Loxton Flux Data Release 2022_v1

This data release consists of flux tower measurements of the exchange of energy and mass between the surface and the atmospheric boundary-layer in semi-arid eucalypt woodland using eddy covariance techniques. It been processed using PyFluxPro (v3.3.3) as described in Isaac et al. (2017), https://doi.org/10.5194/bg-14-2903-2017. PyFluxPro takes data recorded at the flux tower and process this data to a final, gap-filled product with Net Ecosystem Exchange (NEE) partitioned into Gross Primary Productivity (GPP) and Ecosystem Respiration (ER). For more information about the processing levels, see https://github.com/OzFlux/PyFluxPro/wiki.

The Loxton site was established in August 2008 and decommissioned in June 2009. The orchard was divided into 10 ha blocks (200 m by 500 m with the long axis aligned north–south) and the flux tower was situated at 34.47035°S and 140.65512°E near the middle of the northern half of a block of trees. The topography of the site was slightly undulating and the area around the tower had a slope of less than 1.5°. The orchard was planted in 2000 with an inter-row spacing of 7 m and a within row spacing of 5 m. Tree height in August 2008 was 5.5 m. The study block consists of producers, Nonpareil, planted every other row, and pollinators planted as alternating rows of Carmel, Carmel and Peerless, and Carmel and Price. All varieties were planted on Nemaguard rootstock. All but 31 ha of the surrounding orchard was planted between 1999 and 2002. Nutrients were applied via fertigation. Dosing occurred between September and November and in April with KNO3, Urea, KCl, and NH4NO3 applied at annual rates of 551, 484, 647, and 113 kg/ha, respectively. The growth of ground cover along the tree line was suppressed with herbicides throughout the year. Growth in the mid-row began in late winter and persisted until herbicide application in late November.
The research was supported with funds from the National Action Plan for Salinity via the Centre for Natural Resource Management, and the River Murray Levy.This data is also available at http://data.ozflux.org.au .

本数据集发布内容为采用涡度协方差技术（eddy covariance techniques）获取的半干旱桉树林地地表与大气边界层间能量与物质交换的通量塔观测数据。本数据集已通过PyFluxPro（v3.3.3）完成处理，处理流程参照Isaac等（2017）的研究成果（https://doi.org/10.5194/bg-14-2903-2017）。PyFluxPro可将通量塔记录的原始数据处理为最终的间隙填充数据集，并将生态系统净交换量（Net Ecosystem Exchange, NEE）划分为总初级生产力（Gross Primary Productivity, GPP）与生态系统呼吸量（Ecosystem Respiration, ER）。如需了解更多关于处理等级的详细信息，请访问https://github.com/OzFlux/PyFluxPro/wiki。

洛克斯顿（Loxton）观测站点于2008年8月建成并投入观测，2009年6月停运。该果园被划分为若干10公顷的地块（尺寸为200米×500米，长轴沿南北向布置），通量塔设于南纬34.47035°、东经140.65512°处，位于某一林地地块北半部分的近中心位置。站点地形略有起伏，塔台周边区域坡度小于1.5°。该果园于2000年定植，行间间距为7米，行内株间距为5米。2008年8月时，树木平均高度为5.5米。本研究涉及的地块采用交替行种植模式：主栽品种为Nonpareil，授粉品种分别为以Carmel、Carmel与Peerless组合，以及Carmel与Price组合的交替行。所有品种均嫁接于Nemaguard砧木。周边果园除31公顷外，其余地块均于1999年至2002年间完成定植。养分通过滴灌施肥系统施加：每年9月至11月及4月分别施用硝酸钾（KNO3）、尿素（Urea）、氯化钾（KCl）与硝酸铵（NH4NO3），年施用量分别为551、484、647及113千克/公顷。全年均通过除草剂抑制树带沿线地表覆盖植物的生长，行间空地的植被于冬末开始萌发，直至11月下旬喷施除草剂时停止生长。

本研究得到了国家盐度行动计划通过自然资源管理中心以及墨累河征费机制提供的资金支持。本数据集亦可通过http://data.ozflux.org.au 获取。