紅外線自動相機監測巒大杉人工林區塊伐過程動物組成的短期變化

Monitor short-term changes of animals with infrared automatic camera traps during patch cutting in Luanta fir plantation

本研究自2018年11月至2020年7月止，利用紅外線自動相機監測東勢林區管理處大安溪事業區117林班巒大杉人工林區塊伐過程野生動物的出現頻度與日活動模式。研究區分別於2017年與2018年進行區塊伐，平均一區塊伐採面積約1.70 ha，伐採後的造林樹種主要為臺灣杉，並混植少量牛樟。7臺紅外線自動相機總工作時數共102,444.6小時，總拍攝有效照片數721張，共記錄13種野生動物，包含9種哺乳類動物與4種鳥類。研究區以山羌、臺灣野山羊及臺灣獼猴為記錄頻度最高的物種。區塊伐過後，山羌、臺灣野山羊及臺灣獼猴在伐採區的出現頻度高於未伐採區，此現象可能因巒大杉人工林伐採過後，陽光、養分與空間等資源釋出，地被植物快速萌櫱新葉，或由土壤種子庫發芽的種子苗佔據，進而吸引動物前來取食。山羌及臺灣獼猴在較晚伐採的2018年伐區出現頻度高於2017年伐區，但臺灣野山羊並無明顯差異。全日活動模式結果顯示研究區的山羌、臺灣野山羊及臺灣獼猴以晨昏時段為活動高峰。本研究觀察亦發現，山羌與臺灣野山羊會啃食巒大杉萌櫱嫩枝，顯示這些草食獸可能對造林樹種苗木具有一定程度的毀損。因此，為降低草食獸的啃食損耗以提高造林成效，本研究建議若伐採區有草食獸分布時，造林樹種應選擇草食獸不偏好的種類，或是採取適當措施防範草食獸啃食目標造林樹種。

The changes in the occurrence index (OI) and activity pattern of wild animals were monitored using infrared automatic cameras from November 2018 to July 2020 during the patch cutting process of Cunninghamia konishii (Luanta fir) plantation in Compartment 117, Da-An-Xi Working Circle of Tung- Shi Forest District. Patch cutting was performed in the study area in 2017 and 2018. The average patch cutting area was approximately 1.70 ha, and the major planted tree species after cutting was Taiwania cryptomerioides mixed with a few Cinnamomum kanehirae trees. Seven infrared automatic cameras were installed, and 721 independent photographs were taken during 102,444.6 working hours. A total of 13 species were recorded, including 9 species of mammals and 4 species of birds. Muntiacus reevesi micrurus, Capricornis swinhoei, and Macaca cyclopis were the most frequently recorded species in the study area. The OI values of Mu. reevesi micrurus, Ca. swinhoei, and Ma. cyclopis were higher in the cutting-blanks than in the noncutting areas. The release of sunlight, nutrients, and space on the forest ground after the cutting of Cu. konishii plantation may result in an increased cover of ground vegetation from the understory, sprouted new leaves, and seedlings that attracted herbivores for food. The average OI values of Mu. reevesi micrurus and Ma. cyclopis in the cutting area were higher in 2018 than in 2017, but there was no significant difference in the OI of Ca. swinhoei. Regarding the activity pattern, Mu. reevesi micrurus, Ca. swinhoei, and Ma. cyclopis exhibited their peak activity at dawn and dusk in the study area. Moreover, Mu. reevesi micrurus and Ca. swinhoei consumed the sprouts of Cu. konishii, suggesting that these herbivores damage the seedlings of forest plantation. Therefore, to reduce the damage of seedlings by herbivores and improve the effect of afforestation, we suggest careful selection of tree species to be planted in the area. Furthermore, appropriate measures must be implemented to prevent herbivores from browsing the seedlings.