海口市古树名木资源特征及其空间分布

依托海口市第2次古树名木资源普查，采用传统分析与GIS信息技术相结合的方法，对海口市古树名木资源的种类组成、植物区系、结构特征、生长势和空间分布格局进行统计分析。结果表明:（1）海口市共有古树名木1 684株（其中名木94株），隶属于28科45属51种。古树名木数量多且种类丰富；主要以桑科（Moraceae）、使君子科（Combretaceae）、棕榈科（Palmae）、无患子科（Sapindaceae）和含羞草科（Mimosaceae）等为优势科；以榕树（Ficus microcarpa）、高山榕（Ficus altissima）、见血封喉（Antiaris toxicaria）、榄仁树（Terminalia catappa）和椰子（Cocos nucifera）等乡土树种为主；海口市古树名木资源的科、属分布类型具有明显的热带性质和由热带向亚热带、温带过渡的特点。（2）海口市古树树龄结构呈三角形分布，即随树龄增大古树数量逐渐减少，表明海口市古树后续资源丰富。大部分古树名木的生长状态以正常为主，占总株数的64.72%，表明整体长势良好。（3）从空间分布格局看，海口市古树名木资源分布范围较为广泛，分布密度为0.736株·km?2。海口市古树名木分布的聚集程度很高，主要分布在海口府城、博爱等老城区，以及遵谭镇、新坡镇、三门坡镇、大坡镇、旧州镇和三江镇等城镇，反映出古树名木分布的历史文化特征。

Resource Characteristics and Spatial Distribution Pattern of Ancient and Rare Trees in Haikou,Hainan Island

Based on the second survey of ancient and rare trees resources in Haikou, the species composition, flora, structural characteristics, growth potential and spatial distribution pattern of the ancient and rare tree resources in Haikou were analyzed by using a combined method of traditional analysis and GIS information technology. The results showed that: 1 684 ancient and rare trees (94 were famous trees) were found in Haikou, belonging to 51 species in 45 genera of 28 families. These ancient and rare trees were abundant in quantity and species. The dominant families of these trees were Combretaceae, Palmae, Sapindaceae and Mimosaceae. The native tree species included Ficus microcarpa, Ficus altissima, Antiaris toxicaria, Terminalia catappa and Cocos nucifera. The Families and genera of the ancient and rare trees in Haikou were distributed with obvious tropical characteristics and transited from tropical to subtropical and temperate zones. The age structure of the ancient and rare trees in Haikou presented a triangular distribution, and the number of the ancient and rare trees gradually decreased with the age of the trees, reflecting that ancient and rare trees are abundant in the future. Most of the ancient and rare trees grew normal, accounting for 64.72% of the total, indicating that the ancient and rare trees were growing well as a whole. From the perspective of the spatial distribution pattern, the ancient and rare trees in Haikou were widely distributed, with a density of 0.736 plants·km?2. The ancient and rare trees in Haikou showed a highly aggregated distribution, and were mainly distributed in the old towns in Haikou such as the old town areas like Fucheng and Boai, as well as in other towns like Zuntan Town, Xinpo Town, Sanmenpo Town, Dapo Town, Jiuzhou Town, and Sanjiang Town, reflecting the historical and cultural characteristics of the distribution of the ancient and rare trees. Some suggestions were made based on the analysis of the surveys for the protection and management of the ancient and rare trees in Haikou.