三种高寒草甸植被分布及与湍流交换通量关系的比较

对海北定位站分布的金露梅灌丛草甸、矮嵩草草甸、藏嵩草沼泽化草甸3种高寒植被类型群落结构、感热(H)和潜热(LE)通量比较观测表明,3种植被类型年地上净初级生产力表现出矮嵩草草甸(318.600g/m2)>藏嵩草沼泽化草甸(258.341g/m2)>金露梅灌丛草甸(217.695g/m2)。植物种类组成有矮嵩草草甸(54种)>金露梅灌丛草甸(47种)>沼泽草甸(24种)。3种植被类型区近地表大气能量交换过程中,LE和H的月际变化明显,而且随植被类型的不同月际变化差异显著。3种不同植被类型在年内均表现出H LE>0,表明在青海海北高寒草甸地区,太阳辐射强烈,近地层湍流输送明显,地表为一热源。3类型高寒草甸植被的年地上净生产量基本与波文比(β)呈现正效应,与LE H呈现明显的反效应。植物种类组成基本与LE H有反效应,与β呈明显的正效应。

The Distribution of Three Kinds of Different Alpine Meadow Vegetation and the Comparison of the Vegetation with Sensible Heat and Latent Heat Flux

The comparison of Potentilla froticosa shrub meadow,Kobresia humlis meadow and Kobresia tibetica of swamp meadow with Sensible heat and Latent heat flux was studied in Haibei Station.The annual primary productivity of three vegetation types showed that Kobresia humlis meadow(318.6 g/m2)> Kobresia tibetica of swamp meadow(258.341 g/m2)> Potentilla froticosa shrub meadow(217.695 g/m2).As to vegetation composition,the results showed Kobresia humlis meadow(54)> Potentilla froticosa shrub meadow(47)> Kobresia tibetica of swamp meadow(24).The monthly changes of Sensible heat and Latent heat were significant(P<0.05)in the atmospheric energy exchange process in the ground level of three different vegetation types.The annual results of three vegetation types showed that H LE > 0.It is showed that in Haibei alpine area solar radiation is strong,the flux is obvious in ground level and the ground is one of heat source.The annual ground biomass of three types of alpine vegetation has a positive relationship with Bowen ratio,and had a strong negative relationship with H LE.However,the composition of vegetation had a negative relationship with H LE,and positive relationship with Bowen ratio.