台北五股與台南龍崎綠竹林之林分結構與生物量

The stand structure and biomass of Bambusa oldhami plantations in Wugu, New Taipei and Longqi, Tainan.

本試驗調查台北五股與台南龍崎地區綠竹（Bambusa oldhami）林分之生長及生物量。綠竹林分生長分布特性方面，五股樣區之林分株數頻度以胸徑3 ~ 4 cm者佔最多，龍崎樣區則多分佈於5 ~ 6 cm；五股樣區之竹叢數及竹稈數分別為每公頃766 ± 153叢（clumps ha-1）、4,800 ± 1,708稈（culms ha-1），竹叢數和龍崎樣區（每公頃700 ± 100叢）無顯著差異，但竹稈數低於龍崎樣區之10,766 ± 1,159稈（culms ha-1）；五股樣區之竹叢稈數為6 ± 2稈（culms clump-1）較龍崎樣區16 ± 8稈（culms clump-1）少；林分生長性狀方面，兩試驗地之平均胸徑，五股與龍崎樣區分別為3.3 ± 0.5 cm、4.3 ± 1.1 cm；而五股樣區之平均竹高為11.8 ± 0.3 m，龍崎地區則為11.7 ± 0.3 m。地上部乾重方面，五股樣區因竹稈數低且竹叢稈數較數少，其地上部林分總生物量亦遠低於龍崎樣區；五股與龍崎樣區之總生物量乾重分別為15.6 ± 5.7 ton ha-1、54.5 ± 4.2 ton ha-1；其中五股及龍崎樣區各齡級之生長及生物量結果，1、2年生之總生物量無顯著差別，而龍崎樣區3年生竹齡之總生物量較低，顯示其與綠竹之經營栽培管理方式有關，五股筍農傾向將3年生以上之老竹伐除。 This study investigated the plantations of green bamboo (Bambusa oldhami) in Wugu, New Taipei and Longqi, Tainan. Results show that, the frequency of bamboo culms in both sites are the highest at 3~ 4 cm DBH class in Wugu, and at 5~ 6 cm DBH class in Longqi. The number of clumps and culms are 766 ± 153 clumps ha-1 and 4,800 ± 1,708 culms ha-1 in Wugu, and 700 ± 100 clumps ha-1 and 10,766 ± 1,159culms ha-1 in Longqi, respectively. The number of culms at 6 ± 2 culms clump-1 in Wugu is lower than the number of culms at 16 ± 8 culms clump-1 in Longqi. Following this, the average of diameter is significant different between two experimental sites. There are 3.3 ± 0.5 cm and 4.3 ± 1.1 cm respectively in the plantations of Wugu and Longqi. The average height of 11.8 ± 0.3 m in Wugu is the same as 11.7 ± 0.3 m in Longqi. Because of the amount of culms and clumps in the plantations of Wugu is lower, the aboveground biomass is lower than Longqi. The aboveground biomass in Wugu and Longqi are 15.6 ± 5.7 ton ha-1 and 54.5 ± 4.2 ton ha-1, respectively. The aboveground biomass at different ages are not significant differences between age 1 and age 2 in Wugu and in Longqi, but significant low at age 3 in Longqi only. The results indicate that Wugu's bamboo farmers prefer to cut down old bamboos which over age 3.