Ecosystem recovery after a decrease in nitrogen input to a Scots pine stand at Ysselsteyn, the Netherlands
Ecosystem recovery after a decrease in nitrogen input to a Scots pine stand at Ysselsteyn, the Netherlands
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DOI：
10.1016/s0378-1127(97)00132-1
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发表时间：
1998-02-01
影响因子：
3.7
通讯作者：
Roelefs, JGM
中科院分区：
文献类型：
--
作者：
Boxman, AW;van der Ven, PJM;Roelefs, JGM
在一个高度N饱和的苏格兰松立场大气氮输入到森林地面减少到工业化前的水平，通过一个透明的屋顶和应用程序的清洁，人工穿透水。氮输入从每年约60公斤氮公顷减少到每年< 5公斤氮公顷。该实验始于1989年，是NITREX？项目目的是评估氮饱和的可逆性。结果表明，氮素投入与产出之间存在着密切的相关关系。这种反应的时间是快速的，而植被的反应滞后了几年。在这一滞后阶段之后，人们注意到了生态系统恢复的迹象。针叶中N浓度下降，营养平衡得到改善。针叶中的游离甜菜碱-N浓度可以指示树对N输入变化的响应。虽然针叶中的总氮浓度仍然很高，但甜菜碱氮浓度的迅速下降可能是恢复的第一个迹象。树木的反应与增长的改善，这是显着相关的降低甜菜碱-N浓度。在实验期间，喜氮植物地上生物量明显下降，而菌根真菌子实体的重新定殖和增加。(C)1998年Elsevier Science B.V.
In a highly N-saturated Scots pine stand atmospheric N input to the forest floor was reduced to pre-industrial levels by means of a transparent roof and application of clean, artificial throughfall water. The N input was reduced from approximate to 60 kg N ha(-1) yr(-1) to < 5 kg N ha(-1) yr(-1). The experiment began in 1989 and is part of the NITREX? project. The aim is to assess the reversibility of N saturation. The results showed a close correlation between the input and output of N. The timing of this response is fast in contrast to the vegetation response which lags for some years. After this lag-phase signs of ecosystem recovery were noticed. The N concentration in the needles declined and the nutritional balance improved. Free arginine-N concentrations in the needles may be indicative of tree response to changes in N input. Although the total-N concentration in the needles is still high, the rapid drop in arginine-N concentrations may be the first sign of recovery. The trees have reacted with a growth improvement which is significantly correlated to decreasing arginine-N concentrations. The above-ground biomass of the nitrophilous ground vegetation decreased markedly during the experimental period, whilst there was a re-colonization and increase of fruitbodies of mycorrhizal fungi. (C) 1998 Elsevier Science B.V.