科研之友
微信
新浪微博
Facebook
分享链接
摘要
The objective of the present work was to study the relationship between the density of trees per hectare and the average diameter of a Deciduous Forest, as well as to adjust the Reineke model to describe this behavior, comparing the performance of different methods. The area studied is in the municipality of Silveira Martins, in the central region of Rio Grande do Sul State, Brazil, and it is in early stage of succession after agricultural use. The number of the trees per hectare and the average diameter were obtained by the method of density-off proposed by Spurr. Samples were taken in early stages of a secondary forest, choosing areas with predominance of camboata-vermelho (Cupania vernalis). As natural forests have irregular spacing, density is quite variable. Therefore, in order to select only high-density plots, areas with occurrence of dead individuals were chosen. Different methods to estimate the upper limit of the self-thinning line were tested: regression analysis (for all data and relative density higher than 60%), correcting the intercept so that the residuals were negative; the manual adjustment; the relative density (DR>90%); the stochastic frontier analysis. The method that best estimated the maximum density was regression analysis with data from at least 60% of maximum density, with a slope of -1.563 for Reineke model. There was no significant difference between the powers provided by the methods.
- 出版日期2013-8
