A trait‐based analysis of the role of phosphorus vs. nitrogen enrichment in plant species loss across North‐west European grasslands

Abstract

Summary1. Both nitrogen (N) and phosphorus (P) enrichment have been identified to drive plant species losses from nutrient-poor semi-natural grasslands. The relative contribution of N vs. P to species loss remains unclear, however. 2. We investigated how soil N and P availability affect the occurrence of 61 grassland species across North-western Europe. We selected 132 study sites, located in Great Britain, Belgium and France, along a soil fertility gradient based on variability in atmospheric N deposition and on nutrient input from adjacent agricultural land. To gain insight into the underlying ecological mechanisms of species loss, we examined the role of a suite of plant traits that may mediate a species' response to increased N or P availability. 3. Mixed logistic regression showed that the occurrence of 24 plant species (39AE3%) was affected by soil nutrient availability. Of these species, 18 were negatively affected by increased P (29AE5%) and five by increased N (8AE2%). Regionally declining plant species were absent from both P-rich and N-rich grasslands. Higher susceptibility to elevated P was associated with stress tolerance, low maximum canopy height and symbiosis with arbuscular mycorrhizae. 4. Synthesis and applications. Although we also identified negative effects on plant diversity through N enrichment, our results strongly suggest that P enrichment is a more important driver of species loss from semi-natural grasslands. Species in symbiosis with mycorrhizae and with low canopy height are especially at risk. Because detrimental effects of P enrichment are very difficult to mitigate due to the persistence of P in the soil, nature management should give absolute priority to preventing P input in grasslands through fertilization, agricultural run-off or inundation with P-polluted surface water. To restore species-rich grasslands on P-enriched soils, top soil removal appears crucial and more research regarding alternative removal strategies is essential.

Distribution patterns of arbuscular mycorrhizal and non-mycorrhizal plant species in Germany

“…Other predictors such as precipitation or temperature, which lead to different agricultural practices, may overrule the effects of those practices at the scale analysed. The same is true for spatial distributions of nitrogen and phosphorus availability, which influence the composition of plants and their AM status and are influenced by fertilisation regimes (Ceulemans et al, 2011;Landis et al, 2004). Within our grid system of cells with c. 130km², it is not possible to accurately map differences in nutrient availability, which act on a far finer scale.…”

Application of Manure and Phosphorus Bio-Solubilizers with Rock Phosphate in Calcareous Soils to Increase Phosphorus Availability and Productivity of Safflower Plant

“…Application of antioxidants can alleviate the adverse effect of salinity (Farouk, 2011). Phosphorus could be involved in such alleviation and presence of enough P in the rhizosphere can augment plant resistance to salinity (Ceulemans et al, 2011 andLambers et al, 2014).…”

Classification of Grassland Successional Stages Using Airborne Hyperspectral Imagery

“…[83]). The effects of the addition of nutrients during arable cultivation may persist during the early stages of the arable-to-grassland succession [84,85]. Recently cultivated fields, such as the young grasslands in our study ( Figure 5A), are generally characterized by a high availability of nutrients that allows nitrophilous and ruderal species (fast growing and disturbance-tolerant species) to invade and restricts the establishment of less competitive species during early succession (cf.…”

“…[84,85]). However, the fact that continuous grazing management contributes to the removal of nutrients explains the reduced abundance of nitrophilous species during the second successional time step.…”

“…An increased availability of nutrients may result in greater above-ground production of biomass (cf. [85]), which, in its turn, influences the light conditions within the vegetation canopy: an increased leaf area represents a common adaptation to low light environments [38,88].…”