Growth rate and ring width variability of teak, Tectona grandis (Verbenaceae) in an unmanaged forest in East Timor
Teak (Tectona grandis) is one of the most valuable timbers in international trade and an important species for tropical forestry. Teak is found on the island of East Timor but no information is available on teak growth from this region. A pure stand planted in 1940-50 in the North of East Timor and...
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| Format: | Article |
| Language: | English |
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Universidad de Costa Rica
2012-03-01
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| Series: | Revista de Biología Tropical |
| Subjects: | |
| Online Access: | http://www.scielo.sa.cr/scielo.php?script=sci_arttext&pid=S0034-77442012000100036&lng=en&tlng=en |
| _version_ | 1827163789490913280 |
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| author | Vicelina B. Sousa Sofia Cardoso Teresa Quilhó Helena Pereira |
| author_facet | Vicelina B. Sousa Sofia Cardoso Teresa Quilhó Helena Pereira |
| author_sort | Vicelina B. Sousa |
| collection | DOAJ |
| description | Teak (Tectona grandis) is one of the most valuable timbers in international trade and an important species for tropical forestry. Teak is found on the island of East Timor but no information is available on teak growth from this region. A pure stand planted in 1940-50 in the North of East Timor and left unmanaged was studied. Fifteen trees were sampled in October-November 2003 and stem discs taken at three height levels of its height (1.7m, 9.5m and 18.7m), and cores were collected at DBH. Transverse surfaces of the discs and cores were polished for ring identification. Core cross sections were first digitized and disc cross sections were observed under the microscope. Three randomly selected radii were analyzed in each disc. Ring width measurement and ring counting were done using image analysis software. The distinction between heartwood and sapwood was performed macroscopically by colour difference, and heartwood radius and sapwood width were measured. The relationship between stem and heartwood radius was studied for each disc and heartwood percentage by radius was determined. Radial ring width curves are presented for the different axial positions within the stem, and ring width variability was analyzed. Growth rates were calculated and age-radius relationships were estimated using cumulative growth curves. Growth rings were large and well defined in the juvenile phase, reflecting the specie’s fast-growing character. The year-to-year variation of ring width showed a similar pattern among trees. Mean ring width ranged between 4.3-7.3mm for the first 20 years and 3.3-5.1mm for 30 to 45 years. Pith eccentricity was evident in the lower part of the stem and ring wedging occurred. On average, heartwood represented 84% of the radius and sapwood contained 6 to 11 rings. The age-related variation of ring width and the occurrence in the lower part of the tree stems of eccentricity and wedging rings, highlights the importance of appropriate stand management, particularly regarding basal density distribution over time, whenever optimized timber production is envisaged. |
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| format | Article |
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| institution | Directory Open Access Journal |
| issn | 0034-7744 |
| language | English |
| last_indexed | 2025-03-21T01:06:17Z |
| publishDate | 2012-03-01 |
| publisher | Universidad de Costa Rica |
| record_format | Article |
| series | Revista de Biología Tropical |
| spelling | doaj.art-b4c3714c814341388e3b940ae091c91c2024-08-03T03:34:38ZengUniversidad de Costa RicaRevista de Biología Tropical0034-77442012-03-01601483494S0034-77442012000100036Growth rate and ring width variability of teak, Tectona grandis (Verbenaceae) in an unmanaged forest in East TimorVicelina B. Sousa0Sofia Cardoso1Teresa Quilhó2Helena Pereira3Universidade Técnica de LisboaUniversidade Técnica de LisboaInstituto de Investigação CientíficaUniversidade Técnica de LisboaTeak (Tectona grandis) is one of the most valuable timbers in international trade and an important species for tropical forestry. Teak is found on the island of East Timor but no information is available on teak growth from this region. A pure stand planted in 1940-50 in the North of East Timor and left unmanaged was studied. Fifteen trees were sampled in October-November 2003 and stem discs taken at three height levels of its height (1.7m, 9.5m and 18.7m), and cores were collected at DBH. Transverse surfaces of the discs and cores were polished for ring identification. Core cross sections were first digitized and disc cross sections were observed under the microscope. Three randomly selected radii were analyzed in each disc. Ring width measurement and ring counting were done using image analysis software. The distinction between heartwood and sapwood was performed macroscopically by colour difference, and heartwood radius and sapwood width were measured. The relationship between stem and heartwood radius was studied for each disc and heartwood percentage by radius was determined. Radial ring width curves are presented for the different axial positions within the stem, and ring width variability was analyzed. Growth rates were calculated and age-radius relationships were estimated using cumulative growth curves. Growth rings were large and well defined in the juvenile phase, reflecting the specie’s fast-growing character. The year-to-year variation of ring width showed a similar pattern among trees. Mean ring width ranged between 4.3-7.3mm for the first 20 years and 3.3-5.1mm for 30 to 45 years. Pith eccentricity was evident in the lower part of the stem and ring wedging occurred. On average, heartwood represented 84% of the radius and sapwood contained 6 to 11 rings. The age-related variation of ring width and the occurrence in the lower part of the tree stems of eccentricity and wedging rings, highlights the importance of appropriate stand management, particularly regarding basal density distribution over time, whenever optimized timber production is envisaged.http://www.scielo.sa.cr/scielo.php?script=sci_arttext&pid=S0034-77442012000100036&lng=en&tlng=enTectona grandisanillos de crecimientoanchura de anillosduramenvariación |
| spellingShingle | Vicelina B. Sousa Sofia Cardoso Teresa Quilhó Helena Pereira Growth rate and ring width variability of teak, Tectona grandis (Verbenaceae) in an unmanaged forest in East Timor Revista de Biología Tropical Tectona grandis anillos de crecimiento anchura de anillos duramen variación |
| title | Growth rate and ring width variability of teak, Tectona grandis (Verbenaceae) in an unmanaged forest in East Timor |
| title_full | Growth rate and ring width variability of teak, Tectona grandis (Verbenaceae) in an unmanaged forest in East Timor |
| title_fullStr | Growth rate and ring width variability of teak, Tectona grandis (Verbenaceae) in an unmanaged forest in East Timor |
| title_full_unstemmed | Growth rate and ring width variability of teak, Tectona grandis (Verbenaceae) in an unmanaged forest in East Timor |
| title_short | Growth rate and ring width variability of teak, Tectona grandis (Verbenaceae) in an unmanaged forest in East Timor |
| title_sort | growth rate and ring width variability of teak tectona grandis verbenaceae in an unmanaged forest in east timor |
| topic | Tectona grandis anillos de crecimiento anchura de anillos duramen variación |
| url | http://www.scielo.sa.cr/scielo.php?script=sci_arttext&pid=S0034-77442012000100036&lng=en&tlng=en |
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