| The growth patterns, wood anatomic features and basic density of Chinese Wingnut (Pterocarya stenoptera C DC) were reported; and the increments, wood anatomic features and wood basic density in different environments were compared in this paper.The current annual increment (CAI) of tree height increases from the 1st year to the 5th year, afterward it decreases rapidly and then levels off after the 10th year. The fast-growing period of tree height is between the 5th and 9th year. The CAI of diameter at breast height (DBH) increases till the 6th year, reaching the peak value at 2.11cm per annum, and levels off after the 10th year. The CAI of trunk volume reaches its summit at the 9th year and lasts to the 14th year, which comes later and lasts longer than that of the tree height and the ring width.From the pith to the bark, the fiber length first increases rapidly, and then increases slowly and levels off after 8 ages. The fiber width, diameter, double wall thickness as well as double wall thickness to diameter ratio increases all along, maximum at the 11th ring, outward it decreases slightly. The fiber diameter to width ratio decreases gradually and levels off after the 9th ring. Along the stem height, the fiber length increases to 3.3- 5.3m of the tree height, reaching the maximum 1174um, and then decreases slowly to the top of the tree. The fiber width increases all along, contrary to the fiber diameter and double wall thickness to diameter ratio. The fiber double wall thickness increases to 5.3m of the tree height, levels off to 11.3m, and then decreases to the top of tree. The fiber length to width ratio and double wall thicknessincrease respectively to 9.3m and 7.3m of the tree height, and then level off. From the pith to the bark and from the base to the top of tree, the mean values of the fiber length, width, diameter, double wall thickness, length to width ratio, diameter to width ratio and double wall thickness are 1145um, 26.9um, 18.8um, 8.1um, 43.2, 0.70, 0.46 and 1077um, 26.3um, 18.4um, 7.9um, 38.8, 0.70, 0.45, respectively.With the increasing of age, the vessel-elements length, width, diameter and double wall thickness increase correspondingly, contrary to the vessel-elements double wall thickness to diameter ratio. The vessel-elements length to width ratio also increases in fluctuation with the increasing of age. The vessel-elements diameter to width ratio increases firstly before 9th ring, and then decreases. From the base to the top of tree, the vessel-elements length increases firstly to 5.3m of the tree height, reaching the maximum value, and then decreases. So do the vessel-elements width and diameter, but the latters'maximum value are at 3.3m of the tree height. The vessel-elements double wall thickness increases from the base to 15.3m height of tree, upward it drops rapidly. Both the vessel-elements length to width ratio and double wall thickness to diameter ratio submits to the trend of increase by degrees along the tree height,only the fluctuation of the length to width ratio is more intense than that of the double wall thickness. The vessel-elements diameter to width ratio decreases from the base to the top of tree. The mean values of the vessel-elements length, width, diameter, double wall thickness, length to width ratio, diameter to width ratio and double wall thickness are 461 um,174.0um, 163. 2um, 10.3um, 2.70, 0. 94, 0. 07, individually.The mean value of the basic density is 0.3791 g/cm3, and CV 16.49%. The basic density increases all along from the pith to the bark or from the base to the top. Only slight negative correlation was found between the basic density and the tree height, DBH, trunk volume and the ring width and there is no significant difference at 0.05 levels. The results demonstrate that the basic density dropped little in fast-growing trees of P. stenoptera. The fiber length has only little influence on the basic density among the same growth rings at different height of tree, and significant correlation at 0.01 levels was found betwee... |
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