内蒙古土石山区油松林枯落物层水文生态功能研究

为探究林分密度对土石山区油松林枯落物持水特性的影响,以内蒙古大青山南坡4种不同林分密度的油松林为研究对象,通过样地调查与室内浸水实验相结合的方法,对其枯落物蓄积量以及持水特性等进行研究。结果表明:(1)4种不同密度油松人工林枯落物层厚度范围为1.94~3.85 cm,枯落物储量范围为8.49~19.94 t·hm^-2,厚度与储量均随着林分密度的增大而增大;(2)4种不同密度油松人工林枯落物最大持水量范围为23.82~45.81 t·hm^-2,大小顺序为2564株·hm^-2>3189株·hm^-2>1828株·hm^-2>1473株·hm^-2;最大持水率范围为225.11%~287.16%,大小依次为1473株·hm^-2>1828株·hm^-2>2564株·hm^-2>3189株·hm^-2;(3)不同林分密度枯落物持水量与浸水时间呈对数函数关系:W=aln(t)+b;枯落物持水速率与浸水时间呈幂函数关系:V=ktn。综上所述,密度为2564株·hm^-2的油松林,其枯落物持水特性表现最好,水源涵养能力最强,建议在相似立地条件下,油松林营建应向此范围调控。

Study on Hydrological and Ecological Functions of Litters in Pinus tabulaeformis Plantation in Earth-rocky Mountains Area of Inner Mongolia

The purpose of this study is to investigate the effect of stand density on water-holding characteristics of litters in Pinus tabulaeformis plantation,this paper studies Pinus tabulaeformis plantation with four different stand densities on the south slope of Daqing Mountains in Inner Mongolia.Through the method of plots survey and indoor immersion experiment,the volume and water-holding characteristics of litters has been studied.The results show that:(1)The litters thickness of four Pinus tabulaeformis plantation with different densities ranged from 1.94 to 3.85 cm,and the volume ranged from 8.49 to 19.94 t·hm^-2.The thickness and volume increased with the increase of stand density.(2)The maximum water-holding capacity of litters in Pinus tabulaeformis plantation with four different densities ranged from 23.82 to 45.81 t·hm^-2,the order of maximum water-holding capacity was 2564 stocks·hm^-2>3189 stocks·hm^-2>1828 stocks·hm^-2>1473 stocks·hm^-2.The maximum water-holding rate ranged from 225.11%to 287.16%,and the order was 1473 stocks·hm^-2>1828 stocks·hm^-2>2564 stocks·hm^-2>3189 stocks·hm^-2.(3)The relationship between the moisture capacity of litters with different stand densities and the soaking time was logarithmic function:W=aln(t)+b.There was a power function relationship between the water holding rate and the soaking time:V=ktn.In conclusion,Pinus tabulaeformis plantation with a density of 2564 stocks·hm^-2 had the best water-holding characteristics of litters and the strongest water-conservation capacity.It is suggested that with similar site conditions,the construction of Pinus tabulaeformis plantation should be regulated to this density.