LiDAR-based Biomass Estimates, Boreal Forest Biome, Eurasia, 2005-2006

This data set provides estimates of aboveground biomass (AGB) for defined land cover types within World Wildlife Fund (WWF) ecoregions across the boreal biome of eastern and western Eurasia, roughly between 50 and 70 degrees N. The study focused on within-growing-season data, i.e. leaf-on conditions.

The AGB estimates were derived from a series of models that first related ground-based measured biomass to airborne data collected with an Optech Airborne Laser Terrain Mapper (ALTM) 3100, and a second set of models that related the airborne estimates of biomass to Geoscience Laser Altimeter System (GLAS) LiDAR canopy structure measurements. The ground, airborne, and GLAS measurements were used to formulate the models needed to generate biomass predictions for western Eurasia. Eastern Eurasia employed a two-phase approach relating field measurements directly to the GLAS measurements without the airborne intermediary. The GLAS LiDAR biomass estimates were extrapolated by land cover types and ecoregions across the entire biome area.

The study compiled remotely sensed forest structure data collected in June of 2005 and 2006 from the GLAS LiDAR instrument aboard the NASA Ice, Cloud, and land Elevation (ICESat) satellite and from an Optech Airborne Laser Terrain Mapper (ALTM) 3100 airborne instrument flown in Southeast Norway over both the ground plots and the ICESat GLAS flight path. For a consistent biome-level analysis, ecoregions contained within the boreal forest biome were identified by the World Wildlife Fund's (WWF) ecoregion map of the world (Olson et al., 2001). MODIS MOD12Q1 land cover products (2004) were used to identify land cover types for stratification purposes within eco-regions. The ground-based measurements are not provided with this data set.

本数据集提供了全球野生动植物基金会（World Wildlife Fund，简称WWF）所划定的东北亚和西亚寒带生物群落范围内，不同土地覆盖类型的地上生物量（Aboveground Biomass，简称AGB）估计值，大致位于北纬50至70度之间。研究主要关注生长季内的数据，即叶片覆盖状态下的数据。

地上生物量的估计值是通过一系列模型得出的，这些模型首先将地面测量的生物量与使用Optech Airborne Laser Terrain Mapper（ALTM）3100无人机激光地形测绘仪收集的航空数据相关联，其次，另一组模型将航空生物量估计值与地球科学激光测高系统（Geoscience Laser Altimeter System，简称GLAS）的LiDAR冠层结构测量相关联。地面、航空和GLAS的测量数据被用于构建生成西欧亚地区生物量预测所需的模型。东欧亚地区采用了一种两阶段方法，直接将现场测量与GLAS测量相关联，而不经过航空中介。GLAS LiDAR的生物量估计值通过土地覆盖类型和生物群落区域进行了外推。

研究收集了2005年和2006年6月从NASA冰、云和陆地高程卫星（ICESat）上的GLAS LiDAR仪器以及从在挪威东南部运行的Optech Airborne Laser Terrain Mapper（ALTM）3100机载仪器获取的森林结构遥感数据。为了进行一致的生物群落水平分析，使用世界野生动植物基金会（World Wildlife Fund，简称WWF）的世界生物群落地图（Olson et al., 2001）确定了北温带森林生物群落内的生物群落区域。MODIS MOD12Q1土地覆盖产品（2004年）被用于在生态区域内进行土地覆盖类型的分层。本数据集未提供地面测量数据。