Soil data for cores from a transect from the center of the BBC collapse scar into the surrounding burn

This data set contains soil data for cores from a transect from the center of the BBC collapse scar (0 m) into the surrounding burn (30 m). Thirty-five cores were collected soil cores along the transect in March 2003. We drilled cores using a gasoline powered, permafrost corer while soils were frozen. Two to four cores were drilled every 3 m along the transect, yielding a total of 35 cores. We stored cores frozen and cut sample sections using a radial saw. Cores were sampled at the interfaces between different soil layers. We classified soils using the Canadian Soil Classification system (Soil Classification Working Group 1998) identifying fibric, mesic, and humic organic horizions and the A and C mineral horizons. Nine cores were sampled only to the mineral boundary. We measured bulk density, %C and %N for all soil samples. The pH of sample was determined using litmus paper. We oven-dried at 50 - 65 degC and ground all samples before analysis. We analyzed samples for %C and %N using a Carlo Erba EA1108 CHNS analyzer (CE Instruments, Milan, Italy) and a COSTECH ECS 4010 CHNS-O analyzer (Costech Analytical Technologies Inc., Valencia, CA,USA). Sample standard errors were +/- 0.01% for nitrogen, +/- 0.45% for carbon. To indicate fire events in the surrounding ecosystem, charcoal layers in the cores were quantified. We estimated charcoal by emptying dried samples of a known volume and depth (on mean 4.5 cm3) over a 10 cm x 10 cm grid and counting macroscopic charcoal fragments (greater than 0.05 mm in diameter) in each cm grid cell.

本数据集包含沿样带采集的土壤岩芯数据，样带起点为BBC塌陷坑中心（0 m），延伸至周边火烧区域（30 m处）。2003年3月，研究团队沿该样带采集了35个土壤岩芯：采用汽油驱动的冻土取芯器，在土壤冻结状态下钻取岩芯，每3米布设2~4个采样点，总计获得35个岩芯。所有岩芯均以冷冻状态保存，随后使用径向锯进行切片，并在不同土层的界面处完成采样。本研究采用加拿大土壤分类系统（Canadian Soil Classification system，Soil Classification Working Group 1998）对土壤进行分类，识别出纤维质（fibric）、中质（mesic）与腐殖质（humic）有机层，以及A、C矿质层。其中9个岩芯仅采样至矿质层边界。对全部土壤样品测定了容重、碳百分含量（%C）与氮百分含量（%N）；样品pH值通过石蕊试纸测定。所有样品先在50~65℃条件下烘干并研磨，再开展后续分析。碳、氮含量采用Carlo Erba EA1108型CHNS元素分析仪（Carlo Erba EA1108 CHNS analyzer，意大利米兰CE仪器公司）与COSTECH ECS 4010型CHNS-O元素分析仪（COSTECH ECS 4010 CHNS-O analyzer，美国加利福尼亚州瓦伦西亚Costech分析技术有限公司）完成测定，其中氮含量的样品标准误差为±0.01%，碳含量的样品标准误差为±0.45%。为表征周边生态系统的火烧事件，研究团队对岩芯中的炭屑层进行了定量分析：称取已知体积与深度（平均4.5 cm³）的烘干样品，平铺于10 cm×10 cm的网格之上，计数每个网格单元内直径大于0.05 mm的宏观炭屑碎片，以此估算岩芯中的炭屑含量。