Abstract

The geographical distribution of Lilium philippinense Baker in the Cordillera Central Range (CCR), Luzon Island, Philippines has not been accurately recorded in previously published literature. The need for this type of study for L. philippinense becomes more immediate due to the decline of its population. The output of this paper is the identification, establishment and description of the geographic distribution of L. philippinense, an endemic species in the region through extensive survey of the entire CCR. Mapping the 118 natural populations of L. philippinense in the entire study area using Geographical Information System (ArcMap of ArcGIS 9) shows a narrow and fragmented distribution pattern, specifically on the southwestern slopes of the CCR. Descriptive analyses reveals that the populations are distributed at an altitudinal range of 754 and 2,155 m and geographically located between 16º27’90” and 17º15’55” latitude and 120º51’86” and 121º09’22” longitude. In addition, results of hierarchical cluster analyses and analysis of variance also show that elevation plays a major role in the distribution of this species. Moreover, threats to this species are also determined. Information derived from this study can be of aid to biologists and conservationists in developing strategies to protect this endemic and threatened species.

中文摘要

菲律賓百合（Lilium philippinense Baker）在菲律賓呂宋島中央山脈區域（Cordillera Central Range, CCR）的地理分布，在以前出版的文獻中尚未有準確記錄；由於菲律賓百合族群數量的下降，此類型研究的需要變得更直接且迫切。本文藉由廣泛的調查整個中央山脈區域，來鑑識、建立並描述當地固有種菲律賓百合的地理分布。利用地理資訊系統（ArcMap, ArcGIS9）測量描繪整個研究區中118個菲律賓百合自然種群，顯示了其狹窄和片段的分布格局，特別是中央山脈區域的西南山坡上。描述性分析顯示種群分布範圍在海拔754和2,155公尺之間，地理位置於北緯16º27'90''和17º15'55''間、東經120º51'86''和121º09'22''之間。此外，階層群集分析的結果和方差分析也表示，海拔對此物種分布扮演重要的角色。本文也判斷該物種所受的威脅。本研究所提供的訊息可以協助保育生物學家制定策略以保護這個特有且受威脅的物種。

Keyword: Cordillera Central Range, distribution, fragmented, geographic location, GIS.中央山脈區域、分布、片段的、地理位置、地理資訊系統。