飞播马尾松林水源涵养功能特征

Characteristics of water conservation capacity of aerially seeded Pinus massoniana plantation

以江西省兴国县为研究区,基于2019年森林资源二类调查数据,采用综合蓄水能力法对飞播马尾松林水源涵养功能进行估算,并比较不同密度、坡位、坡向和海拔条件下林分水源涵养功能的差异。结果表明:(1)飞播马尾松林单位面积水源涵养量为719.53 t·hm^(-2),其中,土壤层、枯枝落叶层和林冠层单位面积水源涵养量分别为387.40 t·hm^(-2)、7.06 t·hm^(-2)和325.07 t·hm^(-2)。(2)低密度(<1500株·hm^(-2))、中密度(1500~2100株·hm^(-2))、高密度(≥2100株·hm^(-2))林分单位面积水源涵养量分别为582.32 t·hm^(-2)、858.65 t·hm^(-2)和835.87 t·hm^(-2)。(3)不同坡位、坡向、海拔的林分单位面积水源涵养量存在一定的差异,中坡的单位面积水源涵养量显著大于上坡(P<0.05);从坡向看,阴坡的单位面积水源涵养量最小(640.28 t·hm^(-2)),半阳坡的最大(717.03 t·hm^(-2));随着海拔的升高,单位面积水源涵养量呈现先增加后减少的趋势。同时,不同坡位、坡向、海拔林分的单位面积林冠截留降水量、枯枝落叶层持水量、土壤层蓄水量之间表现出的差异性不尽相同。土壤层蓄水量是林分水源涵养量的主体,通过调节林分密度能有效提高飞播马尾松林的水源涵养能力。

Taking Xingguo County of Jiangxi Province as the study area,based on the forest resource inventory data in 2019,the water conservation function of a aerially seeded P.massoniana plantation was estimated by the comprehensive water storage capacity method.The difference of stand water conservation function in different stand density,slope position,slope aspect and altitude were compared.The results showed that:(1)The water conservation of aerially seeded P.massoniana plantation was 719.53 t·hm^(-2).The water conservation of soil,litter and canopy layers were 387.40 t·hm^(-2),7.06 t·hm^(-2) and 325.07 t·hm^(-2),respectively.(2)The water conservation of low density(<1500 trees·hm^(-2)),medium density(1500~2100 trees·hm^(-2))and high density(≥2100 trees·hm^(-2))stands were 582.32 t·hm^(-2),858.65 t·hm^(-2) and 835.87 t·hm^(-2),respectively.(3)There were some differences in stand water conservation with different slope position,slope aspect and altitude.The stand water conservation of the middle slope was significantly greater than that of the upper slope(P<0.05).The strand water conservation of the shady slope was the smallest(640.28 t·hm^(-2)),and that of the semi-sunny slope was the largest(717.03 t·hm^(-2)).The stand water conservation increased first and then decreased with the increase of altitude.The differences of canopy interception precipitation,litter holding capacity and soil layer water storage were different in different slope position,slope aspect and altitude.The water storage of soil layer is the main body of water conservation of stand.The water conservation capacity of aerially seeded P.massoniana plantation can be effectively improved by adjusting the stand density.