屏東平地造林地二氧化碳通量塔樣區地上部累積量與遙測資料相關性研究之初探

Preliminary Study of the Relationships between Aboveground Storage and Remotely Sensed Data at Pingdong Afforestation Land

衛強(Chiang Wei) ； 陳鏡明(Jing-Ming Chen) ； 余瑞珠(Jui-Chu Yu) ； 鄭景鵬(Ching-Peng Cheng) ； 賴彥任(Yen-Jen Lai) ； 洪志遠(Chih-Yuan Hong) ； 江博能(Po-Neng Chiang) ； 張振生(Cheng-Sheng Chang) ； 魏聰輝(Tsong-Huei Wey) ； 蔡明哲(Ming-Jer Tsai) ； 王亞男(Ya-Nan Wang)

《國立臺灣大學生物資源暨農學院實驗林研究報告》 26卷3期 (2012/09) Pp. 175-189

https://doi.org/10.6542/EFNTU.201209_26(3).0002

摘要

森林生態系二氧化碳之碳吸存為地表陸域圈陸氣環交換之重要一環，其中對於生態系生產力關鍵因子之葉面積指數（Leaf Area Index, LAI）及與植生指標（Vegetation Index, VI），在過去數十年已有許多相關研究及廣泛之應用，然而對於亞熱帶森林生態系之著墨較少。本研究對在屏東原臺糖公司萬隆農場平地造林區國立臺灣大學實驗林管理處設立二氧化碳通量觀測塔樣區中8年至9年生14個樹種之地上部蓄積量（Aboveground storage），與利用法國SPOT衛星影像所求得之波段比值（Band Ratio, BR）、波段比平方根（Square Root of Band Ratio, SRBR）、波段差值（Band Difference, BD）、常態化差異植生指數（Normalized Difference Vegetation Index, NDVI）、轉換常態化差異植生指數（Transformed Normalized Difference Vegetation Index, TNDVI）五種植生指數、現場量測之LAI研究三者間之相關性與空間分佈。初步研究成果顯示本區地上部蓄積量為14.19 ± 9.19 m^3 ha^(-1)，與五種植生指標在樣區之其相關係數分别為0.331（p = 0.211），0.317（p = 0.232），0.310（p = 0.244），0.714（p = 0.002）及 0.706（p = 0.002），其中以NDVI之0.714為最佳。使用魚眼鏡頭及TRAC（Tracing Radiation and Architecture of Canopies）葉面積指數儀測得之LAI值分別為0.76 ± 0.37及3.89 ± 2.81，兩者因測定方法不同結果差異較大。另以TRAC儀器量測之聚集指數（Clumping Index, CI）為0.83 ± 0.09，與LAI其樣區內其相關係數則高達0.868（p ＜ 0.001）。初步研究成果顯示以地面調查結合遙測資料來建立平地造林幼齡林之地上部蓄積量與相關性是可行的，惟樣區有明顯生長季與非生長季之區別及部份樣區內有不同樹種混生情形，地上部蓄積量與NDVI、LAI及CI之相關性宜持續觀測並依季節與不同樹種分別建立。

關鍵字

地上部蓄積量 ； 葉面積指數 ； 聚集指數 ； 植生指標 ； 平地造林 ； 遙測資料

並列摘要

The sequestration of carbon dioxide of forest ecosystem plays a crucial role in the terrestrial land-atmosphere interaction. The relationships among leaf area index (LAI), key parameter for modeling the ecosystem productivity and vegetation index from remotely sensed data have been reported and widely used over the past decades. However, few studies of this research theme have been found in subtropical zone. To this end, this research aims to analyze the relationships among LAI and five vegetation index (BR, SRBR, BD, NDVI and TNDVI) from remotely sensed images, in situ measurements and aboveground storage for 9-10yr old plain afforestation (14 species) located at Wanlong farm which is a subtropical region in southern Taiwan and governed by Taiwan Sugar Corporation. The preliminary results show the aboveground storage is 14.19 ± 9.19 m^3 ha^(-1), and the correlation coefficient between aboveground storage and BR, SRBR, BD, NDVI and TNDVI is 0.331 (p = 0.211), 0.317 (p = 0.232), 0.310 (p = 0.244), 0.714 (p = 0.002) and 0.706 (p = 0.002) respectively. The NDVI index performs the best correlation. LAI value using Fisheye or Tracing Radiation and Architecture of Canopies (TRAC) is 0.76 ± 0.37 and 3.89 ± 2.81, respectively. Besides, Clumping Index measured by TRAC is 0.83 ± 0.09 and the correlation coefficient of LAI is 0.868 (p ＜ 0.001). It shows feasibility to estimate aboveground storage using ground investigation and remotely sensed data for young plain afforestation stand. Due to the mixed-plantation and difference between growing and non-growing season in the sample site, the relationship among aboveground storage, LAI and VI is yet to be developed for independent species and may need to modify due to seasonally and inter-annually variation.

並列關鍵字

aboveground storage ； leaf area index (LAI) ； clumping index (CI) vegetation index ； plain afforestation land ； remotely sensed data