First pollen-based REVEALS reconstruction of vegetation abundance in Europe for five time windows between 6k years BP and present

The submitted dataset includes the pollen-based REVEALS estimates of 11 plant functional types (PFTs) and 3 land-cover types (LCTs) for Europe, published in Trondman et al. (2015) as part of the results from the Swedish project LandClim I (Gaillard et al., 2010). In this project, pollen-based REVEALS estimates of land cover for 5 time windows of the Holocene were used to evaluate the scenarios of anthropogenic land-cover change (ALCC) KK and HYDE (Kaplan et al., 2017) and to study the biogeophysical forcing of ALCC between the time windows 6200-5700 years BP and CE 1600-1850 (Strandberg et al., 2014). The reconstruction is based on 25 pollen taxa for which pollen productivity of the corresponding plant taxa were available. The taxa included in the 11 PFTs and 3 LCTs are shown in Table 1 of Trondman et al. (2015). The REVEALS estimates for the 25 individual taxa will be submitted later. See details on the REVEALS model (Sugita, 2007) under "The REVEALS model".

The REVEALS data files
The LandClim I pollen-based REVEALS reconstructions of land cover are gridded with a cell size of 1°. The file LandClim I LCTs.xls contains the REVEALS estimates of the cover of three land-cover types (LCTs), Evergreen Trees (ET), Summer-green Trees (ST) and Openland (OL). The file LandClim I PFTs.xls contains the REVEALS estimates of the cover of 11 plant functional types (PFTs) (see folder "Metadata" in the excel file for details). In both excel files, the folder "Metadata" contains the explanation of abbreviations in the data folders, the folder "Sitedata" is the Metadatafile of the pollen records used for the REVEALS reconstructions, and there are 10 REVEALS data/results folders of which the first five folders contain the REVEALS estimates for the five time windows of the LandClim I project, and the last five folders contain the corresponding standard errors (SEs) on the REVEALS estimates. All REVEALS estimates and their SEs are given in proportions of the grid cell (the total of all REVEALS estimates sum up to 1). In each data/results folder, the columns LCGRID and LCGRID_ID are project internal IDs, the column "cell" is the coordinate of the upper left (NW) corner of the grid, and the column "Cell label" is the country number of the grid cell with REVEALS data/results. In the file LandClim I LCTs.xls, the five folders "....BPmeanLC" contain the REVEALS estimates of the three land-cover types for the five time windows, and the five folders "....BPSE" contain the standard errors (SE) on the LCT REVEALS estimates. In the file LandClim I PFTs.xls, the five folders "....BPmeanLC" contain the REVEALS estimates of the 11 plant functional types for the five time windows, and the five folders "....BPSE" contain the standard errors (SE) on the PFT REVEALS estimates.

本次提交的数据集涵盖欧洲地区11种植物功能型（Plant Functional Types, PFTs）与3种土地覆盖型（Land Cover Types, LCTs）基于孢粉的REVEALS估算结果，该成果作为瑞典LandClim I项目（Gaillard等人，2010年）的研究成果之一，发表于Trondman等人（2015年）的研究中。在该项目中，研究人员针对全新世5个时间窗口的土地覆盖基于孢粉的REVEALS估算结果，用于评估人为土地覆盖变化（Anthropogenic Land-Cover Change, ALCC）情景KK与HYDE（Kaplan等人，2017年），并探究公元前6200-5700年与公元1600-1850年两个时间窗口之间人为土地覆盖变化的生物地球物理强迫效应（Strandberg等人，2014年）。本次重建基于25个孢粉类群，相关植物类群的孢粉生产力数据均可获取。11种植物功能型与3种土地覆盖型所涵盖的类群详见Trondman等人（2015年）的表1。25个单类群的REVEALS估算结果将后续提交。关于REVEALS模型的详细信息，请参阅"The REVEALS model"章节（Sugita, 2007年）。

REVEALS数据集文件
LandClim I项目基于孢粉的土地覆盖REVEALS重建结果采用1°分辨率的网格进行网格化处理。文件LandClim I LCTs.xls包含3种土地覆盖型的覆盖度REVEALS估算结果，分别为常绿乔木（Evergreen Trees, ET）、夏绿乔木（Summer-green Trees, ST）与开阔地（Openland, OL）。文件LandClim I PFTs.xls包含11种植物功能型的覆盖度REVEALS估算结果（详细信息请参阅Excel文件内的"Metadata"文件夹）。
在两个Excel文件中，"Metadata"文件夹包含数据文件夹内缩写的说明；"Sitedata"文件夹为用于REVEALS重建的孢粉记录元数据文件；此外共包含10个REVEALS数据/结果文件夹，其中前5个文件夹对应LandClim I项目5个时间窗口的REVEALS估算结果，后5个文件夹则对应上述估算结果的相应标准误（Standard Errors, SEs）。所有REVEALS估算结果及其标准误均以网格单元占比形式呈现（所有REVEALS估算结果的总和为1）。在每个数据/结果文件夹中，LCGRID与LCGRID_ID列为项目内部标识符，"cell"列为网格左上角（西北方向）的坐标，"Cell label"列为带有REVEALS数据/结果的网格单元所属国家编号。在文件LandClim I LCTs.xls中，5个名为"....BPmeanLC"的文件夹对应5个时间窗口下3种土地覆盖型的REVEALS估算结果，5个名为"....BPSE"的文件夹则对应上述土地覆盖型REVEALS估算结果的标准误。在文件LandClim I PFTs.xls中，5个名为"....BPmeanLC"的文件夹对应5个时间窗口下11种植物功能型的REVEALS估算结果，5个名为"....BPSE"的文件夹则对应上述植物功能型REVEALS估算结果的标准误。