Adjustments of individual-tree survival and diameter-growth equations to match whole-stand attributes

This article is part of a larger document. View the larger document here.

  • Authors: Cao, Quang V.
  • Publication Year: 2010
  • Publication Series: General Technical Report (GTR)
  • Source: In: Stanturf, John A., ed. 2010. Proceedings of the 14th biennial southern silvicultural research conference. Gen. Tech. Rep. SRS–121. Asheville, NC: U.S. Department of Agriculture, Forest Service, Southern Research Station. 369-373.

Abstract

Individual-tree models are flexible and can perform well in predicting tree survival and diameter growth for a certain growing period. However, the resulting stand-level outputs often suffer from accumulation of errors and subsequently cannot compete with predictions from whole-stand models, especially when the projection period lengthens. Evaluated in this study were five methods for adjusting the tree-survival equation to match observed number of trees per acre and three methods for adjusting the diameter-growth function to match observed basal area per acre. The evaluation procedures were repeated for adjustments using outputs from a whole-stand model. The different methods for adjusting tree survival probability and diameter growth were found to produce similar results. The methods selected (one for survival probability and another for diameter growth) both involved direct computation of the adjustment factor. Use of observed stand attributes for adjustment resulted in improvement of tree-level predictions of the individual-tree model. On the other hand, when predicted stand densities were used for adjustment, the quality of the tree-level predictions depended on the reliability of the stand predictions.

  • Citation: Cao, Quang V. 2010. Adjustments of individual-tree survival and diameter-growth equations to match whole-stand attributes. In: Stanturf, John A., ed. 2010. Proceedings of the 14th biennial southern silvicultural research conference. Gen. Tech. Rep. SRS–121. Asheville, NC: U.S. Department of Agriculture, Forest Service, Southern Research Station. 369-373.
  • Posted Date: August 12, 2010
  • Modified Date: October 14, 2010
  • Print Publications Are No Longer Available

    In an ongoing effort to be fiscally responsible, the Southern Research Station (SRS) will no longer produce and distribute hard copies of our publications. Many SRS publications are available at cost via the Government Printing Office (GPO). Electronic versions of publications may be downloaded, printed, and distributed.

    Publication Notes

    • This article was written and prepared by U.S. Government employees on official time, and is therefore in the public domain.
    • Our online publications are scanned and captured using Adobe Acrobat. During the capture process some typographical errors may occur. Please contact the SRS webmaster if you notice any errors which make this publication unusable.
    • To view this article, download the latest version of Adobe Acrobat Reader.