CA-TP3 Soil Respiration Data 2017-2019

Soil CO2 emissions or soil respiration (Rs) data were measured at an eastern white pine forest (Pinus strobus L.) planted in 1974 as monoculture stands north of Lake Erie in southern Ontario, Canada. The forest site is part of the Turkey Point Observatory and has been associated with AmeriFlux and global Fluxnet initiatives, where it is known as CA-TP3. Half hourly Rs was recorded using an automated soil CO2 flux measurement system from 2017 to 2019 (excluding winter months). It was comprised of three main components: the gas analyzer (hosted in an analyzer control unit) (LI-8100A), long-term measurement chambers (LI8100-104), and a multiplexer to allow for multiple chamber measurements (LI-8150) (LI-COR Lincoln, Nebraska, USA). Chambers were equipped with a soil temperature (Ts) and soil moisture (SM) probe at 5 cm depth installed outside of the collar. The soil collars had internal diameter of approximately 20 cm, a height of 11.5 cm, and a thickness of 1 cm. Each collar was inserted approximately 7-8 cm into the soil surface, with 3 cm remaining above. The measurement chambers remained open when not taking measurements. Throughout the growing season, any vegetation growth was removed from inside the collars to eliminate potential photosynthesis effects. Tree density is 1583 tree per ha, Leaf Area Index is 6.6, Stand Basal Area is 40.0 m2 ha–1 and above ground biomass is 86.68 t C ha–1. Topography in the area is predominantly flat with occasional 0.5-3.0% undulating slopes. The soil at the site is well drained with a low water holding capacity and classified as brunisolic grey-brown luvisols in the Canadian System of Soil Classification and is composed of ~98% sand. The climate in the region is cool temperate with a 30-year mean annual temperature of 8.0 °C and mean annual precipitation of 1036 mm.<br>本数据集采集自加拿大安大略省南部伊利湖以北、1974年营造的纯林东部白松（Pinus strobus L.）林分的土壤CO₂排放数据，亦称土壤呼吸（soil respiration, Rs）。该林分站点隶属于土耳其角观测站（Turkey Point Observatory），并参与了AmeriFlux与全球通量网（Fluxnet）相关计划，在该计划中编号为CA-TP3。2017至2019年（冬季时段除外），研究团队采用自动化土壤CO₂通量测量系统，以每半小时一次的频率记录Rs数据。该测量系统主要由三部分构成：搭载于分析仪控制单元内的气体分析仪（LI-8100A）、长期测量箱（LI8100-104），以及支持多测量箱测量的多路复用器（LI-8150），设备由美国内布拉斯加州林肯市的LI-COR公司生产。测量箱在环圈外侧安装了深度5cm的土壤温度（soil temperature, Ts）与土壤水分（soil moisture, SM）探头。土壤环圈内径约20cm，高度11.5cm，厚度1cm，每只环圈插入土壤约7-8cm，外露3cm。非测量时段，测量箱保持开放状态。在整个生长季内，研究人员需清除环圈内所有植被，以排除潜在的光合作用影响。该林分的树木密度为1583株/公顷，叶面积指数（Leaf Area Index）为6.6，林分基部面积为40.0 m²·ha⁻¹，地上生物量为86.68 t C·ha⁻¹。区域地形以平坦为主，偶见0.5%~3.0%的缓起伏坡度。该站点土壤排水良好、持水能力较低，按加拿大土壤分类系统归类为灰棕色淋溶始成土（brunisolic grey-brown luvisols），砂粒占比约98%。该区域属冷温带气候，30年平均年温为8.0℃，年平均降水量为1036 mm。