合歡北峰台灣二葉松林火燒後之天然更新

Natural Regeneration of the Taiwan Red Pine (Pinus taiwanensis Hayata) Forest Following the 1990 Wildfire at Mt. North Hehuan in the Central Taiwan

台灣二葉松火燒後成功的天然更新，需有足夠的種源供應及苗木建立後能存活、生長至突出地被層，以確保不受競爭及環境因素之影響。本研究調查1990年2月合歡北峰台灣二葉松林火燒後苗木建立之過程、密度及齡級分布，並探討苗木分布及更新方式。調查區之台灣二葉松苗木於火燒後3年開始突出地被層，至7-8年可確定更新成功。整體苗木分布不均，有集中於母樹四周之現象，火燒後12年苗木密度為0.127 株／m2。火燒當年及次年建立之苗木dbh＞2 cm，樹齡為13或14年，約占現存苗木總數之37%。苗木於火燒後雖持續發生，然以火燒後初期建立之苗木存活及生長較佳，推論此與地被層恢復後，影響苗木之建立及生長有關。 After wildfire sufficient sources of seeds that survived and successful emergence of their seedlingsfrom the ground layer vegetation were two key factors that determined the success of naturalregeneration of the Pinus taiwanensis Hayata forest. We investigated the establishments, densities andage classes of P. taiwanensis seedlings following the wildfire of 1990 at Mt. North Hehuan, Taiwan. Theseedlings emerged from ground vegetation 3 years after the fire, and the forest regenerated successfully7-8 years after. Densities of the P. taiwanensis seedlings after 12 years were averaged at 0.127 trees/m2,and they were dispersed mainly around the mother trees. Seedlings established in the year of the fire andthe year after were, respectively, 14 and 13 years old with dbh of 2 to 10 cm. They occupied about 37%of the total seedlings.