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Plant–soil feedback (PSF) results from the net legacy effect that plants leave in the composition of soil communities and abiotic soil properties. PSF is induced by the rhizosphere and by litter inputs into the soil, however, we have little understanding of their individual contributions. Here, we examine feedback effects from the rhizosphere of living plants, decomposing litter and their combination.We used four pairs of climate warming‐induced range‐expanding plant species and congeneric natives, and examined PSF effects on plant biomass production, as well as on decomposition in their new range.We tested the hypothesis that the plant rhizosphere provides less negative feedback to range‐expanders than to the congeneric natives, and that feedback mediated by litter decomposition does not provide such a difference because decomposers might be less specialized than pathogens. To determine PSF, we used soil from the congener species within each pair as an ‘away’ soil to indicate whether range‐expanders may have lost their specialized soil biota upon arrival in the novel range.Our results show that although range‐expanding plant species and their congeneric natives developed neutral PSF in both rhizosphere‐ and litter‐conditioned soils, two of the four range‐expanders produced more biomass than natives in soils conditioned by litter, that is, soils with high nutrient content. Shoot litter from two out of four range‐expanding species decomposed more than that of natives, but decomposition was unaffected by soil conditioning. Synthesis. We compared PSF effects of range‐expanders and congeneric natives mediated via both the rhizosphere and litter using the congeneric species as a control. Under those conditions, PSF effects were neutral and not affected by plant origin. Therefore, we conclude that studies not comparing within plant genera may overestimate the impact of plant origin on PSF. Still, even under those conditions range‐expanders appeared to benefit more from high soil nutrient availability than natives, thus providing a possible advantage over congeneric natives., We compared Plant–soil feedback (PSF) effects of range‐expanders and congeneric natives mediated via both the rhizosphere and litter using the congeneric species as a control. Under those conditions, PSF effects were neutral and not affected by plant origin. Therefore, we conclude that studies not comparing within plant genera may overestimate the impact of plant origin on PSF. Still, even under those conditions range‐expanders appeared to benefit more from high soil nutrient availability than natives, thus providing a possible advantage over congeneric natives.

Restoration of riparian plant communities on bare soil requires germination of seeds and establishment of seedlings. However, species that are present in the soil seed bank do not always establish in the vegetation. Temperature, moisture conditions and soil type could play a major role in the establishment of riparian plant communities, through impacting seedling emergence.We studied the effects of temperature, combinations of temperature and moisture conditions, and soil type on seedling emergence and mortality of perennial reeds (Typha latifolia and Phragmites australis) and annual or biannual pioneer species (Senecio congestus, Rumex maritimus and Chenopodium rubrum). The responses to the environmental conditions were species-specific and resulted in context-dependent differences in proportions of species emerging from the soil seed bank. Typha latifolia and S. congestus preferred wet or very wet conditions, C. rubrum and R. maritimus preferred dry to very dry conditions. Phragmites australis was able to establish under all conditions. Both cold and very dry conditions resulted in low emergence and survival, which was not fully compensated for when conditions became favorable again. Senecio congestus, R. maritimus and C. rubrum benefitted from secondary seedling emergence when, after a very dry period, the weather became very wet again, while T. latifolia and P. australis remained absent.When the conditions remained wet, more seedlings emerged from sand than from clay. However, when the soil was drying out, fewer seedlings emerged from sand than from clay.We propose that using information on plant species-specific responses to abiotic environmental conditions during germination, emergence and establishment can help to restore different target riparian plant communities.