Hyperspectral Image Analysis for Wear Stress Diagnosing of Zoysiagrass

Jae-Gyeong  Jung1   Jun-Hyuck  Yoon1   Eon-Ju  Jin1   Kwon-Seok  Jeon1   Young-Sun  Kim2,3   Eun-Ji  Bae 1,*   

1Forest Biomaterials Research Center, National Institute of Forest Science, Jinju 52817, Korea
2Division of Life & Environmental Science, College of Natural and Life Sciences, Daegu University, Gyeongsan 38453, Korea
3Institute of Basic Science, Daegu University, Gyeongsan 38453, Korea


The objective of this study was to diagnose the wear stress of zoysiagrass (Zoysia spp.) based on visible/near-infrared (VIS/NIR) hyperspectral image and vegetation index. As a result of comparing the reflectance measured from the leaves, both zoysiagrasses (Zoysia japonica and Z. matrella) showed a slight increase in reflectance at 550 nm after the wear stress, that the greenness decreased after wear stress. Considering that the reflectance of 600~700 nm, which is the red wavelength band was greatly increased, it was found that leaf chlorosis and leaf aging occurred in both zoysiagrasses due to wear stress. The NIR reflectance decreased overall, indicating that the occurrence of stress caused by the wear can be diagnosed. When comparing the vegetation index before and after wear stress, the normalized difference vegetation index (NDVI) and RENDVI (Red edge NDVI) of Z. japonica decreased by 36.5% and 43.0%, and NDVI and RENDVI decreased by 35.3% and 37.9% of Z. matrella. Also, through the evaluation of vegetation images through NDVI, it was found that the turfgrass health was significantly reduced before and after wear condition. EVI decreased by 33.4% in Z. japonica and 46.1% in Z. matrella, which was effective in Z. matrella. PSSRa, b, c decreased by 63.0%, 56.9%, and 45.6% in Z. japonica and by 65.7%, 58.9%, and 39.5% in Z. matrella. With this hyperspectral analysis, it was possible to confirm the change in reflectivity that varies depending on the wear conditions between Z. japonica and Z. matrella, and it was confirmed that the damage and stress of the wear could be quantified through the vegetation index.

Figures & Tables

Fig. 1.A motor-driven equipment used for wear stress treatment in this study.