英山县古树资源及其空间分布特征

Characteristics of Old Tree Resources and Their Spatial Distribution in Yingshan County

【目的】旨在系统研究湖北英山县古树资源的状况和分布特征,为古树的保护和管理提供参考。【方法】收集了英山县古树资源基础调查数据,并利用ArcGIS建立了古树的DEM分布网络;通过点格局分析探究古树的空间分布规律;应用Spearman和典范相关分析方法研究环境因素对古树生长的影响。【结果】调查到英山县目前有1 097株古树,隶属于22科36属50种;国家一、二级保护植物各有两种;全县的三级古树占全部古树数量的93.53%,一级和二级古树的数量相对较少。根据基于DEM网格和投影坐标网格的分析,较高海拔区域的人类聚集较少,而古树数量较多且生长较好;相反,较低海拔区域的古树数量较少且生长较差。当尺度超过11 km时,古树的分布由聚集逐渐转变为随机;而当尺度达到或超过14 km时,古树呈现均匀分布。古树的生长主要受到坡向的影响,而坡度对古树生长的影响相对较弱。【结论】森林环境和人类活动对古树的影响具有差异性,应针对古树的分布特征,制定相关的古树专业保护方案。

【Objective】The study aimed to systematically investigate the status and distribution char-acteristics of old tree resources in Yingshan County of Hubei Province,and to provide a reference for the protection and management of old trees.【Method】Based on basic survey data of the old tree resources,an old tree DEM distribution network was established by ArcGIS.The spatial distribution of old trees was analyzed by point pattern analysis.The influence of environmental factors on the growth of old trees was studied by Spearman and canonical correlation analyses.【Result】There were currently 1097 old trees surveyed in Yingshan County,belonging to 22 families,36 genera and 50 species.There were two spe-cies of plant under national first-level protection and two species under national second-level protection.Third-level old trees accounted for 93.53%of all old trees in the county,while the number of first level-and second-level old trees was very small.Based on DEM grid and projected coordinate grid,areas with higher altitude had fewer human settlements and more old trees with better growth;areas with lower alti-tude had fewer old trees with poorer growth;when the scale was>11 km,the distribution of old trees gradually changed from aggregation to random distribution,and when the scale was≥14 km,it became uniform distribution.The growth of old trees was mainly affected by slope aspect,while slope gradient had a weaker effect on the growth of old trees.【Conclusion】There are variations in the impact of forest environment and human activities on old trees.Therefore,specific professional conservation plans should be developed based on the distribution characteristics of ancient trees.