基于林分关键指标的云南省云南松地理分布格局

云南松是云南省重要的森林资源,其林分普遍存在退化情况,对其提质增效已是紧迫的任务,但目前尚缺乏全省云南松林分质量及其地理分布格局的定量评价作为参考。本文用MaxEnt模型,结合350个云南松分布点和47个环境变量,获得云南松适生区范围;并通过Arcgis 10.2平台,在云南松适生范围区内对1500个云南松小班的3个关键指标,即公顷蓄积、年龄、生长速度进行插值和分级计算,获得全省范围内各指标分级及其地理分布格局。结果显示:总体上,云南松林分的公顷蓄积、生长速度处于较低的等级,而年龄结构为衰退型;生境退化、优良种源丧失、自然演替被打断等因素,是造成云南松在整体分布上年龄结构不合理、生长速度慢和公顷蓄积低等退化特征的原因;建议对现有云南松林进行提质增效,对优良种源进行集中经营,促进地带性植被演替进程的恢复。本研究为云南省森林资源的可持续经营提供参考。

Geographical Distribution Patterns of Pinus yunnanensis in Yunnan Province Based on Critical Indicators of the Forest Stand

Pinus yunnanensis is an important forest resource in Yunnan Province,but its stand is generally degraded,so it is urgent to improve its comprehensive quality and efficiency,but there is still a lack of quantitative evaluation of P.yunnanensis stand’s quality and its geographical distribution patterns.In this paper,the potential distribution area of P.yunnanensis was obtained by using MaxEnt model,combined with 350 distribution pilot samples and 47 environmental variables.Three key indexes in 1500 P.yunnanensis subclasses,hectare stock,age and growth rate,were interpolated and graded by arcgis 10.2 platform,and the classification of each index and its geographical distribution pattern in provincial level were obtained.The results showed that the stand of P.yunnanensis was in a low grade of hectare stock and growth rate,while the age structure was in a declining trend.The human disturbance,such as habitat degradation,loss of fine breeds,and interrupted natural succession of vegetation were discussedin the degradation P.yunnanensis forest.That presents irrational age structure,slow growth rate and low hectare stock in the general distribution of P.yunnanensis.It is suggested that to improve the quality and efficiency of the existing P.yunnanensis forest should strengthen the lumped management of fine breeds to avoid provenance mixture and promote the restoration of natural succession of regional vegetation.The results provide a scientific reference for the sustainable management of P.yunnanensis forests in Yunnan Province.