Sturt Plains Flux Data Release 2024_v1

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).

The site is located on a low lying plain dominated by Mitchell Grass (Astrebla spp.). Elevation of the site is close to 250 m and mean annual precipitation at a nearby Bureau of Meteorology site is 640 mm. Maximum temperatures range from 28.4 °C (in June/ July) to 39.1 °C (in December), while minimum temperatures range from 11.2 °C (in July) to 24.4 °C (in December).

The instrument mast is 5 m tall. Heat, water vapour and carbon dioxide measurements are taken using the open-path eddy flux technique. Temperature, humidity, wind speed, wind direction, rainfall and net radiation are measured. Soil heat fluxes are measured and soil moisture content is gathered using time domain reflectometry.

Ancillary measurements taken at the site include LAI, leaf-scale physiological properties (gas exchange, leaf isotope ratios, nitrogen and chlorophyll concentrations), vegetation optical properties and soil physical properties. Airborne based remote sensing (Lidar and hyperspectral measurements) was carried out at the site in September 2008. Biomass harvest measured: mean live biomass 0.00 gm-2 (standard error: 0.00), mean standing dead biomass 163.42 gm-2 (standard error: 16.73), mean litter biomass 148.99 gm-2 (standard error: 21.32), total mean biomass 312.40 gm-2 (standard error: 30.80). Soil consists of: clay 14.47%, silt 51.23%, sand 34.30%.

本数据集包含采用涡度协方差技术（eddy covariance techniques）获取的地表与大气边界层间能量及物质交换的通量塔观测数据。数据按照Isaac等人（2017年）的研究方法，使用PyFluxPro（v3.4.17）进行处理。PyFluxPro可生成最终的间隙填充数据集，并将净生态系统交换（Net Ecosystem Exchange, NEE）划分为总初级生产力（Gross Primary Productivity, GPP）与生态系统呼吸（Ecosystem Respiration, ER）。该观测站点位于以米切尔草（Astrebla spp.）为优势植被的低洼平原。站点海拔接近250米，邻近的澳大利亚气象局站点年均降水量为640毫米。最高气温介于28.4°C（6/7月）至39.1°C（12月）之间，最低气温则介于11.2°C（7月）至24.4°C（12月）之间。观测塔架高度为5米。采用开路涡度通量技术（open-path eddy flux technique）开展热量、水汽与二氧化碳通量观测。同步测量气温、空气湿度、风速、风向、降雨量与净辐射。同时测定土壤热通量，并通过时域反射仪（time domain reflectometry）采集土壤含水量数据。站点配套观测项目包括叶面积指数（Leaf Area Index, LAI）、叶片尺度生理特性（气体交换、叶片同位素比值、氮与叶绿素浓度）、植被光学特性与土壤物理特性。2008年9月于该站点开展了机载遥感（Lidar与高光谱测量）观测。生物量采样结果如下：活体生物量均值为0.00 g·m⁻²（标准误：0.00），立枯生物量均值为163.42 g·m⁻²（标准误：16.73），枯落物生物量均值为148.99 g·m⁻²（标准误：21.32），总生物量均值为312.40 g·m⁻²（标准误：30.80）。土壤颗粒组成如下：黏粒占比14.47%、粉粒占比51.23%、砂粒占比34.30%。