合水溪及椿谷溪流域植群之研究

Studies on the Vegetation of Hershueishi and Chuengushi Watersheds

毗鄰的合水溪及椿谷溪流域位於台灣中部北港溪上游，總面積約2373公頃，有69%位於惠蓀實驗林場內，包括16-19林班。本研究進行此集水區的植群調查、分類與製圖。由調查的59個樣區資料來分析植群結構及多樣性，並依植群分類結果繪製植群圖。植群分類採用雙向指標種分析法（TWINSPAN）與降趨對應分析法（DCA），共區分出3個群團、7個群叢，分別為：（I）烏心石群團：含著生珊瑚樹-假長葉楠群叢、紫珠葉泡花樹-長尾尖葉櫧群叢、狗骨仔-錐果櫟群叢；（II）三斗石櫟群團：含台灣赤楊-三斗石櫟群叢、台灣二葉松-栓皮櫟群叢；（III）山香圓群團：含鬼石櫟-山香圓群叢、台灣雅楠-山香圓群叢。植群型分布最主要的相關環境因子為海拔高度。區內共調查到151科439屬861種維管束植物，20種為稀有植物。本文之植群分類與製圖可供監測、保育及永續經營之參考。建議將本區保持原生狀態，以維續其生物多樣性。 There is natural and diverse vegetation in two neighbored watersheds of Hershueishi andChuengushi in central Taiwan. The vegetation of these areas was investigated, classified and mapped. 59plots were set up. 3 alliances and 7 associations were classified based on TWINSPAN and DCAanalyses. They are：(I) Michelia compressa ALL.：includes Viburnum arboricolum - Machilus japonicaASS., Meliosma callicarpifolia - Castanopsis cuspidata var. carlesii ASS., and Tricalysia dubia -Cyclobalanopsis longinux ASS.；(II) Pasania hancei var. ternaticupula ALL.：includes Alnus formosana - Pasania hancei var. ternaticupula ASS., and Pinus taiwanensis - Quercus variabilis ASS.；(III) Turpinia formosana ALL.：includes Lithocarpus lepidocarpus - Turpinia formosana ASS., andPhoebe formosana - Turpinia formosana ASS. DCA results reveal that elevation is the majorenvironmental factor affecting vegetation variation. Totally 861 species, belonging to 151 families and439 genera, were recorded in those areas. Among them, 20 species are rare species that have to be strictlyprotected. Vegetation classification and mapping of this study provide references for conservation andsustainable management of these watersheds. It is suggested to keep these areas in natural state formaintaining biodiversity.

There is natural and diverse vegetation in two neighbored watersheds of Hershueishi andChuengushi in central Taiwan. The vegetation of these areas was investigated, classified and mapped. 59plots were set up. 3 alliances and 7 associations were classified based on TWINSPAN and DCAanalyses. They are：(I) Michelia compressa ALL.：includes Viburnum arboricolum - Machilus japonicaASS., Meliosma callicarpifolia - Castanopsis cuspidata var. carlesii ASS., and Tricalysia dubia -Cyclobalanopsis longinux ASS.；(II) Pasania hancei var. ternaticupula ALL.：includes Alnus formosana - Pasania hancei var. ternaticupula ASS., and Pinus taiwanensis - Quercus variabilis ASS.；(III) Turpinia formosana ALL.：includes Lithocarpus lepidocarpus - Turpinia formosana ASS., andPhoebe formosana - Turpinia formosana ASS. DCA results reveal that elevation is the majorenvironmental factor affecting vegetation variation. Totally 861 species, belonging to 151 families and439 genera, were recorded in those areas. Among them, 20 species are rare species that have to be strictlyprotected. Vegetation classification and mapping of this study provide references for conservation andsustainable management of these watersheds. It is suggested to keep these areas in natural state formaintaining biodiversity.