Impacts of atmospheric nitrogen deposition: responses of multiple plant and soil parameters across contrasting ecosystems in long‐term field experiments

作者：Gareth K. Phoenix, Bridget A. Emmett, Andrea J. Britton, Simon J. M. Caporn, Nancy B. Dise, Rachel Helliwell, Laurence Jones, Jonathan R. Leake, Ian D. Leith, Lucy J. Sheppard, Alwyn Sowerby, Michael Pilkington, E.C. Rowe, M. R. Ashmore, Sally A. Power · 发表于：Global Change Biology · 年份：2011 · DOI：10.1111/j.1365-2486.2011.02590.x · 被引用次数：445 · 研究领域：Peatlands and Wetlands Ecology、Lichen and fungal ecology、Soil Carbon and Nitrogen Dynamics

Abstract Atmospheric nitrogen ( N ) deposition is a global and increasing threat to biodiversity and ecosystem function. Much of our current understanding of N deposition impacts comes from field manipulation studies, although interpretation may need caution where simulations of N deposition (in terms of dose, application rate and N form) have limited realism. Here, we review responses to simulated N deposition from the UKREATE network, a group of nine experimental sites across the UK in a diversity of heathland, grassland, bog and dune ecosystems which include studies with a high level of realism and where many are also the longest running globally on their ecosystem type. Clear responses were seen across the sites with the greatest sensitivity shown in cover and species richness of bryophytes and lichens. Productivity was also increased at sites where N was the limiting nutrient, while flowering also showed high sensitivity, with increases and declines seen in dominant shrub and forb species, respectively. Critically, these parameters were responsive to some of the lowest additional loadings of N (7.7–10 kg ha −1 yr −1 ) showing potential for impacts by deposition rates seen in even remote and ‘unpolluted’ regions of E urope. Other parameters were less sensitive, but nevertheless showed response to higher doses. These included increases in soil % N and ‘plant available’ KCl extractable N , N cycling rates and acid–base status. Furthermore, an analysis of accumulated dose th...