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Fens are the predominant peatlands in temperate regions and provide key ecosystem services such as water retention and carbon sequestration. Under threat of drainage, discharge of polluted water, and subsequent eutrophication, fen conservation is a priority. A key feature of fens is their high biodiversity, particularly of specialist bryophytes that play a pivotal role in peat formation. Since many mosses are poor competitors, increased growth of vascular plants following eutrophication is often remediated by annual mowing with litter removal. The precise mowing method favoring bryophytes is rarely investigated, yet creation of “recruitment gaps” by mowing of the bryophyte layer has been recommended. We performed a 3‐year field experiment with three annual treatments: (1) mowing of the bryophyte and vascular plant layer to create gaps, (2) only mowing of vascular plants above the bryophyte layer, and (3) not mowing. Our results show that mowing of bryophytes is detrimental for endangered bryophytes, specifically Sphagnum contortum, S. teres, Warnstorfia exannulata, Calliergon giganteum, and Hamatocaulis vernicosus. Only the generalist species S. palustre and Calliergonella cuspidata benefited from bryophyte mowing. We also found that accretion of the bryophyte layer and development of micro‐topography are impeded by bryophyte mowing, potentially hampering future water retention and carbon sequestration. Nevertheless, mowing of vascular plants proved necessary as fen specialists S. teres, S. contortum, S. subsecundum, W. exannulata, and Bryum pseudotriquetrum declined in the unmown treatment. We conclude that, if mowing is necessary to remediate eutrophication, it should be restricted to vascular plants, particularly in fens with endangered bryophytes. [ABSTRACT FROM AUTHOR]

In tropical regions the extent of agricultural land is increasing rapidly at the expense of natural forest, with associated losses of biodiversity and ecosystem services. Agroforestry has long been proposed as a more sustainable agricultural system, conserving biodiversity while providing significant local livelihoods. In this context, camera traps were deployed to compare communities of large mammals between natural forest (22,272 hours across 24 deployments) and extensively managed coffee forest (19,059 hours, 23 deployments) for the first time in the south-west Ethiopian highlands. Mammal communities in the two forest types were similar in species richness and Shannon diversity but differed in community composition. Significant indicator species of coffee forest were the crested porcupine Hystrix cristata and the Ethiopian hare Lepus fagani, whereas leopards Panthera pardus and civets Civettictis civetta had a preference for natural forest. The number of detections of mammals was higher in coffee forest, where activity patterns were predominantly crepuscular and nocturnal, which may be a direct adaptation to frequent human disturbance. In natural forest, mammal activity peaked during daytime. Despite the high mammal diversity in extensively managed coffee forest, it cannot fully replace natural forest as a habitat for large mammals. We suggest that a balanced landscape mosaic of coffee and natural forest may be a valuable combination for both conservation and coffee cultivation. [ABSTRACT FROM AUTHOR]

Many peatlands have been affected by water table drawdown and carbon loss. Rewetting may push a drained peatland back towards its pre-degradation state and may result in renewed carbon accumulation, but there is little consensus on its effectiveness. Moreover, rewetting typically leads to a spike in methane emissions. Whether rewetting suffices to restore drained peatlands hinges to a large extent on whether microbial communities, and the functions they perform, are able to recover. We studied prokaryote communities in fens across temperate Europe using high-throughput amplicon sequencing of 16S rRNA, within the framework of RePeat (REstoration and prognosis of PEAT formation in fens - linking diversity in plant functional traits to soil biological and biogeochemical processes 2016-2019; BiodiVErSA). We included undrained, drained and rewetted fens to evaluate the effects of fen rewetting on microbial recovery. Prokaryote communities were highly stratified with depth, and there was a clear division between communities of drained and undrained fens. Prokaryote communities in rewetted fens were largely similar to those of undrained fens, but only where soil organic matter contents and bulk densities were respectively still high and low. Our results suggest that altered physio-chemical peat properties following drainage may hamper complete prokaryote recovery after rewetting, at least in the short term. [ABSTRACT FROM AUTHOR]

Peatland degradation is tightly connected to hydrological changes and microbial metabolism. To better understand these metabolism processes, more information is needed on how microbial communities and substrate cycling are affected by changing hydrological regimes. These activities should be imprinted in stable isotope bulk values (δ 15 N, δ 13 C) due to specific isotopic fractionation by different microbial communities, their metabolic pathways and nutrient sources. We hypothesize that stable isotope values and microbial abundance are correlated and act as indicators of different hydrological regimes. We sampled an East-West transect across European fens in 14 areas and conducted a stable isotope (δ 13 C, δ 15 N) and membrane fatty acid (mFA) analysis. Within each area an undrained, drained and rewetted site was selected. Rewetted sites were separated based on when rewetting occurred. We found differences in the upper layers of all sites in microbial-derived mFAs and stable isotope values corresponding to hydrological regimes. The highest and lowest quantities of microbial-derived mFAs were measured in undrained and drained sites, respectively. Fungal-derived mFAs were especially lower in drained sites. Simultaneously, δ 15 N stable isotope values were highest in drained sites. In addition, stable isotope values and microbial-derived mFAs showed distinct depth trends. In undrained sites stable isotopes values slightly increased with depth. In drained sites, δ 15 N values decreased downwards, whereas δ 13 C values increased. Overall microbial-derived mFAs decreased with depth. These patterns presumably result from anoxic conditions and high peat recalcitrance in the deeper layers. In sites with short time of rewetting, the microbial-derived mFAs and stable isotope values were similar to values of drained sites, while with increasing rewetting time values shifted to those of undrained sites. We conclude that biomarkers indicate that stable isotope values reflect specific microbial metabolic processes, which differ with hydrological regimes, and thus could indicate both drainage and rewetting in fens., Competing Interests: Declaration of competing interest The authors declare that they have no conflict of interest., (Copyright © 2022. Published by Elsevier B.V.)