Soil samples were taken from an Ermans birch(Betula ermanii)-dark coniferous forest(Picea jezoensis and Abies nephrolepis)ecotone growing on volcanic ejecta in the northern slope of Changbai Mountains of Northeast Chi...Soil samples were taken from an Ermans birch(Betula ermanii)-dark coniferous forest(Picea jezoensis and Abies nephrolepis)ecotone growing on volcanic ejecta in the northern slope of Changbai Mountains of Northeast China,to compare soil carbon(C)and nitrogen(N)transformations in the two forests.The soil type is Umbri-Gelic Cambosols in Chinese Soil Taxonomy.Soil samples were incubated aerobically at 20-C and field capacity of 700 g kg-1 over a period of 27 weeks.The amount of soil microbial biomass and net N mineralization were higher in the Ermans birch than the dark coniferous forest(P<0.05),whereas the cumulative C mineralization(as CO2 emission)in the dark coniferous forest exceeded that in the Ermans birch(P<0.05).Release of the cumulative dissolved organic C and dissolved organic N were greater in the Ermans birch than the dark coniferous forest(P<0.05).The results suggested that differences of forest types could result in considerable change in soil C and N transformations.展开更多
基金Project supported by the National Natural Science Foundation of China(No.90411020)the National Key Basic Research Program(973 Program)of China(No.2002CB412502)
文摘Soil samples were taken from an Ermans birch(Betula ermanii)-dark coniferous forest(Picea jezoensis and Abies nephrolepis)ecotone growing on volcanic ejecta in the northern slope of Changbai Mountains of Northeast China,to compare soil carbon(C)and nitrogen(N)transformations in the two forests.The soil type is Umbri-Gelic Cambosols in Chinese Soil Taxonomy.Soil samples were incubated aerobically at 20-C and field capacity of 700 g kg-1 over a period of 27 weeks.The amount of soil microbial biomass and net N mineralization were higher in the Ermans birch than the dark coniferous forest(P<0.05),whereas the cumulative C mineralization(as CO2 emission)in the dark coniferous forest exceeded that in the Ermans birch(P<0.05).Release of the cumulative dissolved organic C and dissolved organic N were greater in the Ermans birch than the dark coniferous forest(P<0.05).The results suggested that differences of forest types could result in considerable change in soil C and N transformations.
基金Project supported by the Knowledge Innovation Project of the Chinese Academy of Sciences (No.KZCX2-YW-416)National NaturM Science Foundation of China (No.90411020)
文摘这研究的目的是调查更高的 CO2 集中的效果(500 和 700 μ m ol 摩尔 ? 1 ) 在全部的土壤呼吸和到全部的土壤呼吸的根呼吸的贡献上的空气在 Pinus sylvestris var 的幼苗生长期间。sylvestriformis。在从 1999 ～ 2003 的四生长期(5 月 10 月) 期间，幼苗在开顶的房间暴露于 CO2 的提高的集中。根呼吸的全部的土壤呼吸和贡献在 6 月 15 日用一个 LI-6400-09 土壤 CO2 流动房间被测量并且 2003 年 10 月 8 日。到从全部的土壤呼吸的分开的根呼吸，三 PVC 柱体被插入进在每个房间的土壤约 30 厘米深。有显著日报在 6 月 15 日在空和土壤温度中变化。没有根的全部的土壤呼吸和土壤呼吸出现了一强壮日报模式，在下午从以前增加日出到大约 14:00 然后在下一日出前减少。有切断的根的吝啬的全部的土壤呼吸和吝啬的土壤呼吸的增加都没在 2003 年 6 月 15 日在提高的 CO2 处理下面被观察，作为与有周围的 CO2 的田野和控制房间相比。在 2003 年 10 月 8 日，然而，有根的全部的土壤呼吸和土壤呼吸在田野切断了是比在控制的那些低的并且提高了 CO2 房间。在 2003 年 6 月 15 日测量的根呼吸的吝啬的贡献，从 8.3% ～ 30.5% 并且在 2003 年 10 月 8 日，从 20.6% ～ 48.6% 。
基金This project was supported by the Knowledge Innovation Project from Chinese Academy （KZCXI-SW-01） and the National Natural Science Foundation of China （30070158）.
基金The study was supported by Major State Basic Research Development Program of China (2002CB412502) and the Knowledge Inno-vation Project from Chinese Academy of Sciences (KZCX1-SW-01-03).
