Thesis Abstract

the study examined the influence of age series on fibre characteristics of gmelina arborea established in mamu forest reserve,anambra state. three gmelina arborea stand of 20,22,and 27 years old were used for the study. wood samples were collected from the core wood,inner wood and outer wood at 10%, 50% and 90% of the tree merchantable height in accordance with the standard procedure (british standard specification, bs 373 (1989). the study examined the anatomical characteristics of gmelina arborea wood in respect to their age series such as fibre length, fibre diameter, lumen width and cell wall thickness were evaluated.
the mean fibre length of the age series were 0.9676 mm, 1.0705 mm and 1.1363 mm for 20, 22
and 27 years respectively. the   mean fibre diameter 0.0256 mm, 0.0269 mm and0.0249mm;mean lumen width 0.0293 mm, 0.0161 mm and 0.0179 mm;

Thesis Overview

1.0 INTRODUCTION                                              

Wood presents a unique challenge in use because of its variability and the directional nature of its basic structure. These are the sources of some of its attractive features but they require also that they be handled and applied in ways appropriate for good end use. The ways in which the structural features of the particular species determine their properties and limit the uses and applications can be studied more precisely (Jayeolaet al., 2009). Many attempts have been made to define wood quality (Keith 1985), but the definition proposed by (Mitchell 1961) appears to be the most widely cited: “Wood quality is the resultant of physical and chemical characteristics possessed by a tree or a part of a tree that enable it to meet the property requirements for different end products”.

As wood properties affect various aspects of the manufacturing process, wood quality must be defined in terms of the value of its end products. In addition, the definition needs to include serviceability, and cover attributes of interest to end-users, which may or may not have a direct impact on manufacturing, but will continue to matter long after the product has been sold and installed.   Wood fibres are usually cellulosic elements that are extracted from trees, straw, bamboo, cotton seed, hemp, sugarcane and other sources.

Because wood fibre is a natural material, wood fibre products contain many of the natural characteristics of wood in nature. This study is based on effect of age series on fibre characteristics of Gmelin aarborea.

1.2. Statement of problem

Wood has always been a material of great importance to mankind. It is highly versatile. The demand for wood has been on the  increase for various uses. Unfortunately, most of the wood species in the natural forest are going to extinction due to high demand by user leading to over exploitation. Therefore, the use of plantation grown wood species is a step toward meeting the demand and consumption of wood and wood products. Initially, G.arborea wood was established in the plantation with the aim of supply fibrous raw material to the then established pulp and paper mills in Nigeria.

Based on the targeted end-use of G. arborea, several studies have been conducted on its fibre characterization. However, there is no available information on the effect of plantation age on fibre characteristics of this wood species. Therefore, this study sought to bridge this knowledge gap.

1.3 Objectives

The general objective is to investigate the influence of plantation age on fibre characteristics of Gmelina arborea on wood utilization.The specific objectives are to:

1. Investigate the fibre characteristics of Gmelina arborea of different plantation age series.
2. determine the variation of fibre characteristics along bole length and across the radial direction of Gmelina arborea.

1.4 SCOPE OF STUDY
The research aimed to know the influence of ages on the fibre characteristics of Gmelina arborea on various end uses of wood particularly timber production and pulp & paper production.

1.5 Justification
Wood is a natural and a very variable material. This variability is attributed mostly to variations in the anatomical structure of wood. Despite its wide range of application, wood, like most other materials, should not be applied without thought for the conditions under which it will serve or for the inherent properties that will determine its suitability. As a biological material, wood reflects the conditions under which it was grown through the variations in its properties, which vary in different directions.

Jane (1967) recommended that the aspects of variation in wood structure are of practical importance in the industrial sense. It is important to know  the variation in species, genera and families of a tree species to observe the individuals of the same species and the variations occurring in the individual tree species as they grow older, from the pith outwards and from the bottom upwards.
Meanwhile, the wood of some tree species, by reasons of its inherent properties and variation in wood structure, is of no value as timbers; others because of their scarcity or their inaccessibility are only of local economic importance as timber.