Assessing land surface phenology in Araucaria-Nothofagus forests in Chile with Landsat 8/Sentinel-2 time series - Data and Material

This dataset contains the Enhanced Vegetation Index (EVI) data used in our research work about land surface phenology of Andean Araucaria-Nothofagus forests as well as the phenology information derived from it. Study area: Conguillío National Park, Chile<br> Study period: 2016-2020 Description of datasets: conguillio.sen2.lnd8.evi.2016.2020.nc - A raster dataset (NetCDF) of EVI values (resolution 10m). EVI was calculated from Level-2 Sentinel-2 and Landsat 8 data. To ensure harmonization, the Landsat 8 data was resampled and reprojected to Sentinel-2 properties prior to the index calculation. evi_gb_beck_white.tif - A raster dataset (GeoTiff) of phenological metrics per year (resolution 10m). Metrics were derived by fitting a double logistic function (see Beck et al., 2006) to the smoothed and interpolated EVI pixel time series. Subsequently, the main phenological variables SOS (start of season) and EOS (end of season) were extracted using a 50% threshold value. The dataset itself is a result of the R package "greenbrown" and the layers are named accordingly (see https://greenbrown.r-forge.r-project.org/phenology.php). It is available as GeoTIFF and as R rasterfile. Details about the methodology and results describing this dataset can be found in the following publication:<br> Kosczor, E., Forkel, M., Hernández, J., Kinalczyk, D., Pirotti, F. &amp; Kutchartt, E., 2022. Assessing land surface phenology in Araucaria-Nothofagus forests in Chile with Landsat 8/Sentinel-2 time series. Int. J. Appl. Earth Obs. Geoinf. 112, 102862. https://doi.org/10.1016/j.jag.2022.102862本数据集包含了我们针对安第斯南洋杉-假山毛榉林（Andean Araucaria-Nothofagus forests）地表物候研究所使用的增强型植被指数（Enhanced Vegetation Index, EVI）数据，以及由此衍生的物候信息。研究区域为智利孔吉利奥国家公园（Conguillío National Park），研究时段为2016年至2020年。 数据集详情如下： 1. conguillio.sen2.lnd8.evi.2016.2020.nc：该数据集为NetCDF格式栅格文件，存储分辨率为10米的EVI数值。EVI指数由二级哨兵2号（Sentinel-2）与陆地卫星8号（Landsat 8）数据计算得到。为保障数据一致性，在计算指数前，已将陆地卫星8号数据重采样并重投影至哨兵2号的坐标系与分辨率参数。 2. evi_gb_beck_white.tif：该数据集为GeoTIFF格式栅格文件，存储分辨率为10米的逐年物候指标。物候指标通过对平滑插值后的EVI像素时间序列拟合双逻辑斯蒂函数（详见Beck等，2006年）得到。随后，采用50%阈值法提取核心物候变量：生长季始期（Start of Season, SOS）与生长季末期（End of Season, EOS）。本数据集由R语言包"greenbrown"生成，各图层命名遵循该包的规范（详见https://greenbrown.r-forge.r-project.org/phenology.php），可获取为GeoTIFF格式与R栅格文件格式。 有关本数据集的方法学细节与研究结果，可参阅以下发表文献： Kosczor, E., Forkel, M., Hernández, J., Kinalczyk, D., Pirotti, F. 与Kutchartt, E., 2022. 利用陆地卫星8号/哨兵2号时间序列评估智利南洋杉-假山毛榉林的地表物候. 国际应用地球观测与地球信息学报（Int. J. Appl. Earth Obs. Geoinf.）, 112卷, 102862号. https://doi.org/10.1016/j.jag.2022.102862