台大實驗林神木溪保護林兩相鄰林分枯落物動態與其養分之研究

Litterfall and nutrient dynamics in two adjacent stands in Shenmuhsi Forest Reserve of Experimental Forest, National Taiwan University

朱珮綺(Pei-Chi Chu)

指導教授 ： 鹿兒陽

國立臺灣大學/生物資源暨農學院/森林學研究所/碩士(2005年)

https://doi.org/10.6342/NTU.2005.00897

摘要

本研究以南投縣信義鄉台大實驗林神木溪保護林中相鄰之天然闊葉林與石竹林為調查對象，自2002年6月至2004年5月，每月收集一次枯落物，為期兩年共收集24次。本試驗之主要目的在於瞭解兩林分之枯落物特性與養分回歸情形。結果顯示天然闊葉林第一、二年之年枯\\\落量分別為9,893、14,331 kg ha-1，第二年的枯落物大幅提升，主要是因為收集到較大量的枝條、樹皮與繁殖體；石竹林第一、二年之年枯\\\落量分別為8,757、7,840 kg ha-1，兩年相差較小。枯落物組成中，天然闊葉林以落葉為最主要組成，枝條與樹皮次之，石竹林同樣也是以落葉最多，竹鞘次之。天然闊葉林第一、二年的枯\\\落物高峰分別在7月及9月，均是因為颱風的侵襲而將大量的枝條打落所致；石竹林第1、2年的枯落物高峰則分別在7月及5月，主要是因為新葉發生，老葉大量枯落所致。在年枯\\\落物的養分回歸量方面，大致上均以天然闊葉林較石竹林為高，而枯落物的組成中又以落葉對於養分回歸量之貢獻最大。
在森林地表總乾重方面，天然闊葉林的森林地表乾重量14,341 kg ha-1，高於石竹林的7,666 kg ha-1，主要是因為天然闊葉林有較多的枝條，不過葉部組成則是以石竹林較多。若以各組成所佔年枯落量及枝葉層量之比例來比較推測枯\\\落物的分解速率，兩林分枯落物各組成之分解速率均以葉部的分解較快，枝條部份分解較慢。森林地表的養分含量同樣也是以天然闊葉林為最高，而枝葉層、半分解層與腐殖質層中，又以枝葉層所含養分最高。
綜合上述結果可知即使兩林分位處同一環境中，林分的類型不同，其枯落物的量、組成與養分等均不同，可能會改變養分的循環、造成土壤性質之差異。

關鍵字

神木溪保護林 ； 闊葉林 ； 竹林 ； 枯落物 ； 森林地表 ； 養分回歸

並列摘要

This study compared the litterfall dynamics and nutrient return between natural hardwood forest and its adjacent Thill bamboo (Phyllostachys lithophila) plantation in the Experimental Forest of National Taiwan University. The litterfall was collected once a month for 24 months (June, 2002~May, 2004). The results showed that annual litterfall was 9,893 and 14,331 kg ha-1 in natural hardwood forest in the first and second years, respectively, and 8,757 and 7,840 kg ha-1 in the bamboo plantation. In hardwood forest, the higher amount of litterfall in the second year was largely attributed to the greater quantity of fallen branches, bark, and reproductive organs. In both natural hardwood forest and bamboo plantation the most important component was leaf-fall for both years. The litterfall of natural hardwood forest peaked in July and September in the first and second years, respectively, when branches were blown off by strong wind and heavy rain. In contrast, the litterfall of bamboo plantation peaked in July and May in the first and second years, respectively, when new leaves replaced senescent leaves. The nutrient content of the annual litterfall in natural hardwood forest was higher than that in the bamboo plantation. Compared to the other components, the fallen leaves contributed more to the nutrient content of the annual litterfall in both stands.
The dry weight of the forest floor in natural hardwood forest (14,341 kg ha-1) was greater than that in the bamboo plantation (7,666 kg ha-1) because natural hardwood forest accumulated more fallen branches. The comparisons between the annual litterfall and forest floor suggested that fallen leaves decomposed faster than did fallen branches in both stands. The nutrient content of the forest floor in natural hardwood forest was also higher than that in the bamboo plantation, and of the three layers, litter layer was the highest nutrient content.
These results suggest that even on the same site, the litterfall and its nutrient composition vary with vegetation, and thus may cause changes in nutrient cycling and soil properties.

並列關鍵字

Shenmuhsi Forest Reserve ； hardwood forest ； bamboo plantation ； litterfall ； forest floor ； nutrient return

參考文獻

林光清、洪富文、程煒兒、蔣先覺、張雲翔 1996 福山試驗林土壤調查與分類 台灣林業科學 11(2)：159∼174。

林國銓 1997 福山闊葉林枯落物及枝葉層之動態變化 台灣林業科學 12: 135~144。

陸象豫、漆陞忠、盧惠生 1988 不同林相枯枝落葉層物理及水文特性

doubled the annual litterfall of the Fu-Shan mixed hardwood forest ecosystem in northeastern Taiwan. Bulletin of Taiwan Forestry Research Institute. New Series. 10: 485~491.

崔君至 2000 南仁山區土壤性質在不同地形位置之分佈 台灣大學農業化學研究所 107頁。