武陵山区小流域不同年龄结构杜仲人工林生物量研究

Biomasses of Eucommia ulmoides plantations with different age structures at small watershed of Wuling Mountain Region

为给杜仲林的经营管理提供科学依据,采用收获法,以武陵山区小流域不同年龄结构杜仲人工林作为研究对象,对其生物量进行研究。结果表明:在立地条件基本相同的情况下,杜仲人工林生物量随年龄增大而增加。27年生杜仲人工林单株生物量显著高于5年生杜仲人工林,单株各器官按照生物量由高到低排序均为干、根、枝、皮、叶;在林分生物量组成中,乔木层所占比例最大(74.04%),枯落物层次之(15.92%)。27年生杜仲人工林乔木层生物量为510 741.82 kg/hm2,明显高出5年生杜仲人工林;27年生杜仲人工林年平均净生产力为26 782.13 kg/(hm2·a),高于其它年龄段杜仲人工林,在各林分中以树干的净生产力最高,树皮最低。

In order to offer a scientific basis for operating and management of Eucommia ulmoides forest, biomasses of the E. ulmoides plantations with different age structures at small watershed of Wuling Mountain Region were studied by using harvest method. The results showed that in the basically same site conditions, biomasses of E. ulmoides plantations were increased with age. Biomass of single 27-year-old plant in E. ulmoides plantations was significantly higher than that of single 5-year-old plant. The order of different organs based on single plant biomass from high to low was stem, root, branch, peel, leaf. In the case of stand biomass composition, tree layer accounted for the largest proportion, and litter layer was the second. Biomass of tree layer in E. ulmoides plantations at 27 years old was 510 741.82 kg/hm2, which was obviously higher than that in E. ulmoides plantations at 5 years old. Annual average net production of E. ulmoides plantations at 27 years old was 26 782.13 kg/（hm2＆#183;a）, which was higher than the plantations at the other age stages. Net production of stem was the highest, and that of bark was the lowest.