Google Earth Engine ——Landsat Vegetation Continuous Fields (VCF) 樹木覆寫層包含高度超過 5 米的木本植被覆寫資料集

GLCF: Landsat Tree Cover Continuous Fields

The Landsat Vegetation Continuous Fields (VCF) tree cover layers contain estimates of the percentage of horizontal ground in each 30-m pixel covered by woody vegetation greater than 5 meters in height. The data represent three nominal epochs, 2000, 2005 and 2010, compiled from the NASA/USGS Global Land Survey (GLS) collection of Landsat data. The product is derived from all seven bands of Landsat-5 Thematic Mapper (TM) and/or Landsat-7 Enhanced Thematic Mapper Plus (ETM+), depending on the GLS image selection.

Tree cover, the proportional, vertically projected area of vegetation (including leaves, stems, branches, etc.) of woody plants above a given height, affects terrestrial energy and water exchanges, photosynthesis and transpiration, net primary production, and carbon and nutrient fluxes. Tree cover also affects habitat quality and movements of wildlife, residential property value for humans, and other ecosystem services. The continuous classification scheme of the VCF product enables better depiction of land cover gradients than traditional discrete classification schemes. Importantly for detection and monitoring of forest changes (e.g., deforestation and degradation), tree cover provides a measurable attribute upon which to define forest cover and its changes. Changes in tree cover over time can be used to monitor and retrieve site-specific histories of forest change.

The dataset has been produced for three year epochs: 2000, 2005, 2010, with an image in the collection for each available WRS2 path/row.

Landsat Vegetation Continuous Fields (VCF) 樹木覆寫層包含高度超過 5 米的木本植被覆寫的每個 30 米像素中水準地面百分比的估計值。資料代表三個名義時期，2000 年、2005 年和 2010 年，由 NASA/USGS 全球土地調查 (GLS) 收集的 Landsat 資料彙編而成。該産品源自 Landsat-5 專題地圖繪制器 (TM) 和/或 Landsat-7 增強專題地圖繪制器 Plus (ETM+) 的所有七個波段，具體取決于 GLS 圖像選擇。

樹木覆寫率，即高于給定高度的木本植物的植被（包括葉、莖、枝等）的比例、垂直投影面積，影響陸地能量和水分交換、光合作用和蒸騰作用、淨初級生産以及碳和養分通量.樹木覆寫還影響野生動物的栖息地品質和活動、人類住宅财産價值以及其他生态系統服務。 VCF 産品的連續分類方案比傳統的離散分類方案能夠更好地描述土地覆寫梯度。對于檢測和監測森林變化（例如，森林砍伐和退化）很重要，樹木覆寫率提供了一個可衡量的屬性，用于定義森林覆寫率及其變化。樹木覆寫率随時間的變化可用于監測和檢索特定地點的森林變化曆史。

該資料集已經生成了三年的時期：2000、2005、2010，每個可用的 WRS2 路徑/行在集合中都有一個圖像。

Dataset Availability

2000-01-01T00:00:00 - 2010-12-31T00:00:00

Dataset Provider

NASA LP DAAC at the USGS EROS Center

Collection Snippet

ee.ImageCollection("GLCF/GLS_TCC")

Resolution

30 meters

Bands Table

Name	Description	Min	Max	Units
tree_canopy_cover	The percentage of pixel area covered by trees.	100	%
uncertainty	RMSE for tree-canopy_cover
source_index	Identity of source image used for the particular pixel. This is an index into the per image metadata array 'sources'.

影像屬性：

Name	Type	Description
path	Double	Path
pathrow	String	Path and row
row	Double	Row
sources	Double	Sources
tree_canopy_cover_class_palette	Double	Tree canopy cover class palette
tree_canopy_cover_class_values	Double	Tree canopy cover class values
year	Double	Year

代碼：

var dataset = ee.ImageCollection('GLCF/GLS_TCC')
                  .filter(ee.Filter.date('2010-01-01', '2010-12-31'));
var treeCanopyCover = dataset.select('tree_canopy_cover');
var treeCanopyCoverVis = {
  min: 0.0,
  max: 100.0,
  palette: ['ffffff', 'afce56', '5f9c00', '0e6a00', '003800'],
};
Map.setCenter(-88.6, 26.4, 3);
Map.addLayer(treeCanopyCover, treeCanopyCoverVis, 'Tree Canopy Cover');
           

資料引用：

Data citation: Tree Canopy Cover, {Year, ...}, Global Land Cover Facility, www.landcover.org.

Paper/Methods Citation: Sexton, J. O., Song, X.-P., Feng, M., Noojipady, P., Anand, A., Huang, C., Kim, D.-H., Collins, K.M., Channan, S., DiMiceli, C., Townshend, J.R.G. (2013). Global, 30-m resolution continuous fields of tree cover: Landsat-based rescaling of MODIS Vegetation Continuous Fields with lidar-based estimates of error. International Journal of Digital Earth, 130321031236007. doi:10.1080/17538947.2013.786146.