七家灣溪濱岸植群之地上部生物量與生產量

Aboveground Biomass and Production of Riparian Vegetation in the Cijiawan Stream

蔡尚惪(Shang-Te Tsai) ； 郭礎嘉(Chu-Chia Kuo) ； 曾喜育(Hsy-Yu Tzeng) ； 曾彥學(Yen-Hsueh Tseng)

《環球科技人文學刊》 12期 (2011/01) Pp. 1-21

https://doi.org/10.29932/JSTHTI.201101.0001

摘要

七家灣溪是櫻花鉤吻鮭的重要棲地，為使其族群得以延續，保護森林溪流生態系乃是當務之急；又為對溪流生態系進行最有效之管理，必須建立其完整的生態系模式，而濱岸植群之地上部生物量與生產量，即為研究濱岸生態系之重要參數。因此，本研究藉由於桃山北溪（#1）、桃山西溪（#2）、一號壩（#4）、繁殖場（#5）、高山溪（#8），以及有勝溪（#9）等6個測站的植群監測調查資料，估算其生物量與淨生產量。結果發現2005年七家灣溪各樣區喬木層的單位面積生物量為22-277ton ha^-1；而2007年各樣區之喬木層生物量皆有所增長，其單位生物量為28-303ton ha^-1。另2005年濕季之地被層生物量為15-53ton ha^-1，2007年地被層生物量較2005年低，2007年濕季之地被層生物量為14-36 ton ha^-1；又位於洪氾區的植群生物量，遠低於其他位於中坡或邊坡的植群生物量，是故若無大規模性的崩塌，則崩塌的干擾影響小於溪水氾濫的干擾。此外，喬木層的淨生產量，以桃山西溪測站（#2）的樣區2最高（33.49ton ha^-1yr^-1），而位於桃山北溪測站（#1）之樣區10的淨生產量最低（2.73ton ha^-1yr^-1）；又其他樣區之淨生產量為6-29ton ha^-1yr^-1；另地被層淨生產量中，2005年以繁殖場測站（#5）的樣區3最高（3.33ton ha^-1month^-1），有勝溪測站（#9）之樣區6最低者（0.41ton ha^-1month^-1）；而2007-2008年地被層的淨生產量略低於2005年，然仍以繁殖場測站（#5）的樣區3最高（1.90ton ha^-1month^-1），而桃山西溪測站（#2）之樣區1最低（0.09ton ha^-1month^-1），此等顯示開闊向陽的濱岸帶，使得地被層植物生長較為迅速。此外，2005年2月至2007年10月止之枯落物收集，其枯落物最主要的輸入來源為葉，各年皆佔70%以上的輸入量，且以臺灣赤楊、臺灣二葉松與栓皮櫟的葉子居多，其次為枝條，約為9-19%的輸入量。

關鍵字

濱岸植群 ； 生物量 ； 淨生產量 ； 枯落物

並列摘要

Cijiawan streams of Wuling area is the important habitat of Formosan landlocked salmon (Oncorhynchus masou formosanus Jordan & Oshima). Riparian vegetation biomass, net production is the important factors for the riparian ecosystem, and these could provide the information for decision making of river ecosystem management. In this study, we estimated the aboveground biomass and net production of vegetation via the monitoring data of riparian vegetation in the six surveying station of Taoshan North Stream (#1), Taoshan West Stream (#2), Dam I (#4), Breeding Center (#5), Gaoshan Stream (#8) and Yousheng Stream (#9) from 2005 to 2008. The results showed the overstory biomass was about 22-277 ton ha^-1 in 2005. The overstory biomass of 2007 was higher than 2005, is about 28-303 ton ha^-1. The understory biomass of 2007 was lower than 2005. The understory biomass of the wet period was about 14-36 ton ha^-1 in 2007, and about 15-53 ton ha^-1 in 2005 of the wet period. The vegetation biomass of flood area was lower than the others of the middle or side slope. It revealed the effect of collapse was lower than the river flooded if without giant rock falling. Besides, the net production of overstory was higher (33.49 ton ha^-1yr^-1) in the plot 2 of the surveying station Taoshan West Stream (#2), and it was lower (2.73 ton ha^-1yr^-1) in the plot 10 of the surveying station Taoshan North Stream (#1). And the others were about 6-29 ton ha^-1yr^-1. In 2005, the net production of understory was higher in the plot 3 (3.33 ton ha^-1month^-1) of the surveying station Breeding Center (#5), and it was lower in the plot 6 (0.41 ton ha^-1month^-1) of the surveying station Yousheng Stream (#9). The net production of 2007-2008 was lower than 2005. The net production of understory was also higher in the plot 3 (1.90 ton ha^-1month^-1) of the surveying station Breeding Center (#5), and it was lower (0.09 ton ha^-1month^-1) in the plot 1 of the surveying station Taoshan West Stream (#2) in 2007-2008. It means the understory growth rapidly in the Broad, shine brightly riparian zone. Otherwise, the total biomass of litter fall was collected from February, 2005 to October, 2007, of which 70% was composed of foliar litter, and 9-19% was branch litter. The foliar litter was composed of Alnus formosana, Pinus taiwanensis, and Quercus variabilis.

並列關鍵字

riparian vegetation ； biomass ； net production ； litter fall