Microbial respiration in laboratory soil incubations, Agashashok River, Alaska, 2019

The position of the Arctic treeline is an important regulator of surface energy budgets, carbon cycling and subsistence resources in high latitude environments. It has long been thought that temperature exerts a direct control on growth of treeline trees and the position of the treeline. However, our recent work on white spruce in the Arctic suggests that indirect effects of temperature on tree access to soil nutrients may be of equal or greater importance. Our recent results provide correlative evidence of the importance of winter snow depth as a driver of tree growth. The aim of this project was to experimentally isolate the importance of snow depth and soil nutrient availability and examine the consequences for microbial processes, tree growth and treeline advance.
This dataset contains measurements of microbial respiration made over time during a 3-month laboratory incubation in which soils were held at a range of temperatures (-10, -6, -2, 2 and 6 degrees Celsius (deg C)) crossed with a range of labile carbon additions (0, 0.2, 0.4 and 2 milligrams of carbon per gram of dry soil (mg C per g dry soil)).

北极林线（Arctic treeline）的位置是高纬度环境中地表能量平衡、碳循环及生存资源的重要调节因子。长期以来，人们认为温度对林线树木的生长及林线位置具有直接调控作用。然而，我们近期针对北极白云杉（white spruce）的研究表明，温度对树木获取土壤养分有效性（soil nutrient availability）的间接影响可能具有同等或更重要的作用。我们的近期研究结果提供了相关性证据，表明冬季积雪深度是树木生长的重要驱动因子。本项目的目的是通过实验分离积雪深度与土壤养分有效性的重要性，并探究其对微生物过程、树木生长及林线推进的影响。

本数据集包含3个月实验室培养期间随时间测定的微生物呼吸（microbial respiration）数据，培养过程中土壤置于一系列温度条件下（-10、-6、-2、2及6摄氏度（deg C）），并与一系列易变碳（labile carbon）添加量（0、0.2、0.4及2毫克碳每克干土（mg C per g dry soil））交叉组合。