ndvi_to_sem

Convert ndvi raster data into semantic vegetation areas

Access and analyze multi-band greenspace seasonality data cubes
(available for 1,028 major global cities), global Normalized Difference
Vegetation Index / land cover data from the European Space Agency
WorldCover 10m Dataset, and Sentinel-2-l2a images. Users can download data
using bounding boxes, city names, and filter by year or seasonal time window.
The package also supports calculating human exposure to greenspace using a
population-weighted greenspace exposure model introduced by
Chen et al. (2022) <doi:10.1038/s41467-022-32258-4> based on Global Human
Settlement Layer population data, and calculating a set of greenspace
morphology metrics at patch and landscape levels.

Xiaohao Yang

greenSD

Access and Analyze Global GreenSpace Spatial Data

ndvi_to_sem function

<dl><dt>r</dt>
<dd>A SpatRaster with single greenspace layer, typically
the output from <code>get_esa_wc()</code>, or <code>get_s2a_ndvi()</code>.</dd>
<dt>threshold</dt>
<dd>numeric vector of two. Thresholds, defaulting to <code>c(0.2, 0.5)</code>,
for classify two types of vegetation areas according to Hashim et al. (2019):
(1) Non-vegetation (Development and bare land): NDVI values generally below <code>0.2</code>.
(2) Low vegetation (Shrub and grassland): NDVI values generally between <code>0.2</code> and <code>0.5</code>.
(2) High vegetation (Temperate and Tropical urban forest ): NDVI values generally
between <code>0.5</code> and <code>1.0</code>.</dd>
<dt>quiet</dt>
<dd>logical. Whether show progress bars for some process.</dd></dl>

Arguments

ndvi_to_sem — ndvi_to_sem

<dl>

<dt>r</dt>
<dd>A SpatRaster with single greenspace layer, typically
the output from <code>get_esa_wc()</code>, or <code>get_s2a_ndvi()</code>.</dd>


<dt>threshold</dt>
<dd>numeric vector of two. Thresholds, defaulting to <code>c(0.2, 0.5)</code>,
for classify two types of vegetation areas according to Hashim et al. (2019):
(1) Non-vegetation (Development and bare land): NDVI values generally below <code>0.2</code>.
(2) Low vegetation (Shrub and grassland): NDVI values generally between <code>0.2</code> and <code>0.5</code>.
(2) High vegetation (Temperate and Tropical urban forest ): NDVI values generally
between <code>0.5</code> and <code>1.0</code>.</dd>


<dt>quiet</dt>
<dd>logical. Whether show progress bars for some process.</dd>

</dl>

ndvi_to_sem: ndvi_to_sem

Description

Usage

Value

Arguments

References

Examples