摘要
通过对沙地樟子松母树种子落种时空格局的观测,发现沙地樟子松种子大部分在高峰期集中飞散在母树周边,与母树距离的增加种子数量减少,在距离母树4m左右处,落种密度达到最大,且母树北侧和东侧的落种密度要高于南侧和西侧.此外文章还探讨了落种密度和距离与母树本身的关系,如树高和冠幅等,推算出了树高和扩散距离之间的量化关系,计算得出在已知风速的情况下沙地樟子松种子的最大扩散距离公式.最后将沙地樟子松种子更新过程分为母树、种子和幼苗阶段3个阶段和母树的结实与生产、种实扩散、种子萌发和幼树生长4个时期,从环境状况和母树自身特征角度分别探讨了沙地樟子松更新的影响因素,并在此基础上建立了沙地樟子松种子更新的时空模型.
Mongol Scotch Pine （ Pinus sylvestris L. var. mongolica Litv. ） distributes in the fixed sandy land and semi-fixed sandy land of the east of Hulun Buir Plateau and drainage basin formed by Hailar River, Yimin River and Halakhah River. Mongol Scotch Pine is adaptive to cold, drought and barren environments, with prominent regeneration ability to wind erosion control and shifting sand fixation. The natural regeneration process of Mongol Scotch Pine in sandy land is important to vegetation rehabilitation, degraded ecosystems reconstruction, sustainable sandy ecosystem benefit development, as well as establishment of green ecological barriers in the north of China. From the observation on the seed falling temporal and spatial distribution pattern of Mongol Scotch Pine mature individual plant, results show that seed distribution concentrates around the mother individual plant during the seed falling fastigium, and seed density decreases with the distance increase from the mother plant. The highest seed density exists at the site of 4 m from mother plant, and the seed density in the north and east is significantly higher than that in the west and north. The relationship between seed falling density and mother plant itself characteristics such as tree height and crown diameter is also discussed. The regeneration process of Mongol Scotch Pine has been divided into three stages and four phases. The temporal and spatial model of Mongol Scotch Pine regeneration has been built.
出处
《生态科学》
CSCD
2010年第5期403-410,共8页
Ecological Science
基金
中央级公益性科研院所基本科研业务费专项资金(CAFYBB2007042)
国家科技支撑项目(2006BAD26B01)
关键词
种子
天然更新
沙地樟子松
扩散机制
seed
natural regeneration
Pinus sylvestris L. var. mongolica Litv.
dispersal mechanism
