台灣二葉松松針接種不同真菌對其分解 之影響

Abstract

本試驗探討台灣二葉松(Pinus taiwaniensis)松針接種不同真菌對其分解之影響，以減緩林地枝葉層火災燃料的過度累積。其分別接種14種由現址分離之大型真菌與松針內部與表面分離之子囊菌(2種)、不完全菌類(2種)，於室內進行分解試驗。同時，將接種分離自松針內部與表面之菌種，以分解袋方式，施放於大甲溪事業區23林班林地枝葉層進行野外試驗。 各試驗中，分解0-2個月之松針分解速率最大。松針各主要成分留存率，以室內分解較野外分解情形佳，顯示菌種在適當條件下具有潛在的分解能力。不同菌種間對於松針醇苯抽出物與木質素的降解能力亦有所不同。醇苯抽出物留存率在高等大型真菌中，以1-3號菌種(55 %)較低。木質素留存率則以大型真菌(82.2 %)低於松針真菌(86.3 %)。顯示擔子菌類對於此等難以分解的物質之分解能力較強。 室內松針分解試驗中，接種大型真菌之重量留存率僅與碳濃度呈顯著負相關(R2 = -0.218)。碳、氮、磷、鉀、鈣、木質素大致上隨分解時間增加而減少，鎂、醇苯抽出物則未於分解時間上出現顯著差異。松針真菌之重量留存率則僅與木質素濃度呈顯著正相關(R2 = 0.473)。碳、氮、鉀、木質素大致上隨分解時間增加而減少，磷則呈現先增後減的趨勢，鈣呈出現先減後增的趨勢，醇苯抽出物則未隨時間增加而顯著減少。 野外試驗中，松針分解情形受溼度影響大。重量留存率僅與木質素達顯著正相關(R2 = 0.376)，養分間僅氮與醇苯抽出物達顯著正相關(R2 = 0.254)。碳、氮、鉀、木質素大致上隨分解時間增加而減少，磷則呈現先減後增再下降的趨勢，鈣、醇苯抽出物呈出現先減後增的趨勢。 由室內試驗結果顯示，擔子菌類對於台灣二葉松枯黃松針之分解能力優於子囊菌與不完全菌類，然因缺乏野外試驗部分，故有待進一步研究。

Abstract The purposes of this study are to examine the effects of different fungal inocula on pine needle decomposition to decrease the forest fire fuels accumulation. Microcosms containing sterile Pinus taiwaniensis needles were inoculated with 14 species of macrofungi (all Basidiomycetes isolated from in situ) together with 3 species of Ascomycetes and 1 species of Deuteromycetes isolated separately from interior and surface of pine needles in the laboratory. With the same time, litter bags inoculated with interior and surface fungi were placed in the litter layer of the pine plantation at Ta-Chia-His working circle. In all experiments, During the initial stages (0-2 months), the needle had the highest decomposition rate. The needles in microcosms were decomposed faster than those were in the field, it showed that the fungi had the potential ability to decompose pine needles under the suitable condition. For recalcitrant substrates, Basidiomycetes (isolated no. 1-3) showed the lowest remaining percentage (55 %) of extract with alcohol-benzene and 82.2 % of lignin, followed by those from Ascomycetes and Deuteromycetes. During the study period, the needles in microcosms inoculated with Basidiomycetes, the remaining mass had a significant negative correlation with C concentration (R2 = -0.218), the remaining percentage of C, N, P, K, Ca and lignin were decrease until the study end, the remaining percentage of Mg and extract with alcohol-benzene had no differences. However, those inoculated with Ascomycetes and Deuteromycetes, the remaining mass had a significant positive correlation with lignin concentration(R2 = 0.473), the remaining percentage of C, N, K and lignin were decrease until the study end. In the field, the needle decomposition was mainly affected by moisture. The significant positive correlation was existed between remaining mass and lignin concentration(R2 = 0.376), N concentration and extract with alcohol-benzene(R2 = 0.254). The remaining percentage of C, N, K and lignin were steady decreased until the study end. Based of the microcosms test, the decomposition abilities of Basidomycetes are batter than Ascomycetes and Deuteromycetes. However, further work involving the effects of different fungal inocula on pine needle decomposition in field is needed to confirm this conclusion.