106 research outputs found
Effects of beech (Fagus sylvatica), ash (Fraxinus excelsior) and lime (Tilia spec.) on soil chemical properties in a mixed deciduous forest
Foliar δ15N values characterize soil N cycling and reflect nitrate or ammonium preference of plants along a temperate grassland gradient
The natural abundance of stable 15N isotopes in soils and plants is potentially a simple tool to assess ecosystem N dynamics. Several open questions remain, however, in particular regarding the mechanisms driving the variability of foliar δ15N values of non-N2 fixing plants within and across ecosystems. The goal of the work presented here was therefore to: (1) characterize the relationship between soil net mineralization and variability of foliar Îδ15N (δ15Nleaf â δ15Nsoil) values from 20 different plant species within and across 18 grassland sites; (2) to determine in situ if a plantâs preference for NO3â or NH4+ uptake explains variability in foliar Îδ15N among different plant species within an ecosystem; and (3) test if variability in foliar Îδ15N among species or functional group is consistent across 18 grassland sites. Îδ15N values of the 20 different plant species were positively related to soil net mineralization rates across the 18 sites. We found that within a site, foliar Îδ15N values increased with the speciesâ NO3â to NH4+ uptake ratios. Interestingly, the slope of this relationship differed in direction from previously published studies. Finally, the variability in foliar Îδ15N values among species was not consistent across 18 grassland sites but was significantly influenced by N mineralization rates and the abundance of a particular species in a site. Our findings improve the mechanistic understanding of the commonly observed variability in foliar Îδ15N among different plant species. In particular we were able to show that within a site, foliar δ15N values nicely reflect a plantâs N source but that the direction of the relationship between NO3â to NH4+ uptake and foliar Îδ15N values is not universal. Using a large set of data, our study highlights that foliar Îδ15N values are valuable tools to assess plant N uptake patterns and to characterize the soil N cycle across different ecosystems
Effects of litters with different concentrations of phenolics on the competition between Calluna vulgaris and Deschampsia flexuosa
The effect of nutrient supply and light intensity on tannins and mycorrhizal colonisation in Dutch heathland ecosystems
Foliar and soil 15N natural abundances provide field evidence on nitrogen dynamics in temperate and boreal forest ecosystems
Distribution of field layer species in Swedish deciduous forests in 1929-54 and 1979-88 as related to soil pH
Application of two soil acidification models to historical soil chemistry data from Sweden
Changes of cation pools of the topsoil in south Swedish beech forests between 1979 and 1989
Cover distributions of vascular plants in relation to soil chemistry and soil depth in a granite rock ecosystem
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