期刊
SOIL BIOLOGY & BIOCHEMISTRY
卷 34, 期 3, 页码 373-385出版社
PERGAMON-ELSEVIER SCIENCE LTD
DOI: 10.1016/S0038-0717(01)00195-X
关键词
Alnus incana; Betula sp; boreal; forest soil; nitrification; nitrogen mineralisation; Picea abies
类别
We monitored net and gross N transformations in the organic layer along a primary successional transect (alder/rowan, birch, birch/spruce, spruce I and spruce II) typical for the land-uplift coast in Western Finland. The relationships between N transformations, vegetation succession and organic matter quality (i.e. concentration of dissolved forms of N, C/N ratio, moisture and acidity) were then evaluated. Net N mineralisation rates in the organic layer were estimated in 5-week incubation experiments in situ using intact soil cores, and in the laboratory on sieved, fresh organic layer samples. Microbial biomass N (fumigation-extraction) and gross N mineralisation (N-15-isotope dilution method), were determined once in the laboratory. The C/N ratio increased and pH and net N mineralisation decreased in the organic layer along the succession transect. The alder/rowan site was the only site to show net nitrification. Microbial biomass N tended to increase along the transect from the alder/rowan site to spruce I, and decreased again in spruce II. Concurrently, gross N mineralisation showed a tentative increasing trend along the transect, although the differences between the sites were non-significant. The higher net N mineralisation rates in the alder/rowan site compared to the spruce sites were thus due to lower microbial immobilisation rather than to greater gross N mineralisation. Possible methodological reasons for the lack of response of gross N mineralisation rate to decreasing soil organic matter quality are discussed. (C) 2002 Elsevier Science Ltd. All rights reserved.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据