River restoration is widely applied, although its effects are poorly understood, and degraded habitats might be difficult to improve. Moreover, there is a lack of monitoring as well as few systematic comparisons of restoration methods. This study presents results of a 4‐year monitoring on River Inn (southern Germany) investigating restoration by gravel or sand addition or embankment removal. The results were compared with reference sites that represent the pre‐restoration conditions. At the landscape scale, we analysed vegetation types based on aerial photographs, whereas at a smaller scale, we undertook vegetation surveys and evaluated species composition, growth, and life form, as well as the proportion of the target vegetation. After 4 years, the data indicated a “negative resilience” of the vegetation back to the state prior to restoration. The structural analysis revealed an extensive spread of reed at expense of bare soil. Thus, the species composition largely regressed to the pre‐restoration conditions, and neither annuals nor other pioneer species showed a long‐term benefit of river restoration. There were differences among the three restoration treatments after 2 years, but no longer after 4 years. However, the river restoration had three positive outcomes: (a) There was a temporary benefit for pioneer vegetation that most likely replenished the seed bank of the respective species, (b) the valuable reed communities showed resilience, and (c) the measures allowed some practical learning as expected for adaptive restoration.

Question: Does long-term visitor trampling close to hiking trails affect the taxonomic and functional composition and diversity of a calcareous grassland, thus reducing its nature conservation value?Location: Ancient calcareous grassland (nature reserve Garchinger Heide) in the Munich Gravel Plain, south Germany.Methods: We sampled plant species composition at four distance classes representing different trampling intensities along replicated transects running perpendicular to 20-yr-old hiking trails in the nature reserve. We used a combination of distance-based multivariate methods and a series of univariate tests to study the effects of trampling on a number of conservation-relevant aspects of taxonomic and functional plant community composition and diversity.Results: The different trampling intensities led to a significant variation in plant species composition that was driven by trait-mediated responses, mainly of traits related to dispersal and regeneration, but these patterns only occurred close to the trails (<1.5 m). Except directly on the trails, species richness, the number of habitat specialists and threatened species, as well as Functional Richness were not or marginally affected by trampling. Multivariate dispersion within levels of trampling intensities and evenness, the latter measured for either species or traits, remained constant across the gradient of trampling intensity.Conclusions: Even after 20 yr of exposure to different intensities of trampling, calcareous grassland vegetation showed only few and spatially limited compositional responses, while its nature conservation value was not affected. Therefore, marked hiking trails are a good compromise between meeting the needs for recreation and environmental education, and the conservation of threatened habitat specialists and should be preferred to alternatives such as undirected access that would result in spatially extensive changes in community structure.

Drainage and afforestation of peatlands cause extensive habitat degradation and species losses. Restoration supports peatland biodiversity by creating suitable habitat conditions, including stable high water tables. However, colonization by characteristic species can take decades or even fail. Peatland recovery is often monitored shortly after restoration, but initial trends may not continue, and results might differ among taxonomic groups. This study analyzes trends in plant, dragonfly, and butterfly diversity within 18 years after rewetting of montane peatlands in central Germany. We compared diversity and species composition of 19 restored sites with three drained peatlands and one near‐natural reference site. Restoration resulted in improved habitat conditions and benefited species diversity, but there were marked differences among taxonomic groups. Dragonflies rapidly colonized small water bodies but their diversity did not further increase in older restoration sites. Characteristic peatland vegetation recovered slowly, since it depended on a high water holding capacity that was only reached after peat started accumulating. Generally, plant diversity developed toward reference conditions albeit incompletely, even 18 years after restoration. Butterflies responded less to peatland restoration; generalists increased only temporarily and specialists could not establish. In conclusion, peatland restoration improves habitat conditions and biodiversity, while trajectories of recovery are nonlinear and incomplete after two decades. This highlights the need for long‐term monitoring and a strategic selection of indicator species for evaluation of restoration success.

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Ecological restoration has great potential for reversing anthropogenic degradation, as it aims at the simultaneous recovery of several ecosystem functions and services. However, it can be challenging to evaluate multiple restoration targets based on a high number of indicators, and this calls for a multifunctionality approach. Multifunctionality is an integrated measure of the relative supply of multiple ecosystem functions or services. As temporal aspects are of key importance for ecosystem recovery, we analyzed multifunctionality against time since restoration. We used rewetted peatlands in a mountainous region in Central Germany as a study case. Restored peatlands are expected to become multifunctional, while their recovery is rather slow.We investigated to what extent rewetted peatlands recover, and how time since restoration controls the simultaneous development of multiple ecosystem properties. We studied restored peatlands with respect to plant diversity, water table, peat decomposition, water holding capacity, and nutrient level using a chronosequence of 0-18 yr after restoration. We analyzed the development of individual properties and of a combined index. We further compared the recovery of restored sites at different ages to an intact reference peatland and to a theoretical optimum value, defined as the mean of the eleven most desirable values observed. Eleven out of 13 peatland properties and the combined index significantly evolved with time since restoration. Nevertheless, we could not observe a consistent trend of multiple properties if aiming at highest levels of functioning, whereas there was progress with time if low or intermediate functioning is targeted. Our results show that not all functions of restored peatlands can recover to the most desirable extent within 18 yr. However, the average functionality and some individual properties achieved levels comparable to the reference site, highlighting that improvement is possible. While the integrated assessment informs about the degree of ecosystem recovery, an additional analysis of individual properties helps understanding ecosystem-specific dynamics, which are needed for making decisions on potential future management.