不同密度毛竹林枯落物层水文特性研究

对黄山区4种密度毛竹纯林枯落物层的储量、最大持水量、最大持水率、吸水速率、有效拦蓄量等水文特性参数进行了研究。结果表明:(1)不同密度毛竹林枯落物储量、厚度及自然含水率均存在较大差异;不同林分枯落物储量为3.98 6.00 t·hm-2,其中,以3 000株·hm-2的林分枯落物储量最高。(2)4种密度毛竹林下枯落物最大持水率为317.09%347.58%,密度为3 000株·hm-2时,毛竹林枯落物层最大持水量达到20.70 t·hm-2。(3)4种密度毛竹林枯落物层持水量(S)与浸泡时间(t)的关系为S=alnt+b(a为方程系数,b为方程常数项),其吸水速率(V)与浸泡时间(t)的关系为V=ctd(c为方程系数,d为方程指数);在0 4 h内枯落物吸水速率急剧下降,4 h后明显减缓。(4)密度对毛竹林枯落物水文特性有一定影响,选择适宜的营林密度对于提高毛竹林枯落物层水文生态功能具有重要的作用。

Study on Litter Water Interception Capacity of Phyllostachys edulis Plantations with Different Densities

The litter amount and the water holding characteristic parameters, such as the maximum water holding capacity and rate, the water absorption rate and the modified interception amount of Phyllostachys edulis plantations with four densities were studied in Huangshan district. The results are as follows: The total amount, thickness and natural water content of litters under all the four stands tested were different. The total litter amount in different stands ranged between 3.98 t·hm^-2 to 6.00 t·hm^-2, that in the stand with the density of 3 000 stems·hm^-2 was the most. The ratio of maximum water-holding capacity of litter in various stands ranged from 317.09% to 347.58%. The maximum water holding capacity of litter in the stand with the density of 3 000 stems·hm^-2 was 20.70 t·hm^-2. By analyzing, the relationship between the water holding capacity of litter and the immersion time followed the equation of: W=alnt+b (a is the coefficient; b is the constant term). The relationship between the water absorption speed of the litter and the immerse time followed the equation of: V=ct^d (c is the coefficient; d is the exponential term). The litter water capacity increased rapidly within the first four hours, and then increased slowly. The results also showed that the hydrological character of litter was positively related to density in Ph. edulis forest. Therefore, it is important to choose appropriate density for enhancing the eco-hydrological benefits of litter layer in Ph. edulis forest.