The wash zone and habitat use among three benthic fish species in stratified lakes

Mixing processes in lakes are important in determining sedimentation zones and in setting the so-called “wash zone”, the area of lake bottom in contact with an oscillating thermocline during wind driven internal seiche events. The wash zone also aligns with a sharp change in sediment roughness and hardness. Taken together these rapid changes in temperature and sediment indicate that the wash zone is a distinctive ecotone in stratified lakes.  Depth stratified randomized netting was used to develop count-based habitat use models for three common benthic fish species as a function of depth or temperature covariates.  Using data from two lakes with quite different wash zone depths, we show the wash zone to describe fish habitat for two of three benthic fish species by utilizing the top 50% of estimated fish abundance as an indicator of habitat use. White sucker (Catostomus commersoni) habitat use was fully within the boundaries of the wash zone. Lake whitefish (Coregonus clupeaformis) habi..., The study focused on Lakes Manitou (46.015; -78.992) and Kioshkokwi (46.078; -78.885) in the northwest corner of Algonquin Park, Ontario, Canada (see Fig. S1 in Supplement). Both are large oligotrophic lakes (Manitou, secchi depth = 2.75 m, TP = 6.6 μg/L; Kioshkokwi, secchi depth = 3.7 m, TP = 7.5 μg/L) with similar morphometries (Manitou, SA = 1,382 ha, max. depth = 38.4 m,  depth = 13.6m; Kioshkokwi, SA = 1,070 ha, max. depth = 47.4 m, depth = 13.9 m). Manitou drains to Kioshkokwi. We evaluate habitat use hypotheses based on mapping of habitat use models stemming from catch data following depth-stratified randomized netting (2 hour soak time per net) in each lake. The netting details are as follows: Gill nets were 64x2 m in total length and height, respectively, composed of 8 single mesh panels (8 m each) sewn together. The mesh series included 2.25 inches (57mm), 2.5” (64mm), 2.75” (70mm), 3.0” (76mm), 3.5” (89mm), 4.0” (102mm), 4.5” (114mm), and 5.0” (127mm) stretch mesh with mono..., , # The wash zone and habitat use among three benthic fish species in stratified lakes The data and code in this Dryad support the re-creation of the analysis in the referenced manuscript. The manuscript contains analysis standardized single-pass benthic gill-netting surveys. Two hour duration benthic gill-nets were used in depth stratified, randomized surveys conducted in two large lakes in Algonquin Provincial Park using standard Summer Profundal Index Netting (SPIN) gillnets. Surveys were conducted during periods of thermal stratification (July-August) in the daytime. Each site was sampled once during a survey. Temperature and DO profiles were collected mid-basin in each lake during the netting surveys. ## Description of the data and file structure Analysis code is provided as .R scripts and is commented. Depth and temperature rasters for mapped analysis are in .Rdata format whereas all other data is in .csv format. .R files can be opened in any R editor, but are best viewed in RSt...湖泊混合过程对于确定沉积区域以及界定所谓的**冲刷带（wash zone）**至关重要。冲刷带指的是在风力驱动的内假潮（internal seiche）事件期间，与振荡温跃层接触的湖底区域。该冲刷带同时对应着沉积物粗糙度与硬度的剧烈变化。综合温度与沉积物的这类快速变化可知，冲刷带是分层湖泊中一类独特的生态交错带（ecotone）。 研究采用深度分层随机网捕作业，基于计数法构建了3种常见底栖鱼类（benthic fish）的栖息地利用模型，该模型以深度或温度作为协变量。本研究利用两个冲刷带深度差异显著的湖泊的数据，以估算鱼类丰度的前50%作为栖息地利用的指示指标，证实冲刷带可用于描述3种底栖鱼类中2种的栖息环境。白吸口鱼（*Catostomus commersoni*）的栖息地利用完全处于冲刷带的边界范围内，湖白鲑（*Coregonus clupeaformis*）的栖息... 本研究聚焦于加拿大安大略省阿尔贡金公园西北角的马尼图湖（46.015; -78.992）与基奥什科维湖（46.078; -78.885）（详见补充材料中的图S1）。两个湖泊均为大型贫营养湖（oligotrophic lake）：马尼图湖塞氏深度（secchi depth）为2.75 m，总磷（TP, Total Phosphorus）浓度为6.6 μg/L；基奥什科维湖塞氏深度为3.7 m，总磷浓度为7.5 μg/L。二者湖泊形态参数相近：马尼图湖表面积（SA）为1382公顷，最大水深38.4 m，平均水深13.6 m；基奥什科维湖表面积为1070公顷，最大水深47.4 m，平均水深13.9 m。马尼图湖的湖水最终汇入基奥什科维湖。 我们基于两个湖泊中深度分层随机网捕作业（每网浸泡时长2小时）获得的渔获数据构建的栖息地利用模型的映射结果，对栖息地利用假说进行验证。采样网具的具体参数如下： 刺网（gill net）总长度为64 m，网高2 m，由8块单块尺寸为8 m的网片缝合而成。网具包含8种拉伸网目尺寸：2.25 inches (57mm), 2.5" (64mm), 2.75" (70mm), 3.0" (76mm), 3.5" (89mm), 4.0" (102mm), 4.5" (114mm), 5.0" (127mm)，网衣材质为单丝... # 分层湖泊中冲刷带与3种底栖鱼类的栖息地利用 本Dryad（Dryad）数据仓库中的数据与代码可复现已发表论文中的分析流程。该论文采用标准化单次底栖刺网调查方法，使用标准夏季深湖指数网（Summer Profundal Index Netting, SPIN）刺网，在阿尔贡金省立公园的两个大型湖泊中开展了深度分层随机采样调查，每网浸泡时长为2小时。调查于热分层时期（7-8月）的日间进行，每个采样点在单次调查中仅采样一次。 采样期间，研究人员在两个湖泊的湖盆中部采集了温度与溶解氧（DO）剖面数据。 ## 数据与文件结构说明 分析代码以带注释的R脚本（.R scripts）形式提供。用于映射分析的深度与温度栅格数据存储为.Rdata格式，其余所有数据均采用逗号分隔值（.csv）格式。R脚本可在任意R编辑器中打开，但最适合在RSt...