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研究了川西亚高山云杉人工林和天然林养分的分布和生物循环特点 ,结果表明 :云杉天然林和人工林各养分含量变化总趋势为 :w(N) ,针叶 >凋落物 >土壤 >树枝 >树干 ;w(P2 O5,K2 O ,CaO ,MgO) ,土壤 >凋落物 >针叶 >树枝 >树干 ;在针叶、树枝、树干和凋落物中养分含量是CaO >N >K2 O >MgO >P2 O5,而在土壤中养分含量是CaO >K2 O >MgO >N >P2 O5.养分贮量以天然云杉林最高 ,且主要集中在土壤中 (占 6 9%) ,而人工云杉林随着抚育林龄的增加 ,地上各组分养分贮量增加 ,土壤中养分贮量则先升后降 ,人工和天然云杉林地上各组分养分贮量主要集中在针叶 ;云杉林养分年积累量以天然林最高 ,在人工林中随着抚育林龄的增加 ,养分年积累量随之增加 ,人工云杉幼林以N、CaO积累为主 ,而成熟林则以CaO、N积累为主 .养分的吸收、存留量天然林高于人工云杉林 ,人工云杉成熟林和天然林的利用系数和周转期相似 ,人工云杉林随着抚育林龄的增加 ,吸收、存留量增大 ,利用系数降低 ,归还量和循环系数先增后降 ,周转期则变长 ,人工云杉林利用系数顺序为 :CaO >MgO >N >K2 O >P2 O5,周转期顺序为 :P2 O5>K2 O >MgO >N >CaO .表 5参 14
The distribution and biocirculation characteristics of subalpine spruce plantations and natural forests in western Sichuan were studied. The results showed that the general trend of nutrient contents of natural spruce and plantation was w (N), conifer> litter> soil > Tree branches> tree roots; w (P2 O5, K2 O, CaO, MgO), soil> litter> needles> branches> tree trunks; nutrient contents of conifer, branch, trunk and litter were CaO> N> > MgO> P2 O5, while the content of nutrients in the soil is CaO> K2 O> MgO> N> P2 O5. The nutrient storage is the highest in natural spruce forest and mainly in the soil (69%), The spruce forest increased with the increase of tending age, the nutrient storage of each component on the ground increased, while the nutrient storage in soil increased first and then decreased. The nutrient storage of each component in the artificial and natural spruce forest mainly concentrated in the coniferous forest. The annual accumulation of nutrients in spruce forest was the highest in natural forests. With the increase of tending age, the accumulation of nutrients in the spruce forest increased with the increase of N and CaO accumulation, while that of mature spruce forests was CaO , N accumulation.The absorption and storage of nutrients in natural forests were higher than those in artificial spruce, artificial mature spruce and natural forest Similar to the turnover period, with the increase of tending age, the absorption and storage of artificial spruce forest increased, the utilization coefficient decreased, the return and circulation coefficient increased first and then decreased, and the turnover period became longer. The utilization coefficient of artificial spruce forest The order is: CaO> MgO> N> K2O> P2 O5, the order of turnover is: P2 O5> K2 O> MgO> N> CaO.