Abstract:
Comparison between densities of Ailanthus excelsa wood obtained by physical methods and an anatomical method
This investigation aimed at estimate the density and specific gravity of Ailanthus excelsa by physical and anatomical methods, and find relationships between different densities as dependent variables and anatomical properties as independent variables. The investigation also aimed at finding weather or not the anatomical methods will give reliable values of density. The standard physical methods were used to find different types of densities.
Stereological techniques were used to find volume fraction of different cell components. The results revealed that the average of total cell wall volume fraction was 0.3620833, while average of the of total cell lumen fraction was 0.625833.the anatomical density was calculated from cell wall volume fraction.
Analysis of variance was also carried out to find significant differences between all types of densities. Significant differences were found between all types of densities. The results showed that the average green density (0.62500﴿ was the highest followed by anatomical density (0.5567﴿, equilibrium density (0.4215﴿, specific gravity (0.39375﴿and lastly basic density with an average of (0.3400﴿ with significant difference between all types of densities.
Then the anatomical density was obtained by multiplying 1.54 by the volume fraction cell wall. Regression analysis was also carried out to find relationships between different densities as dependent variables and anatomical properties as independent variables.
Different models were derived from these analyses only tow models were significant. The first model was that relating anatomical density with the volume fraction of cell wall with R2 = 0.9956 and P= 0.0001. And the second was the model relating anatomical density and volume fractions of cell lumen and cell wall with R2 = 0.9954 and P= 0.0001.
