薹灣上新世之孢粉分析沄水溪剖面

Abstract

分析臺灣西南部沄水溪剖面57個樣品，記述了6個新屬，53個新種，1個新變種，5個新記錄種及2個新組合種。新發現之被子植物花粉與其他地區記錄比較，其出現之時序多能相符，而馬錢科之灰莉粉及敗醬科之敗醬粉則尚未有確定之記錄以資對照。隆脊條紋孢型之向心極面網紋，未發現於現生類似孢型中，其可能為一較原始之特徵。 將歸屬於冷溫及暖溫熱植?兩類之孢粉型或生長環境相似之孢粉組合，製作孢粉圖譜，冷溫植?與暖熱植草有相對的變化，以其變化為主，劃分了①愷木粉一楓楊粉微量帶②冷杉一雲杉粉－杉粉衰退帶③角蘚出現帶④水蕨孢突增帶⑤摺凸孢消失帶⑥杉粉－禾草粉漸增帶⑦殼鬥科粉－杉粉穩定帶⑧冷熱消長帶等八個孢粉帶。氣候變化在冷杉－雲杉粉－杉粉衰退帶氣溫有趨暖之勢，水蕨孢突增帶顯示有濕熱之環境。於杉粉－禾草粉漸增帶氣候有轉為乾冷之可能，殼鬥科粉－杉粉穩定帶則回復濕熱環境。冷熱消長帶之氣溫有劇烈的冷－熱－冷變化，可能已屬更新世。 屬於白堊紀晚期及第三紀早期孢粉之再堆積及裸棣農藻之出現，推論漏水溪剖面之地層堆積時有白堊紀海相沈積地層之出露。

Fifty-seven samples taken along Yunshuichi section in southwestern Taiwan are palynologically analyzed; six new genera, fifty-three new species, five new records, one new variety and two new combination are proposed. The new angiospermoun: teas in this study are compared with Muller's review (1991). These new taxa are in accordant with the timeocurse of appearance with several areas outside Taiwan. But Fegraea and Patrinia types have not yet been sufficiently documented in the past. Two pollen assemblages, i.e., cola to warm and subtropical to tropical assemblages are unvilized to subdivide the pollen zones. The ourves of those two □□ somewhat □ alternations. Eight pollen zone □ namely, AP-, AT-, AN-, MA-, CO-, TG-, FT- and CE-zone. The □ in the AT-zone; damp and hot in MA-zone; cold and dry in TU-zone; damp and warm in FT-zone. CH-zone has prominent temperature changs from cold to hot and again cold. Therefore, CE-zone might belong to the early Pleistocene stare. The reworked polynomorphs from Cretaceous and early Tertiary deposits were causally found. Based on the reworked palynomorphs including □, a wide spread marine dinoflagellate in upper Creataceous, the presence of outorops of Cretaceous marine deposits in the sedimentary cycle of Yunshuichi section was inferred.