黄山松群落林隙光能效应与黄山松的更新

Light effect of gaps in Huangshan pine community and regeneration of Huangshan pine

研究安徽黄山海拔1400～1600m垂直带自草甸发育的黄山松林分的林隙,采用林隙周边树木年轮生长序列分析方法来推测林隙形成的时间,结果表明林隙形成与更新发生的时间基本相近.通过对林隙太阳辐射日变化的动态观测,建立了林隙中不同位置接受辐射总量及光合有效辐射与林冠空隙面积、扩展林隙面积、扩展林隙上方树冠郁闭状况的相关模型.结果表明,在观测时间段内,林隙中心点的总辐射量与光合有效辐射分别为全光照条件的90%及71%;扩展林隙中接受的总辐射及光合有效辐射分别为全光照条件的30%～40%及25%～33%,而林冠下的光照下足全光照的10%.林冠空隙面积40m2或扩展林隙面积110m2的林隙,其光照基本能满足黄山松的生长,林隙更新能够发生.通过人工方法造成适当面积的小块林隙来促使更新发生,可作为风景区黄山松林在维持景观基础上的经营措施.

This paper dealt with the gaps of Huangshan pine( Pinus taiwanensis) forest developed on the meadow of 1400～1600m above sea level of Huangshan Mountain.The method of analyzing annual ring growth of pine trees surrounding gaps was employed to estimate the time of gap formation,which was almost the same as the regeneration occurred there.The dynamic variations of total radiation and photosynthetic available radiation(PAR) at different points in gaps were measured,and a regression model for their estimation based on gap size,expanded gap size and canopy closure situation overhead the extended gap was established.The results indicated that the total radiation and PAR were respectively 90% and 71% of full sunlight in gap center, and 30～40% and 25～33% in expanded gaps,while the light under canopy was less than 10% of full sunlight.In the gaps with an area of 40m\+2 or in the extended gaps with an area of 110m\+2,the light might basically satisfy thegrowth of the pine,and the gap regeneration could occur.It is suggested that man made gaps could be made to facilitate the regeneration of Huangshan pine,which could be used as a management approach for Huangshan pine forests,and also for maintaining the landscape in beauty spots of Huangshan Mountain.