Please use this identifier to cite or link to this item: http://hdl.handle.net/11455/20584
標題: 關刀溪森林生態系干擾地蕨類植被之建立
The establishment of pteridophytic vegetation in the disturbed sites of Guandaushi forest ecosystem
作者: 林志欽
Lin, Jyh-Chin
關鍵字: Guandaushi forest ecosystem;關刀溪森林生態系;pteridophyte;landslide;fire;蕨類植物;崩塌地;野火
出版社: 植物學系
摘要: 
關刀溪森林生態系近年發生的重大干擾包括地震崩塌及火燒。本研究於2001年3月至2002年5月期間在關刀溪森林生態系內之崩塌地及火燒地進行蕨類小苗監測、土壤孢子庫發芽試驗以及未干擾地之蕨類植群調查。在干擾地樣區及其對照樣區調查蕨類小苗,記錄到12科21種1亞種2變種,合計1,143株小苗。土壤孢子庫之調查分別於2001年1月、3月、5月由干擾地樣區及其對照樣區取土,各進行為期一年的土壤孢子庫發芽試驗,土樣在四週後開始出現配子體,六週後出現幼孢子體,共記錄到蕨類15科31種2變種,合計25,552株。在未干擾地之蕨類植群調查到13科22種3變種。
崩塌發生後,空氣中蕨類孢子落於崩塌地上,陽性蕨類孢子如中華白(白科)、芒萁(白科)、烏蕨(陵齒蕨科)、烏毛蕨(烏毛蕨科)萌發為小苗,為崩塌地蕨類建立之先驅物種。崩塌地因土層流失,小苗數量較未崩塌地少,但在有其他草本植物覆蓋的崩塌地則較多,推測地表的穩定度與地表覆蓋物影響崩塌地蕨類小苗之建立。火燒後,巒大蕨與蘇鐵蕨藉由受土壤與鱗片保護的頂芽迅速萌發,恢復族群。干擾地乾燥的地表環境有礙孢子的萌發以及精卵結合過程,推測在干擾地蕨類的建立過程中,水分可能是蕨類有性生殖的限制因子。
土壤孢子庫含有種類與數量皆豐富的孢子,其孢子部分源自周圍蕨類植群散發而來,亦有遠方的蕨類孢子隨氣流之流動而飄來。野火的高溫與崩塌後表土的流失破壞了土壤孢子庫,干擾地之孢子庫密度低於未干擾地。蘇鐵蕨火燒後第一個月著生孢子囊之蕨葉百分比達87%,未火燒樣區則僅5%,受野火刺激所產生的孢子成熟後能在火燒跡地下種萌發,但小苗死亡率偏高。

The recent disturbances at Guandaushi forest ecosystem include earthquake-caused landslides and man-caused fire. The emergence and mortality of pteridophytic sporelings at disturbed sites, the composition and density of the soil spore bank, and the pteridophytic vegetation at undisturbed sites have been monitored in landslided and burned areas from March of 2001 to May of 2002. A total of 1,143 sporelings, belonging to 12 families, 21 species, 1 subspecies and 2 varieties, have been recorded in the studied plots. In soil spore bank, 25,552 sporelings in total, belonging to 15 families, 31 species and 2 varieties, were recorded during germination tests. The gametophytes emerged from the soil sample in four weeks, and sporelings appeared in six weeks. For the pteridophytic vegetation of undisturbed sites, 13 families, 22 species and
3 varieties were recorded.
The shade-intolerant species, Diplopterygium chinensis, Dicranopteris linearis var linearis, Sphenomeris chusan, and Blechnum orientale, were the pioneers at landslide. The density of sporelings were lower at landslide sites because of loss of top soil, but higher at sites that covered with herb. The stability and herb of topsoil will affect the establishment at landslides. After burning, buds of Brainea insignis which covered with dense scales, and buds of Pteridium aquilinum subsp. Wightianum which protected by soil pullulated rapidly. Drought affected spore germination and fertilization of pteridophytes, and soil water content might be the limiting factor during pteridophytic sexual reproduction at disturbed sites.
There were diverse species and abundant spores stored in soil spore bank. Part of the spores in the soil came from surrounding vegetation, and part of them from remote vegetation. Heat of fire and loss of top soil in landslides resulted in the lower density of spore bank in disturbed sites comparing to that of undisturbed sites. After burning, the percentage of Brainea insignis frond that product sorus was 87% in first month at burned sites, and only 5% at unburned sites. Spores could germinate at burned site, but mortality was high.
URI: http://hdl.handle.net/11455/20584
Appears in Collections:生命科學系所

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