Stand structure as the basis of diversity index

Abstract Abundance of tree species and variation in tree size, age and genetic composition are the most relevant components of diversity in a forest stand. The aim of this study was to develop a within-stand diversity index and classification for between-stand diversity to meet these requirements. This, what may be called LLNS diversity index, was assessed by using the following indicator variables: stem distribution of live trees by tree species (stems ha −1 ), standing and fallen dead trees by tree species (m 3  ha −1 ), occurrence of special trees (number/significance) and charred wood (m 3  ha −1 ). The index was introduced as a scoring table for field use and as a mathematical formula for research and computerisation use. In the test material, this index served to differentiate the development classes of forest stands and site-types fairly well. The value of the index was at its highest in unmanaged, old-growth stands dominated by Norway spruce ( Picea abies (L.) Karst.). In single-tree selection stands, regularly all-sized stand structure resulted in a high diversity index values whereas low thinning, by evening out stand structure, reduced diversity. Classification of between-stand diversity was based on within-stand diversity scores, which were allocated to four quality levels (Excellent, Good, Satisfactory, Poor) by site-type.

[1]  Joseph Buongiorno,et al.  Tree Size Diversity and Economic Returns in Uneven-Aged Forest Stands , 1994 .

[2]  L. Gustafsson,et al.  Bryophyte flora and vegetation of managed and virgin coniferous forests in South-West Sweden , 1988 .

[3]  Ganapati P. Patil,et al.  A mathematical programming model for maintaining structural diversity in uneven-aged forest stands with implications to other formulations , 1995 .

[4]  S. Braatz.  Conserving biological diversity , 1992 .

[5]  R. Macarthur.  PATTERNS OF SPECIES DIVERSITY , 1965 .

[6]  R. Whittaker.  Evolution and measurement of species diversity , 1972 .

[7]  L. Gustafsson,et al.  Threatened Plant, Animal, and Fungus Species in Swedish Forests: Distribution and Habitat Associations , 1994 .

[8]  R. Alexander.  Silvicultural systems and cutting methods for ponderosa pine forests in the Front Range of the central Rocky Mountains , 1986 .

[9]  Benee F. Swindel,et al.  Species diversity: Concept, measurement, and response to clearcutting and site-preparation , 1984 .

[10]  M. Willson,et al.  Avian Community Organization and Habitat Structure , 1974 .

[11]  J. Larsen,et al.  Ecological stability of forests and sustainable silviculture , 1995 .

[12]  R. D. Ohmart,et al.  Comparison of the importance of different habitat attributes to avian community organization , 1984 .

[13]  T. Saksa,et al.  The Structure of Advanced Virgin Forests in Finland , 1991 .

[14]  K. Franzreb.  TREE SPECIES USED BY BIRDS IN LOGGED AND UNLOGGED MIXED-CONIFEROUS FORESTS , 1978 .

[15]  Malcolm L. Hunter,et al.  Wildlife, Forests and Forestry: Principles of Managing Forests for Biological Diversity , 1989 .