Comparative study of some non-linear models for predicting the yield of Gmelina arborea plantation.
Journal Title: Journal of Applied and Natural Science - Year 2014, Vol 6, Issue 2
Abstract
Yield models are important for effective forest management and as such were developed for the University of Benin Gmelina arborea plantation, Nigeria. The objectives of the study were to develop, evaluate and compare predictions from some non-linear models for timber volume estimation. A total of nine non-linear models comprising of three models each for weibull, logistic and log-normal models were developed using the three independent variables combinations (Basal area and merchantable height, diameter at base and merchantable height, diameter at middle and merchantable height). The assessment criteria (correlation coefficient (R), coefficient of determination (R2), standard error of estimate (SE)) with the validation results (using percentage bias and probability plots of residuals) showed that all categories of weibull and logistic models generated in this study discovered to be very adequate for tree volume estimation. The highest R2 (93.80), lowest SE (0.25) and lowest bias% (1.29) in the study were achieved from Weibull model 1a. The log-normal models were the least adequate for tree volume estimation with the highest bias%. The one way analysis of variance revealed that there were no significant differences in the performance of the non-linear models when varying predictor variables were used. The weibull, logistic models were therefore recommended for further use in this ecosystem and in any other forest ecosystem with similar site condition. Keywords: Gmelina arborea, Plantation.
Authors and Affiliations
F. Oboite, V. Ade-Oni
Antioxidant activity and production of secondary metabolites of adult plant and in vitro calli of Anodendron paniculatum
The members of the family Apocynaceae are the rich in alkaloids, terpinoids, flavonoids, phenolic compounds and hydrocarbons. Anodendron paniculatum Roxb. is an woody climber, the roots of which have been used to control...
Biocontrol of toxigenic strain of Aspergillus flavus isolated from the root tubers of safed musli (Chlorophytum borivilianum Sant. F) using its rhizospheric mycoflora
Miraculous herb safed musli (Chlorophytum borivilianum Sant. F), family liliaceae, is well recognized for its immense potential as an aphrodisiac. The root tubers of this herbal drug were found to be invested with Asperg...
Musculoskeletal disorders amongst workers of glass manufacturing unit of Western Uttar Pradesh
Glass manufacturing process is a very tiresome job and the working near by the furnace makes tasks more difficult for workers as the environment is very hot. Apart from working in a hot environment various awkward postur...
Effects of agro-chemicals practices in economic production of cabbage in valley districts of Manipur, India
Present investigation was conducted in Thoubal district and Imphal East district of Manipur, India to assemble the information about the economics of cabbage production, checking the practices done by farmers while using...
Antimicrobial photodynamic therapy and its applicability in aquaculture systems and aquatic animal health management: An overview
Global aquaculture production in 2012 touched new high of 90.4 million tonnes including 66.6 million tonnes of food fish and 23.8 million tonnes of aquatic algae providing 19.2 kg per capita food fish suppy. Aquaculture...