Alice Springs Mulga Flux Data Release 2024_v2

<p>This release consists of flux tower measurements of the exchange of energy and mass between the surface and the atmospheric boundary-layer using eddy covariance techniques. Data were processed using PyFluxPro (v3.4.17) as described by Isaac et al. (2017). PyFluxPro produces a final, gap-filled product with Net Ecosystem Exchange (NEE) partitioned into Gross Primary Productivity (GPP) and Ecosystem Respiration (ER). <br />The Alice Springs Mulga flux station is located on Pine Hill cattle station, approx. 170&nbsp;km north of Alice Springs in the Northern Territory. The woodland is characterised by a mixed <em>Acacia aneura</em> and <em>Acacia aptaneura</em> canopy, with a total standing biomass of 32.5 t/ha and median canopy height of 4.3&nbsp;m (tallest trees reach 8.9&nbsp;m height). Elevation of the site is 602&nbsp;m above sea level, and the terrain is flat. Mean annual precipitation at the nearby (45&nbsp;km distant) Bureau of Meteorology station is 311&nbsp;mm - 140&nbsp;mm (1986-2025), but has ranged between 33&nbsp;mm in the hydrological years of 2018/2019 to 712&nbsp;mm in 2016/2017 since the tower is operational. Predominant wind directions are from the southeast and east. The extent of the woodland is 11&nbsp;km to the east of the flux station and 16&nbsp;km to the south. The soil is characterised as a red kandosol (74:11:15 sand:silt:clay) overlying an approx. 50&nbsp;m deep water table. Pine Hill Station is a functioning cattle station that has been in operation for longer than 50 years. Fluxes of heat, water vapour and carbon are measured using the open-path eddy covariance technique at 11.6&nbsp;m. Supplementary measurements above the canopy include temperature and humidity (11.6&nbsp;m), downwelling and upwelling shortwave and longwave radiation (12.2&nbsp;m). Precipitation is monitored in a canopy gap near the tower (2&nbsp;m). Supplementary measurements below the canopy include barometric pressure (1&nbsp;m) and temperature and humidity (2&nbsp;m). Below ground soil measurements are made in bare soil, mulga, and understory habitats and include ground heat flux (0.08&nbsp;m), soil temperature (0.02&nbsp;m &ndash; 0.06&nbsp;m) and soil moisture (0 &ndash; 0.1&nbsp;m, 0.1 &ndash; 0.3&nbsp;m, 0.6 &ndash; 0.8&nbsp;m and 1.0 &ndash; 1.2&nbsp;m).</p>

本数据集包含采用涡度协方差（eddy covariance）技术获取的地表与大气边界层间能量与物质交换通量塔观测数据。数据采用PyFluxPro（v3.4.17）进行处理，处理流程参照Isaac等人（2017）的研究方法。PyFluxPro可生成最终的间隙填充数据集，将生态系统净交换（Net Ecosystem Exchange，简称NEE）划分为总初级生产力（Gross Primary Productivity，简称GPP）与生态系统呼吸（Ecosystem Respiration，简称ER）。
爱丽丝斯普林斯穆尔加通量站位于派恩希尔畜牧场，地处北领地爱丽丝斯普林斯以北约170公里处。该林地以Acacia aneura与Acacia aptaneura的混交冠层为特征，总现存生物量达32.5吨/公顷，冠层高度中位数为4.3米（最高树木可达8.9米）。该站点海拔为602米，地形平坦。距离该站约45公里的澳大利亚气象局站点的多年平均降水量为311毫米（1986-2025年），但自通量塔投用以来，年降水量波动范围为2018/2019水文年的33毫米至2016/2017水文年的712毫米。主导风向为东南风和东风。该林地的覆盖范围以通量站为起点，向东延伸11公里、向南延伸16公里。该站点土壤为红色强风化粘磐土（red kandosol），砂粒、粉粒、粘粒占比为74:11:15，地下水位埋深约50米。派恩希尔畜牧场为运营时长超50年的在用畜牧场。研究采用开路式涡度协方差技术，在11.6米高度处观测热通量、水汽通量与碳通量。冠层上方的补充观测项目包括：11.6米高度处的气温与湿度，以及12.2米高度处的下行、上行短波辐射与长波辐射。塔体附近的冠层空隙处（2米高度）设有降水监测装置。冠层下方的补充观测项目包括：1米高度处的大气压力，以及2米高度处的气温与湿度。地下土壤观测分别在裸地、穆尔加金合欢林地以及林下生境开展，观测项目包括：0.08米深度处的土壤热通量，0.02米至0.06米深度范围内的土壤温度，以及0-0.1米、0.1-0.3米、0.6-0.8米、1.0-1.2米深度的土壤含水量。