Tree Size Structure of Tectona grandis (Linn f.) Stand in Hilltop and Valley-Bottom of Omo Forest Reserve (original) (raw)
Related papers
2004
Phytosociological studies were carried out in an age series Teak plantation (1, 5, 11, 18, 24 and 30 years). In these stands average basal area increased with growing age. Density had inconsistent relationship but indicated towards a decrease, as the plantations grew older. In the case of shrubs also density had the same trend. Association of certain species with original vegetation was retained while few new ones got introduced during the course of time. Seasonal record of herbs indicated that total number of species was highest in rains followed by summer and winter seasons. An interesting finding of this study was that higher number of species was found in artificially regenerated Teak plantations in comparison to the original natural Sal forests.
Basal Area-Stump Diameter Models for Tectona grandis Linn. F. Stands in Omo Forest Reserve, Nigeria
The tropical forests in developing countries are faced with the problem of illegal exploitation of trees. However, dearth of empirical means of expressing the dimensions, structure, quality and quantity of a removed tree has imped conviction of offenders. This study aimed at developing a model that can effectively estimate individual tree basal area (BA) from stump diameter (Ds) for Tectona grandis stands in Omo Forest Reserve, Nigeria, for timber valuation in case of illegal felling. Thirty-six 25 m×25 m temporary sample plots (TSPs) were laid randomly in six age strata; 26, 23, 22, 16, 14, and 12 years specifically. BA, Ds and diameter at breast height were measured in all living T. grandis trees within the 36 TSPs. Least square method was used to convert the counted stumps into harvested stem cross-sectional areas. Six basal area models were fitted and evaluated. The BA-Ds relationship was best described by power model which gave least values of Root mean square error (0.0048), prediction error sum of squares (0.0325) and Akaike information criterion (-15391) with a high adjusted coefficient of determination (0.921). This study revealed that basal area estimation was realistic even when the only information available was stump diameter. The power model was validated using independent data obtained from additional plots and was found to be appropriate for estimating the basal area of Tectona grandis stands in Omo Forest Reserve, Nigeria.
Growth Performance of Tectona Grandis in Community and Private Plantation
2019
Globally the forest area covers 3,999 million ha (30.6%) of land. About 299 million ha (7%) of this is planted forest which had been increased by 105 million ha since 1990 (FAO, 2016). T. grandis plantation forest constitutes about 4.346 million ha and represents 75% of high tropical hardwood plantation, 83% of which is in tropical Asia (IUFRO, 2018). Teak (Tectona grandis L.F., is a member of Verbenaceae family, one of the most important, widely planted, a valuable hardwoods spp. (Robertson and Reilly, 2006). The success of large scale plantation is mainly due to its relatively fast growth, fire resistance, non-browsability, high survivable rate (Robertson and Reilly, 2006). Besides, it is termite resistance and widely used for boat and ship, building construction, decorative veneer, furniture, handicraft, musical instruments and has been recognized for centuries as a king among timbers due to its durability, workability, attractiveness and strength (KFRI and ITTO, 2003; FAO, 2016,...
Journal of Forest Science and Environment, 2017
Sustainable management of plantations can increase carbon sequestration potentials and contribute to climate change mitigation. However, carbon stock estimates are scarce in most tropical forests. This study estimated above- and belowground biomass and developed biomass equations for stock estimation in three age series of Tectona grandis, using an inventory approach. Sample plots (20m x 20m) were laid in 5-, 10-, and 15-year old Tectona grandis plantations. All the trees within the plots were enumerated for total height and diameter at breast height (DBH). The DBH of two trees in each age series of Teak stand that was closest to the mean DBH were selected for destructive sampling to estimate the biomass. Thus, samples of roots, leaves as well as stem discs were collected at the base, DBH, middle point and merchantable height and were oven-dried to determine the moisture content and dry weight. Inventory and biomass data were analysed using descriptive and inferential statistics at p< 0.05 level of significance. The biomass equations were also developed using regression analysis. The growth variables increased with age, with mean DBH of 4.43cm, 18.02cm and 21.12cm for the 5, 10 and 15-year-old stands, respectively. Similarly, the mean heights were 4.02m, 15.99m and 17.57m. Carbon stocks increased in the 5, 10 and 15-year-old stands with 81.18C/ha, 476.58C/ha and 864.88C/haestimated respectively. The models: LogB = -3.805 + 2.618LogDBH; and LogB = -34.009 + 2.316LogDBH gave the best fits for the 5 and 15-year-old stands, while LogB = -2.410 + 0.481LogDBH + 2.185LogH gave the best fit for the 10-year-old stand. Hence, DBHand height parameters are suitable variables for developing allometric equations and predicting biomass of Tectona grandis in plantations.