Global forest reference set with time series annual change information

<p><strong>Brief introduction of the reference&nbsp;set:</strong></p> <ul> <li>The initial sample points were stratified. The ratio of non-forest, forest and forest change&nbsp;stratum&nbsp;area is about 67:27:6. In order to increase the number of forest and forest change sample points, the ration of forest sample, forest change sample and non-forest sample points is roughly 4:1:1. The information of stratum identifier is provided in this sample set.&nbsp;&nbsp;The study generated 12925 initial sample points which were further reduced to 10339 points (6252 persisting forest sample points, 2049 change sample points and 2038 persisting non-forest sample points). The details are shown in Table 1.&nbsp;</li> </ul> <table> <caption>Table 1. Initial and finial sample size in each stratum</caption> <tbody> <tr> <td><strong>Stratum name</strong></td> <td><strong>Percent area of each stratum</strong></td> <td><strong>Initial sample size</strong></td> <td><strong>Final sample size</strong></td> <td><strong>Eliminated sample size</strong></td> </tr> <tr> <td>Forest</td> <td>27%</td> <td>8332</td> <td>6252</td> <td>1644</td> </tr> <tr> <td>Non-forest</td> <td>67%</td> <td>1892</td> <td>2038</td> <td>207</td> </tr> <tr> <td>Forest change</td> <td>6%</td> <td>2701</td> <td>2049</td> <td>735</td> </tr> <tr> <td>Sum</td> <td>100%</td> <td>12925</td> <td>10339</td> <td>2586</td> </tr> </tbody> </table> <p>&nbsp;</p> <ul> <li>The sample set will be provided in shapefile version. (The eliminated sample points will not be provided.) In this version, the provided attributions are shown in Table 2.</li> </ul> <p>&nbsp;</p> <table> <caption>Table 2. Details of provided attributions in this version</caption> <tbody> <tr> <td><strong>Name</strong></td> <td><strong>Description</strong></td> </tr> <tr> <td>per_f</td> <td>unchanged forest&nbsp; &nbsp; &nbsp; &nbsp; &nbsp;(0: No&nbsp; &nbsp; 1: Yes)</td> </tr> <tr> <td>per_nonf</td> <td>unchanged non-forest&nbsp; (0: No&nbsp; &nbsp; 1: Yes)</td> </tr> <tr> <td>change</td> <td>forest change&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;(0: No&nbsp; &nbsp; 1: Yes)</td> </tr> <tr> <td>loss</td> <td>forest loss times</td> </tr> <tr> <td>gain</td> <td>forest gain times</td> </tr> <tr> <td>times</td> <td>change times (gain + loss)</td> </tr> <tr> <td>changeinfo</td> <td>year and order of change</td> </tr> <tr> <td>initial_s</td> <td>initial stratum identifier:&nbsp;change/perf (persisting forest)/nonf (persisting non-forest)</td> </tr> </tbody> </table> <p>&nbsp;</p> <ul> <li>This reference&nbsp;set will be updated regularly. Now it&#39;s version 1.1 (from 2000 to 2020).</li> </ul> <p>&nbsp;</p> <p><strong>NOTES:</strong></p> <ol> <li>Please be cautious while using the sample points with multiple change times.&nbsp;</li> <li>We encourage people to send us feedback if you found some mistakes while using this sample set via email.</li> <li>Welcome discussions around potential collaborations. 【You can email&nbsp;Jing (guoj15@tsinghua.org.cn).】</li> </ol> <p>&nbsp;</p> <p><strong>Citation:</strong></p> <p>Please cite the dataset including the version number and the following paper when using this data:&nbsp;</p> <p>Jing Guo, Zhiliang Zhu &amp; Peng Gong&nbsp;(2022)&nbsp;A global forest reference set with time series annual change information from 2000 to 2020,&nbsp;International Journal of Remote Sensing,&nbsp;43:9,&nbsp;3152-3162,&nbsp;DOI:&nbsp;<a href="https://doi.org/10.1080/01431161.2022.2088256">10.1080/01431161.2022.2088256</a></p>