Method Analysis for Collecting and Processing in-situ Hyperspectral Needle Reflectance Data for Monitoring Norway Spruce

Forest damage induced by bark beetle can cause major economic losses in forest- . Hyperspectral remote sensing data and state of art very high spatial resolution satellite data of- a great potential for assessing tree vitality. How- , a better understanding of the effects of vitality and its impact on the spectral behaviour of is needed. Filling this knowledge gap can a significant contribution to improve the in- of remote sensing data. However, it is unclear which method for needle spectra col- is most suitable. In this work, two methods spectral reflectance measurements of Norway needles using portable spectroradiometers tested and analysed: using a classical fore op- and a so-called contact probe. The spectral re- data were evaluated with different statis- similarity measure techniques. Besides ana- the measurements themselves, the methods compared in terms of their practicality. Fur- , the impact of storage on the reflection was investigated. The spectral measure- were performed in the field as well as in a and repeated three times during the 2013 growing season. Based on the obtained results recommend measuring needle samples with the probe of portable spectroradiometers.