Eight Mile Lake Research Watershed, Carbon in Permafrost Experimental Heating and Drying Research (DryPEHR): Fall ecosystem respiration chamber measurements, 2014 - 2017

This drying and warming experiment addresses the following questions: 1) Does ecosystem drying, warming and permafrost thaw cause a net release or uptake of C from the ecosystem to the atmosphere?, 2) Does the decomposition of old C that comprises the bulk of the soil C pool influence ecosystem C loss? 3) How do drying and warmign affect plant communities and ecosystem properties? We are answering these questions using a combined warming and drying experiment (DryPEHR), which is situated with the Carbon in Permafrost Experimental Heating Research (CiPEHR) project and located in an upland tundra field site near Healy, Alaska in the foothills of the Alaska Range. Warming treatment here refers to growing season air temperature warming (~1C) using open top chambers (OTC) combined with soil 'warming' using snow fences during the snow covered months. Drying is achieve using an automated pumping system that lowers the water table in the dry plots. Soil warming began in 2008; OTCs and drying in 2011. This dataset contains static chamber measurements of CO2 flux at DryPEHR during the shoulder season of 2014, 2015, 2016 and 2017.

本干湿增温实验旨在解答以下科学问题：1）生态系统干湿化、增温与永久冻土融化是否会引发生态系统向大气释放或吸收碳的净通量？2）占土壤碳库主体的老碳分解是否会影响生态系统碳流失过程？3）干湿化与增温如何作用于植物群落与生态系统属性？本研究依托永久冻土碳实验加热研究（Carbon in Permafrost Experimental Heating Research, CiPEHR）项目搭建干湿增温实验平台（DryPEHR），实验点位位于阿拉斯加山脉山麓、阿拉斯加州希利镇附近的高地苔原野外站点。本实验的增温处理方案为：生长季采用开顶箱（open top chambers, OTC）实现空气温度增温（约1℃），积雪期则通过雪堤实现土壤增温。干湿化处理通过自动抽水系统降低干燥样地的地下水位。其中土壤增温实验始于2008年，而开顶箱安装与干湿化处理始于2011年。本数据集包含2014、2015、2016及2017年生长季过渡期DryPEHR站点的二氧化碳（CO₂）通量静态箱实测数据。