SAFARI 2000 LAI AND FPAR MEASUREMENTS AT SUA PAN, BOTSWANA, DRY SEASON 2000

The Multi-angle Imaging SpectroRadiometer (MISR) Validation team was deployed to the Sua Pan salt playa in the Magkadigkadi region of Botswana during the SAFARI 2000 Dry Season Aircraft Campaign to collect various data sets for validating the MISR LAI/FPAR algorithm. Ground measurements of leaf area index (LAI) and fraction of absorbed photosynthetically active radiation (FPAR) were made using the LAI-2000 plant canopy analyzer and Sunfleck PAR ceptometer, respectively, during focused periods from August 20 to August 28, 2000 at a dry grassland site adjacent to the Sua Pan. The 1 km by 1 km sampling grid was a homogeneous, relatively dense grassland, with a height of 20-100 cm and two prevalent grass types, Odyssea paucinervis and Sporobolus spicatus. Associated reflectance measurements were made with the PARABOLA and ASD instruments (Helmlinger et al., 2004a; 2004b).The data files contain measurements of LAI and PAR reflectance and transmission and a description of sky conditions during the sampling periods. With one exception, all measurements were made under clear sky conditions. PAR data were measured only on the transect scale while LAI are provided at both pixel and transect scales. PAR readings were performed at 93 transect sample points, and LAI readings were performed at 135 (93 transect and 42 subgrid) sample points. Each file also contains mean LAI and PAR values. The data files are ASCII tables, in comma-separated-value format.

多角度成像光谱辐射计（Multi-angle Imaging SpectroRadiometer, MISR）验证团队于2000年SAFARI旱季航空科考活动（SAFARI 2000 Dry Season Aircraft Campaign）期间，部署至博茨瓦纳马卡迪卡迪（Magkadigkadi）地区的苏阿盐坪（Sua Pan salt playa），以采集多套数据集用于验证MISR叶面积指数（Leaf Area Index, LAI）与光合有效辐射吸收比例（Fraction of Absorbed Photosynthetically Active Radiation, FPAR）算法。2000年8月20日至28日的集中观测期内，研究团队在毗邻苏阿盐坪的干旱草原样地，分别使用LAI-2000植物冠层分析仪与Sunfleck型光合有效辐射测量仪开展了叶面积指数与光合有效辐射吸收比例的地面观测。该1km×1km的采样网格覆盖一片均质且相对茂密的草原，株高介于20至100厘米，优势草种为少脉奥德赛草（Odyssea paucinervis）和尖穗鼠尾粟（Sporobolus spicatus）。配套的反射率观测采用PARABOLA与ASD光谱仪完成（Helmlinger等，2004a；2004b）。本数据集包含的数据文件内，记录了叶面积指数、光合有效辐射反射率与透射率的观测值，以及采样时段内的天空状况描述。除一组例外数据外，所有观测均在晴朗天空条件下完成。光合有效辐射数据仅在样带尺度上采集，而叶面积指数数据同时提供像元尺度与样带尺度的结果。研究团队在93个样带采样点开展了光合有效辐射读数采集，在135个采样点（含93个样带点与42个亚网格点）完成了叶面积指数读数采集。每个数据文件同时包含叶面积指数与光合有效辐射的均值。本数据集的文件为采用逗号分隔值（CSV）格式的ASCII表格。