無人空中載具數位影像應用於林分蓄積量之推估

Estimating Stand Stocks by Unmanned Aerial Vehicle Image

朱宗威(Tsung-Wei Chu) ； 陳建璋(Jan-Chang Chen) ； 陳朝圳(Chaur-Tzuhn Chen)

《國立臺灣大學生物資源暨農學院實驗林研究報告》 28卷1期 (2014/03) Pp. 45-54

https://doi.org/10.6542/EFNTU.201403_28(1).0004

摘要

本研究以屏東縣台糖人工林的桃花心木、光臘樹、臺灣櫸為研究對象，利用無人空中載具（Unmanned Aerial Vehicle, UAV）所拍攝的高解析力數位影像與樣區現地資料作為材料，從UAV航空照片中萃取林分性態值，建立其立木材積式及空中材積式。研究結果顯示出運用UAV航照進行林分性態值萃取，將樹種所測得林分性態值與現地樣區量測資料進行迴歸分析，桃花心木樹冠幅之決定係數（R^2）為0.9、樹高之決定係數（R^2）為0.97；光臘樹樹冠幅之（R^2）為0.79、樹高之（R^2）為0.85，臺灣櫸樹冠幅之決定係數（R^2）為0.63、樹高之決定係數（R^2）為0.79。以UAV影像所萃取之樹冠鬱閉度及樹高為變數，所建立之各樹種空中材積式其決定係數R^2分別為，桃花心木為0.70、光臘樹為0.71，臺灣櫸為0.50。本研究所得之結果將可證明運用高解析力數位影像對於林分蓄積量具高準確度。

關鍵字

無人空中載具 ； 林分性態值 ； 林分蓄積量

並列摘要

In this study, Swietenia macropnylla King, Zelkova serrate (Thunb.) Makino, and Fraxinus griffithii Hayata are selected as research subjects and Taiwan Sugar plantation, Pingtung County, is the study site. Unmanned Aerial Vehicle (UAV) image and field sampling data are the research materials. This study used UAV's high resolution images to extract the stand characteristics and establish the volume formula and aerial volume formula of standing timber. Regression analysis was used to investigate the relationship between image and surveying data of stand characteristics. The results show that tree crown and tree height can directly extract from UAV aerial image; the crown coefficients of determination (R^2) are 0.90 (Swietenia macropnylla ), 0.79 (Fraxinus griffithii ) and 0.63 (Zelkova serrate ); and the coefficients of determination of tree height are 0.97 (Swietenia macropnylla ), 0.85 (Fraxinus griffithii ) and 0.79 (Zelkova serrata ). Additionally, the aerial stand volume table had been established with independent variables of crown closure and tree height extracting from UAV image that shows the volume coefficients of determination (R^2) are 0.70 (Swietenia macropnylla ), 0.71 (Fraxinus griffithii ) and 0.50 (Zelkova serrate ). This study proves that the high resolution digital images have high accuracy for estimating stand volume.

並列關鍵字

Unmanned Aerial Vehicle ； Stand Characteristics ； Stand Volume