本试验研究了一个林龄序列的巨桉林地枯落物储量、持水量、吸水率、土壤持水性能等与细根生物量关系，结果表明：(1)枯落物现存量在不同林龄林分中表现为5a>6a>2a>4a>1a>3a。不同时期变化趋势为，7-10月凋落量(5.581 t·hm-2)>1-4月凋落量(1.619 t·hm-2)>10-1月的凋落量(0.152 t·hm-2)；(2)枯落物持水量的变异性较大，同一个季节不同林龄林分的枯落物持水量差异显著，1~6a平均持水量分别为：9.8040、12.8218、7.7508、5.9498、17.0042和14.4596 t·hm-2。枯落物吸水率与浸泡时间呈现极显著的相关性(P<0.01)，其季节差异在浸泡的前4~6h表现很明显，一般为秋>冬>夏>春季；林龄差异表现表现为4年生巨桉林枯落物的吸水率最差，1年生的最好；(3)各林龄林分细根生物量在不同季节的基本趋势是：秋>夏>春>冬季(P<0.01)。林龄趋势为：6年生细根生物量最大(0.9063 t·hm-2)，3年生最小(0.5377 t·hm-2)。巨桉幼龄林(1~2a)细根生物量与枯落物持水量及其浸泡时间显著相关，随着林龄的增长，这种关系不明显。%This research studied the biomass, water holding capacity and water absorption of litter and fine roots (<2mm) for an age series of Eucalyptusgrandisrepresenting a complete rotation (ages 1 ~6 years) in Danling, Meishan city of Sichuan province. The results showed: litter reserves differed significantly with age and descended in the following sequence:5-years>6-years>2-years>4-years>1-year>3-years old. The dynamic of litter at different survey times showed the following results:Jul.-Oct. 2006(5.581t·hm-2)>Jan.-Apr. 2007(1.619t·hm-2)>Oct. 2006-Jul. 2007(0.152t·hm-2). Thewater holding capacity of litter was also found to vary with season, as well as at different ages,from 9.804 0 t·hm-2for that of 1-year-old plantation, 12.821 8 t·hm-2for 2-year-old, 7.750 8 t·hm-2 for 3-year-old;5.949 8 t·hm-2 for 4-year-old, 17.004 2 t·hm-2 for 5-year-old, and 14.459 6 t·hm-2 for 6-year-old plantation.It was found that the fastest water absorption occurred during the first 4 hours. After 8 hours water absorption slowed or ceased completely. A significant (P<0.01) relationship was observed between rate of water absorption and immersion time. Seasonal differences were also observed in water absorption during the first 4 hourperiod with seasonal averages descending in the order of autumn >winter>summer>spring. Across different plantation ages, water absorption was lowest at age 4-years and highest at age 1-year. The fine root biomass inthe top 0~50 cmof soil depth (soil core method) varied significantly (P< 0.01) with season in descending order of autumn > summer > winter > spring. The highest fine root biomass was observed in the 6-year oldplantation(0.906 3t·hm-2) andthe lowest in the 3-year old plantation (0.537 7 t·hm-2). There were significant positive correlations between fine root biomass and water holding capacity of litter at age 1 to 2-years but the significance of the correlation decreased as plantation age increased.
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