对福建三明莘口教学林场不同发育阶段杉木人工林进行凋落物现存量、持水特性及失水特性研究。结果表明:不同发育阶段杉木人工林凋落物的现存量表现为老龄林(3.47t/hm2)〉中龄林(2.24t/hm2)〉幼龄林(1.53t/hm2)。凋落物持水量表现为老龄林〉中龄林〉幼龄林;最大持水量表现为老龄林(11.8t/hm2)〉中龄林(7.73t/hm2)〉幼龄林(4.24t/hm2);最大持水率表现为中龄林(477.48%)〉幼龄林(376.57%)〉老龄林(291.98%);最大失水量表现为老龄林(4.29t/hm2)〉中龄林(2.91t/hm2)〉幼龄林(1.71t/hm2);最大失水率表现为中龄林(129.90%)〉老龄林(124.15%)〉幼龄林(112.04%)。凋落物层吸水速率均表现在前0.5h内最快,说明凋落物层具有快速拦截地表径流的作用。凋落物的持水量、持水率、失水量、失水率与时间之间的最佳拟合关系式为W=a+bln t;吸水速率、失水速率与时间之间的最佳拟合关系式为V=atb。老林龄杉木凋落物层具有现存量大、持水量大、吸水速率强等特点,具有较强的生态水文功能。
This paper deals with the litterfall production,water-holding character,and water-losing character in different developing stages of Chinese fir.The results were as follows: The dry litter production was in the sequence of mature forest(3.47 t/hm2) middle forest(2.24 t/hm2) young forest(1.53 t/hm2).The order of water-holding capacity was the same as the litterfall production,and the maximum water-holding capacity was 11.8 t/hm2,7.73 t/hm2,4.24 t/hm2 correspondingly.The proportional water holding capacity as a percentage of the litter dry weight in middle forest,young forest,and mature forest were 477.48%,376.57%,and 291.98%,respectively.The maximum water-losing capacity were in the same sequence as water-holding capacity,the corresponding amounts were 4.29 t/hm2,2.91 t/hm2,and 1.71 t/hm2.The maximum water-losing rate were as the follows: Middle forest(129.90%) mature forest(124.15%) young forest(112.04%).The litter layer could intercept surface runoff rapidly,because the water absorption rate was fastest during 0.5 hour.Water-holding capacity,water-holding rate,water-losing capacity,and water-losing rate of litterfall increased according to W=a+bln t with the time increasing immersed in water,and the equation of water absorption rate and water-losing rate was V=atb.In sum,the litter layer of mature Chinese fir had strong ecological hydrological function due to the bigger litterfall production,higher water-holding capacity and faster water absorption rate.