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以位于浑善达克沙地宝绍岱苏木和那日图苏木的天然沙地榆为材料,测定沙地榆的年轮宽度、早材宽度和晚材宽度,分析其偏心生长状况、径向生长规律和径向生长动态,为浑善达克沙地榆树种群保护和天然更新提供依据。结果表明:宝绍岱和那日图生长的沙地榆均存在不同程度的偏心生长,且偏心形态比较复杂,形状不规则;宝绍岱和那日图沙地榆的径向生长过程中均出现了2个生长高峰期,其中年轮宽度和晚材宽度的径向生长规律非常相似,2次高峰期出现的时间完全一致,径向累积生长曲线均呈双S型;早材宽度在整个生长过程中的变化幅度很小,高峰期出现的时期与年轮宽度和晚材宽度相差比较大,累积生长曲线呈线型;宝绍岱和那日图沙地榆的平均生长量分别为2.25和2.30 mm,无显著差异,但宝绍岱沙地榆年轮宽度和晚材宽度的变异系数达到20%以上,明显大于那日图沙地榆;宝绍岱沙地榆径向生长第1次高峰出现在第17~21年,那日图沙地榆径向生长第1次高峰出现在第15~19年,二者的成熟龄相差3年。
The annual ring width, breadth of earlywood and latewood width of Ulmus pumila were measured using the natural sand Ulmus of Baoshao Dai and Namurosu located in the Hunshandake Sandy Land, and the eccentric growth was analyzed. Radial growth and radial growth dynamics, provide the basis for the protection and natural regeneration of elm populations in Hunshandake Sandy Land. The results show that both Baoshaodai and Saxiyu sagittarius exhibit eccentric growth to some extent, and the eccentric shape is complicated with irregular shape. In the radial growth process of both Baoshaoadai and Nadu sand, There are two growth peak, of which the radial growth of the ring width and latewood width of the law is very similar to the second peak appeared exactly the same time, the radial cumulative growth curve showed double S-type; width of the early wood in the whole The change in growth process was small, the period of peak appeared to be quite different from the width of annual ring and the width of latewood, and the cumulative growth curve was linear. The average growth of Baozodai and Nadu sand maple were 2.25 And 2.30 mm respectively. However, the variation coefficient of annual width and latewood width of Ulmus pumila was over 20%, which was obviously higher than that of Ulmus davidiana; The second peak appeared in the 17th to the 21st years, and the first peak of the radial growth of Ulmus was found in the 15th to 19th years, the difference between the mature ages of the two was 3 years.