Arnt Kristian Gjertsen

Forsker

(+47) 473 12 431
arnt.kristian.gjertsen@nibio.no

Sted
Ås - Bygg O43

Besøksadresse
Oluf Thesens vei 43, 1433 Ås (Varelevering: Elizabeth Stephansens vei 23)

Til dokument

Sammendrag

JordbrukSat er et nasjonalt vektorkart som viser den geografiske fordelingen av ulike veksttyper på jordbruksareal, samt jordbruksareal som er nedbygd. Kartet framstilles fra satellittbilder og offentlig kartdata med bruk av maskinlæring og deler jordbruksarealet i seks klasser.

Sammendrag

The national forest authority monitors forest regeneration on clear-cut areas annually and needs a more objective and unbiased sample. This can be solved with satellite images, and a method to detect new clear-cuts with time series of Sentinel-2 satellite images has been developed and tested. The 25 % percentile of the Normalized Burn Ratio (NBR) index, based on near-infrared and short wave infrared bands, is calculated and the differential (dNBR) between two years is used to detect new forest clearings. The method has been tested against a management plan with new clear-cuts in 2017. A total of 162 points, 81 in clear-cut and 81 in other stands, was used to test the accuracy. Based on the confusion matrix, the F1 score was 0.97 and the more balanced Matthews correlation coefficient 0.95.