西藏核桃古树分布格局及树龄研究

Study on Distribution Pattern and Tree Age of Ancient Juglans regia in Tibet Autonomous Region

根据现有的西藏核桃古树资源调查资料,对西藏自治区核桃古树分布格局及树龄进入深入研究,为西藏自治区核桃古树资源保护与制定保护策略及开发提供借鉴和指导作用。本研究运用网格法,通过分别计算扩散系数、负二项参数、Cassie指数、丛生指数以及聚块性指标分析西藏自治区核桃古树的分布格局,同时对西藏全区的核桃古树胸围与树龄的回归模型y=517.59ln(x)-2681.8(R^(2)=0.7605)进行模型验证。西藏自治区核桃古树呈聚集分布。当胸围在380~750 cm时,模型验证效果最为可靠。回归模型y=517.59ln(x)-2681.8(R^(2)=0.7605)是能较准确地适用于全区范围内胸围在380~750 cm核桃古树估龄的。

According to the existing survey data of ancient Juglans regia resources in Tibet,the distribution pattern and tree age of ancient J.regia in Tibet Autonomous Region have been deeply studied,which can provide reference and guidance for the protection and the formulation of protection strategies and development for ancient J.regia resources in Tibet Autonomous Region.In this study,the grid method was used to analyze the distribution pattern of ancient J.regia in Tibet Autonomous Region by respectively calculating various indices,such as the diffusion coefficient,negative binomial parameter,Cassie index,clumping index and clustering index.At the same time,the regression model y=517.59ln(x)-2681.8(R^(2)=0.7605)of the breast circumference and age of ancient J.regia in Tibet was verified.The ancient J.regia in Tibet Autonomous Region were clustered,and the model verification effect was the most reliable when the breast circumference ranged from 380 to 750 cm.The regression model y=517.59ln(x)-2681.8(R^(2)=0.7605)can be more accurately applied to estimate the age of ancient J.regia with breast circumference at 380~750cm in the whole area.