A new species index for forest vascular plants: development of functional indices based on mineralization rates of various forms of soil nitrogen

作者：Martin Diekmann, Ursula Falkengren‐Grerup · 发表于：Journal of Ecology · 年份：1998 · DOI：10.1046/j.1365-2745.1998.00250.x · 被引用次数：113 · 研究领域：Soil Carbon and Nitrogen Dynamics、Botany and Plant Ecology Studies、Peatlands and Wetlands Ecology

1 Soil nitrogen mineralization rates for ammonium, nitrate and total‐N were determined by incubation experiments for 661 sample plots of deciduous forest from different regions in southern Sweden. 2 Species N indices for nitrate and ammonium were calculated as the weighted averages of mineralized N in those plots where the species were present. 3 Optimized linear models were used to combine mineralization rates for NH + 4 + NO minus; 3 to produce a functional N index for plots (FNIP) and to combine the species indices for NH + 4 + NO minus; 3 to produce a functional N index for species (FNIS). 4 The sample scores along the first axis of a detrended correspondence analysis (DCA) were highly correlated with soil acidity and mineralized ammonium, whereas total‐mineralized N accounted for most of the variation along the second DCA axis. The species scores along the first axis were highly correlated with the ammonium index. 5 FNIP was somewhat better correlated with the sample scores along axis 1 than mineralized ammonium, but only slightly better correlated than total‐mineralized N relative to axis 2. Similar results were obtained for FNIS. 6 Ammonium index and FNIS explained more of the floristic variation along the ordination axes than Ellenberg's N indicator values. Weighted averages of these indices also showed higher correlations with the sample scores along the axes than corresponding averages of Ellenberg's N values. However, when ammonium index and FNIS for the most frequ...