Data for geodiv vignette

Data for the vignette associated with the geodiv R package. Data may be used to analyze patterns in landscape heterogeneity over Oregon, USA. Data included are as follows: (var)_img_450m.tif: texture images (gradient metric applied over moving windows), for the specified metric, applied over a small portion of southwestern Oregon state. The window size used is 450x450m. oregon_elevation_SRTM_2000.tif: Shuttle Radar Topography Mission (SRTM) elevation data covering Oregon state for the year 2000. Data were prepared and downloaded in Google Earth Engine in Fall 2019, and are at 30m resolution. oregon_max_growing_season_EVI_2000_2019.tif: Mean maximum growing season MODIS Enhanced Vegetation Index (EVI) data from 2000-2019. Data were prepared and exported from Google Earth Engine in Fall 2019, and are at 250m resolution. elevation_variables.csv: All gradient surface metrics included in the geodiv R package, calculated for 30km moving windows over Oregon state, using a raster of SRTM elevation (above) aggregated to ~2km resolution. evi_variables.csv: All gradient surface metrics included in the geodiv R package, calculated for 30km moving windows over Oregon state, using a raster of MODIS EVI (above) aggregated to 2km resolution.本数据集为配套geodiv R软件包的vignette（R包辅助文档）所用数据，可用于分析美国俄勒冈州的景观异质性格局。所包含的数据如下： 1. (var)_img_450m.tif：针对特定指标，以美国俄勒冈州西南部小片区域为研究范围，通过移动窗口计算得到的纹理影像（基于梯度度量方法），所用移动窗口尺寸为450×450米。 2. oregon_elevation_SRTM_2000.tif：2000年获取的覆盖俄勒冈州全域的航天飞机雷达地形测绘任务（Shuttle Radar Topography Mission, SRTM）高程数据。该数据于2019年秋季在Google Earth Engine中完成处理与下载，空间分辨率为30米。 3. oregon_max_growing_season_EVI_2000_2019.tif：2000-2019年的MODIS增强型植被指数（Enhanced Vegetation Index, EVI）生长季峰值均值数据。该数据于2019年秋季在Google Earth Engine中完成处理与导出，空间分辨率为250米。 4. elevation_variables.csv：包含geodiv R软件包中全部梯度表面度量指标，基于前文提及的SRTM高程栅格（聚合至约2千米分辨率），在俄勒冈州全域以30千米移动窗口计算得到。 5. evi_variables.csv：包含geodiv R软件包中全部梯度表面度量指标，基于前文提及的MODIS EVI栅格（聚合至2千米分辨率），在俄勒冈州全域以30千米移动窗口计算得到。