DataSheet_1_Description and Spatial Modelling of Benthic Communities Distribution in the Canadian Arctic Archipelago.zip

In the Arctic, sea ice loss has already transformed the dominant sources and periodicity of primary production in some areas, raising concerns over climate change impacts on benthic communities. Considered to be excellent indicators of environmental changes, benthic invertebrates play important roles in nutrient cycling, sediment oxygenation and decomposition. However, this biological component of the Canadian Arctic Archipelago (CAA) is still somewhat poorly studied compared to other Arctic regions. To partly fill this need, this study aims to evaluate benthic community composition and its relationship to significant environmental drivers and to develop spatial predictive explanatory models of these communities to expand coverage between sampled stations across the Kitikmeot Sea region and Parry Channel. Results from previously collected samples suggest that biodiversity is higher in this region compared to the Beaufort and Baffin Seas, two adjacent regions to the West and East, respectively. This finding leads to the main hypothesis that (1) benthic communities are succeeding one another, forming an ecotone (transition area) between the Beaufort Sea and the Baffin Sea. Other hypotheses are that (2) Pacific Ocean water influence through the CAA can explain part of this gradient, and that (3) terrigenous inputs affect the distribution of species. Overall, results tend to confirm hypotheses. Generalized Linear Models (GLMs) (with R2 up to 0.80) clearly displayed a succession in community distribution from Queen-Maud Gulf (Southwest) to Lancaster Sound (Northeast). Such models can be useful in identifying potential biodiversity hotspots and as a baseline for marine spatial planning purposes. Further, Pacific origin water (traced with concentrations of nitrate relative to phosphate) and terrigenous inputs (traced with silicate concentrations) were related to species and community distribution. Given that these two inputs/factors are generally increasing in the Canadian Arctic, their influence on benthic communities may also be seen to increase in the upcoming years.

在北极地区，海冰消退已在部分区域改变了初级生产力的主要来源与周期，引发了人们对气候变化对底栖生物群落（benthic community）影响的担忧。底栖无脊椎动物（benthic invertebrates）被视为环境变化的优质指示生物，在营养盐循环、沉积物氧化与分解过程中发挥着重要作用。然而，相较于其他北极区域，加拿大北极群岛（CAA）的这一生物组分仍有待深入研究。为部分填补这一研究空白，本研究旨在评估底栖生物群落组成及其与关键环境驱动因子的关联，并构建针对这些群落的空间预测解释模型，以扩展基蒂克美奥特海与帕里海峡区域采样站位间的覆盖范围。此前采集的样本结果显示，相较于西侧的波弗特海与东侧的巴芬海这两个邻近海域，本研究区域的生物多样性更为丰富。这一发现引出了核心假说：（1）底栖生物群落呈现连续更替状态，在波弗特海与巴芬海之间形成了生态交错带（ecotone，过渡区域）。其余假说包括：（2）经加拿大北极群岛输入的太平洋海水可部分解释这一分布梯度；（3）陆源输入会影响物种的分布格局。总体而言，研究结果验证了上述假说。决定系数（R²）最高可达0.80的广义线性模型（Generalized Linear Models, GLMs）清晰展现了群落分布从西南的女王莫德湾到东北的兰开斯特海峡的连续更替规律。此类模型可用于识别潜在的生物多样性热点区域，同时可作为海洋空间规划的基准参照。此外，以硝酸盐与磷酸盐浓度比值示踪的太平洋源海水，以及以硅酸盐浓度示踪的陆源输入，均与物种及群落分布存在关联。鉴于加拿大北极区域的这两类输入/因子整体呈上升趋势，未来它们对底栖生物群落的影响或将进一步增强。