Different fates of deposited NH4+ and NO3− in a temperate forest in northeast China: a 15N tracer study. (10th November 2016)

• Record Type: Journal Article
• Authors: Liu, Jun; Peng, Bo; Xia, Zongwei; Sun, Jianfei; Gao, Decai; Dai, Weiwei; Jiang, Ping; Bai, Edith
• Is Part Of: Global change biology. Volume 23:Number 6(2017)
• Page Start: 2441
• Page End: 2449
• Publication Date: 2016-11-10
• Subjects: broad‐leaved and Korean pine (Pinus koraiensis) mixed forest -- nitrogen deposition -- nitrogen fate -- nitrogen retention -- nitrogen saturation; Climatic changes -- Environmental aspects -- Periodicals; Troposphere -- Environmental aspects -- Periodicals; Biodiversity conservation -- Periodicals; Eutrophication -- Periodicals; 551.5
• DOI: 10.1111/gcb.13533
• Languages: English
• ISSNs: 1354-1013

Abstract

Abstract: Increasing atmospheric reactive nitrogen (N) deposition due to human activities could change N cycling in terrestrial ecosystems. However, the differences between the fates of deposited NH 4 + and NO 3 − are still not fully understood. Here, we investigated the fates of deposited NH 4 + and NO 3 −, respectively, via the application of 15 NH4 NO3 and NH4 15 NO3 in a temperate forest ecosystem. Results showed that at 410 days after tracer application, most 15 NH 4 + was immobilized in litter layer (50 ± 2%), while a considerable amount of 15 NO 3 − penetrated into 0–5 cm mineral soil (42 ± 2%), indicating that litter layer and 0–5 cm mineral soil were the major N sinks of NH 4 + and NO 3 −, respectively. Broad‐leaved trees assimilated more 15 N under NH4 15 NO3 treatment compared to under 15 NH4 NO3 treatment, indicating their preference for NO 3 − –N. At 410 days after tracer application, 16 ± 4% added 15 N was found in aboveground biomass under 15 NO 3 − treatment, which was twice more than that under 15 NH 4 + treatment (6 ± 1%). At the same time, approximately 80% added 15 N was recovered in soil and plants under both treatments, which suggested that this forest had high potential for retention of deposited N. These results provided evidence that there were great differences between the fates of deposited NH 4 + and NO 3 −, which could help us better understand the mechanisms and capability of forest ecosystems as a sink of reactive nitrogen.