Global forest reference set with time series annual change information

Brief introduction of the reference set:

The initial sample points were stratified. The ratio of non-forest, forest and forest change stratum 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.  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. 

Table 1. Initial and finial sample size in each stratum

Stratum name
Percent area of each stratum
Initial sample size
Final sample size
Eliminated sample size

Forest
27%
8332
6252
1644

Non-forest
67%
1892
2038
207

Forest change
6%
2701
2049
735

Sum
100%
12925
10339
2586

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.

Table 2. Details of provided attributions in this version

Name
Description

per_f
unchanged forest         (0: No    1: Yes)

per_nonf
unchanged non-forest  (0: No    1: Yes)

change
forest change               (0: No    1: Yes)

loss
forest loss times

gain
forest gain times

times
change times (gain + loss)

changeinfo
year and order of change

initial_s
initial stratum identifier: change/perf (persisting forest)/nonf (persisting non-forest)

This reference set will be updated regularly. Now it's version 1.1 (from 2000 to 2020).

NOTES:

Please be cautious while using the sample points with multiple change times. 

We encourage people to send us feedback if you found some mistakes while using this sample set via email.

Welcome discussions around potential collaborations. 【You can email Jing ([e-mail]).】

Citation:

Please cite the dataset including the version number and the following paper when using this data: 

Jing Guo, Zhiliang Zhu & Peng Gong (2022) A global forest reference set with time series annual change information from 2000 to 2020, International Journal of Remote Sensing, 43:9, 3152-3162, DOI: 10.1080/01431161.2022.2088256