. 冰藻群落

5. 硅藻种群

6. FTIR目标细胞

7. 营养物质

8. POC & Chl a

9. PAR

10. 雪与冰的测量