都市公園綠量視覺評估之研究

The Visual Evaluation of Green-mass of Urban Parks

都市公園發展已逾二世紀之久，然而，其在都市中所扮演的角色與機能隨著時代與社經之變遷而改變，在即將邁入廿一世紀之時，如何藉由合理而可行的系統方法，就此一兼具多重功能的都市開放空間重新加以診斷，以為未來既成公園更新及新設公園植栽設計之參考依據，乃當務之急。由相關研究文獻與法規可知，有關公園或都市開放空間植栽多寡之訂定皆十分模糊，且多以平面綠量為依據。然而，研究亦顯示，與其以空中攝影所拍攝的綠量，不如以在地上移動時映入眼睛的量來評價較為實際。本研究因此提出一套由觀賞者視覺偏好之觀點評估都市公園綠量之方法，以視覺偏好為理論基礎，植栽密度和植栽類型為研究變項，利用視覺影像模擬探討觀賞者對植栽綠量之偏好。最後透過實證研究探討既成都市公園綠量之偏好與計量，以為後續研究及都市公園更新與設計之參考依據。

Urban parks have a history of being developed for over two centuries. Its roles and functions have gradually changed according to the time period and changes in the society. Towards the coming of a new century, it is necessary to develop a reasonable and feasible evaluation model, for controlling the urban development to alleviate the deterionation of environment. From the review of literature and existing facts, it is realised that most of greenery criteria on urban parks or public open spaces are rather vague. Majority of the green-mass are counted on the bases of the vertical plant coverage. It is also evealed that the greenery index based on viewshed is more sensible than that of bird's-eye views. The present study intends to establish an evaluation model based on the theory of visual landscape preference and plant density and plant types as variables. Visual photomontage simulation is used to examine the observer's preference on green-mass. Finally, the recommended method is demonstrated by a case study in Taichung.