Distance-Dependent Competition Measures for Predicting Growth of Individual Trees
Abstract:Modified distance-dependent competition indices were developed for predicting tree growth in plantations. These modified indices adjust the growth of an average tree up and down depending on the size of competitors as compared to the subject tree. A neighbor larger than the subject tree--dominant neighbor--places the subject tree at a competitive disadvantage, whereas a smaller neighbor--suppressed competitor--places it at a competitive advantage. Dead neighbors are included as a special kind of suppressed neighbor. Based on this philosophy, new versions and modifications of distance-weighted size ratio and area overlap indices were developed and compared to some previously published indices. Data from a spacing study established in eucalypt plantations in Portugal were used for the empirical aspects of this study. Single correlations with growth, on a spacing X age basis, were generally higher for the modified indices than for their original unmodified counterparts. Modified indices, in conjunction with stand-level variables, also performed well in multiple linear regression equations for predicting growth of individual trees. For. Sci. 35(3):816-831.
Document Type: Journal Article
Affiliations: Thomas M. Brooks Professor, Department of Forestry, VPI & SU, Blacksburg, VA 24061, USA
Publication date: September 1, 1989
More about this publication?
- Forest Science is a peer-reviewed journal publishing fundamental and applied research that explores all aspects of natural and social sciences as they apply to the function and management of the forested ecosystems of the world. Topics include silviculture, forest management, biometrics, economics, entomology & pathology, fire & fuels management, forest ecology, genetics & tree improvement, geospatial technologies, harvesting & utilization, landscape ecology, operations research, forest policy, physiology, recreation, social sciences, soils & hydrology, and wildlife management.
Forest Science is published bimonthly in February, April, June, August, October, and December.
2015 Impact Factor: 1.702
Ranking: 16 of 66 in forestry
Also published by SAF:
Journal of Forestry
Other SAF Publications
- Submit a Paper
- Membership Information
- Author Guidelines
- Ingenta Connect is not responsible for the content or availability of external websites