A Study of Ips Typographus Pest Infestation with the use of Multiangular CHRIS-PROBA Data
Filchev, Lachezar1; Panayotov, Momchil2; Ling, Feilong3
1Space Research and Technology Institute at the Bulgarian Academy of Sciences (SRTI-BAS), BULGARIA; 2University of Forestry, Dendrology Department, BULGARIA; 3Spatial Information Research Center, Fuzhou University, CHINA
Insects' infestations of coniferous forests have been in the focus of the forestry community for decades. Research that is dealing with the assessment of the impacts on forests and assessment of the area affected by the infestations has been assisted by remotely sensed data after the onset of civilian remote sensing era and making the large archives of satellite data centres of NASA, ESA, and JAXA available to the researcher's community. The present study assesses the impact from Ips typographus outbreak on Picea abies forests in the UNESCO MAB biosphere reserve "Bistrishko branishte" in Bulgaria using multiangular CHRIS spectroradiometer data from the ESA third-party mission PROBA. The study aims at assessing the impact of the infestation by comparing the multi-angular NDVI and narrow band vegetation indices derived from CHRIS data to field biometrical data: DBH, age, volume etc. To study the different effects of the forest structure on the spectral reflectance characteristics, the forest is subdivided to elementary landscapes. After that statistics from the satellite data is drawn from the elementary landscapes and compared with the field data. As a result it is found that the landscape units affected by pest infestation can be well differentiated on CHRIS PROBA data. The results from the study suggest that continuous field and space monitoring of insect infested coniferous forests has to be carried out by employing more biophysical parameters. This is needed in order to better link the field and space borne data and to provide timely and accurate assessment of areas affected by the infestation.