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2014—2015年,采用野外实地观测与人工降水试验法,对甘肃兴隆山天然青杄纯林和山杨—白桦—青杄混交林的苔藓和凋落物自然含水量动态、苔藓及凋落物持水性能与降水因子关系进行了研究。结果表明:(1)山杨—白桦—青杄混交林和青杄纯林苔藓生物量分别0.30t/hm~2和1.83t/hm~2;凋落物蓄积量分别为57.08t/hm~2和51.44t/hm~2;凋落物层在森林地被物中具有十分重要的位置,而苔藓层为次要位置;(2)青杄林苔藓、凋落物自然含水量月动态变化较大,但凋落物层变化明显滞后于苔藓层;苔藓、凋落物层自然含水量变化与当地降水量成正相关性,其含水量4—6月较小,7—8月较高;苔藓、凋落物层自然含水量最小值依次为10%和25%,最大依次为125%和115%;(3)在降水过程中,森林苔藓及凋落物吸持降水是一个十分缓慢的过程;只有在小强度、长历时降水条件下,才有可能使森林苔藓及凋落物层吸持水量达到饱和状态。
In 2014-2015, field experiments and artificial rainfall experiments were conducted to study the dynamic changes of natural moisture content of moss and litter in the natural forests of P. xinchuensis and Populus tomentosa - Betula platyphylla - mixed forest in Xinglong Mountain, Gansu Province. Performance and precipitation factors were studied. The results showed that: (1) The moss biomass of aspen - birch - mulberry mixed forest and mulberry pure forest were 0.30 t / hm ~ 2 and 1.83 t / hm ~ 2, respectively, and the litter volume was 57.08 t / hm ~ 2 And 51.44 t / hm ~ 2 respectively. The litter layer was very important in the forest land cover, while the moss layer was the secondary site. (2) The monthly variation of natural water content of moss and litter in the forest had a great dynamic change, However, the variation of litter layer obviously lags behind that of the moss layer. The changes of natural moisture content of moss and litter layer have a positive correlation with the precipitation, the water content is small from April to June and higher from July to August. The moss, litter layer The minimum natural water content was 10% and 25% in turn followed by 125% and 115%, respectively. (3) During the precipitation, forest moss and litterfalls were a very slow process. Only in the low intensity, Under long-term precipitation conditions, it is possible to make forest moss and litter layer to absorb water saturation.