Topographical Differences in Soil N Transformation Using ^<15>N Dilution Method along a Slope in a Conifer Plantation Forest in Japan :
-
- Tokuchi,Naoko
- Laboratory of Forest Ecology, Kyoto University
-
- Hirobe,Muneto
- Laboratory of Forest Ecology, Kyoto University
-
- Koba,Keisuke
- Laboratory of Forest Ecology, Kyoto University
この論文をさがす
抄録
Soil N transformation was investigated using ^<15>N dilution method along a slope on a conifer plantation forest. Although there was no significant difference in the net N mineralization rates by laboratory incubation, net nitrification rates increased downslope. Gross N transformation by ^<15>N dilution method showed a distinct difference not only on the rates, but also on the main process between the lower and the upper of the slope. Half of minelarized N was immobilized and the other half was left in NH_4^+ pool at the upper part of the slope, while all of mineralized N was used for immobilization or nitrification and NH_4^+ pool decreased at the lower of the slope. Soil N transformations were classified into two groups : one was shown below 773 m and the other was shown above 782 m. The incubation with nitrification inhibitor showed that nitrification was mainly conducted by autotrophs irrespective of the position of the slope. Microbial biomass and microbial C/N were similar among the sites. However, the gross mineralization rate was higher below 773 m than above 782 m under similar respiration rates. This suggests that the substrate quality may be one of the controlling factors for soil N transformation. Extractable organic C/N was similar to microbial C/N at the lower of the slope. It indicated that the substrate was more decomposable below 773 m. It is considered that soil N transformation is affected by topographical gradient of moisture and nutrient which makes plant growth and decomposition rate different.
収録刊行物
-
- Journal of forest research
-
Journal of forest research 5 (1), 13-19, 2000-02-16
Japanese Forestry Society
- Tweet
詳細情報 詳細情報について
-
- CRID
- 1541417145291485312
-
- NII論文ID
- 110002694509
-
- NII書誌ID
- AA11074682
-
- 本文言語コード
- en
-
- データソース種別
-
- NDL-Digital
- CiNii Articles